I learned that from a toolmaker 30 years ago. My chuck on the lathe still good, first tighten to 2-3 microns!. The important thing is to always tighten in the same chuck key hole, so that the scroll is in the orientation, internally as when jaws were first ground. As well as grinding the jaws, I used a mild steel bar in the tailstock, grinding paste, and did final lapping finish on the jaws, tightening down on the bar and grinding paste. As long as jaw numbers are always sequenced the same, works a treat! Can get better than that, with the soft hammer, as it is tightened. 2-3 microns is perfect for most jobs in the lathe, (and I have a tool post grinder, too). Hope this helps ;)
I've watched several videos on truing a 3 jaw chuck. I saw this one with the Suburban Tool Inc. name and knew I was going to see the right way to do it.
I am learning a lot from these videos, we have never have an opportunity to work with talented and experienced people like Don, he is a real master of these kind of work
That is such a great lesson! This is why I love learning form experienced old timers! I would have never figured that one. In our shop, we always just cut jaws to fit whatever job we're running if it's critical. I can't ever recall a single time in over 8yrs working there, anyone ever doing such a method. Then again, it would be such overkill for the work we get. Very cool lesson Mr Don! Highly appreciated! 😊
Have seen similar done in another video - but they removed 1 bolt from each jaw, fitted a longer bolt in each jaw and used those to clamp a machined ring - so the jaws are all under normal tightening tension without the normal jaw faces being obscured - so the full length of the jaws can be ground.
I was all set to grind my three jaw and watching how others did it because I was convinced that is what I had to do. Then I watched this video and saw the method of truing the chuck to the back plate. No grinding needed after that I was shocked, thanks very much for that.
For all those wanting to know a setting ring is the way to ensure you machine jaws under the correct vector Look up Hass how to cut soft jaws this will help in understanding. A 3 jaw is only going to be as acurate as the scroll and guides so beware of constantly grinding hard jaws to gain accuracy at different diameters, soft jaws are available for most chucks and are a lot cheeper.
After 55 years of lathe maching. Listen to this. Even four jaw Chucks can use this method. Have a plate made which has 4 jaw and 3 jaw holes drilled into it at proper diameter.and on the outter bolt holes of your chuck. remove the allen head bolts and put a bolt in there to tighten the jaw. clamp in that ring hard what preasure you will be using for your prodject. then grind the inner face of the jaws. What you will find is perfection. Remove the ring and replace the allen head bolt. Thanks for allowing me to imput.
This is probably the most accurate and most professional way that's true but wrong or right is not the question also other ways work but not so precise if not done properly... This is a very good way to come to the goal...
Thank you for sharing that😊 These days I wire EDM a hole in a 1” thick plate to a wring or light press fit to the OD of my bushing, install it in the plate, then wire EDM the ID. Good size control and dead zero concentricity & taper. Or a specific taper if I want. Always good to know the alternative ways if you have certain equipment - yours is timeless 👍
The chuck will grip better and run truer by loading the jaws with a hollow ring with 3 pins that fit into the inner bolts that hold the jaws on. This makes the jaws spring outward like they will under gripping pressure when holding a short part that only engages the tip of the jaws. When the jaws are ground like this you can see the tip of the jaws engage the part first and then as you increase the chucking pressure you see the jaws finally engage the part at the back of the jaws. This will make a chuck perform unbelievably better especially on lathe work with a lot of part hanging out of the chuck. The difference has to be experienced to be believed!
+SuburbanTool Inc IMO other than gripping force, chucking techniques are the same for turning and grinding. A chuck will always perform better by loading at the nose of the jaws. I am not trying to be a know it all Jerk, but a lot of beginners watch these videos and I think it is important to point out nuances of technique that will help them as all of your videos do.
SuburbanTool Inc I do not have a grinder I could attach to my carriage, so one at a time I aligned my jaws with an indicator, in a vise, on my milling machine. Then in the mill's spindle, using a grinding wheel I had previously dressed true, I removed the necessary amount from the jaws. I brought the runout down from .012 to .001 Needless to say I was very happy that it worked. This is certainly not the preferred method, but it was the only one I was able to implement.
+ROBRENZ We thank you for your comment and concern however,we were size specific. That is we have a 1" dia. part and we grind at 1". If you grind the jaws at 1" and then chuck up a 2", 3" , 4" part there will be error due to the inaccuracy of the scroll.
+SuburbanTool Inc I agree completely with those comments and that is not what I am nitpicking about. My point is that loading the master jaws while grinding the jaws does not simulate the jaw forces and deflections that occur while gripping the part. That is why loading the jaws at the nose with a standard chuck jaw boring ring will give more stable gripping with less pressure. Haas has 2 excellent videos on YT on proper soft jaw turning and boring techniques that show the point better than my explanation. Thanks for not just deleting my comments and being willing to have discussion.
