The issue is not really whether the machine is level, but is rather that it is square to itself, and will maintain such squareness. I say this because after spending a couple of enlistments in the Navy, level is something that is relative to the center of the Earth, and not usually pertinent to machine function. Ensuring squareness is much more important to machine function (most any machine) than is levelness. And using the correct terminology when discussing such things is important so as to not introduce confusion into the subject. I am glad that you did talk about squareness when setting up a lathe.
Joe, finally somebody comes out what I was saying 10 years ago when I was member of the Atlas group. They We t buta. They poured a voncrete leveles top for a 6” Atlas. TUBALCAIN also also. agreed me. My point was how do you level a lathe on a ship? They mixed twisted beds with leveling.. Thanks for explanation in an unmistakable way. I am also planning to clear the misunderstanding about “vertical shear”. I am watching your work, terrific job. Congratulation. Bob
The lathe and mill at work are of the same brand. We were having a problem with the mill, called a Mfr. rep out. As it turns out he was the same person who set-up both machines when they were delivered. As he walked into the shop he glanced at the lathe saying "Who and why did someone screw with the leveling, bet it is cutting a taper." (there were other Machinist in the shop before us). It took this guy all of 10 min to dial in the late to a half thou over three feet. That was impressive! Great video and explanation as usual, Joe! You have a knack of making it all make sense.
Wow, now I can see the light ! As a novice I would have never though about the influence of the headstock on the center line of the bearings. It just makes lots of sense now. Many thanks for sharing your invaluable experience !
Very clear and informative. Thanks. Over the years of watching all you folks in the UA-cam machinist group, I have come to understand how even monolithic chunks of metal regularly deform and shift, and how that influences accuracy. Extreme examples as you show in this video are a sure way to understand how subtle changes within a system can affect major errors.
So basically to check the head you face the part as close to the head as you can. Then check it by moving the part out say 10 inches and skim cut it again. If the head is out it will show up in the face as being out of square. If the ways are twisted the the machine will cut a taper. Thanks for the video, this gives me some ammo to help convince management to have our lathes looked at. We have one machine that is cutting a .004 taper in ten inches or .0004 per inch. Kind of hard to hold .0002 to .0005 tolerance on 4 inch long parts. (Interference fits on couplings) with machines that don't cut straight to begin with.
I had the opportunity to run an identical lathe for about 6 years, along with other toolroom machines. It had DRO's and was the finest lathe I ever used. I have used alot of fine machines in my life and this was one of them. It accomplished some exotic work for me.
Joe great lesson in alignment of the lathe. One of the interesting features on the Colchester lathe is that if you remove the side cover of your headstock you can see where provisions were made to adjust the spindle alignment in relation to the ways in or out. Up and down is done with shims or scraping under the head and final alignment is done when placed into service. I have rebuilt several larger 21"version of the model lathe you have that have this provision not 100% sure if the Student does. I have not seen this on another lathes I have worked on. The Colchester head doesn't sit on prismatic ways like Monarch does so they have to be spot on leaving the factory. Happy Diving Zed
Joe I agree just a slight twist sometimes is just enough to get the machine to cut straight. I prefer the tail stock end slightly lower to get the coolant running south. All good information thanks for posting. Best to you.
Thanks, Joe. Excellent video. Simple but informative. I had asked a question about this a while back and was hoping you would address it at some point. I hadn't considered the influence of those far left adjustment feet. I was just keeping even force on them compared to the other two. That did the trick for me and I'm a happy camper. Thanks again.
A great example of why Level isn't 100% the best way to describe it is the fact that every ship in the Navy has an engineering room with a lathe in it rocking around with the sway of the ship. Also like your Clausing-Colchester, a decendant of my old Clausing 1500,
I knew about the level bed part but I’ve never considered the headstock being parallel with the bed. Thanks for this info I know what I’ll be doing on my lathe next
Thank you Joe, that video was very helpful. I am a hobby machinist and the way you illustrated the motions at work really increased my understanding of tuning up my lathe.
Joe the only thing that you did not mention is run a spider front and back of the head stock and indicate both the rear and front at the spider's .because if you have not set up the chuck the jaw's and or the scroll can be out there by given a false reading number one to level is to have perfect aliment with the spindle . just my 2 cents worth . :)
Thanks Joe. I have acquired a new to me lathe. Very excited about it and been pondering this leveling process. Very timely for me to see your video and thanks as it is making sense.
Great video. As an advanced beginner I could never understand why the lathe had to be "level". I always thought it was in relation to the floor and couldn't figure what difference that would make. Now I understand that level is actually better described as a type of twist. Luckily my lathe has always been "level" with no problems.
Great model, very clear to the the hobbyist. Always a bone of contention, ref lathe leveling. You are levelling the lathe, to de-stress and align, using an accurate engineering level. Large lathe builders will grip a suitable diameter thick wall tube in the chuck, turn the OD with no steady or centre, and adjust level to minimise taper. Place level on the as turned of, this should now agree with the overall level reading. Your engineering or machinists level should have an accuracy of 0.05 mm per Metre or 0.0005" per 10", there are more accurate ones, but you can achieve a reasonable result on small sub 1 metre or 3 feet bed length with a 0.5 mm per Metre (builders level). Thanks for sharing Joe, and best regards from the UK. Lathe leveling on a ship is the same,
I heard someone say / write years ago about lathe "leveling"... There are lathes on battleships. Level by itself doesn't mean a lot. Twist and contortion ruins accuracy.
When you think about the word "level" just think of all the lathes that were and probably still are in ships, portable machine shops, etc.. They cannot maintain them in a "level" condition.. The twist and flex in the bed is much more important....I have a 1942 LeBlond trainer on which I set an indicator on a work piece between centers..Change shims under the feet and tighten the bolts slightly and watch the indicator needle move.. Mike in Louisiana
When I ret 11 years ago,my wife bought me a14-40 in. grizzly lathe. I know bought across the pound.I leveled it up,with a sterett prec. level like you inst., with the help of a 40 year machinist. I can hold .ooo5 with no digiital read out. .still 11 years latter . The old machinist still comes down on his walker to do his little projects ... Also no taper on a 2 ft. shaft It was below "o" in the garage had to reline it once. In warmer meather.. Wisc. winters
Some lathes (such as mine), the ways run all the way under the headstock, and the headstock rests on the bed like the carriage. These lathes have only 4 leveling points. So bed twist is the only thing needing worrying about. Comment about headstock alignment: you really need to do the indicating UNDER the work on the tailstock end to detect bend, and indicate IN FRONT of the work to detect bed twist.
Lathes should be mounted on a rigid base and the mounting tuned to make straight cylinders. On land gravity provides a reference. I have worked on lathes and other machine tools mounted on a ship. On a ship gravity is rarely perpendicular to anything.
I'm glad you had a great trip and have returned safe and sound! Thank you for the information about lathe leveling it's very useful! This old Tony's was useful too, but your example was spot on! Again Joe, Thank you sir!
