MACHINE SHOP TIPS #147 Grinding the Jaws on a 3-Jaw Chuck tubalcain

Video quality	The size	Download

Информация о MACHINE SHOP TIPS #147 Grinding the Jaws on a 3-Jaw Chuck tubalcain

Название	:	MACHINE SHOP TIPS #147 Grinding the Jaws on a 3-Jaw Chuck tubalcain
Продолжительность	:	24.06
Дата публикации	:
Просмотров	:	457 rb

Always knew of the problem , thanks Pete From Old New Orleans 🤓
Comment from : JAMES TREGLER

I have a question as a novice, I have a chuck that runs out of true, however to purchase all the grinding gear would be far too expensive for myself I presume that one's chuck must be ground on ones own lathe, how is one supposed to do this without the machinery I am presuming that not all Lathe owners posses all this machinery
Comment from : Arbe

Keith Fenner blew my mind when he leveled a lathe in one shot with MATH lol the dude is on another level
Comment from : GsdTdeaux7

I had this bell mouth issue on the center of a 4 Jaw chuck I used a large outer bearing race ring to load the jaws on a outer chuck step Center Indicated the race ring and ground the bore much like you did and now both steps are true to each other
Comment from : Eng Tech

Bowels of the Chuck? But the JAWS are bellMOUTHED If it’s the bowels, that must mean you are talking out of your arse 😂
Comment from : Made In Great Britain

Awesome So how do you grind independent jaws for parallelism? brbrEdit: I don't know if independent jaws need grinding I just got my new independent chuck Haven't installed it yet Sorry if it is a silly question
Comment from : Suat Korkmaz

'sneak the towels into the laundry' Either she's a very understanding wife, or she already knows you're hopeless, or you just like to live dangerously 👍
Comment from : KingLoopie1

Replacement Jaws would work if you not to thrifty
Comment from : Jerry Gustin

Excellent explanations Thank you
Comment from : Etienne Benade

Hello Sir! My Atlas (10") 3-jaw chuck is suffering from substantial bell-mouth - and I have no tool post grinder, though I might be able to rig something up What would you recommend?? Thank you in advance
Comment from : cpasseno

Hey Lyle, I find that when the jaws are in bad shape, it's because the scroll gear is worn along with the jaw guides machined into the chuckbrIn other words, overall wear of the chuck Grinding the jaws will be exact only in the position they are ground at Sometimes the jaws wear at the outer ends because the slop in the chuck allows them to get cocked in the guides The best defense is to always cover the length of the jaw with your workpiece Gripping on the end of the jaws only causes problems in the future Thanks for the videos, I look forward to watching them
Comment from : T D Mich

10:00 perhaps the grinding dust wouldn’t be drawn into the fan if the cover was in place? 🙂
Comment from : SJV

It's also not funny that you would have a cloth so close to a revolving chuck Is this another joke?
Comment from : Penta Comstat

Your Stalin joke is so impossible it's not even funny
Comment from : Penta Comstat

I think maybe the runout you see on the indicator is not a runout on the chuck, but a little worn spindle bearing Because when you put your hand on the chuck to turn it, the indicator moves a little to the left, but it goes back again when you let go of the chuckbrBut thank you very much for good videos I have an old South Bend model A and I have got many good ideas from you
Comment from : Ragnar Myhre

good simple tip what to look for when buying a used lathe
Comment from : dog paw

Thank You Mister Pete for all your knowldge and HELP! Regarding lathe Jaws grinding fixture ?Machine shop program at Yuba College, Yuba City California Circa 1975; Use a 3/8" thick steel plate cut the outside circle maybe 8" in diameter locate the center and drill and bore the center hole slightly larger than the jaws inside edge inside diameter which would be larger than the jaws clearence depending on the size of the cutting wheel? Next you need to scribe a circle maybe 1/8 larger from the jaws clamping surface Next you need to bore three holes at 120 degrees so they each intersect on center each jaw, when cut out each circle you can clamp the jaws down on the fixture and it is perfect you can grind all three jaws parallel and is really simple to make perfect like new jaws If there are any questions I can make a simple drawing and send it to you, please note my dimentions might be wrong as it has been 50 years since I made the last one taught to me by the Machine shop instructor MIKE that was the states transportation machinest Most sincerly your 81 years old apprentice, Raymond Brown
Comment from : Ray Brown

A Super video about grinding Jaw chuck Ciao grazie
Comment from : isoladeipirati

You preloaded the jaws way out at the maximum extent causing them to every so slightly flare out due to the leverage
Comment from : BrianRDub

What is the ratio between the two pulleys you have on your tool post grinder? If I look at the size of the pulley on the motor in comparison with the one on the grinding spindle, the grinding spindle will be spinning at quite a speed I hope people take notice of your jaw pre-load explanation Many brothers don't know what should be done before starting the grinding, or they don't care
Comment from : Pieter Botes

Great video, thanks
Comment from : Ken Curtis

I am just wondering is the Grinder motor not reversible ? it may just be wired in such a way ,
Comment from : john reimer

