Checking in for 2022. I just picked up a cheap 612 grinder for work (and learning) and thought there might be some good tidbits in here. You didn't disappoint!
An additional thought on flood coolant that some may want to consider is using a refractometer to mix and maintain coolant. I was amazed at the improvement in performance of the coolant, and the life and easier clean up, when I started using a refractometer. Depending on shop conditions, sometimes I find myself adjusting my coolant strength several times a week. Thanks for all the videos, I greatly enjoy them. Marc
+v8packard That's interesting, I use a refractometer to determine when to harvest crops. In horticulture the gauge is Degrees Brix, or sugar content...1 degree Brix is 1 gram of sucrose in 100 grams of solution, etc., etc.. What are you measuring in your coolant, and what would make you change ratios? I'm certain I can look it up, but you explanation would likely make more sense if you've got the time. Thanks...Chuck.
+Knolltop Farms I use synthetic water soluble coolants and have two refractometers that measure the refractive index of each as stated in their mixing directions. One is a simple analog that reads in Brix. It seems pretty accurate. It was given to me by a rep for the coolant I use most (Rustlick). I mostly grind steel and iron automotive parts like crankshafts and flywheels, and the coolant mix I use most is 25 parts water to 1 part Rustlick, or 4%. This works out to 1.5 Brix on the scale with this coolant. A year or so ago I bought a Misco digital. It stores all the numbers I need (refractive index) for my coolant mixes. Both are very consistent with each other, but the digital is much faster. I have found that if I stray from 1.4 - 1.5 Brix I get all kinds of nuisances, from a syrup-like residue on everything when the strength is too high to wheel loading, slower cut times, and more frequent dressing when the strength is too low. I have also noticed that I never have any odor from the coolant when I keep it in this range. The one grinder has a somewhat small coolant tank, and the amount of coolant lost to evaporation and use is surprising. Basically I have gotten in the habit of checking the coolant every time I use the machine, and making adjustments as needed. This can be a pretty complex subject, and I have only a minimal amount of knowledge here, but I have found this works best for my needs. Most of what I know about using a refractometer came from a 1-on-1 session with a rep from the company where I buy the coolant. Does any of this make sense?
Absolutely perfect sense, and thanks so much for taking the time to explain, that is very considerate of you. I love science and also nature, so when I can bring one in to help the other it is very rewarding. I am glad to hear you have your mix dialed in and working, but I am sorry that you've got to add another step to setting up your machines. I guess if it makes changes less frequent and your work better in the long run, it must be more than worth it. I was amazed at how sensitive the analog one I use is, and also how much difference it makes in the quality of my various fruits and veggies to know when they've reached peak sugar content. We're about quality over quantity, and just talking about it makes me hope so much for this season's rains to bring an end to our drought and I can get back to growing food for our community :) Thanks again...Aloha, Chuck
I am really liking this new trend (at least new to me) to analysis or Q&A videos. It lets the original video flow better without too many asides or stops for explanation, and it lets you judge which parts need the most explanation (from the comments and questions asked). Different YT creators are approaching this in slightly different styles, but I've noticed that several of you are beginning to do this regularly. I vote YES on continuing this trend.
+Peter W. Meek Hi Peter, Thanks for the feedback. It sure is easier to talk than to type the same answer thirty five times. Thanks for the comment. Cheers, Tom
Very interesting and well done session. One of my greatest regrets is that I never got a chance to do any grinding. Watching you, Stan, and others makes me contemplate trying to find a machine! Thanks!
Tom, thank you for this tutorial, mechanic-ed for years and always wondered about this very subject and many more. You and your cohorts have given me the opportunity to advance and learn through osmosis! Great job of splain dat macheen.
Excellent grinder discussion. You explained so well that it soaked in painlessly. I have at times given some thought to looking for a grinder but I have no place to put one if I had it so I will leave grinding to you. Thanks for sharing.
Great info, thanks...question for PT2, do you ever relieve the grinding wheel? ie...1/2" wide wheel and put a step in the wheel of .005 for about 1/2 of the wheel face?
+outsidescrewball With the right dresser you can put different profiles on the wheel to grind into the work, or avoid grinding certain areas in a part. A step as you describe is quite easy, you can go deeper into the wheel and wider as well.