I think the reason they say "levelled" is because most people have something that will accurately repeat "level", but not everyone would have something that can accurately repeats 3.842*. From what I gather from this, you should level the headstock first, Square up the headstock to the bed, make sure the bed is level near the headstock, make sure the axis of the head stock is level, and then adjust the feet on the end by the tailstock until that is level as well, and you'll probably have to go over it a couple times before thing settle in
Great video. I was in the process of refurbishing and setting up my lathe (until my recent health issues), and this will come in handy when I am back in my shop. Love the Clausing lathe.
Great well demonstrated video as usual Joe. I've also never been able to figure out why "lathe leveling" is so misunderstood on the forums. It really isn't that complicated for what needs to be done and why it needs to be at least checked. Using a decent machinist's level is just the easiest way to get the bed straight and parallel. Actual "level" as you said isn't even needed, it's just the quickest and most simple way to measure and adjust to end up at that non twisted straight and parallel condition. At a minimum the free online PDF of Dr. Georg Schlesingers book Testing Machine Tools should be required reading for anyone who owns or operates machine tools. Read through that enough to grasp the concepts being explained and why each test is being done. The equipment & getting any machine tool properly aligned then gets a whole lot more simple. The Moore Tools book Foundations of Mechanical Accuracy also gives some of the best diagrams of the causes of machine tool inaccuracy or misalignment and how it affects a machined part I've seen so far. I'd also add that even getting a lathe perfectly dead level is still only a static condition. I've proved to myself that very minor final tweaking is almost always required due to the machines various parts flexing just enough under the cutting loads to make a measurable difference if your trying for the absolute best the machine can do. Then you do need to know which adjustment screw needs moving and in which direction to roll the cutting tip slightly into or out of the cut.
@@joepie221 LOL, you have it easy. My shop floor is the usual wooden construction. I can get my smaller lathe than yours to turn perfectly parallel and two hrs later with a few changes in humidity or temperature it's turning a measurable taper. So I've had to do a whole lot of adjusting over the years. It's taught me a lot about that "lathe leveling" but the problem is obviously something I'd rather not have.
Aloha Joe, "great minds think alike and fools seldom differ" and my wife never would say which side I was on.... I agree with you completely, but have known few who agree with us. Most say level the ways then tweek the tailstock end to bring the taper out of your work, I never could understand, or agree with that. Now with the aid of your "state of the art" training aid it all becomes clear, I hope my friends were watching. As to the training aid isn't "modern technology" wonderful? Keep the great source of common sense coming our way. Mahalo nui loa. Aloha ke Akua.
The hinge point is probably more of a bow point, but the end result is the same. Hawaii was beautiful. I'd like to go back someday under different circumstances and do some diving. Kona night Manta ray dive ----- Bucket list.
Brought my used lathe home Put my level on it and it seemed to be perfect But when i trammed a round straight piece between centers my tail stock is low Moving the tail stock closer to the chuck reduces the error Now this helps me understand it I think its exactly like you are saying it is
Anything pinched between centers shouldn't show much difference as demonstrated. Don't rule out way or tailstock wear. if you want to tram the tailstock, do it with a long bar and indicator in a chuck. Don't use a bar that will sag.
Excellent video. I'm just getting into machining, have a 10" Atlas lathe, and I'm probably not going to get it dead on, but.....at least I know and understand now the hows and whys.
Newbie to lathe work, Joe you’re a great teacher, no BS straight to the point and easy to understand. Thank you! I bought a second hand Grizzly G0750G lathe and I decided to bolt the cabinets to the floor and make adjustable riser blocks between the cabinets/stands and the lathe. My thoughts are, because the stands aren’t ground true it would be easier/faster to true just the lathe and not both cabinets & lathe. Is this method asking for trouble?
As long as the lathe is sitting on a surface rigid enough, it should be fine. If the machine is heavy enough not to walk around, or fall over on top of the cabinet it should be OK.
Hi Joe, I also jack up the machine in order to minimize taper! I'm a bit afraid to do adjustments to the head stock alignment, as I cannot (easy) confirm or verified dis alignment from top or bottom. Now I got a half thou over a distance of two inch round stock , (diameter 2 inch) cutted direct from the head stock! (not between centers) I hope I can improve this, as I do cylinder boring over 6 inches, and after the boring operation, I still can honing the iron linor straight, but I prefer that it comes from the machine with minimum taper! Anyway, got again useful information from this video! Many thanks.
Interesting vid, kinda reinforces what I had thought about people rigidly bolting lathes down then trying to get everything level. I only have mini machines now so can use a long MT3 drill blank in headstock for checking and just haev them sitting on wood blocks
Thanks, excellent information. I knew Part I of the info (removing bed twist) but not about the head leveling. I'm cutting a noticeable taper on my 14x40.
Hey Joe, I concur, some folks search for to much information and the problem becomes blurred. Your video should clear that up. Mike from Plus8Precision
... and by the way, many people don't have a precision level anyway. The South Bend manual defines a precision level as "sufficiently sensitive to show a distinct movement of the bubble when a 0.003" shim is placed under one end of it." A precision level is certainly a good reference tool to determine if the lathe is true to itself, but can you imagine a Machinist's Mate calling up to his commanding officer, "Captain, find me a calm sea and stop the fleet. I have to make my final cut."
Only 4 feet on my hobby size lathe! When I installed it I mounted a DTI on the tailstock, reading off the end of a 1Ft bar in the chuck, and made sure no deflection as I tightened the bolts down. As for 'level' I just made sure the whole assembly ( stand & lathe) tilted down towards the suds tray drain fitting.
Thanks again Joe, as per usual you have pointed out something else that we should consider, you mentioned about a round bar that you can measure from, what sort of thickness should we be looking for, would a ground bar be better (we normally use a 25mm ground bar by 600mm long to set up our A axis when we put it back into the concert). Thanks for your help, I for one feel like I have learned quite a few tricks from you that helps me out a lot! Thank you...Phil
Wish I had known or realized this in 1981. Worked civil service Coast Guard in one of their Base Welding/Machine Shops. Had two old lathes, a La Blonde and a Southbend. The La Blonde had a wicked taper on the tail stock end and could Not figure out what the heck was wrong. Both were Pre WW II machines to give ya an idea how old they were & both off a Navel ship out of their machine shop on board. Well thank you for this old mystery clear up. Hint - was not a machinist - OJT all the way, was wielder by trade.
A few comments and questions: As far as I can see, your ways looks bolted to the headstock. To me it suggest, if it is true, that you can level your headstock as a unit, and then level your bed in line with that. The 6 leveling feet you have on your machine, I have not seen in the now 12 different marks and models of lathes I have been in contact with, they all only have 4 levelers. Also all the lathes I have seen, the headstock is bolted on top of the bed, and thus have to be shimmed to change the "centerline" according to the bed. I am with you as far as you can, to some degree, level out warp front/back on a bed, but it means that you have to bolt down the cabinet to the floor, and many amateurs have their shop in a basement with wooden floor, at least in Denmark and Sweden. Otherwise an very informative video as most of your videos are.