Greetings from Oz again--Don that was so very very good---that sort of accuracy from a 3 jaw---I would not have believed it....Keep up the vids,if you have got time to make them I sure have got time to watch them..I am going to watch this vid again..
I just found you guys 2-15-2016.. I have had a great time watching and learning from your videos! Thank you for the information, especially this video (so far, I have many many more to watch yet, lol). Every time I have ground my jaws, I would still have about [0.001"] of total run out. Due to how I would grind the I.D. clamp area, all the while having applied O.D. force on the jaws. I now know why and where this run out is coming from, it is coming from the scroll indifference's. This never once crossed my mind. Thank you!
That's the way my Dad showed me back when I was 11 years old . I'm 58 now and it still the way I do it and for lathe soft jaws as well . Old Tool Maker JT Hay Fort Worth Texas
+SuburbanTool Inc Thanks for asking. The new shop is great. I think you will appreciate this. The grinding room should be finished this month. It will house a 6x18 Harig surface grinder, KO lee universal tool and cutter grinder, plus some smaller bench grinders, and its own 2 hp dust collecting system . All the machine have been rebuilt and are painted my favorite color for machines, high gloss antique white. Don the next time you're in Atlanta you should come by. Thanks Dale d
took mine from near .02 out to .0015 by using receipt paper between the backing plate and the Chuck. put a pipe in the Chuck for leverage and only one screw needs to be loosened to get paper in a position
i think the only problem with this technique is that it depends on having a VERY VERY precise spiral cut into the jaw tensioning mechanism in the chuck ... if there's ANY deviation at all - which there likely IS - you will get different concentricity at different diameters (or?)
I really enjoyed this video. It's very clear on the process. Hunting grinding wheels or points has been a challenge. Are there catalogs you like for grinding tools? What type of abrasives do you like to use (aluminum oxide, other)?
I could watch these videos all day long! And not even get a tad bit bored..... really great stuff I am happy to see the sharing of this information because it’s tricks and tips like this that give the knowledge hungry student of this trade one more tool added to their bag”o” tricks.
Loved that grinder and technique, thanks for sharing and taking the time, energy and money to produce your content. We have to keep loading content ants sharing our skills or all the new generation of skilled craftsman will only know CNC and not have a real clue to what it takes to trouble shoot and make "parts"... Or how to be "manly" (trigger warning)...
I like the Buck chucks that have 4 screws over the ones with 3 screws. The 3 screw chucks will only dial in to about .0005 and the 4 screw chucks will dial in within .0001. You are right there are several ways to do this although using an out-lock will give better results on worn out chucks.
I thought I was the only one who enjoyed using an ID and OD grinder haha. Haven't used one in years since I was trained on one at my old trade school. Made a rotation stage on it out of hardened 17-4 PH steel. The part turned out beautiful however the steel was too gummy and created too much static friction to prove useful for precision rotation, so now it sits on my desk as a really nice very expensive paper weight.
Thanks for sharing, very helpful. Would there be any benefit of centering the Chuck ID with the face plate OD using shim stock? I’m just curious how we know if the 0.020” clearance is being optimized, ah maybe I’m being ridiculous. Thanks
Without doubt there are 'right ways' and 'wrong ways' to do any job. I watch everybody's own methods and consider how best to apply the good parts of each person's method to my application.
That's all good if you hold your parts in lathe in the back of jaws and tighten lightly, as you did when grinding. Mostly we hold parts in the front when turning ...the jaws need to be tighten allot more then grinding, you need to mimic this when grinding jaws. As jaws need more clamping power in front, the pre load needs to be in the front...I do this with ring and 3 dowel pins installed which go inside the jaw hole in front, [need to be loose], my Forkardt chuck have holes in hard jaws, you could drill also], some people use the jaw screw holes for mounting ring which I see only a slight problem...the jaws might slightly be binding from each other and uneven forces are applied..but with care this can be minimal and for this purpose well suited. About .003" taper to the back of hard jaws I grind or hard turn for spring back ..gives you greater clamping force in front where it's needed. When turning soft jaws very accurate, most often I use a ring with 3 - 90degree bolts installed on the side...threaded part goes inside the ring, the none threaded part goes inside front of counter bored screw holes, I can adjust easy to the size of parts turned by turning one or more screws in or out ...close to part size, [closer the better] very minimal of turning out soft jaws.
Any issues with the diameter of the grinding wheel making a concavity on each jaw with a really small radius? I ask since you will likely be holding much larger round stock during daily use. That means that on parts larger than the grinding wheels each jaw will have 2 point of contact instead of 1 point.