+outsidescrewball Hi Chuck, I would do something like that grinding up to a shoulder with a grinding relief. Something like a vee block or an inside of an angle plate. Thanks for the comment. Cheers, Tom
Good video, good explanation. years ago, I asked some of those questions, about wheel wear. My wise old mentor told me, "if you're only grinding off a enth, you can only have a tenth of inaccuracy. How simple, & how true. Thanks for these videos......................Dick
The guy who does grinding for me, he considers the magnetic chuck a consumable, yes, even he admits it's an expensive consumable(here in EU i could never justify replacing one so quickly), but, in the search for perfection, you have to throw something under the wheels otherwise you're too damn busy taking care of that and not enough time is spent on the part itself(his approximate words). Liked the video, as always, a treasure trove of things that i'd never learn otherwise lest i'd quit my day job and become a full time machinist. Invaluable, really.
A bit of info on why you get sparks: The heat per gram of material removed isn't really that much different than a heavy milling cut, but the mass of the chip is a lot less. On the mill, the chips burn a little on the surface, but the chip absorbs the heat produced during the burn sufficiently to allow the surface to cool, and you get a hot chip. On the grinder, the chips are so small that they can't absorb the heat produced during oxidation faster than it is produced, so the chips get hotter. This is why, in some cases, the chips get brighter and hotter away from the wheel.
You eluded to it, but not sure you finished the thought on the relationship between stepover and the amount of infeed. Going from memory, I believe you were stepping .010" while taking a .003" cut? What do you typically step when taking .0005"? Thanks for the great video!
Hey Tom, Love the info . Great information, I used to think the surface grinder was a terribly boring tool. Having watched you guys use it. I love it for what it gives you in the final product. Keep the videos coming. jerry
Tom I have a Question ...Could you put a rubber abrasive wheel on the machine .Something like a Cratex Brand and use it to super polish a meatal surface ?
+not2fast4u2c You can just touch up ground parts on some wet or dry sandpaper. A good surface ground finish is almost polished anyways. But sometimes we'd buff parts a little on sandpaper on a surface plate. Maybe 400 grit? You have to rub a whole lot to actually change the dimension. A few swipes isn't going to matter. Although I kind of like a really nice surface ground finish myself. To get a really good finish you have to use a fresh dressed wheel. Dull wheels streak. How you dress the wheel even matters. You don't want to thread it.
Hi Tom,Great video, very informative. I was wondering if you've ever used the air cooling nozzle with cutters on the mill? Will it keep an endmill cool? Thanks
+Chance Peutert Hi Chance, Yes I have. Sometimes you are not allowed to use coolant because of contamination issues. Ceramics is a good example. The one I have would be good for smallish end mills not big hogging cutters. Thanks for the comment. Cheers, Tom
Tom, Thank You for this video I love grinding except for the dust of course and like your clean nice grinder. I did have a couple of questions. First is how to lap my stones I have one like yours and other smaller ones? Also is there a type of stone which can be used on aluminum which can be easily cleaned? We never allow people grinding alum on grinding wheels because as you know that is a huge and dangerous sin. I notice also you have the safety cover on which is great yet in our shop it is removed 95% of the time. We also use diamond wheels for relieving end mills and have been told to use the method you described of coming down going back up moving over and doing the other cuts to the same dial number to in theory protect the wheel from people using it like a lathe going back and forth. Usually shops which have them get very mad when they are abused and destroyed and so the people who use the diamond wheel are approved to do so. So we do all relief for most of the guys who never can get it. Thank You Mr. Lipton.
+Lew Sou Hi Lew, I lap my stones on a diamond lap. If you have two stones you can also lap them together. The diamond works great and you can get them really flat and smooth. Thanks for the comment. Cheers, Tom
Just got my first surface grinder! An old, 50-60's i believe, doall G7 hydraulic feed. Whattya know everything works. So excited but cant use it yet because I need to get a couple vfd's. Any suggestions for must haves for the grinder? I already have a koolmist setup mounted and an old Brown and Sharpe perm mag chuck. Probably going to get a new chuck since all my work is thin and small parts (knife blades) and this B&S has poles spaced WAY out. Gotta wait on that though as the Suburban chuck is twice what I paid for the grinder itself
+Finn Custom Knives Hello Mr Finn, you can probably find many "fine pole" magnetic chucks ( Walker, B & S, etc. ) on flea bay or used machine dealers, if you are lucky enough to have one local to you. Where are you located, btw ? I can recommend "Cook's Machine Tools " as a good, fair dealer located in south central NJ and also an honest e-bay seller. They have many surface grinders and accessories available. Good luck !