Timing. I have half done one of two lathes today at work. Monday I finish the jobs. Great demo. Mine also have 4 bolts at the tailstock end. Never worked with that before.
I ran an 18-140 gap bed Mazak for many years. It had a center island on the bed because it was so long. Imagine how that came into play for the guys that set it up.
@@joepie221 I never got to see them but my father set up old ww2 lathes that made the barrels for big war ships when he worked with the dep of defence. That would have been one interesting experience.
I agree with @componenx. Having served on numerous navy ships, including a repair ship, I would say it could be mounted on the overhead, as long as the be is not twisted. I have my two lathes mounted on glue-up wooden bench tops (suggested by Atlas), and held down by two lag bolts through the from legs, allowing the rear ones to float. Works fine for me.
"Level" is used because using a level to set up alignments is the easiest thing to do. It is the easiest way to use the tool involved. Trying to set the lathe to be aligned to a 20deg inclined plane would be more challenging using levels especially since as you tip a level over it becomes inaccurate due to the curve in the glass that forms the bubble. It is also possible if you install a lathe very much out of level you could have lubrication issues as the oil level in all components was designed for being on the "level".
The confusen for new to the trade is probably that the three main reasons for leveling was not really well explained in perspective, like for fluid requirements, heavy weight requirements and the culprit the ways to headstock alignment assist.
Putting the level on the top of the ways is an assumption that the top of the ways are true to the load bearing section of the ways. Since we are measuring bed twist and not level I feel it would be more advantageous to put the level on top of the cross slide. Then move it from one end to the other. You can look at the load bearing part of the ways as the supplier and the cross slide and tool post as the end user. The end user is what you want to check, not the top of a V way that has no function other than to take up space. All this assuming your ways aren't worn out which seems to be a growing problem with older lathes.
Agree. In Sweden we talk "technical surfaces." Some take pressbrake tooling, use the outside as distance blocks and I tell them they are not true. They say they are true to the thousands and they are but only on the technical surfaces.
Another thing to be checked is the horizontal alignment between the head stock spindle axis and the bed. This isn't a common problem on lathes where the head stock actually sits on the bed flats and V-ways. The head stock is scraped in at the factory. That said, if it is out of specification, the only cure is to remove the head stock and re-scrape it to fix the misalignment... not a job for the average machinist to do. This is a task for a machine rebuilder. Where it can be a problem is on the smaller Asian built lathes. The head stock doesn't sit on the lathe V-ways and flats, but sits on a flat machined surface under the head stock. The head stock is bolted to the bed with four bolts (usually) and there are two horizontal jacking screws on an overhanging lip on the back side of the head stock. The good news is if alignment is called for, the head stock can be shimmed for vertical alignment and the jack screws can make adjustments for horizontal misalignment. This is also the time to make sure the tail stock quill and head stock spindle center lines are the same height. Also make sure the tail stock quill is parallel to the bed both vertically and horizontally. Faults in this area show up when drilling very small holes. You will notice the drill flexing to pick up the center of the rotating work because of misalignment and moving the tail stock side to side won't cure the problem. If you have an inspection sheet for your lathe, use that to inspect the lathe's condition and make adjustments as necessary. Many of the older handbooks give general alignment specifications for tool room lathes if you don't have specific tolerances for your machine. Cheers from NC/USA
Straight is important , but level is extremely important in a job shop for set up of odd ball parts esp line boring & assisting with steady set up's on long shafts . Cheers .
Maybe a better term to use instead of "level" would be "True?" As long as the head stock and bed are parallel / perpendicular is the key since the term level is relative to so many factors especially mobile machines in ships etc.
@@swanvalleymachineshop When I commented to the term level in my comment, I wasn't referring to spirit levels. I was commenting on the topic that Joe brought up about how the term "Level" had been, in his opinion, too broadly used. Many seasoned machinists will say that a machine doesn't have to be truly level as long as the bed is true to the plane the bed resides. I agree that spirit levels are often a good choice when trying to get a part set up.
people dont think cast iron will bend,twist,warp. but. it WILL do all this stuff. alas is true. the phrase should be relativly inflexable. when you think of the fact that "most" machines are "seasoned" cast iron. the soaking pit changes iron! poppy
Joe When people say they have levelled their lathe and not done any accuracy checks just make me ROFLMAO. Then I ask them why is it important to get it level to the big ball we live on Yes it can help on a mill to set up a job Then I ask them how do you level a lathe on a ship ? As you know the do have machine shops on board ,certainly not at sea , could it be done on dock maybe , dry dock again maybe , is the ship floating level I doubt it very much but as you say the lathe must be true to itself , and be without stress , if it’s set up that way to be truly level to the big ball matters a jot keep up your very informative vidieos Now I must get down to the WS and get the concert mill warmed up and make some parts for my miniature triple expansion engine , while that doing its stuff do some bits on the manual mill , lathe work to come later 😀
Harold Hall outlines a nice procedure in his Lathework book on cutting a cylindrical square as a test for headstock alignment. On the (tiny) Taig, I was able to get within a tenth. My newer 13x40 Colchester clone was close enough without adjusting the headstock, fortunately, since while it has better provisions for adjustment, actually getting at them requires a lot of fiddling.
That's a great presentation. I see a lot of cases where a machine mover contractor hires another contractor to laser the machine and comps it out to be "straight", instead of physicaly leveling the machine. The people doing that have no clue what to do to make it right. All they do is introduce stresses into the frame castings and allow the machine to get bent.
On large CNC machining centers, the head is fixed and the column is rigid. You actually have to tweek the level of the table with the machine feet to indicate the spindle. reverse procedure, but the only way to do it.
There is a long list of different kinds of design when it comes to machine tool machinery. The good ones are heavy and rigid with a properly built foundation and no soft feet. I'll take an old American design like a Producto, Gray or Cincinnati Milicron that has replacable ways over anything imported with ways machined out in the frame like a Mazak Y, or YB. Too bad that most domestic machine tool makers have been sold and no longer in operation. I look at it from maintenance prospective because thats what I do for living. Older designs are easily upgraded with modern controls, but sometimes the people who make the decisions to purchase equipment don't have a clue what's good.
Another great presentation. Thanks. Newer lathes present another problem. The headstock does not locate on a V way. It has jackbolts to align the spindle centerline with the centerline of the bed. How about a short video addressing that adjustment?
Headstocks aligning on the Vee are the suck. level the bed to remove any twist. Put a 3" diameter aluminum pipe 14" to 16" long in the 4jaw, and make test cuts with a shear tool, and measure the diameter at both ends. If you need to align the head stock, keep in mind it will shift when the bolts are loosened. So put an indicator at either end of the tube before loosening the bolts. Once the horizontal alignment is complete, sweep the top of the tube to verify vertical alignment. I disagree with Joe on the importance of vertical alignment, it has to be way off before it has a meaningful effect on the taper. This is just simple geometry. Fire up Fusion 360 and check for yourself. For example, if the headstock points up 0.050" at 12", the result will be about 0.0008" taper. The smaller the diameter the bigger the affect. 0.015" mis-alignment will give about 0.0009 taper.
