Over 50 years ago I ran a Thompson grinder very much like that one, the hydraulic pump whined the same way until the boss had me rebuild the pump. The race that the vanes (Vickers vane pump) run in was worn with chatter ridges, replaced it and the vanes and the whine went away.
Back in the early 80`I ran a 20` Thompson surface grinder in a job shop. Some of the work we did was the angle plates for j c Busch. Did ones up to 4 feet tall square to 2 tens per foot.
Just a quick thank you Keith - I really appreciate what you do. I recently got a load of vintage equipment: a DOALL ML, DEWALT G55, Landis 618, Bridgeport Round Ram and BREDA BRF 150 and your manual archive is 5 for 5. Thanks so much! I will definitely subscribe to Patreon.
Five days after carpal tunnel surgery you are out in the shop that’s impressive . Took me several weeks before I felt like doing anything stay healthy we All enjoy your videos
I can hardly wait until I see my own Mississippi square!! Well done! I know now why all the old timers I knew didn't put up with anything. They were tortured at night by nerve pains. My carpal issues would wake me at night with a red hot ice pick feeling. I didn't have much tolerance during that time. Amazing how a few years will give you better perspective.
if you have carpal tunnel the diagnosis is if you shake your hand down like shaking down a thermometer. if that is the case you should get the operation like I did. any questions on the procedure I can let you know interested.
@@jaysilverheals4445 Thank you! I got mine done late 2019. Thankfully, the nerve conduction study didn't find any issues above the wrist like Keith. It has been a real game changer for me. I can sleep now, and grip with that hand too.
Wishing you a speedy recovery,I really enjoy your videos my dad worked in a machine shop that made parts so I am learning something about what he did for a living.
For best results when surface grinding, wheels need to be balanced and trued - two distinct and required preparatory processes. Small machines have small-diameter spindles, and are likely MORE sensitive to wheel imbalance than large machines. The very common Sopko adapter
I would suggest 20 to 30 thou step over for finish cuts. Also only 5 tenths or less depth of cuts. And as many others have said some spring passes. Heat also has a large part to play when trying to get flat, parallel and perpendicular within tenths. Although with the coolant that should mitigate most heat issues
Hey Keith I've been watching for quite a while and I don't think I've ever seen this Thompson grinder what an amazing machine You need to do a whole video on it!! I mean built in cluster diamond wheel dresser come on I want to hear all about that!!
Keith, we had a place nearby that had some grind wheels like that, but no hubs. They had some wheels that were kinda' like a dense Scotch Brite. They are gone now, but for the life of me, I couldn't think of a single use for them.
@@johncoops6897 that was my thought. I'm not sure what the company did with them. They had them for quite some time. They decided to scrap all of their used or otherwise fasteners, so who knows what happened on the grind wheels.
A Thompson grinder very similar to this one sold recently in my area for $270. I was considering bidding on it, but noticed that the guard/truing assembly was missing. It's also twice as big as my current grinder...
Right hand Carpal tunnel and ring finger trigger lock surgery last spring. I was down 3 months. Last week had left thumb joint reconstruction, 6 - 8 weeks in cast. then 6 - 8 in brace. I'm bored stiff, can't do nuthing. The real bugger is right thumb reconstruct is next followed by carpal on left. take care get better. Update: I bloodied my nose trying to scratch my nose with the hand in cast.
Slower side-to-side travel and finer front-to-back increments between passes does a lot to improve surface finish. How much is your downfeed each pass? For ultra-fine finishes, I will run a couple "spring" passes with no additional downfeed; stop when it sparks-out. If I were the owner of these squares, I'd have painted (powder coat) them before starting so the web would be protected.
A bit off-topic and pretty irrelevant trivia, but that sound the machine makes @ 12:06, when lifting the head, is exactly (if my aural memory serves me) like the sound made by the "dynamo" used for charging the battery in the lighthouse in Stoneship Age in the original MYST game.
It's better to use the magnetic placement for the diamond dresser. The "on machine dresser" introduces side play vibrations....Anyway I appreciate and enjoy what you. Thank you
wheel dressers are the best money makers there are however he does not have much experience with them. diamond on chuck is best but will run a shop out of business.
Nice job Keith, I always learn things watching your videos. One question on the inspection following the square-grind process. You used your magnetic transfer block as a riser, and explained that because it was the mate to the block used on the grinder and that it may introduce some error. If your 6X6 block is the gold standard, why didn't you just hang the tail end of the square off the edge of the surface plate and eliminate the riser block entirely? Obviously, you need the block for the grinding operation, but for inspection purposes wouldn't this have been simpler? Thanks -Kurt
At about 6:30, you refer to your "clamp kit". Is that something that is commercially available or did you create it yourself? I've been looking about for something like that but have found nothing so far.