Did it fix your problem? Or did it spring again ?
Comment from : jeffreyrstapler

I would have just had a vacuum hooked up
Comment from : Cecil Andrews

Perhaps the belt/pulley cover could deflect the dust too?
Comment from : L Stein

might check bearings with out turning push chuck sideways lt and rt
Comment from : PAYTON MAC

Yes ! You can ! Certainly !! Tell !! The lathe CHUCK !! At 7 26 !! Has been MISUSED !! AND !! ABUSED !! BY IDIOTS !! THAT !! DON'T THINK !! VERY !! HIGHLY !! OF LATHES !! AND ! CHUCK'S !! AT ALL !!! GOOD !! OLD !! SCRAP !! METAL !! AGAIN !!! READY !! FOR !! THE !!! FURNACE !!! MELT !!!
Comment from : David Willard

I have just done a grind on my chuck jaws that had bellmouthed, , before commencing the grind I discovered that there was slacknes I the headstock bearings which I concluded mah have caused the bell mouthing, or a misaligned tailstock,
Comment from : geograph1000

You mentioned, “ranted”, in one of your videos about how disgusting an old Holiday Inn Motel can be after a different owner takes over By the look of all those brown towels that belong to your wife, it looks like you’ve been staying at Super 8 Motels and “borrowing” the towels😉
Comment from : Best Friend Hank

Thanks for the video butbrI think that preloading the jaws from one side (front) is not the same as preloading with a round stock along the jaws length and perhaps thats why there was run out after the fix , before the fix the round stock was not touching in front but did you check if they are in contact at the back after the fix?, i would have used a 025mm paper wrapped on a test bar to check if the contact is along the entire length of the jaws or not
Comment from : GraphicMan Innovations

20:06 - I'm gobsmacked - what a waste of a grinding wheel ! It appears you've got about 2 thou play in the headstock bearings ! (Either that or the chuck's loose on the spindle!)brbrI've watched a couple of vids on jaw grinding and none of them include tests on bearings or chuck alignment first The weird thing is, I've never been bothered by accuracy but it seems some people are but don't know the correct procedures for going about remedying the issue - they just seem to go in head first with jaw grinding ! At least you aren't tackling 'run out' but worn jaw ends - again though, you should have checked that the jaw tops were correctly mounted with spotlessly clean mating surfaces I'd have been particularly suspicious by the fact 2 jaws appeared worn while the third seemed fine Were the 2 that were 'out' properly mounted ?
Comment from : pmailkeey

10 minutes I can't get back just to get to the point
Comment from : George Spangler

Thank you for videobr20:45 As far as I know, turning between dead centers with rests at single mounting, provides best results for many reasons 2/3/4/6 jaw chucks are mainly convenient (cause of making proper center holes) - it is theirs main advantage
Comment from : Piotr Lenarczyk

You dont like tgat method so if you don't have these kind of chuks? Stupid
Comment from : DanF

Great video but I would not use towels under 400RPM chuck
Comment from : Jo Krol

Just saw this - Guards? we don't need no stinkin' guards! LOL
Comment from : modtwentyeight

Just a good alternate to sneaking out the brides towels, is I hit local garage sales and buy up as many FR (fire rated) blue jeans you can find The offer great protecting and besides cheap, don't have to dampen with water I also use the leg's to sew up sleeves for welding, and fender cover, ect Just a thought, but if one used a good shop vac (with dust trap) at rear of spindle, cut way down on contamination of the lathe & shop?? Bear in Tx
Comment from : Bears Rod Shop

Do the same setup but use a CBN boring tip and bore the jaws out I do mine on a regular basis and only takes a few minutes You can also get a turning tip to turn the outside of the jaws and face them true We have eliminated grinding bores by using CBN tips Just sayin'
Comment from : M Johns

Ah we know it's not 10
Comment from : fuzz32207

I have been thinking of doing that to my lathe chuck
Comment from : Guy Ward

You might want to replace the bearings on your lathe and lose 1 thau of vibration
Comment from : Icecreamtruck Og

Sirleth grinder R P M?
Comment from : Harprit Singh

Couldn't you just do an internal cut with the ring holding tention or do you have to use a grinder?
Comment from : Scott Cowen

I like you machine shop mr nice work but Hery up and wash the talls cause if not ur nex video is you funeral and want to learn more from youuuuuuu👍👍👍
Comment from : Arnie Satacruz

For one piece jaws, Scott Logan has a sketch of a jig plate for pre-loading the jaws br lathecom/tips/chuck-jawhtm
Comment from : Dan H

Well done MR Pete!! Thank you for yet another great video When my dad died I kept ALL of his machinist equipment and tools and there are 2 too post grinders I'll bet that one or more of the chucks are in need and I know for certain that many of his dead centers are in need I'll be using this video when I get back home in Montana Thank you!!!
Comment from : JC Knives