Mr. Bailey, I would think that this process would work well with a non-adjustable 3 jaw chuck on a lathe with a tool post grinder. Are there any concerns you would have doing it this way?
The biggest problem with 3 jaw chucks is the float from the internal spiral plate so cleaning and oiling the chuck from day one eliminates a lot of problems with wear and I found that just tapping into true works also just buy a new good quality chuck and cut your losses,I refused to use those bolt on jaw type chucks and so my 12 inch 3 jaw chucks ran inside one thou at all times and used older chucks for rougher jobs,horses for courses.
I used a round grind stone in my tail stock with an old 3 jaw with 10 thousands run out and got it to 3 thousands,, had to try just to see if it could work and was surprised how well,, where there's a will there's a way,, just seems using the same machine is the best way to go
If the scroll has run out then it may be in the bearing surface of the chuck where the scroll runs on. The boss that the scroll bearing surface runs on has to be machined and a ring put on it and then ground or accurately machined to be a transition fit for the scroll bearing surface for it to be accurate. If this has slop then all the amount of machining the jaws won't fix it. The hard part is accurately measuring the surface of the chuck boss to be able to get a good fit as it's deep down inside the chuck with about an inch of clearance either side. calipers aren't accurate enough so a micrometer is needed.
Thanks for this video. I have been looked at ALL the youtube vids on the subject grinding jaws and there are more than a few. It seems there is a common thread in most of these which comes around in many comments. This is that, "if the jaws are worn the scroll is as well". I personally cannot refute this claim as I am strictly a complete novice to this trade. My question to you, if I may, is: Why do all the videos show the jaws being ground with the machine spindle running? Why would it not be just as good to set up the TP grinder, in a manner that most do, and manually index the jaws by turning the chuck by hand? In other words position a jaw, then grind and move on to the next??? Thanks BTW - I am working on a 6" chuck that I have on an old Sheldon 10" EXL lathe. What I did so far was grind the removable tops using my T&C grinder. I placed all three of the jaws in a precision vise with the tongue of each jaw resting on the fixed side of the vise and ground all at once. I will mount them in the chuck and check for TIR to see if doing this gets me in the ball park. If I am .001-.003 TIR I'll live with it and expect nothing more.
Great video on a subject that affects anyone that has used a lathe very much. I would also be interested in your take/process for correcting "bell-mouthed" jaws on a 4-jaw independent chuck; an entirely different animal which seems much more difficult to preload & grind true.
+Robert Ross It will definitely help to do this on a 4 jaw chuck, but it will be challenging to position the jaws back into the same place you ground them.
These videos are great, i grind drive shafts for outboard motors on a O.D. Cincinnati grinder. I'm not to experience with grinding, been doing it for almost a year. I use a flag, dog, gauge, and steady rests (backrests). Grinding to me is very stressful. On my first grinder I have to get a wheel up to a shoulder with tolerance of 6-9 thou stock removal. Any advise on how to get the wheel to touch on the shoulder without crashing the wheel on my first part?
Why not turn the jaws? a rough finish will help grip your part better I think. It's how we do it at least. and why not indicate the chuck before grinding? i know youll take off less material but won't your chuck be running out and causing your lathe to shake at high speeds? don't want to sound smart, I'm still learning and asking questions. I subscribed thanks for the great videos!
To the Russian-----------In a large shop where tooling is passed around from machine to machine, it would be impractical to fit tooling to one particular machine and have it not fit another. This is the purpose of having the ability to adjust your chuck to each machine any time.
You need to tighten the jaws on the slug with the one of the pinions on the chuck that's marked with a zero (0). Some chucks don't have it and if they don't, and you are grinding a chuck without it, designate one by stamping a zero beside it preferably before mounting it on the grinder. Then use it to tighten the slug and future work-pieces that need near minimum zero run out.
Not necessary on a chuck like in the video, as it is an SetTru style chuck which can be dialed in with those setscrews. On non-adjustable chucks it is a good idea, but don't just blindly follow that advice. I have found many chucks that will give you different runouts on differents diameters depending what chuck key hole you use. This means that the scroll has worn a bit and can cock inside the chuck, making the jaws move one way or the other. On a worn chuck you can tap the jaws with a piece of copper to move the jaws into alignment, basically pushing the scroll the way you want.
my chuck is off, been trying to figure out how i can fix it. the only tool i have that can do it is a 1/4'' milwakee diamond bit. its a mini lathe, n i'm having trouble figuring out how to keep the bit perfect with the spindle. my tail isn't as solid as it could ever be, or anywhere as rigid as that machine you have.