Had the ulnar nerve release in both elbow after 37 year career as heavy duty mechanic sometimes wonder if I did right thing after small and ring fingers were clawing over retired after elbow pain just too much still struggling 10 years later
Over wheel dressers are great if your grinder has no wear in the column. If you try to dress with worn column the wheel is true to the column not the magnet which is not ideal.
Could you have used your cylinder square to verify the squareness once you got done with the grinding? Also, how does one determine how fast the feed is for the surface grinder? To a novice like me, it seem to be moving very fast.
The way you touch off is not wrong but I touch off a little bit differently. With the wheel off and over the work piece I turn the wheel by hand and slowly feed down till the wheel just drags against the work piece. Also making sure the work relatively straight. For me I have less surprises. Balance wheel depends on how stiff your machine is. The Cincinnati no.2 I never needed to balance any wheels but I work a Dakota model KO lee and l have to balance almost every wheel. The difference is the Cincinnati no.2 is about 2000 lbs and the KO lee is about 1200 lbs . Makes a big difference. With the finish your getting I wouldn't worry about it.
After watching various vids about surface grinders… And the effect of magplates bending the workpice… I was wondering how much this setup, clamping on the thin web between the legs would distort the pice… my thought was that clamping maybe should have been done on the legs themselves? Any comments on that? But maybe these effects are far to small to be noticed on this part?
@@paulcopeland9035 I phrased that poorly. I was suggesting that Keith put the square directly on the surface plate and use the squareness comparator to check the accuracy of the newly ground square without the fixtureing that could be introducing some error.
I'm guessing he made most of it. The toe clamps aren't hard to make and "T" nuts aren't hard either. For the rest it's just hardware store nuts and bolts. I've made most of that stuff for myself although I don't have the cool box he's got you can get them from Canadian Tire, (in Canada), and I suspect Harbour Freight in the US.
Joe Pi made a set of these as well as a mini fixture plate....I copied his design and made the same set, use them all the time. If you want a Fusion360 design/print, send me a PM and I'll shoot you a copy.
Balancing isnt worth the time IMO... I run grinders for a living we buy pre balanced wheels from norton and they are plenty close enough no one at my work balances wheels I'm still able to get sub 8ra finishes easily. Also I think your surface finish issue with that SG wheel was dress speed... if you watch the video you dressed extremely fast with the sg wheel using hydraulics and a lot slower with the SC (silicone carbide) wheel... any of those wheels will give a good finish it's just more of how well it cuts and how much stock removal you can get done in between dress cycles... just my 2 cents...
Just a hobbyist, but will not the surface grinder wheel change diameter when grinding , thus not keeping the distance to the workpiece exactly the same, or does these machines compensate/ indexing somehow for this change in diameter / distance to the workpiece while grinding. Just curious.
So... if you need a square-ground fixture to grind the square, and known-squares to inspect the squareness, how was the "primordial" known-square made and verified in the first place?
you simply step grind it dead nuts. that is how tooling is made square from scratch. not by purchasing an item assumed to be square. his method to check the squareness after--------------------was simply wrong as his tenth indicator showed.
@@mzb8134 Thanks that was an interesting read! But my question was about the perpendicularity not the flatness. Found a book that explained how to reach the squareness from the withworth 3 plates: it's using a box with 2 opposing sides, flat and parallel, then the perpendicular side is made flat, and checked with an indicator and bumper with itself by reversing the box. (After setting the indicator to 0 on one side then flipping the box the indicator will show the double of the error in perpendicularity of the face)
Same base material, However these are then ground the same way as he is grinding that square so the the mating surfaces are as close to dead flat as they can be. Unlike the out of the box versions that are sort of flat.
So, one thing I've never quite understood about surface grinders: The wheel gets smaller every time it's dressed and used. How does the machine adjust for that?
The stone is always referenced to the work by light contact establishing a relative zero point. Then you remove the amount of material by lowering the stone from that zero point. You measure the workpiece directly, more than once as you remove material, and as you grind it the reference surface becomes more uniform and accurate. Lastly you work towards the final grind with a freshly dressed stone and light cuts after once again measuring the height and zeroing it on the surface you are grinding.
@@Bakafish ah, okay, so if I touch off, then let the head come down 5 thou, and let it run over the piece until it stops cutting, then I can reasonably assume I've taken 5 thou off the piece?