So which is better for round parts? I have only ever done conventional on rounds but I will admit to having the occasional "powered" round if I got too greedy. lol
Hey Brian, The only "climb " grinding, in cylindrical work, that I can think of is centerless grinding. And the part rotates with the wheel because the wheel is what causes the part to turn. I can't think of any benefit for climb grinding in any other type of cylindrical grinding. Congrats on getting your steel tied together, or at least starting to. I, of course, don't know what you've done since your last video.
Jerry Long Thanks for the insight. all I have done since that video is more beam prep. I hope to be able to get the other beam up and test fit the crane and hoist this weekend maybe since I will have 2 full days to work on it what with New Years off. Happy New Years to you and of course Tom if he reads this before then.
oxtoolco The school of hard knocks can be a brutal teacher. Throwing parts from the grinder can be even more interesting than the powered rounds. Took me not long to realize magnet chucks don't hold like clamps or a lathe chuck and require a fine touch.
Tom, Thanks for a nice presentation in answering questions about grinding a subject about which I know very little. I noticed as I was watching the video that in the background there are files stored on what appears to be a magnetic strip. Does the magnetism cause a problem when the files are being used on ferrous materials?
+Gordon Eckler Hi Gordon, Yes sometimes it does. Its funny I don't use those particular one very much. They are mainly there to make me appear to be organized. Thanks for the comment. Cheers, Tom
+dans-hobbies Hi Dan, I don't think its Axe specific. Its a two sided Norton Crystolon stone. Fine on one side (red) coarse on the other. Thanks for the comment. Cheers, Tom
Great info Tom, I'm looking to purchase a grinder for my shop, could you give some key pointers on what to look for in a machine? I'm looking at a small to medium size machine for Gunsmithing. I really enjoy you and Stan's grinding videos. Thanks
+Marc Tennill Hi Marc, Lots of grinders out there. Smooth spindle is top of the list. 6x12 and 6x18 are common smaller machines good for toolroom work. $600 to $1500 will get you a really nice machine. Thanks for the comment. Cheers, Tom
+johnptc Hey John, Lots of factors in surface finishes. As a matter of fact I am planning a series on that very subject. I cut and machined a bunch of A2 tool steel blanks that I'm going to share around to folks that want to contribute their techniques. Out for heat treating now. There is a data sheet to fill out with the grinding parameters used. The pieces are small enough to mail around so we can evaluate them in one place and evaluate techniques and tools. Sounds like fun right? Best, Tom
I know this is an old video, but if you see this would you consider showing us a clip of a Infrared (flir) camera showing the heat signatures while using the air nozzle? -thanks for sharing with us!
I really enjoy your video's and I get a Laugh how many times you say. (and um)(and a) Have you ever notice that while editing your video's. Just having some fun man. Happy New Year to you and the family.
Ruben I've heard Tom say that he was going to um, and ah his way through some things. So he knows he does it. He just wants to use the right words. But they don't always roll off the tongue discussing technical topics.
+Paul Frederick My videos seem to be plagued by long pauses while I look for the right word. (Or they may just be "senior moments".) It's something I really need to work on. I might even need to write something like a script so I can think things out beforehand. It would be tough with my style of machining, as I tend to plan on the fly. Maybe I could get really aggressive on my editing and clip all those pauses out. It might make for some really short videos. ;-)
Peter W. Meek color commentating in the moment is tough to do. You could do some voice over narration in your editing if you like. I am watching your, "Toolholder Dovetails" video now. If you could do some work closeups like Tom does in his videos. I think that might spice your content up some. There was also a spot in the beginning where I thought a still image inset might have been nice too, if you had pictures of that swap meet that you went to. Changing things up can help pacing out.