Yes, you will. But the effect is negligible. In fact, you could end up with more bearing surface depending on how well the jaws were ground originally. Likely not all that precise. On a run of the mill 3 jaw chuck, probably not ground super co-planar to the spindle bore in the first place.
i actualy did this at my work, but if i watching things like this, i am really happy to live in europe, because number (for me its not really a true number) like "1/1000, 2/10" just blowing my mind ... For me is it like 1/1000 is 0.001 and 2/10 is 0.2 (is not really but you get the idea) and for grinding diameters is this very significant difference between those sizes of diiameters.
good stuff...question regarding resurface the mag table on the surface grinder!does it matter if the mag is on or off?my thought is on...considering that's the condition while grinding! but...
Nemo Cacihlas make sure it is on, this is because when holding .0001 inch your magnetic strips will move a few tenthousandths so you need to make sure the magnet is pulling it in the same was as when grinding. When you are done you want to do a five block tests to verify accuracy
You have one thing right you must have pressure of jaws in the direction your going to clamp parts. The way I do it is set jaws to your diameter then make a ring that that you can bolt thru using the outer bolts that hold the two piece jaws on then tighten chuck that way you can grind all the way thru chuck jaws.
Perhaps you can explain, but if you grind the master jaws when the chuck isn't preloaded, then you preload the master jaws and grind the top jaws, the loads can be uneven on the jaws because the scroll wasn't preloaded during the master jaw grinding. Every tutorial I've seen on grinding jaws starts with taking the lash out of the scroll to ensure you aren't grinding one jaw more than the others. Yes, I realize you were using a brand-new chuck, and perhaps that influences your technique, but I'd like to hear your explanation for not preloading the master jaws with a clamp ring. Also, do you touch up the top jaws for every part, to ensure utmost accuracy, or do you just chock up any error to "within tolerances"? I'm surprised to see a 3 jaw used for a final grind, or is it typical to grind the ID first, then use the ID as the locating feature for OD grinding?
+eformance The first grind was a relief grind. After the relief was put in, the jaws were preloaded and ground. It all depends on the parts being ground and the tolerances as to when we grind the jaws.
Sir , you can not imagine how helpful your tutorial has been to me . THANK YOU VERY VERY MUCH!!!!!
You're welcome! Thanks again for watching, we appreciate it.
Ohh not only watching, subscribing and recommending to machining fellows. Excellent info and very well explained. Super grateful!
Cheers!
Mars Alexandre ""
I learned that from a toolmaker 30 years ago. My chuck on the lathe still good, first tighten to 2-3 microns!. The important thing is to always tighten in the same chuck key hole, so that the scroll is in the orientation, internally as when jaws were first ground. As well as grinding the jaws, I used a mild steel bar in the tailstock, grinding paste, and did final lapping finish on the jaws, tightening down on the bar and grinding paste. As long as jaw numbers are always sequenced the same, works a treat! Can get better than that, with the soft hammer, as it is tightened. 2-3 microns is perfect for most jobs in the lathe, (and I have a tool post grinder, too).
Hope this helps ;)
Hi Don,
Great video and excellent results! Thanks for sharing.
Regards,
Ray
watching that indicator barley move after grinding the jaws was AWESOME!
Don Bailey is a true inspiration. I hope to have the privilege of meeting you someday, soon.
Thank you for your kind remarks!
I've watched several videos on truing a 3 jaw chuck. I saw this one with the Suburban Tool Inc. name and knew I was going to see the right way to do it.
I am learning a lot from these videos, we have never have an opportunity to work with talented and experienced people like Don, he is a real master of these kind of work
That is such a great lesson! This is why I love learning form experienced old timers! I would have never figured that one. In our shop, we always just cut jaws to fit whatever job we're running if it's critical. I can't ever recall a single time in over 8yrs working there, anyone ever doing such a method. Then again, it would be such overkill for the work we get. Very cool lesson Mr Don! Highly appreciated! 😊
Have seen similar done in another video - but they removed 1 bolt from each jaw, fitted a longer bolt in each jaw and used those to clamp a machined ring - so the jaws are all under normal tightening tension without the normal jaw faces being obscured - so the full length of the jaws can be ground.
Nice discussion and demonstration, Don. Many thanks.
2:16 he played it off very well. Love your vids always are packed with useful information.
At 2:14 seconds when he pauses to say "about" you can hear the man Crack a rat. I'm dying laughing right now.
I was all set to grind my three jaw and watching how others did it because I was convinced that is what I had to do. Then I watched this video and saw the method of truing the chuck to the back plate. No grinding needed after that I was shocked, thanks very much for that.
Thanks for watching!
For all those wanting to know a setting ring is the way to ensure you machine jaws under the correct vector Look up Hass how to cut soft jaws this will help in understanding.