You addressed vertical alignment very well. Not discussed was the use of jacking screws to shift the headstock front to back. I know hoe to do it with a 2 collar test bar held in the chuck. I am betting there are a lot of viewers who could have benefited from that discussion.
Similarly, when I worked in pre-press layout dept. (stripping dept.) at a printing company, we had 60” T-squares that would ride on a straight edge on the side of a 4’x6’ light table. You would tape two pins down to the glass of the light table using the T-square and all the acetate sheets would be punched and register to those two pins. These T-squares were solid stainless with a machined steel head attached solidly with screws. A precision piece. I started in a new shop and one of the journeyman lay-out men, yes, we called ourselves strippers, would, for a small fee, take your T-square home and “calibrate” it. I.e. knock the head on the floor to get it EXACTLY 90º. I was the new kid, around 25, but had been at it for 7 years or so, and he eventually got around to me. I told him no thanks, that the angle being 90º was not important since we attached the pins to the table using the T-square and as long as it was solid and you did not switch T-squares between the different taped down register pins everything was cool. All that mattered was that all the lines stayed parallel. He argued for a while but eventually gave up. I don’t know if he ever figured it out.
I have read several comments about the test bar deflecting up to and including using a ceramic test bar to prevent it. There is no reason to worry about a test bar deflecting from it''s own weight. There is a simple way to test for deflection. Set bar on flat surface set one end on something of known height and square and measuer with other end hanging out. anything can be used around the shop to do this including two tool bits of same thickness to two round bars or anything as long as it's square or of the same thickness. You dont have to break the bank buying stuff. Say the pedestals you have the bar on are 1/2 inch and the bar is 1 inch. If the bar is deflecting you will see it when you measuer, the end supported will be 1.500, the hanging end will be less. Which it wont be but test if you wish, at least you will know.
"Which it wont be but test if you wish, at least you will know"... "There is no reason to worry about a test bar deflecting from it''s own weight"... Do they omit tuition on the subject(s) of Airy and Bessel points at engineering colleges nowadays? At the very least, you must have had the Airy points on a precision straight edge pointed out to you in the metrology / mensuration module? Deflection's real, but often immeasurable and immaterial in the normal workshop. www.engineeringnotes.org/metrology/airy-points-and-bessel-points/ Most of us spend our lives in "normal" workshops, but if you visit places where gas or steam turbines are made, or car components, or gauges such as Johansson blocks, or antifriction bearings, or precision machinery, or gauging systems are made, where temperatures, air quality and humidity are closely maintained, and where even fifty and more years ago, air gauging systems were measuring to millionths of an inch www.qualitymag.com/articles/88856-quality-101--all-about-air-gages Your flat surface? how flat? Guys use ground plate, assuming it's flat, forgetting or not knowing it won't be, as can be proven with a diffraction grating interferometer... Energize and clock a magnetic chuck or table with a tenths clock in both planes, at 1/2" intervals It'll not be flat. Surface plates and marking plates are often confused (unless you get the bill, and see the huge difference in price...) Your mandrel? (bar) how round? It's a surprise when the Talyrond is applied to a newly ground, "perfectly round" workpiece, and you find the trace is like a ploughed field... It's all a matter of degree, but awareness of the more esoteric engineering phenomena can make a huge difference at interview if you're seeking a move into a better class of engineering work (which may be a retrograde move, causing more headaches and paying less) I was aghast at the rate I was offered for toolmaking work, in the seventies, so I took a job on maintenance. Rough and dirty, but the pay and freedom from stress...
My lathe (Maximat 11, 11' swing x 24") lathe has the ways project all the way under the headstock, so in effect, the headstock "sits" on the bed like the carriage & tailstock. There are only 4 leveling screws, 2 at each end, so bed twist is all I need worry about (or can do anything about). On larger lathes, the bed usually gets "super thick" near & under the headstock to resist the deflections you are concerned with. Have you measured your lathe, or tried to make these errors happen, to note their severity?
MANY MANY THANKS!!!.. Joe I have spent years in the same discussion with bosses and co-workers. "LEVEL" has to do with the Earth...focus on straight-square-parallel -and dimension...etc. When I see people grab a carpenters level...glance at the vial...see anything of the bubble...then yell..."it's Level!!!" Kills me...or the next best..."Level the part" then machine it...yea....how about the status with the machine and the Earth first..... Those boxes are the best working model of the complexity of an Engine Lathe. Thank you Joe! Keep it up!
The issue is not really whether the machine is level, but is rather that it is square to itself, and will maintain such squareness.
I say this because after spending a couple of enlistments in the Navy, level is something that is relative to the center of the Earth, and not usually pertinent to machine function.
Ensuring squareness is much more important to machine function (most any machine) than is levelness.
And using the correct terminology when discussing such things is important so as to not introduce confusion into the subject. I am glad that you did talk about squareness when setting up a lathe.
Very timely Joe, as I begin to "level" my new lathe. I know the effort and time required to produce these video, and we all appreciate it! Thank you.
Thanks for watching Guy. Much appreciated.
Joe, finally somebody comes out what I was saying 10 years ago when I was member of the Atlas group. They We t buta. They poured a voncrete leveles top for a 6” Atlas. TUBALCAIN also also. agreed me. My point was how do you level a lathe on a ship? They mixed twisted beds with leveling.. Thanks for explanation in an unmistakable way.
I am also planning to clear the misunderstanding about “vertical shear”. I am watching your work, terrific job. Congratulation. Bob
Thanks Bob.
Perfect timing. I have just brought my "new" lathe into the shop and have to "level" it next week.
perfect timing for this video..just relocated my mill and the lathe is being set up in a few weeks time....thanks Joe
The lathe and mill at work are of the same brand. We were having a problem with the mill, called a Mfr. rep out. As it turns out he was the same person who set-up both machines when they were delivered. As he walked into the shop he glanced at the lathe saying "Who and why did someone screw with the leveling, bet it is cutting a taper." (there were other Machinist in the shop before us). It took this guy all of 10 min to dial in the late to a half thou over three feet. That was impressive! Great video and explanation as usual, Joe! You have a knack of making it all make sense.
Agreed. Joe takes something that would fill chapters in book and in 12 min gives a clear picture of what is going on, home to
Even when I think I know everything, I don't. You always make me think. Thanks!
Wow, now I can see the light ! As a novice I would have never though about the influence of the headstock on the center line of the bearings. It just makes lots of sense now. Many thanks for sharing your invaluable experience !
This is the best lathe demonstration I've seen. Thanks Joe.
Very clear and informative. Thanks. Over the years of watching all you folks in the UA-cam machinist group, I have come to understand how even monolithic chunks of metal regularly deform and shift, and how that influences accuracy. Extreme examples as you show in this video are a sure way to understand how subtle changes within a system can affect major errors.