Great video, Tom. A question, if I may. In regards to the two mating surfaces (i.e. sliding surfaces), the softer one will give, wear and degrade over time. To me it seems that the ideal situation (in order to maintain accuracy) would be for the two surfaces to have the same hardness, but you suggest otherwise. May I have a theoretical explanation as to why? Thanks! :)
+aryesegal1988 Hi Aryesegal, It depends on something called the pressure velocity relationship. Each material has a threshold where it will wear and perform predictably. Bronze bearings are a good example. When you have two like materials say steel on steel of the same composition the failure mode is material welding at a microscopic level. Dirt and lubricants also play a major role. I should have expanded a bit and mentioned two like materials that are very hard like say gage blocks can perform quite nicely together. Hard to answer in a few comment lines. Check out PV ratings for different materials. Thanks for the comment. Cheers, Tom
Tom what wheel are you running there? It's clearly not a white aluminium oxide wheel and looks to be something much harder. How many CFM does that air chiller use? I seem to recall you were only going to use a very small compressor when you put one in. I too grind "deep" with small step over. It seems there is an increasing number of people grinding this way, and I get much better results on my grinder. For others, apart from the traverse speed and other factors Tom mentioned, the grit and hardness of the bond of the wheel is probably one of the biggest variables you can control. You typically want to run as soft a wheel as you can get away with (at least for non-production work), as the breakdown of the wheel exposes fresh cutting surfaces and will grind cooler with a better finish. On the other hand if you dress the wheel with a profile, that too will break down quickly, so it's a juggle. It will also depend on the material being ground. I describe the wear on wheels to those who ask as forming a ramp on the leading edge. As the wheel wears more, the ramp gets wider. The following parts of the wheel past that ramp really aren't doing anything, but will glaze over lose sharpness and that rubbing action will add heat to the work. It also leaves a poor finish. Once that "ramp" reaches about 1/3 of the way across the wheel I will re-dress the wheel. I almost always grind back to front ie towards me. The reason being that I can see the grind more easily. The other reason is that preserves the back edge, so the final pass will be front to back on a fresh edge. To others considering buying a similar small grinder I would suggest to go for it. It can be one of the most useful things in a shop, after a linisher, lathe, and mill. With a few accessories it can be made to function in other roles too and maybe Tom will cover that in subsequent videos.
+Pete F Hi Pete, The wheel you see in this video is not the same one we were using to grind the vise. This is a Norton 5SG 46Grit K hardness. I use this one for softer steel. The vise job was a AO 46H hardness salt and pepper wheel. The chiller is fairly low volume roughly 6CFM consumption. It specially designed to be quiet which accounts for its $$$ and low air consumption. Thanks for the comment. Cheers, Tom
Actually one of the best ones on SG...yet it was nowhere near the top in searches. Should have just come straight to Ox :) Currently grinding a 40" x 10" surface on my 20" x 6" grinder. Yeh, it's not that fun. Ha! Deflection, deflection, deflection. Doing ok for a noob, though. Currently got 0.0005" error across the 40". I can live with 1/2 a thou. All thanks to learning from greats like Tom :D
The only time I can think of where its ok to have two surfaces of the same hardness rubbing together is to make the two surfaces mate together perfectly.
+Earl Selinger Hi Earl, What I should have added it if the two surfaces are both very hard. Any two soft surfaces will degrade with the tiniest speck of dirt. In a clean environment you may be right.Thanks for the comment. Cheers, Tom
Checking in for 2022. I just picked up a cheap 612 grinder for work (and learning) and thought there might be some good tidbits in here. You didn't disappoint!
Very good video Tom. I grind almost every day and have for 28 years. Your info is spot on . I learn something new on the grinder every time I use one.
+Ken s (Toolmaker476) Hi Ken,
Thanks for the nice comment. Mostly I learn what not to do on a grinder on a daily basis......
Cheers,
Tom
An additional thought on flood coolant that some may want to consider is using a refractometer to mix and maintain coolant. I was amazed at the improvement in performance of the coolant, and the life and easier clean up, when I started using a refractometer. Depending on shop conditions, sometimes I find myself adjusting my coolant strength several times a week.
Thanks for all the videos, I greatly enjoy them.
Marc
+v8packard That's interesting, I use a refractometer to determine when to harvest crops. In horticulture the gauge is Degrees Brix, or sugar content...1 degree Brix is 1 gram of sucrose in 100 grams of solution, etc., etc..
What are you measuring in your coolant, and what would make you change ratios? I'm certain I can look it up, but you explanation would likely make more sense if you've got the time. Thanks...Chuck.
+Knolltop Farms I use synthetic water soluble coolants and have two refractometers that measure the refractive index of each as stated in their mixing directions. One is a simple analog that reads in Brix. It seems pretty accurate. It was given to me by a rep for the coolant I use most (Rustlick). I mostly grind steel and iron automotive parts like crankshafts and flywheels, and the coolant mix I use most is 25 parts water to 1 part Rustlick, or 4%. This works out to 1.5 Brix on the scale with this coolant. A year or so ago I bought a Misco digital. It stores all the numbers I need (refractive index) for my coolant mixes. Both are very consistent with each other, but the digital is much faster.
