Sir , you can not imagine how helpful your tutorial has been to me . THANK YOU VERY VERY MUCH!!!!!

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

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! 😊

Don Bailey is a true inspiration. I hope to have the privilege of meeting you someday, soon.

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 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

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.

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.

watching that indicator barley move after grinding the jaws was AWESOME!

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!

Nice discussion and demonstration, Don. Many thanks.

2:16 he played it off very well. Love your vids always are packed with useful information.

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...

A great video, it teaches a concept that can be applied to a variety of setups.

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 👍

Great video. I like the way you think. :-)

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.

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.

Hey Don ! You sir are a natural . Thanks for the great explanation.

Thank you Don . I need to do this operation soon on a small lathe I restored . Practical Machinist

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!

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..

Good tutorial. If only more people knew this, but then again the sale of new chucks might suffer.

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

Man this guy is awesome. You can tell he loves what he does. GREAT video!!

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 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.

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

At 2:14 seconds when he pauses to say "about" you can hear the man Crack a rat. I'm dying laughing right now.

Excellent video!

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.

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.

Good little Video. I'm getting ready to do mine now on my LeBlond Lathe with an L0 Chuck.

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?)

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 the video. Very helpful. Thanks for sharing.

Nice work. A grinder is an expensive item for a home shop guy like me. I like my 4-jaw. Thanks for the video.

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.

Great information. Thanks a million.

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.

Actually a great explanation! Thanks!

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

Very nice. Now I just have to figure out how to do it on a chuck that does not have those nifty adjustment screws.

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!

Most informative. Unfortunately I have no ID grinder.

Thank you for your advice. I needed to do this to my 2 lathes

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.

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)?

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.

Gotta have a new chuck with even scrolls on each jaw to get full benefits

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

Thats is the raly right trick . i am also using this method from a long time approx from 1995

Good show Don. thanks for sharing

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.

Nice work... that was exciting! I like the method!!

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)...

Beautiful video!

Dear Sir, Thank u very much for this video.

not a big fan of clamping the jaws inside the chuck to get them running true, especially when the chuck was already used for some time. the t-guidances might have worn out by then, and all you'd achieve is to have a taper on the jaws resulting in poor stabilization of longer parts and they would never run true. what i do on my lathe is to get a new set of (hardened bloc) jaws, bore a small hole in the most protruding surface in all of them at roughly the same position and insert a bolt of the same diameter in order to clamp a machined ring. with that you got the clearance to grind/turn the ID of the jaws all the way through just perfectly the way they would bend out naturally inside the t-guidances of the chuck and without any taper by default. i actually performed that recently on a 15 year old 10" chuck, and the runout on a most precise carbide shaft with .45" diameter was below a third of a thou with no significant taper on about 4 inches away from the jaws. worked everytime so far.

When I had to bore jaws that’s how I did it !

great stuff, thanks!

video is the best... nice job. Legend has become Legancy ...!! :) Craftman from DK

Thank you for video. Greatly explained process:)

You know your stuff Sir! I would love to work with you out in the shop.

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.

Great information!

Thankyou for making those videos there very helpful

Nice work...fun to watch and learn👍👍👍👍👍👍👍👏🏻🇺🇸

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.

grate video thanks

Thank you - I needed this info!

fantastic video, very educational, thanks!

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?

Thanks Don!

U.S. Patent No. 2,639,157 to Buck, et al.; issued 1953.

Thank you so much sir,

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.

If you relieve the back of the jaws then won’t you lose some of your clamping surface?

Why the green screen? Does make the sparks look awesome!

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?

Thank you I got to do that on mine

Grate Please wacthing this video , many thanks Sir for sharing your knowledge.

Thankyou , a big help

Awesome. Just awesome

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?

Thank you for the video, you have been more than hellfull

Won't work very well with cheap chinese mini-lathe chucks where the scroll has .003" runout. Now that, I would like to see a solution for!

great job !!

thanks alot, this really helped me out! good video

You are great

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

Spot on

You don't say how the backing plate was held in place?

this is what i would work with the rest of my life...

Did you green-screen in the background?

I agree..This is the Best way

I always wondered if you could add a tenth adjustment to a 3jaw my 6jaw has one...

If you could start all over again what would you do different in life and business?

thanks for the tip interesting