So basically to check the head you face the part as close to the head as you can. Then check it by moving the part out say 10 inches and skim cut it again. If the head is out it will show up in the face as being out of square. If the ways are twisted the the machine will cut a taper. Thanks for the video, this gives me some ammo to help convince management to have our lathes looked at. We have one machine that is cutting a .004 taper in ten inches or .0004 per inch. Kind of hard to hold .0002 to .0005 tolerance on 4 inch long parts. (Interference fits on couplings) with machines that don't cut straight to begin with.
I had the opportunity to run an identical lathe for about 6 years, along with other toolroom machines. It had DRO's and was the finest lathe I ever used. I have used alot of fine machines in my life and this was one of them. It accomplished some exotic work for me.
I love it.
Joe great lesson in alignment of the lathe. One of the interesting features on the Colchester lathe is that if you remove the side cover of your headstock you can see where provisions were made to adjust the spindle alignment in relation to the ways in or out. Up and down is done with shims or scraping under the head and final alignment is done when placed into service. I have rebuilt several larger 21"version of the model lathe you have that have this provision not 100% sure if the Student does. I have not seen this on another lathes I have worked on. The Colchester head doesn't sit on prismatic ways like Monarch does so they have to be spot on leaving the factory.
Happy Diving Zed
Joe I agree just a slight twist sometimes is just enough to get the machine to cut straight. I prefer the tail stock end slightly lower to get the coolant running south. All good information thanks for posting. Best to you.
Perfect explanation Joe. Thanks for all the good advice.
Thanks, Joe. Excellent video. Simple but informative. I had asked a question about this a while back and was hoping you would address it at some point. I hadn't considered the influence of those far left adjustment feet. I was just keeping even force on them compared to the other two. That did the trick for me and I'm a happy camper. Thanks again.
A great example of why Level isn't 100% the best way to describe it is the fact that every ship in the Navy has an engineering room with a lathe in it rocking around with the sway of the ship.
Also like your Clausing-Colchester, a decendant of my old Clausing 1500,
I love these lathes. I have run many and they all perform great. the 15" is my favorite.
Good explanation Joe! I check mine often because it' bolted to the floor. Thanks for the video!
Great video Joe. I like the way you broke down the different things going on.thanks andy.
This came just in time. I'm about to go through the levelling of my restored lathe on my channel. Thanks for the tips, Joe!
Excellent explanation....that's why i like your channel..
I knew about the level bed part but I’ve never considered the headstock being parallel with the bed. Thanks for this info I know what I’ll be doing on my lathe next
Thank you Joe, that video was very helpful. I am a hobby machinist and the way you illustrated the motions at work really increased my understanding of tuning up my lathe.
Glad it was helpful!
Joe the only thing that you did not mention is run a spider front and back of the head stock and indicate both the rear and front at the spider's .because if you have not set up the chuck the jaw's and or the scroll can be out there by given a false reading number one to level is to have perfect aliment with the spindle . just my 2 cents worth . :)
Thanks Joe. I have acquired a new to me lathe. Very excited about it and been pondering this leveling process. Very timely for me to see your video and thanks as it is making sense.
Great. Once the fog is cleared, its not so scary.
Simple and clear. Now we should all have true parts. Thank you.
Thank you Joe and This Old Tony
as well.
Am currently in process of doing this very same excersise after i manufacturer my adjuster feet for my lathe.
Thanks for watching Troy.
Great video. As an advanced beginner I could never understand why the lathe had to be "level". I always thought it was in relation to the floor and couldn't figure what difference that would make. Now I understand that level is actually better described as a type of twist. Luckily my lathe has always been "level" with no problems.
Great model, very clear to the the hobbyist.
Always a bone of contention, ref lathe leveling. You are levelling the lathe, to de-stress and align, using an accurate engineering level. Large lathe builders will grip a suitable diameter thick wall tube in the chuck, turn the OD with no steady or centre, and adjust level to minimise taper. Place level on the as turned of, this should now agree with the overall level reading. Your engineering or machinists level should have an accuracy of 0.05 mm per Metre or 0.0005" per 10", there are more accurate ones, but you can achieve a reasonable result on small sub 1 metre or 3 feet bed length with a 0.5 mm per Metre (builders level).
Thanks for sharing Joe, and best regards from the UK.
Lathe leveling on a ship is the same,
I heard someone say / write years ago about lathe "leveling"... There are lathes on battleships. Level by itself doesn't mean a lot. Twist and contortion ruins accuracy.
Precisely correct.
Thank you Joe for the intel I am going to check the alignment of my lathe again.
When you think about the word "level" just think of all the lathes that were and probably still are in ships, portable machine shops, etc.. They cannot maintain them in a "level" condition.. The twist and flex in the bed is much more important....I have a 1942 LeBlond trainer on which I set an indicator on a work piece between centers..Change shims under the feet and tighten the bolts slightly and watch the indicator needle move.. Mike in Louisiana
Lathes on ships have 3 feet, so no matter of the level it will never bend.
When I ret 11 years ago,my wife bought me a14-40 in. grizzly lathe. I know bought across the pound.I leveled it up,with a sterett prec. level like you inst., with the help of a 40 year machinist. I can hold .ooo5 with no digiital read out. .still 11 years latter . The old machinist still comes down on his walker to do his little projects ... Also no taper on a 2 ft. shaft It was below "o" in the garage had to reline it once. In warmer meather.. Wisc. winters
Some lathes (such as mine), the ways run all the way under the headstock, and the headstock rests on the bed like the carriage. These lathes have only 4 leveling points. So bed twist is the only thing needing worrying about.
Comment about headstock alignment: you really need to do the indicating UNDER the work on the tailstock end to detect bend, and indicate IN FRONT of the work to detect bed twist.
Thanks Professor Joe! Now I understand the geometry behind getting the lathe level.
Lathes should be mounted on a rigid base and the mounting tuned to make straight cylinders. On land gravity provides a reference. I have worked on lathes and other machine tools mounted on a ship. On a ship gravity is rarely perpendicular to anything.
I'm glad you had a great trip and have returned safe and sound! Thank you for the information about lathe leveling it's very useful! This old Tony's was useful too, but your example was spot on! Again Joe, Thank you sir!
The models really help. Thanks for watching.
Hi Joe thanks for your excellent video on lathe alignment . Regards Brian Johnson
That was a great video Joe. I would really like to see how you adjust the headstock on this lathe. From UK
Hey Joe, Ok thank for sharing a topic in these videos all the time. Lance & Patrick.
That was an awesome demo and explanation Joe! Thanks!
I think the reason they say "levelled" is because most people have something that will accurately repeat "level", but not everyone would have something that can accurately repeats 3.842*.
From what I gather from this, you should level the headstock first, Square up the headstock to the bed, make sure the bed is level near the headstock, make sure the axis of the head stock is level, and then adjust the feet on the end by the tailstock until that is level as well, and you'll probably have to go over it a couple times before thing settle in
Great video. I was in the process of refurbishing and setting up my lathe (until my recent health issues), and this will come in handy when I am back in my shop. Love the Clausing lathe.