A 3 jaw is only going to be as acurate as the scroll and guides so beware of constantly grinding hard jaws to gain accuracy at different diameters, soft jaws are available for most chucks and are a lot cheeper.
Your right that's another approach.
Man this guy is awesome. You can tell he loves what he does. GREAT video!!
A great video, it teaches a concept that can be applied to a variety of setups.
Excellent video!
After 55 years of lathe maching. Listen to this. Even four jaw Chucks can use this method. Have a plate made which has 4 jaw and 3 jaw holes drilled into it at proper diameter.and on the outter bolt holes of your chuck. remove the allen head bolts and put a bolt in there to tighten the jaw. clamp in that ring hard what preasure you will be using for your prodject. then grind the inner face of the jaws. What you will find is perfection. Remove the ring and replace the allen head bolt. Thanks for allowing me to imput.
This is probably the most accurate and most professional way that's true but wrong or right is not the question also other ways work but not so precise if not done properly... This is a very good way to come to the goal...
Good little Video. I'm getting ready to do mine now on my LeBlond Lathe with an L0 Chuck.
Thank you for sharing that😊 These days I wire EDM a hole in a 1” thick plate to a wring or light press fit to the OD of my bushing, install it in the plate, then wire EDM the ID. Good size control and dead zero concentricity & taper. Or a specific taper if I want. Always good to know the alternative ways if you have certain equipment - yours is timeless 👍
Actually a great explanation! Thanks!
The chuck will grip better and run truer by loading the jaws with a hollow ring with 3 pins that fit into the inner bolts that hold the jaws on. This makes the jaws spring outward like they will under gripping pressure when holding a short part that only engages the tip of the jaws. When the jaws are ground like this you can see the tip of the jaws engage the part first and then as you increase the chucking pressure you see the jaws finally engage the part at the back of the jaws. This will make a chuck perform unbelievably better especially on lathe work with a lot of part hanging out of the chuck. The difference has to be experienced to be believed!
+ROBRENZ Our application was for an ID grinder and part specific. You technique would work well on a lathe. great comment and thanks for watching.
+SuburbanTool Inc IMO other than gripping force, chucking techniques are the same for turning and grinding. A chuck will always perform better by loading at the nose of the jaws. I am not trying to be a know it all Jerk, but a lot of beginners watch these videos and I think it is important to point out nuances of technique that will help them as all of your videos do.
SuburbanTool Inc
I do not have a grinder I could attach to my carriage, so one at a time I aligned my jaws with an indicator, in a vise, on my milling machine. Then in the mill's spindle, using a grinding wheel I had previously dressed true, I removed the necessary amount from the jaws. I brought the runout down from .012 to .001
Needless to say I was very happy that it worked. This is certainly not the preferred method, but it was the only one I was able to implement.
+ROBRENZ We thank you for your comment and concern however,we were size specific. That is we have a 1" dia. part and we grind at 1". If you grind the jaws at 1" and then chuck up a 2", 3" , 4" part there will be error due to the inaccuracy of the scroll.
+SuburbanTool Inc I agree completely with those comments and that is not what I am nitpicking about. My point is that loading the master jaws while grinding the jaws does not simulate the jaw forces and deflections that occur while gripping the part. That is why loading the jaws at the nose with a standard chuck jaw boring ring will give more stable gripping with less pressure. Haas has 2 excellent videos on YT on proper soft jaw turning and boring techniques that show the point better than my explanation. Thanks for not just deleting my comments and being willing to have discussion.
Thanks for the video. Very helpful. Thanks for sharing.
Beautiful video!
Thank you for video.
Greatly explained process:)
Hey Don ! You sir are a natural . Thanks for the great explanation.
I appreciate that!
Nice work. A grinder is an expensive item for a home shop guy like me. I like my 4-jaw. Thanks for the video.
Great information. Thanks a million.
Good show Don. thanks for sharing
Good tutorial. If only more people knew this, but then again the sale of new chucks might suffer.
Greetings from Oz again--Don that was so very very good---that sort of accuracy from a 3 jaw---I would not have believed it....Keep up the vids,if you have got time to make them I sure have got time to watch them..I am going to watch this vid again..
I just found you guys 2-15-2016.. I have had a great time watching and learning from your videos! Thank you for the information, especially this video (so far, I have many many more to watch yet, lol). Every time I have ground my jaws, I would still have about [0.001"] of total run out. Due to how I would grind the I.D. clamp area, all the while having applied O.D. force on the jaws. I now know why and where this run out is coming from, it is coming from the scroll indifference's. This never once crossed my mind. Thank you!