The wheel stepover sideways while grinding is a fraction of the wheel width so the wear doesn't make difference within one pass as the wear happens mainly in the leading corner of the wheel. Otherwise the wear is not an issue either, except for cnc machines where the machine needs to know the wheel size after dressing
Surface grinders are a mystery to me. I know the stones are different, they are cooled and the cut depth is small, but it just seems that the stone goes away a bit at a time and would lose accuracy. Just my insanity thinking out loud here. I had carpal tunnel surgery in the right hand about 20 years ago. Wasn't able to take time off the job long enough and was on it again within a week. Wasted procedure (like the surgeon said) it reversed the benefits of the surgery. Been living with it since. One of the hardest things for me to do for example is to find a screwdriver at my house, I don't have many because I have to use power tools for nearly everything so hand tools are always hiding, but I get by.
The wheel has thickness. Only the leading edge is eroded, by the time some is worn away there is more waiting as the cutting edge travels across the width of the cutting face. The diamond dresser is used to resquare the cutting face, and the process starts again. You have to wear out the entire face before any potential error is introduced, but used correctly, that will never happen. So it is one of the most precision processes we have.
@@Bakafish Ok, so you dress the wheel for each job basically. That makes sense as well as the leading edge wearing and the trailing surface finishing to spec. Thanks
@@marcp1180 Yes you dress the wheel, then start grinding, you make a pass and then check the stone, if you managed to run across the entire face, you redress the wheel. However that rarely happens because you don't normally remove a lot of material during this process. The idea is to machine it to within a thou or less over and then grind it to final size if at all possible.
@@Blazer02LS Thank you, I'm a small time hobby machinist and grinding wasn't any part of my learning experience. Thanks to y'all for your knowledge and for Keith bringing on a good video about it where I'd get the chance to ask.
@Sunlight through a window I think it was Project Farm that shortly ago did a comparison video of a few different brands of screwdrivers. The Harbor Freight screwdrivers quite shockingly did very well against many of the other expensive brands. You may just be doing people a favor by loaning Harbor Freight screwdrivers out.
Hey Keith. Would it not work when measuring the surface to turn it 180° and it should be out by the same amount in the other direction if these parallels are not exactly parallel. It's how you check a carpenter's level turn it 180° on the surface and if it's out by the same amount the other direction then the bubble is on. Actually the way you did it is correct I believe. If it's out by the same amount on the same end on both services then they should be 90° to one another
Hey Keith! I'm interested in your precision grinding blocks, do you true them up? I am always flattening sharpening stones, but I think you would need at least three surfaces to guarantee flatness. my concern is that the precision grinding blocks may well be out if true of you only reference them against eachother. I know it wouldn't matter for your end result here, cool that you have a special set of abrasives for this sort of thing. My stones for knives wouldnt cut it.
I don't envy you for getting carpel-tunnel surgery, personally I was lucky enough to avoid it. I had it years ago. I was crawling under my house in the crawl space, working on a frozen drain. I moved a hot water pipe out my way, and didn't know there was a crack in a 220V wire. I got the jolt of my life, ended up with an electrical personality, but poof! carpel-tunnel gone and haven't had a problem since.
If the "precision block" is square, flat, and parallel to 50 millionths, why isn't the square you ground square to within 50 millionths? Where did the error come in ?
I think you could have gotten a more accurate, or at least more easily readable, 6" measurement by using a tenths indicator on a stand (like you used on the surface plate) and a 6" gage block as a setup piece to zero the indicator. Any difference off zero would have been a difference off 6" height.
Sir, unless you get super lucky, you'll probably be making hubs for your surface grinder, looked in usual places, and used different key words, nothing, notta, not 1 that even remotely looked close, but would make a great video, hope you get feeling better after surgery!!!
Keith I'm just asking a question Sir. By stoning the surface like you did to remove the Burs, 'wouldn't that in it's self change the Squareness / Flatness of the Plane of the Square? Also, by Clamping the Square like you have shown getting ready for Grinding Surface for Squareness to a Flat Plane also take it out of Flat and Square after releasing from clamps? Wouldn't it have been better to use a Electro Magnetic Lock Down to hold Part while Grinding? What about Room Temperature? Temp would also change how Flat a Surface is, does it not? How do you control this? Thank you Sir for sharing your vast knowledge with me. It is Appreciated.
These were soft cast iron squares and as such probably intended for utility work , I imagine if he was doing hardened steel precision inspection squares the technique would be different. That said, for DIY cast iron squares I would want to hand scrape them “Its the not the Destination, It's the journey.” one can buy a finished import square for less than the raw casting. Also a precision ground stone is to a "stone" as a concrete mason's steel trowel is the the dozer that prepared the site. As the grains of the ground stone have had their points ground off there is no clearance angle and they really don't cut a flat surface to any appreciable degree, only burs that stick up can get sheared off or burnished down
@@jaytalbot1146 Well thanks for your explanation. I do really Appreciate it, but I was really wanting Keith to explain because he was the Man doing the Job.