Hi Joe, It's great knowing you guys are out there doing what you do to help guys like me enjoy what I do! TFS. G :)
Great well demonstrated video as usual Joe. I've also never been able to figure out why "lathe leveling" is so misunderstood on the forums. It really isn't that complicated for what needs to be done and why it needs to be at least checked. Using a decent machinist's level is just the easiest way to get the bed straight and parallel. Actual "level" as you said isn't even needed, it's just the quickest and most simple way to measure and adjust to end up at that non twisted straight and parallel condition. At a minimum the free online PDF of Dr. Georg Schlesingers book Testing Machine Tools should be required reading for anyone who owns or operates machine tools. Read through that enough to grasp the concepts being explained and why each test is being done. The equipment & getting any machine tool properly aligned then gets a whole lot more simple. The Moore Tools book Foundations of Mechanical Accuracy also gives some of the best diagrams of the causes of machine tool inaccuracy or misalignment and how it affects a machined part I've seen so far.
I'd also add that even getting a lathe perfectly dead level is still only a static condition. I've proved to myself that very minor final tweaking is almost always required due to the machines various parts flexing just enough under the cutting loads to make a measurable difference if your trying for the absolute best the machine can do. Then you do need to know which adjustment screw needs moving and in which direction to roll the cutting tip slightly into or out of the cut.
Plus they settle over time. Mine actually sits on high density rubber machine mounts.
@@joepie221 LOL, you have it easy. My shop floor is the usual wooden construction. I can get my smaller lathe than yours to turn perfectly parallel and two hrs later with a few changes in humidity or temperature it's turning a measurable taper. So I've had to do a whole lot of adjusting over the years. It's taught me a lot about that "lathe leveling" but the problem is obviously something I'd rather not have.
Nice, simple graphic. I like it! I'm a big fan of ToT too.
Aloha Joe, "great minds think alike and fools seldom differ" and my wife never would say which side I was on.... I agree with you completely, but have known few who agree with us. Most say level the ways then tweek the tailstock end to bring the taper out of your work, I never could understand, or agree with that. Now with the aid of your "state of the art" training aid it all becomes clear, I hope my friends were watching. As to the training aid isn't "modern technology" wonderful? Keep the great source of common sense coming our way. Mahalo nui loa. Aloha ke Akua.
The hinge point is probably more of a bow point, but the end result is the same. Hawaii was beautiful. I'd like to go back someday under different circumstances and do some diving. Kona night Manta ray dive ----- Bucket list.
Eye opener for me
Thanks Joe, glad business is busy
Brought my used lathe home
Put my level on it and it seemed to be perfect
But when i trammed a round straight piece between centers my tail stock is low
Moving the tail stock closer to the chuck reduces the error
Now this helps me understand it
I think its exactly like you are saying it is
Anything pinched between centers shouldn't show much difference as demonstrated. Don't rule out way or tailstock wear. if you want to tram the tailstock, do it with a long bar and indicator in a chuck. Don't use a bar that will sag.
Excellent video. I'm just getting into machining, have a 10" Atlas lathe, and I'm probably not going to get it dead on, but.....at least I know and understand now the hows and whys.
Excellent. Good luck and have fun.
Huge fan. So glad to see your back.
Thanks for your great explanations. You have improved the quality of my work twice fold. Thank you
Excellent. Thanks for the support.
Newbie to lathe work, Joe you’re a great teacher, no BS straight to the point and easy to understand. Thank you! I bought a second hand Grizzly G0750G lathe and I decided to bolt the cabinets to the floor and make adjustable riser blocks between the cabinets/stands and the lathe. My thoughts are, because the stands aren’t ground true it would be easier/faster to true just the lathe and not both cabinets & lathe. Is this method asking for trouble?
As long as the lathe is sitting on a surface rigid enough, it should be fine. If the machine is heavy enough not to walk around, or fall over on top of the cabinet it should be OK.
An inspiration as usual Joe, THANKS!
This really helped me visualise what is going on. Thank you.
Hi Joe, I also jack up the machine in order to minimize taper! I'm a bit afraid to do adjustments to the head stock alignment, as I cannot (easy) confirm or verified dis alignment from top or bottom. Now I got a half thou over a distance of two inch round stock , (diameter 2 inch) cutted direct from the head stock! (not between centers) I hope I can improve this, as I do cylinder boring over 6 inches, and after the boring operation, I still can honing the iron linor straight, but I prefer that it comes from the machine with minimum taper! Anyway, got again useful information from this video! Many thanks.
Thanks Joe, glad you’re back.
Interesting vid, kinda reinforces what I had thought about people rigidly bolting lathes down then trying to get everything level. I only have mini machines now so can use a long MT3 drill blank in headstock for checking and just haev them sitting on wood blocks
Thanks, excellent information. I knew Part I of the info (removing bed twist) but not about the head leveling. I'm cutting a noticeable taper on my 14x40.
I bet this helps. Good luck.
Hey Joe,
I concur, some folks search for to much information and the problem becomes blurred. Your video should clear that up.
Mike from Plus8Precision
... and by the way, many people don't have a precision level anyway. The South Bend manual defines a precision level as "sufficiently sensitive to show a distinct movement of the bubble when a 0.003" shim is placed under one end of it." A precision level is certainly a good reference tool to determine if the lathe is true to itself, but can you imagine a Machinist's Mate calling up to his commanding officer, "Captain, find me a calm sea and stop the fleet. I have to make my final cut."
You nailed that.
The mate speaks to his chief who explains to the OOD how it's done-
Master Chief reveals it's done with a theodolite-
Joe, Thanks for sharing. I always learn something new when I watch your videos.
Only 4 feet on my hobby size lathe! When I installed it I mounted a DTI on the tailstock, reading off the end of a 1Ft bar in the chuck, and made sure no deflection as I tightened the bolts down. As for 'level' I just made sure the whole assembly ( stand & lathe) tilted down towards the suds tray drain fitting.
I did not appreciate the longitudinal axis tilt of the head stock until now. I am now going to do some investigating.
Thanks again Joe, as per usual you have pointed out something else that we should consider, you mentioned about a round bar that you can measure from, what sort of thickness should we be looking for, would a ground bar be better (we normally use a 25mm ground bar by 600mm long to set up our A axis when we put it back into the concert). Thanks for your help, I for one feel like I have learned quite a few tricks from you that helps me out a lot! Thank you...Phil
Wow 45 years in the game and always learning thankyou
Wish I had known or realized this in 1981. Worked civil service Coast Guard in one of their Base Welding/Machine Shops. Had two old lathes, a La Blonde and a Southbend. The La Blonde had a wicked taper on the tail stock end and could Not figure out what the heck was wrong. Both were Pre WW II machines to give ya an idea how old they were & both off a Navel ship out of their machine shop on board. Well thank you for this old mystery clear up. Hint - was not a machinist - OJT all the way, was wielder by trade.
Yes perfect timing here to because tomorrow Iam setting my lathe! Thanks for sharing!
Thanks for the video, Joe. I must have missed this one last year and I need it now since I am rebuilding a 13 x 40 with 6 level adjusters.