Thank you Don . I need to do this operation soon on a small lathe I restored . Practical Machinist
That's the way my Dad showed me back when I was 11 years old . I'm 58 now and it still the way I do it and for lathe soft jaws as well . Old Tool Maker
JT Hay Fort Worth Texas
Nice work... that was exciting! I like the method!!
Glad you liked it!
Great video. I like the way you think. :-)
+Metal Tips and Tricks (Dale Derry) Thanks Dale , how is your shop coming?
+SuburbanTool Inc
Thanks for asking. The new shop is great. I think you will appreciate this. The grinding room should be finished this month. It will house a 6x18 Harig surface grinder, KO lee universal tool and cutter grinder, plus some smaller bench grinders, and its own 2 hp dust collecting system . All the machine have been rebuilt and are painted my favorite color for machines, high gloss antique white.
Don the next time you're in Atlanta you should come by.
Thanks Dale d
Thank you for your advice. I needed to do this to my 2 lathes
You're welcome!
Thankyou for making those videos there very helpful
No problem 👍
fantastic video, very educational, thanks!
Glad it was helpful!
took mine from near .02 out to .0015 by using receipt paper between the backing plate and the Chuck. put a pipe in the Chuck for leverage and only one screw needs to be loosened to get paper in a position
Thank you - I needed this info!
You're welcome! Thank YOU for watching.
It was much needed for me as well, thanks !
You know your stuff Sir! I would love to work with you out in the shop.
great job !!
Great information!
grate video thanks
i think the only problem with this technique is that it depends on having a VERY VERY precise spiral cut into the jaw tensioning mechanism in the chuck ... if there's ANY deviation at all - which there likely IS - you will get different concentricity at different diameters (or?)
My chuck has this problem, spiral is not precise. I couldn't get a good concentricy
Nice work...fun to watch and learn👍👍👍👍👍👍👍👏🏻🇺🇸
Thanks 👍
I really enjoyed this video. It's very clear on the process. Hunting grinding wheels or points has been a challenge. Are there catalogs you like for grinding tools? What type of abrasives do you like to use (aluminum oxide, other)?
I could watch these videos all day long! And not even get a tad bit bored..... really great stuff I am happy to see the sharing of this information because it’s tricks and tips like this that give the knowledge hungry student of this trade one more tool added to their bag”o” tricks.
Yep, great bed time stories for grown ups! : )
great stuff, thanks!
Thanks Don!
Loved that grinder and technique, thanks for sharing and taking the time, energy and money to produce your content.
We have to keep loading content ants sharing our skills or all the new generation of skilled craftsman will only know CNC and not have a real clue to what it takes to trouble shoot and make "parts"... Or how to be "manly" (trigger warning)...
I like the Buck chucks that have 4 screws over the ones with 3 screws. The 3 screw chucks will only dial in to about .0005 and the 4 screw chucks will dial in within .0001. You are right there are several ways to do this although using an out-lock will give better results on worn out chucks.
Thankyou , a big help
video is the best... nice job. Legend has become Legancy ...!! :) Craftman from DK
I thought I was the only one who enjoyed using an ID and OD grinder haha. Haven't used one in years since I was trained on one at my old trade school. Made a rotation stage on it out of hardened 17-4 PH steel. The part turned out beautiful however the steel was too gummy and created too much static friction to prove useful for precision rotation, so now it sits on my desk as a really nice very expensive paper weight.
Thank you so much sir,
Don ur a very smart man that why u have a very successful business I wish iI could’ve worked for you how’s Glen doing
Thanks Don, you and your staff are making me a better machinist. Even if I'm a complete amateur, but hey you've gotta start somewhere right?
Thanks for sharing, very helpful. Would there be any benefit of centering the Chuck ID with the face plate OD using shim stock? I’m just curious how we know if the 0.020” clearance is being optimized, ah maybe I’m being ridiculous. Thanks
You are great
Awesome. Just awesome
Thank you for the video, you have been more than hellfull
Thank you for watching.
Without doubt there are 'right ways' and 'wrong ways' to do any job. I watch everybody's own methods and consider how best to apply the good parts of each person's method to my application.
That's all good if you hold your parts in lathe in the back of jaws and tighten lightly, as you did when grinding.
Mostly we hold parts in the front when turning ...the jaws need to be tighten allot more then grinding, you need to mimic this when grinding jaws.
As jaws need more clamping power in front, the pre load needs to be in the front...I do this with ring and 3 dowel pins installed which go inside the jaw hole in front, [need to be loose], my Forkardt chuck have holes in hard jaws, you could drill also], some people use the jaw screw holes for mounting ring which I see only a slight problem...the jaws might slightly be binding from each other and uneven forces are applied..but with care this can be minimal and for this purpose well suited.