@@kennedy67951 ....You would be waiting a long time. Keith says he reads the comments, but I don't remember if he has ever answered or commented. He has a full time job and (like a lot of us) time is limited.
The concept behind precision ground stones is that (1) all the abrasive grains have been flattened on their tops, so essentially what you end up with is a precision flat surface with crevices in it, and (2) burrs sort of get caught in the crevices and removed with a high concentration of pressure on a very small area, and (3) once they're gone, you have a flat stone surface against a flat stock surface, and the pressure is spread out over a large area, no longer sufficient to do any cutting. So it's a simple convenient way to remove the dings without cutting into the base surface. As far as "oops," I think the major one is that when he originally set up the machine, I don't think he ever confirmed that the ways were straight, and I don't remember him saying that he ground in the top of the magnetic chuck to make sure it was parallel to the motion of the ways. In other words, he could be cutting a right angle that's tilted by the chuck surface, and depending on how he orients when he flips the fixture 90 degrees, possibly twice the chuck surface's error angle in the long direction. Maybe he did mention it and I've forgotten; I forget everything! I love Keith, and I'd bring anything to him if I needed it done quickly and "good enough", but he doesn't ever seem to have the time to dig down into the minutiae that really brings precision. I suspect it's a combination of a ToDo list that's a mile long, and then that makes it hard to have time to learn more about precision practices. I think he could do it... in a different world! :). Priorities, son -- priorities. :)
Over 50 years ago I ran a Thompson grinder very much like that one, the hydraulic pump whined the same way until the boss had me rebuild the pump. The race that the vanes (Vickers vane pump) run in was worn with chatter ridges, replaced it and the vanes and the whine went away.
Please keep in mind that, like the machines you restore, we all need a little maintenance. You are valuable to us !!
Wasn't in no hurry, going to use them in the shop for set-ups. Thanks so very much!
Now, that's a surname you don't see often!
Back in the early 80`I ran a 20` Thompson surface grinder in a job shop. Some of the work we did was the angle plates for j c Busch. Did ones up to 4 feet tall square to 2 tens per foot.
Just a quick thank you Keith - I really appreciate what you do. I recently got a load of vintage equipment: a DOALL ML, DEWALT G55, Landis 618, Bridgeport Round Ram and BREDA BRF 150 and your manual archive is 5 for 5. Thanks so much! I will definitely subscribe to Patreon.
I've had the Carpal tunnel surgery in both hands, It changed my life. Good luck with your recovery
Hi Keith, hope you have a speedy recovery!
Five days after carpal tunnel surgery you are out in the shop that’s impressive . Took me several weeks before I felt like doing anything stay healthy we All enjoy your videos
Man. I'm super jealous of your shop setup. I like your channel. Appreciate you passing on your know how. Thanks.
I can hardly wait until I see my own Mississippi square!! Well done!
I know now why all the old timers I knew didn't put up with anything. They were tortured at night by nerve pains. My carpal issues would wake me at night with a red hot ice pick feeling. I didn't have much tolerance during that time. Amazing how a few years will give you better perspective.
if you have carpal tunnel the diagnosis is if you shake your hand down like shaking down a thermometer. if that is the case you should get the operation like I did. any questions on the procedure I can let you know interested.
@@jaysilverheals4445 Thank you! I got mine done late 2019. Thankfully, the nerve conduction study didn't find any issues above the wrist like Keith. It has been a real game changer for me. I can sleep now, and grip with that hand too.
Good luck on the surgery. Hope it turns out well.
Hope you heal well!
Thanks Keith.
Great job Keith, take care of those hands, in our line of work we really need'um, great video, keep'um coming..
Great job Keith
Thanks for all the effort you take to post the work that you do. I always enjoy watching and learning.
I can relate. Hope you have no trouble recovering. I am nervously looking at having cubital surgery on my right elbow as well in the near future.
Wishing you a speedy recovery,I really enjoy your videos my dad worked in a machine shop that made parts so I am learning something about what he did for a living.
Great marking off table Keith.
Hi Keith,
It is good to see the Solid Rock tools being used. I can see you really love that new to you grinder.
Steve
Steve! Great to see you around sir, hope all is well!
Oh to have a grinder. How satisfying to be able to grind parts so accurately. Thank you for sharing. 👌👏👏👍😀
If anybody can do it it's Keith... Super nice work as always.
nice grinder!