Very clear video Joe, thanks for taking the time to make this. Best Regards Sarah
A few comments and questions:
As far as I can see, your ways looks bolted to the headstock.
To me it suggest, if it is true, that you can level your headstock as a unit, and then level your bed in line with that.
The 6 leveling feet you have on your machine, I have not seen in the now 12 different marks and models of lathes I have been in contact with, they all only have 4 levelers.
Also all the lathes I have seen, the headstock is bolted on top of the bed, and thus have to be shimmed to change the "centerline" according to the bed.
I am with you as far as you can, to some degree, level out warp front/back on a bed, but it means that you have to bolt down the cabinet to the floor, and many amateurs have their shop in a basement with wooden floor, at least in Denmark and Sweden.
Otherwise an very informative video as most of your videos are.
Timing. I have half done one of two lathes today at work. Monday I finish the jobs. Great demo.
Mine also have 4 bolts at the tailstock end. Never worked with that before.
I ran an 18-140 gap bed Mazak for many years. It had a center island on the bed because it was so long. Imagine how that came into play for the guys that set it up.
@@joepie221 I never got to see them but my father set up old ww2 lathes that made the barrels for big war ships when he worked with the dep of defence. That would have been one interesting experience.
I agree with @componenx. Having served on numerous navy ships, including a repair ship, I would say it could be mounted on the overhead, as long as the be is not twisted. I have my two lathes mounted on glue-up wooden bench tops (suggested by Atlas), and held down by two lag bolts through the from legs, allowing the rear ones to float. Works fine for me.
Excellent Joe. Now, could you go into how to tell if your taper is caused by a twist or head alignment?
"Level" is used because using a level to set up alignments is the easiest thing to do. It is the easiest way to use the tool involved. Trying to set the lathe to be aligned to a 20deg inclined plane would be more challenging using levels especially since as you tip a level over it becomes inaccurate due to the curve in the glass that forms the bubble. It is also possible if you install a lathe very much out of level you could have lubrication issues as the oil level in all components was designed for being on the "level".
The confusen for new to the trade is probably that the three main reasons for leveling was not really well explained in perspective, like for fluid requirements, heavy weight requirements and the culprit the ways to headstock alignment assist.
Hi Joe. Thanks for being reminded of this.
Thanks for the facing tip for checking headstock alignment!
Its quick and effective.
Great explanation! Knew about leveling my lathes, but not about headstock alignment.
Putting the level on the top of the ways is an assumption that the top of the ways are true to the load bearing section of the ways.
Since we are measuring bed twist and not level I feel it would be more advantageous to put the level on top of the cross slide.
Then move it from one end to the other.
You can look at the load bearing part of the ways as the supplier and the cross slide and tool post as the end user.
The end user is what you want to check, not the top of a V way that has no function other than to take up space.
All this assuming your ways aren't worn out which seems to be a growing problem with older lathes.
Agree. In Sweden we talk "technical surfaces." Some take pressbrake tooling, use the outside as distance blocks and I tell them they are not true. They say they are true to the thousands and they are but only on the technical surfaces.
Another thing to be checked is the horizontal alignment between the head stock spindle axis and the bed. This isn't a common problem on lathes where the head stock actually sits on the bed flats and V-ways. The head stock is scraped in at the factory. That said, if it is out of specification, the only cure is to remove the head stock and re-scrape it to fix the misalignment... not a job for the average machinist to do. This is a task for a machine rebuilder.
Where it can be a problem is on the smaller Asian built lathes. The head stock doesn't sit on the lathe V-ways and flats, but sits on a flat machined surface under the head stock. The head stock is bolted to the bed with four bolts (usually) and there are two horizontal jacking screws on an overhanging lip on the back side of the head stock. The good news is if alignment is called for, the head stock can be shimmed for vertical alignment and the jack screws can make adjustments for horizontal misalignment.
This is also the time to make sure the tail stock quill and head stock spindle center lines are the same height. Also make sure the tail stock quill is parallel to the bed both vertically and horizontally. Faults in this area show up when drilling very small holes. You will notice the drill flexing to pick up the center of the rotating work because of misalignment and moving the tail stock side to side won't cure the problem.
If you have an inspection sheet for your lathe, use that to inspect the lathe's condition and make adjustments as necessary. Many of the older handbooks give general alignment specifications for tool room lathes if you don't have specific tolerances for your machine.
Cheers from NC/USA
I can't wait to 'level up' my newly acquired Clausing 5912
Your video 'demystified' the Clausing manual leveling section
Thank you
Fantastic explanation of what is going on in leveling; thanks, Joe.
Glad it was helpful!
Thank you. A great explanation of lathe geometry. I will be checking mine now.
Straight is important , but level is extremely important in a job shop for set up of odd ball parts esp line boring & assisting with steady set up's on long shafts . Cheers .
Maybe a better term to use instead of "level" would be "True?" As long as the head stock and bed are parallel / perpendicular is the key since the term level is relative to so many factors especially mobile machines in ships etc.
@@robertoswalt319 A spirit level is sometimes used in job set up when indicating is not a complete option , like with some face plate work .
@@swanvalleymachineshop When I commented to the term level in my comment, I wasn't referring to spirit levels. I was commenting on the topic that Joe brought up about how the term "Level" had been, in his opinion, too broadly used. Many seasoned machinists will say that a machine doesn't have to be truly level as long as the bed is true to the plane the bed resides.
I agree that spirit levels are often a good choice when trying to get a part set up.
people dont think cast iron will bend,twist,warp. but. it WILL do all this stuff. alas is true. the phrase should be relativly inflexable. when you think of the fact that "most" machines are
"seasoned" cast iron. the soaking pit changes iron! poppy
Joe
When people say they have levelled their lathe and not done any accuracy checks just make me ROFLMAO.
Then I ask them why is it important to get it level to the big ball we live on
Yes it can help on a mill to set up a job
Then I ask them how do you level a lathe on a ship ? As you know the do have machine shops on board ,certainly not at sea , could it be done on dock maybe , dry dock again maybe , is the ship floating level I doubt it very much
but as you say the lathe must be true to itself , and be without stress , if it’s set up that way to be truly level to the big ball matters a jot
keep up your very informative vidieos
Now I must get down to the WS and get the concert mill warmed up and make some parts for my miniature triple expansion engine , while that doing its stuff do some bits on the manual mill , lathe work to come later 😀
@ Joe Pie This is precision seeker's gold.I don't know how I wasn't able to see this video before. Thank you.
Glad you like it.
Harold Hall outlines a nice procedure in his Lathework book on cutting a cylindrical square as a test for headstock alignment. On the (tiny) Taig, I was able to get within a tenth. My newer 13x40 Colchester clone was close enough without adjusting the headstock, fortunately, since while it has better provisions for adjustment, actually getting at them requires a lot of fiddling.
Thanks Joe for explain lathe alignment so us armature's can understand ! PAul in PA.
just what I wanted, clear and concise: thanks.
That's a great presentation. I see a lot of cases where a machine mover contractor hires another contractor to
laser the machine and comps it out to be "straight", instead of physicaly leveling the machine. The people doing that have no clue what to do to make it right. All they do is introduce stresses into the frame castings and allow the machine to get bent.