I have found that if I stray from 1.4 - 1.5 Brix I get all kinds of nuisances, from a syrup-like residue on everything when the strength is too high to wheel loading, slower cut times, and more frequent dressing when the strength is too low. I have also noticed that I never have any odor from the coolant when I keep it in this range. The one grinder has a somewhat small coolant tank, and the amount of coolant lost to evaporation and use is surprising. Basically I have gotten in the habit of checking the coolant every time I use the machine, and making adjustments as needed.
This can be a pretty complex subject, and I have only a minimal amount of knowledge here, but I have found this works best for my needs. Most of what I know about using a refractometer came from a 1-on-1 session with a rep from the company where I buy the coolant.
Does any of this make sense?
Absolutely perfect sense, and thanks so much for taking the time to explain, that is very considerate of you. I love science and also nature, so when I can bring one in to help the other it is very rewarding.
I am glad to hear you have your mix dialed in and working, but I am sorry that you've got to add another step to setting up your machines. I guess if it makes changes less frequent and your work better in the long run, it must be more than worth it.
I was amazed at how sensitive the analog one I use is, and also how much difference it makes in the quality of my various fruits and veggies to know when they've reached peak sugar content.
We're about quality over quantity, and just talking about it makes me hope so much for this season's rains to bring an end to our drought and I can get back to growing food for our community :)
Thanks again...Aloha, Chuck
Learned several new things today. Although this I an older video it’s timeless for learning and I am. I’ll watch multiple times. Thank you.
I am really liking this new trend (at least new to me) to analysis or Q&A videos. It lets the original video flow better without too many asides or stops for explanation, and it lets you judge which parts need the most explanation (from the comments and questions asked). Different YT creators are approaching this in slightly different styles, but I've noticed that several of you are beginning to do this regularly.
I vote YES on continuing this trend.
+Peter W. Meek Hi Peter,
Thanks for the feedback. It sure is easier to talk than to type the same answer thirty five times. Thanks for the comment.
Cheers,
Tom
Very interesting and well done session. One of my greatest regrets is that I never got a chance to do any grinding. Watching you, Stan, and others makes me contemplate trying to find a machine! Thanks!
Tom, thank you for this tutorial, mechanic-ed for years and always wondered about this very subject and many more. You and your cohorts have given me the opportunity to advance and learn through osmosis! Great job of splain dat macheen.
Excellent grinder discussion. You explained so well that it soaked in painlessly. I have at times given some thought to looking for a grinder but I have no place to put one if I had it so I will leave grinding to you. Thanks for sharing.
Great info, thanks...question for PT2, do you ever relieve the grinding wheel? ie...1/2" wide wheel and put a step in the wheel of .005 for about 1/2 of the wheel face?
+outsidescrewball With the right dresser you can put different profiles on the wheel to grind into the work, or avoid grinding certain areas in a part. A step as you describe is quite easy, you can go deeper into the wheel and wider as well.
+outsidescrewball Hi Chuck,
I would do something like that grinding up to a shoulder with a grinding relief. Something like a vee block or an inside of an angle plate. Thanks for the comment.
Cheers,
Tom
Excellent grinding tips and explanations. I especially liked that paper trick.
Good video, good explanation. years ago, I asked some of those questions, about wheel wear. My wise old mentor told me, "if you're only grinding off a enth, you can only have a tenth of inaccuracy. How simple, & how true. Thanks for these videos......................Dick
The guy who does grinding for me, he considers the magnetic chuck a consumable, yes, even he admits it's an expensive consumable(here in EU i could never justify replacing one so quickly), but, in the search for perfection, you have to throw something under the wheels otherwise you're too damn busy taking care of that and not enough time is spent on the part itself(his approximate words).
Liked the video, as always, a treasure trove of things that i'd never learn otherwise lest i'd quit my day job and become a full time machinist. Invaluable, really.
Let's renew this video. It's full of good information.
I have a very clean Brown and Sharpe 618 Micromaster. I'm learning Tom.
Thanks.
A bit of info on why you get sparks: The heat per gram of material removed isn't really that much different than a heavy milling cut, but the mass of the chip is a lot less. On the mill, the chips burn a little on the surface, but the chip absorbs the heat produced during the burn sufficiently to allow the surface to cool, and you get a hot chip. On the grinder, the chips are so small that they can't absorb the heat produced during oxidation faster than it is produced, so the chips get hotter. This is why, in some cases, the chips get brighter and hotter away from the wheel.
+john john Hi John,
Well said. Proportionally they are very similar cutting actions. Thanks for the comment.