Another brilliant job completed 👍
Silicon carbide is always the best wheel for iron. Good choice to swap it out.
Amazing the precision that is achieve able
Feel Better soon. Another project coming up, making hubs for the grinder 😀
Thank you for sharing. Watched it and very much enjoyed it.
Also, dressing the side of the wheel helps substantially. Improves finish.. Helps in the initial balancing also. Thanks, -Tom
Yes, that's all we used to do
For best results when surface grinding, wheels need to be balanced and trued - two distinct and required preparatory processes. Small machines have small-diameter spindles, and are likely MORE sensitive to wheel imbalance than large machines. The very common Sopko adapter
It's interesting how much the process you're doing is similar to how they make telescope mirrors.
Hey Keith, William Sopko & Sons should have your arbors, but hang on to your checkbook.
I would suggest 20 to 30 thou step over for finish cuts. Also only 5 tenths or less depth of cuts. And as many others have said some spring passes. Heat also has a large part to play when trying to get flat, parallel and perpendicular within tenths. Although with the coolant that should mitigate most heat issues
Had both my carpal tunnels released. Totally fixed the problem. Hope it does with you too.
Hey Keith I've been watching for quite a while and I don't think I've ever seen this Thompson grinder what an amazing machine You need to do a whole video on it!! I mean built in cluster diamond wheel dresser come on I want to hear all about that!!
Good morning!
Great job
Awesome! Thanks for sharing!
Keith, we had a place nearby that had some grind wheels like that, but no hubs. They had some wheels that were kinda' like a dense Scotch Brite. They are gone now, but for the life of me, I couldn't think of a single use for them.
The wheels might have been intended for linishing materials like Stainless steel with a linear and consistently fine scratch pattern.
@@johncoops6897 that was my thought. I'm not sure what the company did with them. They had them for quite some time. They decided to scrap all of their used or otherwise fasteners, so who knows what happened on the grind wheels.
Lucky Squares, “they are nicely stoned”, when do the munchies start? Keith caters for a vast audience, job well done.
That there is precision. Boing style. I would have liked to see the inside edge touched up a tad but still great work.
A Thompson grinder very similar to this one sold recently in my area for $270. I was considering bidding on it, but noticed that the guard/truing assembly was missing. It's also twice as big as my current grinder...
Good job thanks for sharing
Hiya Keith
Good morning to everyone.
Hope your enjoying lite workout!
Thanks for the video. Good luck with rehab....use the Cinderella principle: not to much, not to little
Don't you actually mean _"not _*_too_*_ much, not _*_too_*_ little"_ ??
Right hand Carpal tunnel and ring finger trigger lock surgery last spring. I was down 3 months. Last week had left thumb joint reconstruction, 6 - 8 weeks in cast. then 6 - 8 in brace. I'm bored stiff, can't do nuthing. The real bugger is right thumb reconstruct is next followed by carpal on left. take care get better. Update: I bloodied my nose trying to scratch my nose with the hand in cast.
Slower side-to-side travel and finer front-to-back increments between passes does a lot to improve surface finish. How much is your downfeed each pass? For ultra-fine finishes, I will run a couple "spring" passes with no additional downfeed; stop when it sparks-out.
If I were the owner of these squares, I'd have painted (powder coat) them before starting so the web would be protected.
A bit off-topic and pretty irrelevant trivia, but that sound the machine makes @ 12:06, when lifting the head, is exactly (if my aural memory serves me) like the sound made by the "dynamo" used for charging the battery in the lighthouse in Stoneship Age in the original MYST game.
It's better to use the magnetic placement for the diamond dresser. The "on machine dresser" introduces side play vibrations....Anyway I appreciate and enjoy what you. Thank you
wheel dressers are the best money makers there are however he does not have much experience with them. diamond on chuck is best but will run a shop out of business.
I just bought a 17 leblond regal lathe is that a pretty good lathe it needs motor n a good cleaning but where's a good place to get parts for it.
Nice job Keith, I always learn things watching your videos. One question on the inspection following the square-grind process. You used your magnetic transfer block as a riser, and explained that because it was the mate to the block used on the grinder and that it may introduce some error. If your 6X6 block is the gold standard, why didn't you just hang the tail end of the square off the edge of the surface plate and eliminate the riser block entirely? Obviously, you need the block for the grinding operation, but for inspection purposes wouldn't this have been simpler?
Thanks
-Kurt
Keith, did you try Sopko in Cleveland for hubs? Not sure they have your hub style, but worth a try.
At about 6:30, you refer to your "clamp kit". Is that something that is commercially available or did you create it yourself? I've been looking about for something like that but have found nothing so far.