About .003" taper to the back of hard jaws I grind or hard turn for spring back ..gives you greater clamping force in front where it's needed.
When turning soft jaws very accurate, most often I use a ring with 3 - 90degree bolts installed on the side...threaded part goes inside the ring, the none threaded part goes inside front of counter bored screw holes, I can adjust easy to the size of parts turned by turning one or more screws in or out ...close to part size, [closer the better] very minimal of turning out soft jaws.
Any issues with the diameter of the grinding wheel making a concavity on each jaw with a really small radius? I ask since you will likely be holding much larger round stock during daily use. That means that on parts larger than the grinding wheels each jaw will have 2 point of contact instead of 1 point.
Dear Sir, Thank u very much for this video.
Thanks for your comment
thanks alot, this really helped me out! good video
You're welcome! Thanks for watching.
i passed my examination test becuase of you, not bad :D
Look at that! Congrats! Keep at it.
thanks for the tip interesting
You're welcome, and thanks again for watching.
Thank you I got to do that on mine
Very nice. Now I just have to figure out how to do it on a chuck that does not have those nifty adjustment screws.
I think it would be essentially the same , as long as the true part is in the preground rear of the jaws.. then clamped..
Spot on
Thanks for watching!
Mr. Bailey, I would think that this process would work well with a non-adjustable 3 jaw chuck on a lathe with a tool post grinder. Are there any concerns you would have doing it this way?
The biggest problem with 3 jaw chucks is the float from the internal spiral plate so cleaning and oiling the chuck from day one eliminates a lot of problems with wear and I found that just tapping into true works also just buy a new good quality chuck and cut your losses,I refused to use those bolt on jaw type chucks and so my 12 inch 3 jaw chucks ran inside one thou at all times and used older chucks for rougher jobs,horses for courses.
I used a round grind stone in my tail stock with an old 3 jaw with 10 thousands run out and got it to 3 thousands,, had to try just to see if it could work and was surprised how well,, where there's a will there's a way,, just seems using the same machine is the best way to go
Gotta have a new chuck with even scrolls on each jaw to get full benefits
If the scroll has run out then it may be in the bearing surface of the chuck where the scroll runs on. The boss that the scroll bearing surface runs on has to be machined and a
ring put on it and then ground or accurately machined to be a transition fit for the scroll bearing surface for it to be accurate.
If this has slop then all the amount of machining the jaws won't fix it. The hard part is accurately measuring the surface of the chuck boss to be able to get a good fit
as it's deep down inside the chuck with about an inch of clearance either side. calipers aren't accurate enough so a micrometer is needed.
I always wondered if you could add a tenth adjustment to a 3jaw my 6jaw has one...
Thanks for this video. I have been looked at ALL the youtube vids on the subject grinding jaws and there are more than a few. It seems there is a common thread in most of these which comes around in many comments. This is that, "if the jaws are worn the scroll is as well". I personally cannot refute this claim as I am strictly a complete novice to this trade.
My question to you, if I may, is:
Why do all the videos show the jaws being ground with the machine spindle running?
Why would it not be just as good to set up the TP grinder, in a manner that most do, and manually index the jaws by turning the chuck by hand? In other words position a jaw, then grind and move on to the next???
Thanks
BTW - I am working on a 6" chuck that I have on an old Sheldon 10" EXL lathe. What I did so far was grind the removable tops using my T&C grinder. I placed all three of the jaws in a precision vise with the tongue of each jaw resting on the fixed side of the vise and ground all at once. I will mount them in the chuck and check for TIR to see if doing this gets me in the ball park. If I am .001-.003 TIR I'll live with it and expect nothing more.
Great video on a subject that affects anyone that has used a lathe very much. I would also be interested in your take/process for correcting "bell-mouthed" jaws on a 4-jaw independent chuck; an entirely different animal which seems much more difficult to preload & grind true.
+Robert Ross It will definitely help to do this on a 4 jaw chuck, but it will be challenging to position the jaws back into the same place you ground them.
These videos are great, i grind drive shafts for outboard motors on a O.D. Cincinnati grinder. I'm not to experience with grinding, been doing it for almost a year. I use a flag, dog, gauge, and steady rests (backrests). Grinding to me is very stressful. On my first grinder I have to get a wheel up to a shoulder with tolerance of 6-9 thou stock removal. Any advise on how to get the wheel to touch on the shoulder without crashing the wheel on my first part?
Why not turn the jaws? a rough finish will help grip your part better I think. It's how we do it at least. and why not indicate the chuck before grinding? i know youll take off less material but won't your chuck be running out and causing your lathe to shake at high speeds?
don't want to sound smart, I'm still learning and asking questions.