Cheers,
Tom
You eluded to it, but not sure you finished the thought on the relationship between stepover and the amount of infeed. Going from memory, I believe you were stepping .010" while taking a .003" cut? What do you typically step when taking .0005"? Thanks for the great video!
What a great video, full of information, guidance and advice. Thanks. By the way what great comments and discussion it has stimulated below!
You should do a surface grinding training series.
+Clarence Wollman
AGREED!
Thatlazymachinist has a very good grinding tutorial series, check it out. He also contributed to the WIYB by making tap blocks. Daniel
Hey Tom,
Love the info . Great information, I used to think the surface grinder was a terribly boring tool. Having watched you guys use it. I love it for what it gives you in the final product.
Keep the videos coming.
jerry
good video I have never done grinding like this so its good to learn
Tom I have a Question ...Could you put a rubber abrasive wheel on the machine .Something like a Cratex Brand and use it to super polish a meatal surface ?
+not2fast4u2c You can just touch up ground parts on some wet or dry sandpaper. A good surface ground finish is almost polished anyways. But sometimes we'd buff parts a little on sandpaper on a surface plate. Maybe 400 grit? You have to rub a whole lot to actually change the dimension. A few swipes isn't going to matter. Although I kind of like a really nice surface ground finish myself. To get a really good finish you have to use a fresh dressed wheel. Dull wheels streak. How you dress the wheel even matters. You don't want to thread it.
Is this air gun on 12:53 a "venturi" or a "vortex tube" style.
+mikrobe1 Hi Mike,
I'm pretty sure its a venturi type. Its made by Silvent in Sweden. Thanks for the comment.
Cheers,
Tom
Really love the equipment user manual vids. Thx for vid.
Great explanations Tom, very informative, thanks for sharing
Hi Tom,Great video, very informative. I was wondering if you've ever used the air cooling nozzle with cutters on the mill? Will it keep an endmill cool? Thanks
+Chance Peutert Hi Chance,
Yes I have. Sometimes you are not allowed to use coolant because of contamination issues. Ceramics is a good example. The one I have would be good for smallish end mills not big hogging cutters. Thanks for the comment.
Cheers,
Tom
Tom, Thank You for this video I love grinding except for the dust of course and like your clean nice grinder. I did have a couple of questions. First is how to lap my stones I have one like yours and other smaller ones? Also is there a type of stone which can be used on aluminum which can be easily cleaned? We never allow people grinding alum on grinding wheels because as you know that is a huge and dangerous sin. I notice also you have the safety cover on which is great yet in our shop it is removed 95% of the time. We also use diamond wheels for relieving end mills and have been told to use the method you described of coming down going back up moving over and doing the other cuts to the same dial number to in theory protect the wheel from people using it like a lathe going back and forth. Usually shops which have them get very mad when they are abused and destroyed and so the people who use the diamond wheel are approved to do so. So we do all relief for most of the guys who never can get it. Thank You Mr. Lipton.
+Lew Sou Hi Lew,
I lap my stones on a diamond lap. If you have two stones you can also lap them together. The diamond works great and you can get them really flat and smooth. Thanks for the comment.
Cheers,
Tom
Just got my first surface grinder! An old, 50-60's i believe, doall G7 hydraulic feed. Whattya know everything works. So excited but cant use it yet because I need to get a couple vfd's.
Any suggestions for must haves for the grinder?
I already have a koolmist setup mounted and an old Brown and Sharpe perm mag chuck. Probably going to get a new chuck since all my work is thin and small parts (knife blades) and this B&S has poles spaced WAY out. Gotta wait on that though as the Suburban chuck is twice what I paid for the grinder itself
+Finn Custom Knives Hello Mr Finn, you can probably find many "fine pole" magnetic chucks ( Walker, B & S, etc. ) on flea bay or used machine dealers, if you are lucky enough to have one local to you. Where are you located, btw ? I can recommend "Cook's Machine Tools " as a good, fair dealer located in south central NJ and also an honest e-bay seller. They have many surface grinders and accessories available. Good luck !
Thanks Tom. Great explanation as usual.
Happy New Year
John
So which is better for round parts? I have only ever done conventional on rounds but I will admit to having the occasional "powered" round if I got too greedy. lol
Hey Brian,
The only "climb " grinding, in cylindrical work, that I can think of is centerless grinding. And the part rotates with the wheel because the wheel is what causes the part to turn.
I can't think of any benefit for climb grinding in any other type of cylindrical grinding.
Congrats on getting your steel tied together, or at least starting to. I, of course, don't know what you've done since your last video.