Good morning from SE Louisiana 25 Oct 21.
KEITH, PET THE CATS AND DOGS FOR ME, TELL EVERYBODY HELLO, GREAT VIDEO, GREAT JOB...
Had the ulnar nerve release in both elbow after 37 year career as heavy duty mechanic sometimes wonder if I did right thing after small and ring fingers were clawing over retired after elbow pain just too much still struggling 10 years later
5:30 Anyone else hear the opening chords of Rainy day women no. 12 & 35?
Super machine!!
Yep, sometimes you have to step back and take care of health. You'll be back to pitching 90mph fastballs in no time Keith!
Why didn’t you use the squareness comparator to check the squareness?
Over wheel dressers are great if your grinder has no wear in the column. If you try to dress with worn column the wheel is true to the column not the magnet which is not ideal.
Must be and optical illusion- looks like it is going up and down especially when it get off the side
Could you have used your cylinder square to verify the squareness once you got done with the grinding? Also, how does one determine how fast the feed is for the surface grinder? To a novice like me, it seem to be moving very fast.
The Block you got from solid rock machine shop was .00005, but what about the block you had it sitting on? and what about your mag chuck?
What are the hub dimensions that you need? I have several extra hubs from a Reid surface grinder.
The way you touch off is not wrong but I touch off a little bit differently.
With the wheel off and over the work piece I turn the wheel by hand and slowly feed down till the wheel just drags against the work piece. Also making sure the work relatively straight. For me
I have less surprises.
Balance wheel depends on how stiff your machine is. The Cincinnati no.2 I never needed to balance any wheels but I work a Dakota model KO lee and l have to balance almost every wheel. The difference is the Cincinnati no.2 is
about 2000 lbs and the KO lee is about 1200 lbs . Makes a big difference. With the finish your getting I wouldn't worry about it.
I have those same tunnel issues, I’m curious how the surgery works for you, please update us later.
After watching various vids about surface grinders… And the effect of magplates bending the workpice… I was wondering how much this setup, clamping on the thin web between the legs would distort the pice… my thought was that clamping maybe should have been done on the legs themselves? Any comments on that? But maybe these effects are far to small to be noticed on this part?
My thoughts too; distortion caused by clamping on the web.
Jesus Keith, Doc was brutal mate. Just look at that bruise under your arm where they did you elbow.
Glad to hear your on the mend mate.
Hi Keith how about using the squareness comparator to check square that Steve Barton made?
Why? No need with Steve's work.
@@paulcopeland9035 I phrased that poorly. I was suggesting that Keith put the square directly on the surface plate and use the squareness comparator to check the accuracy of the newly ground square without the fixtureing that could be introducing some error.
Where did you get that hold down kit? Looks really nice. I've been looking for a nice smaller hold down kit and haven't seen anything complete.
I'm guessing he made most of it. The toe clamps aren't hard to make and "T" nuts aren't hard either. For the rest it's just hardware store nuts and bolts. I've made most of that stuff for myself although I don't have the cool box he's got you can get them from Canadian Tire, (in Canada), and I suspect Harbour Freight in the US.
Boys with their toys. Is there anything you can't do in your shop?
Joe Pi made a set of these as well as a mini fixture plate....I copied his design and made the same set, use them all the time. If you want a Fusion360 design/print, send me a PM and I'll shoot you a copy.
@@ericsandberg3167 I'm definitely interested. I'm not sure how to send a PM on here.
Balancing isnt worth the time IMO... I run grinders for a living we buy pre balanced wheels from norton and they are plenty close enough no one at my work balances wheels I'm still able to get sub 8ra finishes easily. Also I think your surface finish issue with that SG wheel was dress speed... if you watch the video you dressed extremely fast with the sg wheel using hydraulics and a lot slower with the SC (silicone carbide) wheel... any of those wheels will give a good finish it's just more of how well it cuts and how much stock removal you can get done in between dress cycles... just my 2 cents...
Have you seen OX Tools take on the squares?
Keith working on iron that can't be weighed in the tons? Will wonders never cease? ;-) Get better soon, Keith.
Just a hobbyist, but will not the surface grinder wheel change diameter when grinding , thus not keeping the distance to the workpiece exactly the same, or does these machines compensate/ indexing somehow for this change in diameter / distance to the workpiece while grinding. Just curious.
Love the trade, love your videos! But 26acremaker, i will never never ever ever pay more for a stone than my starrett micrometers!
So... if you need a square-ground fixture to grind the square, and known-squares to inspect the squareness, how was the "primordial" known-square made and verified in the first place?