On large CNC machining centers, the head is fixed and the column is rigid. You actually have to tweek the level of the table with the machine feet to indicate the spindle. reverse procedure, but the only way to do it.
There is a long list of different kinds of design when it comes to machine tool machinery. The good ones are heavy and rigid with a properly built foundation and no soft feet. I'll take an old American design like a Producto, Gray or Cincinnati Milicron that has replacable ways over anything imported with ways machined out in the frame like a Mazak Y, or YB. Too bad that most domestic machine tool makers have been sold and no longer in operation. I look at it from maintenance prospective because thats what I do for living. Older designs are easily upgraded with modern controls, but sometimes the people who make the decisions to purchase equipment don't have a clue what's good.
Outstanding, explanation and especially the bit about "Leveling" the lathe which is a very misused term.
Another great presentation. Thanks.
Newer lathes present another problem. The headstock does not locate on a V way. It has jackbolts to align the spindle centerline with the centerline of the bed. How about a short video addressing that adjustment?
Headstocks aligning on the Vee are the suck.
level the bed to remove any twist. Put a 3" diameter aluminum pipe 14" to 16" long in the 4jaw, and make test cuts with a shear tool, and measure the diameter at both ends. If you need to align the head stock, keep in mind it will shift when the bolts are loosened. So put an indicator at either end of the tube before loosening the bolts. Once the horizontal alignment is complete, sweep the top of the tube to verify vertical alignment.
I disagree with Joe on the importance of vertical alignment, it has to be way off before it has a meaningful effect on the taper. This is just simple geometry. Fire up Fusion 360 and check for yourself. For example, if the headstock points up 0.050" at 12", the result will be about 0.0008" taper. The smaller the diameter the bigger the affect. 0.015" mis-alignment will give about 0.0009 taper.
Please point out at which part of this video, I said vertical alignment wasn't important. i think you misinterpreted something.
You addressed vertical alignment very well. Not discussed was the use of jacking screws to shift the headstock front to back. I know hoe to do it with a 2 collar test bar held in the chuck. I am betting there are a lot of viewers who could have benefited from that discussion.
Similarly, when I worked in pre-press layout dept. (stripping dept.) at a printing company, we had 60” T-squares that would ride on a straight edge on the side of a 4’x6’ light table. You would tape two pins down to the glass of the light table using the T-square and all the acetate sheets would be punched and register to those two pins. These T-squares were solid stainless with a machined steel head attached solidly with screws. A precision piece.
I started in a new shop and one of the journeyman lay-out men, yes, we called ourselves strippers, would, for a small fee, take your T-square home and “calibrate” it. I.e. knock the head on the floor to get it EXACTLY 90º.
I was the new kid, around 25, but had been at it for 7 years or so, and he eventually got around to me. I told him no thanks, that the angle being 90º was not important since we attached the pins to the table using the T-square and as long as it was solid and you did not switch T-squares between the different taped down register pins everything was cool. All that mattered was that all the lines stayed parallel. He argued for a while but eventually gave up. I don’t know if he ever figured it out.
This will make life so much easier for all those '60s Batman villains. ;) Glad you got to enjoy the business trip as well. Thanks again.
I'll probably go back for the Kona night manta ray dive. Its a bucket list item for me. Look it up on UA-cam. Amazing.
Thanks for the vid! I have a large Monarch I need to level, (woops I meant get into the same plane) and now I know a far better way to go about it!
I have read several comments about the test bar deflecting up to and including using a ceramic test bar to prevent it.
There is no reason to worry about a test bar deflecting from it''s own weight.
There is a simple way to test for deflection.
Set bar on flat surface set one end on something of known height and square and measuer with other end hanging out.
anything can be used around the shop to do this including two tool bits of same thickness to two round bars or anything as long as it's square or of the same thickness.
You dont have to break the bank buying stuff.
Say the pedestals you have the bar on are 1/2 inch and the bar is 1 inch.
If the bar is deflecting you will see it when you measuer, the end supported will be 1.500, the hanging end will be less.
Which it wont be but test if you wish, at least you will know.
"Which it wont be but test if you wish, at least you will know"... "There is no reason to worry about a test bar deflecting from it''s own weight"... Do they omit tuition on the subject(s) of Airy and Bessel points at engineering colleges nowadays? At the very least, you must have had the Airy points on a precision straight edge pointed out to you in the metrology / mensuration module? Deflection's real, but often immeasurable and immaterial in the normal workshop. www.engineeringnotes.org/metrology/airy-points-and-bessel-points/ Most of us spend our lives in "normal" workshops, but if you visit places where gas or steam turbines are made, or car components, or gauges such as Johansson blocks, or antifriction bearings, or precision machinery, or gauging systems are made, where temperatures, air quality and humidity are closely maintained, and where even fifty and more years ago, air gauging systems were measuring to millionths of an inch www.qualitymag.com/articles/88856-quality-101--all-about-air-gages
Your flat surface? how flat? Guys use ground plate, assuming it's flat, forgetting or not knowing it won't be, as can be proven with a diffraction grating interferometer... Energize and clock a magnetic chuck or table with a tenths clock in both planes, at 1/2" intervals It'll not be flat. Surface plates and marking plates are often confused (unless you get the bill, and see the huge difference in price...) Your mandrel? (bar) how round? It's a surprise when the Talyrond is applied to a newly ground, "perfectly round" workpiece, and you find the trace is like a ploughed field...
It's all a matter of degree, but awareness of the more esoteric engineering phenomena can make a huge difference at interview if you're seeking a move into a better class of engineering work (which may be a retrograde move, causing more headaches and paying less) I was aghast at the rate I was offered for toolmaking work, in the seventies, so I took a job on maintenance. Rough and dirty, but the pay and freedom from stress...
@@robertlawson8572 We have a winner. LOL
Great video Joe. Thanks!
Nice bit of information Joe, now I just need the time to checkout my lathe.
My lathe (Maximat 11, 11' swing x 24") lathe has the ways project all the way under the headstock, so in effect, the headstock "sits" on the bed like the carriage & tailstock. There are only 4 leveling screws, 2 at each end, so bed twist is all I need worry about (or can do anything about). On larger lathes, the bed usually gets "super thick" near & under the headstock to resist the deflections you are concerned with.
Have you measured your lathe, or tried to make these errors happen, to note their severity?
MANY MANY THANKS!!!.. Joe I have spent years in the same discussion with bosses and co-workers. "LEVEL" has to do with the Earth...focus on straight-square-parallel -and dimension...etc. When I see people grab a carpenters level...glance at the vial...see anything of the bubble...then yell..."it's Level!!!" Kills me...or the next best..."Level the part" then machine it...yea....how about the status with the machine and the Earth first..... Those boxes are the best working model of the complexity of an Engine Lathe. Thank you Joe! Keep it up!
The will be slight exceptions and maybe some bowing, but overall the boxes really represent whats going on. Thanks for watching.