Jerry Long
Thanks for the insight. all I have done since that video is more beam prep. I hope to be able to get the other beam up and test fit the crane and hoist this weekend maybe since I will have 2 full days to work on it what with New Years off. Happy New Years to you and of course Tom if he reads this before then.
+bcbloc02 Happy New Year, and looking forward to seeing you move into your new shop this year.
+bcbloc02 Powered round not good. Sounds like you figured it out at Hard Knocks U. Thanks for the comment.
Cheers,
Tom
oxtoolco
The school of hard knocks can be a brutal teacher. Throwing parts from the grinder can be even more interesting than the powered rounds. Took me not long to realize magnet chucks don't hold like clamps or a lathe chuck and require a fine touch.
I was wondering how much of the wheel is actually cutting, thanks for clearing that up.
So when are you going back and finish up the Wilton Baby Bullet?
Tom,
Thanks for a nice presentation in answering questions about grinding a subject about which I know very little. I noticed as I was watching the video that in the background there are files stored on what appears to be a magnetic strip. Does the magnetism cause a problem when the files are being used on ferrous materials?
+Gordon Eckler Hi Gordon,
Yes sometimes it does. Its funny I don't use those particular one very much. They are mainly there to make me appear to be organized. Thanks for the comment.
Cheers,
Tom
Great video as always, thanks for spending your time to make and post. I always learn something useful watching your videos.
Randy
Great topic, Tom. Must take some serious patience to do grinding on a daily basis.
Hey Tom,
Is the stone you use to remove nicks an axe sharpening stone?
+dans-hobbies Hi Dan,
I don't think its Axe specific. Its a two sided Norton Crystolon stone. Fine on one side (red) coarse on the other. Thanks for the comment.
Cheers,
Tom
Great info Tom, I'm looking to purchase a grinder for my shop, could you give some key pointers on what to look for in a machine? I'm looking at a small to medium size machine for Gunsmithing. I really enjoy you and Stan's grinding videos. Thanks
+Marc Tennill Hi Marc,
Lots of grinders out there. Smooth spindle is top of the list. 6x12 and 6x18 are common smaller machines good for toolroom work. $600 to $1500 will get you a really nice machine. Thanks for the comment.
Cheers,
Tom
Thanks for the video Tom.
how do you get a 'mirror' like finish with a small surface grinder on hard steel ????
+johnptc Hey John,
Lots of factors in surface finishes. As a matter of fact I am planning a series on that very subject. I cut and machined a bunch of A2 tool steel blanks that I'm going to share around to folks that want to contribute their techniques. Out for heat treating now. There is a data sheet to fill out with the grinding parameters used. The pieces are small enough to mail around so we can evaluate them in one place and evaluate techniques and tools. Sounds like fun right?
Best,
Tom
waiting for the piece :)
hey tom, great videos keep up the good work... one question... when are you ganna finish the baby bulit vice project?
best wishes... Andy
I know this is an old video, but if you see this would you consider showing us a clip of a Infrared (flir) camera showing the heat signatures while using the air nozzle? -thanks for sharing with us!
Thanks for the answers Tom!
Are you worried about abrasive dust in the shop?
In polishing it's called "cut" and "color" similar theory to conventional vs climb, against or with the direction of wheel travel
+bendavanza Hi Ben,
I had not heard that one before. Are you talking about commercial polishing operations? Thanks for the comment.
Cheers,
Tom
I really enjoy your video's and I get a Laugh how many times you say. (and um)(and a) Have you ever notice that while editing your video's. Just having some fun man.
Happy New Year to you and the family.
+Ruben Tom has made mention of it occasionally in his videos.
+Paul Frederick I must of miss that video man. I've try many time to count but I get mix up with the um and a.
Ruben
I've heard Tom say that he was going to um, and ah his way through some things. So he knows he does it. He just wants to use the right words. But they don't always roll off the tongue discussing technical topics.
+Paul Frederick
My videos seem to be plagued by long pauses while I look for the right word. (Or they may just be "senior moments".) It's something I really need to work on. I might even need to write something like a script so I can think things out beforehand. It would be tough with my style of machining, as I tend to plan on the fly. Maybe I could get really aggressive on my editing and clip all those pauses out. It might make for some really short videos. ;-)
Peter W. Meek
color commentating in the moment is tough to do. You could do some voice over narration in your editing if you like. I am watching your, "Toolholder Dovetails" video now. If you could do some work closeups like Tom does in his videos. I think that might spice your content up some. There was also a spot in the beginning where I thought a still image inset might have been nice too, if you had pictures of that swap meet that you went to. Changing things up can help pacing out.