Those two squares, placed face to face upright on that perfectly flat granite stone should have no space between them top to bottom.
The whiteworth 3 plate method can also be extended to squares.
you simply step grind it dead nuts. that is how tooling is made square from scratch. not by purchasing an item assumed to be square. his method to check the squareness after--------------------was simply wrong as his tenth indicator showed.
@@mzb8134 Thanks that was an interesting read! But my question was about the perpendicularity not the flatness. Found a book that explained how to reach the squareness from the withworth 3 plates: it's using a box with 2 opposing sides, flat and parallel, then the perpendicular side is made flat, and checked with an indicator and bumper with itself by reversing the box. (After setting the indicator to 0 on one side then flipping the box the indicator will show the double of the error in perpendicularity of the face)
@@jamesogorman3287 Yeah, but... they will also have no space between them if they're both tilted at the same (opposite) angles.
Keep well.....and do all the physio.
Umm, stupid question: What are they used for?
What is the difference between those stones and the ones you can sharpen a knife with?
Same base material, However these are then ground the same way as he is grinding that square so the the mating surfaces are as close to dead flat as they can be. Unlike the out of the box versions that are sort of flat.
So, one thing I've never quite understood about surface grinders: The wheel gets smaller every time it's dressed and used. How does the machine adjust for that?
This has always been my question as well. Glad I'm not alone on it.
manual machine U have to adjust the height after dressing urself
The stone is always referenced to the work by light contact establishing a relative zero point. Then you remove the amount of material by lowering the stone from that zero point. You measure the workpiece directly, more than once as you remove material, and as you grind it the reference surface becomes more uniform and accurate. Lastly you work towards the final grind with a freshly dressed stone and light cuts after once again measuring the height and zeroing it on the surface you are grinding.
@@Bakafish ah, okay, so if I touch off, then let the head come down 5 thou, and let it run over the piece until it stops cutting, then I can reasonably assume I've taken 5 thou off the piece?
The wheel stepover sideways while grinding is a fraction of the wheel width so the wear doesn't make difference within one pass as the wear happens mainly in the leading corner of the wheel. Otherwise the wear is not an issue either, except for cnc machines where the machine needs to know the wheel size after dressing
Surface grinders are a mystery to me. I know the stones are different, they are cooled and the cut depth is small, but it just seems that the stone goes away a bit at a time and would lose accuracy. Just my insanity thinking out loud here.
I had carpal tunnel surgery in the right hand about 20 years ago. Wasn't able to take time off the job long enough and was on it again within a week. Wasted procedure (like the surgeon said) it reversed the benefits of the surgery. Been living with it since. One of the hardest things for me to do for example is to find a screwdriver at my house, I don't have many because I have to use power tools for nearly everything so hand tools are always hiding, but I get by.
The wheel has thickness. Only the leading edge is eroded, by the time some is worn away there is more waiting as the cutting edge travels across the width of the cutting face. The diamond dresser is used to resquare the cutting face, and the process starts again. You have to wear out the entire face before any potential error is introduced, but used correctly, that will never happen. So it is one of the most precision processes we have.
@@Bakafish Ok, so you dress the wheel for each job basically. That makes sense as well as the leading edge wearing and the trailing surface finishing to spec. Thanks
@@marcp1180 Yes you dress the wheel, then start grinding, you make a pass and then check the stone, if you managed to run across the entire face, you redress the wheel. However that rarely happens because you don't normally remove a lot of material during this process. The idea is to machine it to within a thou or less over and then grind it to final size if at all possible.
@@Blazer02LS Thank you, I'm a small time hobby machinist and grinding wasn't any part of my learning experience. Thanks to y'all for your knowledge and for Keith bringing on a good video about it where I'd get the chance to ask.
@Sunlight through a window I think it was Project Farm that shortly ago did a comparison video of a few different brands of screwdrivers. The Harbor Freight screwdrivers quite shockingly did very well against many of the other expensive brands. You may just be doing people a favor by loaning Harbor Freight screwdrivers out.
Can you retro-fit the old grinder w/ DRO?
Do you have to balance the wheel …so it don’t have wobble in it…
Hey Keith. Would it not work when measuring the surface to turn it 180° and it should be out by the same amount in the other direction if these parallels are not exactly parallel. It's how you check a carpenter's level turn it 180° on the surface and if it's out by the same amount the other direction then the bubble is on. Actually the way you did it is correct I believe. If it's out by the same amount on the same end on both services then they should be 90° to one another
Hey Keith!
I'm interested in your precision grinding blocks, do you true them up?