I subscribed
thanks for the great videos!
To the Russian-----------In a large shop where tooling is passed around from machine to machine, it would be impractical to fit tooling to one particular machine and have it not fit another. This is the purpose of having the ability to adjust your chuck to each machine any time.
Totally agree with indicating the chuck before grinding the jaws. Indicating the jaws does not make sense.
I agree indicating the chuck first then indicating the jaws to find the difference before grinding.
I might do this on my home 3 jaw, Ill need to get a grinding wheel capable, suggestions ?
Wonderful
Thank you! Cheers!
You need to tighten the jaws on the slug with the one of the pinions on the chuck that's marked with a zero (0). Some chucks don't have it and if they don't, and you are grinding a chuck without it, designate one by stamping a zero beside it preferably before mounting it on the grinder. Then use it to tighten the slug and future work-pieces that need near minimum zero run out.
Not necessary on a chuck like in the video, as it is an SetTru style chuck which can be dialed in with those setscrews.
On non-adjustable chucks it is a good idea, but don't just blindly follow that advice. I have found many chucks that will give you different runouts on differents diameters depending what chuck key hole you use. This means that the scroll has worn a bit and can cock inside the chuck, making the jaws move one way or the other. On a worn chuck you can tap the jaws with a piece of copper to move the jaws into alignment, basically pushing the scroll the way you want.
Thats is the raly right trick . i am also using this method from a long time approx from 1995
Grate Please wacthing this video , many thanks Sir for sharing your knowledge.
You are most welcome
my chuck is off, been trying to figure out how i can fix it. the only tool i have that can do it is a 1/4'' milwakee diamond bit. its a mini lathe, n i'm having trouble figuring out how to keep the bit perfect with the spindle. my tail isn't as solid as it could ever be, or anywhere as rigid as that machine you have.
How far off is your chuck and what type of work are you doing? Thanks for watching.
If you relieve the back of the jaws then won’t you lose some of your clamping surface?
Yes, you will. But the effect is negligible. In fact, you could end up with more bearing surface depending on how well the jaws were ground originally. Likely not all that precise.
On a run of the mill 3 jaw chuck, probably not ground super co-planar to the spindle bore in the first place.
Most informative. Unfortunately I have no ID grinder.
+ChrisB257 Use a Dumore grinder on the lathe bed.
i actualy did this at my work, but if i watching things like this, i am really happy to live in europe, because number (for me its not really a true number) like "1/1000, 2/10" just blowing my mind ... For me is it like 1/1000 is 0.001 and 2/10 is 0.2 (is not really but you get the idea) and for grinding diameters is this very significant difference between those sizes of diiameters.
2/10 is = .0002 [ 2 ten thousands of a inch ... bit of a slang term. }
Why the green screen? Does make the sparks look awesome!
I have a 40 year old asian gear head lathe 13" X 36" I use in my garage.
Is .005 runout normal for my 3 jaw chuck?
I can't comment on the runout, does it do the job? Thank you for watching!
good stuff...question regarding resurface the mag table on the surface grinder!does it matter if the mag is on or off?my thought is on...considering that's the condition while grinding! but...
namba
Nemo Cacihlas make sure it is on, this is because when holding .0001 inch your magnetic strips will move a few tenthousandths so you need to make sure the magnet is pulling it in the same was as when grinding. When you are done you want to do a five block tests to verify accuracy
When I had to bore jaws that’s how I did it !
I agree..This is the Best way
U.S. Patent No. 2,639,157 to Buck, et al.; issued 1953.
You have one thing right you must have pressure of jaws in the direction your going to clamp parts.
The way I do it is set jaws to your diameter then make a ring that that you can bolt thru using the outer bolts that hold the two piece jaws on then tighten chuck that way you can grind all the way thru chuck jaws.
Perhaps you can explain, but if you grind the master jaws when the chuck isn't preloaded, then you preload the master jaws and grind the top jaws, the loads can be uneven on the jaws because the scroll wasn't preloaded during the master jaw grinding.
Every tutorial I've seen on grinding jaws starts with taking the lash out of the scroll to ensure you aren't grinding one jaw more than the others. Yes, I realize you were using a brand-new chuck, and perhaps that influences your technique, but I'd like to hear your explanation for not preloading the master jaws with a clamp ring.
Also, do you touch up the top jaws for every part, to ensure utmost accuracy, or do you just chock up any error to "within tolerances"?
I'm surprised to see a 3 jaw used for a final grind, or is it typical to grind the ID first, then use the ID as the locating feature for OD grinding?
+eformance The first grind was a relief grind. After the relief was put in, the jaws were preloaded and ground. It all depends on the parts being ground and the tolerances as to when we grind the jaws.