Great video, Tom. A question, if I may. In regards to the two mating surfaces (i.e. sliding surfaces), the softer one will give, wear and degrade over time. To me it seems that the ideal situation (in order to maintain accuracy) would be for the two surfaces to have the same hardness, but you suggest otherwise. May I have a theoretical explanation as to why? Thanks! :)
+aryesegal1988 Hi Aryesegal,
It depends on something called the pressure velocity relationship. Each material has a threshold where it will wear and perform predictably. Bronze bearings are a good example. When you have two like materials say steel on steel of the same composition the failure mode is material welding at a microscopic level. Dirt and lubricants also play a major role. I should have expanded a bit and mentioned two like materials that are very hard like say gage blocks can perform quite nicely together. Hard to answer in a few comment lines. Check out PV ratings for different materials. Thanks for the comment.
Cheers,
Tom
oxtoolco Thank you very much for the reply, Tom. Will definitely look more into it.
That was a really good video!
Excellent info. Thanks for posting!
Tom what wheel are you running there? It's clearly not a white aluminium oxide wheel and looks to be something much harder.
How many CFM does that air chiller use? I seem to recall you were only going to use a very small compressor when you put one in.
I too grind "deep" with small step over. It seems there is an increasing number of people grinding this way, and I get much better results on my grinder. For others, apart from the traverse speed and other factors Tom mentioned, the grit and hardness of the bond of the wheel is probably one of the biggest variables you can control. You typically want to run as soft a wheel as you can get away with (at least for non-production work), as the breakdown of the wheel exposes fresh cutting surfaces and will grind cooler with a better finish. On the other hand if you dress the wheel with a profile, that too will break down quickly, so it's a juggle. It will also depend on the material being ground.
I describe the wear on wheels to those who ask as forming a ramp on the leading edge. As the wheel wears more, the ramp gets wider. The following parts of the wheel past that ramp really aren't doing anything, but will glaze over lose sharpness and that rubbing action will add heat to the work. It also leaves a poor finish. Once that "ramp" reaches about 1/3 of the way across the wheel I will re-dress the wheel. I almost always grind back to front ie towards me. The reason being that I can see the grind more easily. The other reason is that preserves the back edge, so the final pass will be front to back on a fresh edge.
To others considering buying a similar small grinder I would suggest to go for it. It can be one of the most useful things in a shop, after a linisher, lathe, and mill. With a few accessories it can be made to function in other roles too and maybe Tom will cover that in subsequent videos.
+Pete F Hi Pete,
The wheel you see in this video is not the same one we were using to grind the vise. This is a Norton 5SG 46Grit K hardness. I use this one for softer steel. The vise job was a AO 46H hardness salt and pepper wheel. The chiller is fairly low volume roughly 6CFM consumption. It specially designed to be quiet which accounts for its $$$ and low air consumption. Thanks for the comment.
Cheers,
Tom
+oxtoolco Ok thanks Tom. I've heard about the chillers but never seen one run and always thought hey were air hogs. I'll look into them.
Great video! Learned a lot!
tom nice info.great video.
Actually one of the best ones on SG...yet it was nowhere near the top in searches. Should have just come straight to Ox :) Currently grinding a 40" x 10" surface on my 20" x 6" grinder. Yeh, it's not that fun. Ha! Deflection, deflection, deflection. Doing ok for a noob, though. Currently got 0.0005" error across the 40". I can live with 1/2 a thou.
All thanks to learning from greats like Tom :D
Flutes Of An End Mill was my favorite Simon & Garfunkel album
what is the smell of grinding frozen meat?
I never see you use an indicator to check yourself before grinding
The only time I can think of where its ok to have two surfaces of the same hardness rubbing together is to make the two surfaces mate together perfectly.
+Earl Selinger Hi Earl,
What I should have added it if the two surfaces are both very hard. Any two soft surfaces will degrade with the tiniest speck of dirt. In a clean environment you may be right.Thanks for the comment.
Cheers,
Tom
Thumbs up, Also I posted a shop and get to know me video . I really enjoy your videos Tom.
good stuff tom
big subject broken down nicely
I learned something! :)
+John Galt Hi John,
Thanks for the comment.
Cheers,
Tom
Why dont you grind an old anvil it will be interesting
Helpful.
And I thought it was for dust control.