I am always flattening sharpening stones, but I think you would need at least three surfaces to guarantee flatness.
my concern is that the precision grinding blocks may well be out if true of you only reference them against eachother.
I know it wouldn't matter for your end result here, cool that you have a special set of abrasives for this sort of thing. My stones for knives wouldnt cut it.
where's your table squeegy?
Classic case of machinist elbow
If the surplus came from ATL, most likely came out of the Lockheed Marietta plant
I don't envy you for getting carpel-tunnel surgery, personally I was lucky enough to avoid it. I had it years ago. I was crawling under my house in the crawl space, working on a frozen drain. I moved a hot water pipe out my way, and didn't know there was a crack in a 220V wire. I got the jolt of my life, ended up with an electrical personality, but poof! carpel-tunnel gone and haven't had a problem since.
If the "precision block" is square, flat, and parallel to 50 millionths, why isn't the square you ground square to within 50 millionths? Where did the error come in ?
Probably the machine... I'm sure theres a slight flatness error on that old girl
I think you could have gotten a more accurate, or at least more easily readable, 6" measurement by using a tenths indicator on a stand (like you used on the surface plate) and a 6" gage block as a setup piece to zero the indicator. Any difference off zero would have been a difference off 6" height.
There IS a reason to balance wheels unless you do not care about the final finish. Even more so with a cylindrical grinder.
Put new wheels on the 12” and when they ware down clean them up and put them on the 10”.
Grind two birds with one wheel……
"Nice and stoned!"
I´m not shure that i am Nice, but i am stoned! 😋
Beat me to it
Sir, unless you get super lucky, you'll probably be making hubs for your surface grinder, looked in usual places, and used different key words, nothing, notta, not 1 that even remotely looked close, but would make a great video, hope you get feeling better after surgery!!!
Keith I'm just asking a question Sir. By stoning the surface like you did to remove the Burs, 'wouldn't that in it's self change the Squareness / Flatness of the Plane of the Square? Also, by Clamping the Square like you have shown getting ready for Grinding Surface for Squareness to a Flat Plane also take it out of Flat and Square after releasing from clamps? Wouldn't it have been better to use a Electro Magnetic Lock Down to hold Part while Grinding? What about Room Temperature? Temp would also change how Flat a Surface is, does it not? How do you control this? Thank you Sir for sharing your vast knowledge with me. It is Appreciated.
These were soft cast iron squares and as such probably intended for utility work , I imagine if he was doing hardened steel precision inspection squares the technique would be different. That said, for DIY cast iron squares I would want to hand scrape them “Its the not the Destination, It's the journey.” one can buy a finished import square for less than the raw casting.
Also a precision ground stone is to a "stone" as a concrete mason's steel trowel is the the dozer that prepared the site. As the grains of the ground stone have had their points ground off there is no clearance angle and they really don't cut a flat surface to any appreciable degree, only burs that stick up can get sheared off or burnished down
@@jaytalbot1146 Well thanks for your explanation. I do really Appreciate it, but I was really wanting Keith to explain because he was the Man doing the Job.
@@kennedy67951 ....You would be waiting a long time. Keith says he reads the comments, but I don't remember if he has ever answered or commented. He has a full time job and (like a lot of us) time is limited.
The concept behind precision ground stones is that (1) all the abrasive grains have been flattened on their tops, so essentially what you end up with is a precision flat surface with crevices in it, and (2) burrs sort of get caught in the crevices and removed with a high concentration of pressure on a very small area, and (3) once they're gone, you have a flat stone surface against a flat stock surface, and the pressure is spread out over a large area, no longer sufficient to do any cutting. So it's a simple convenient way to remove the dings without cutting into the base surface.
As far as "oops," I think the major one is that when he originally set up the machine, I don't think he ever confirmed that the ways were straight, and I don't remember him saying that he ground in the top of the magnetic chuck to make sure it was parallel to the motion of the ways. In other words, he could be cutting a right angle that's tilted by the chuck surface, and depending on how he orients when he flips the fixture 90 degrees, possibly twice the chuck surface's error angle in the long direction. Maybe he did mention it and I've forgotten; I forget everything! I love Keith, and I'd bring anything to him if I needed it done quickly and "good enough", but he doesn't ever seem to have the time to dig down into the minutiae that really brings precision. I suspect it's a combination of a ToDo list that's a mile long, and then that makes it hard to have time to learn more about precision practices. I think he could do it... in a different world! :). Priorities, son -- priorities. :)
@@ydonl well, that's a better answer than I've gotten so far. Your opinion is acceptable and Appreciated.
16:26 That looks like your table speed is too high, the stone is moving too fast over the work and "burning" the finish.
you have it exactly backwards.