I'm telling ,lol
Comment from : 73 SUPERGLIDE

I guess if the final runout is due to different levels of wear on different points on the scroll (ie: different diameters) there's not much you can do about it I'm wondering if the ring and bolts used to tension the jaws might also be a factor If the ring OD was at all eccentric or one of the bolts was a wee bit bent the result might be a less than perfect contact between one or more of the jaws and the scroll surface you're trying to reference Would a machined true and straight ring and bolts that conform to a larger, less worn section of the scroll help to make this operation more precise?
Comment from : Blondin

newbie question if someone got time to answer: why need grinding? why not boring ? what is the difference ?
Comment from : Sirbu Constantin

wrapping a little electrical tape around the front end of the jaws also fixes this problem if you dont have access to any of this equipment
Comment from : TehCacti

Tubalcain sounds like a tube of novacain Both have a numbing effect
Comment from : bearbon2

A well thought out job
Comment from : Michael Storm

You can buy adjustable rings for pre-loading chucks when cutting your own soft jaws, same method as here basically but it's a large ring and the holes for the bolts are cut outs made in a spiral, this gives the adjustability just by turning the platebr I am not sure what chucks they are available for though but maybe could make your own
Comment from : Trevor Smales

Does the rpm matter between the lathe and grinder?
Comment from : Calvin Brown

Thanks so much for sharing your knowledge and taking the time to make such an informative video
Comment from : agylub

There was more than ONE thing aggravating me about the Clausing 5913 that I owned for 10 years The variable speed wanted to slow all the way down But I love Pete's sense of humor
Comment from : Clark Magnuson

id kill for 0015 runout on my 3 jaw, love the ring idea
Comment from : rob

I've used a similar method to true chuck jaws, and it works well, however I think people get the wrong idea about the accuracy capabilities of scroll type chucks Even a brand new 3 jaw is seldom capable of concentric accuracy inside of 003 at any given diameter, and if the scroll and jaws are worn, much worse than that, varying considerably over the scrolls adjustment range This method works great to straighten out the jaws themselves, and it will get a 3 jaw very accurate at whatever diameter the jaws were ground at Beyond that, break out the 4 jawbr Good informative video!
Comment from : Noonesfool

Hi Pete you never cease to impress me with your experience on lathe's and how to get out of difficult problems As well as resolving them So glad to learn a great deal from your channel Really am grateful to you for these wonderful teaching training videos Thanks so much Pete hope your having a wonderful day My friend
Comment from : Mark Grevatt

Mr Pete please forgive my ignorance, but why not just bore the jaws instead of grinding?
Comment from : BB KX4TQ

Excellent I need to grind the jaws on my 16" 4 jaw chuck My biggest concern was how to center and pre-load This gives my many ideas
Comment from : Mike Rippey

I'm new at this and still learning I get the basic idea of what you are out to accomplish and the remark by Mercmad hit the nail on the head about bell mouth I don't see how you are progressively increasing the diameter of your boring as you go How do you increase the diameter of the cut?
Comment from : John Ohara

strong bite on the work with a hollow grind
Comment from : Jaxx Brat

very nice tp grinderthe back end of the grinder shaft might have a center for the tailstock
Comment from : Jaxx Brat

Put a CHEAP shop-vac OUTSIDE and use a long hose to extract the dust while grindingbrYou can even get away with no filter at all using this method for maximum air flowbr(Replacing a cheap shop-vac annually is cheaper than replacing the filter often)
Comment from : Tim Dodge

HOOK UP A SHOP VAC
Comment from : Anthony Mazziotti

I've been trying to figure out a good way to do this, this is perfect Thank you!!
Comment from : Ryan

that is cool
Comment from : Sam Kim

MrPete, I thank you for the time and effort of showing this but I don't like the idea of using a grinder and/or rotating the chuck as this now creates a smaller concave surface in each jaw face, the diameter of which is equal to the jaws at the time of grinding If gripping a piece of stock smaller than the as ground diameter, you are making contact in 3 places (1 on each jaw) as the jaw is designed, but larger stock now is grabbing in 6 spots (2 on each jaw) which could lead to marking the work or runout They should be concave ground to the max diameter of the through hole on each, Though this process will correct the bellmouth issue you described, it's not a perfect solution since you are only accurate at that diameter since you still have an older worn scroll and jaw teeth The tools required to do this job could cost more than sending the jaws for precision machining or possibly buying a new chuck T
Comment from : Man Machine Make

just out of curiosity, say you didnt have the bolts in the jaws couldnt you just use a bigger disc and grab its from the outside part of the jaws? having them pushing out instead of pushing in? would that make any difference, as long as theirs stress on the jaws
Comment from : Dacoda Traeger

Hello, I am trying to figure out why you used the disc? The only thing it did, as far as I can see was to hold the jaws in an open position When the grinder went through the disc I could see what looked like a gap of an 1/8 to 1/4 inch Love to watch your videos!
Comment from : Mrx9999999

chucks get bell mouthed by not using the whole of the jaw to grip and only gripping at the tips or turning a lot of uneven pieces
Comment from : DulallyKat

If the grinder is spinning much faster than the chuck, why does it matter which way the chuck is spinning? If the grinding dust is going the wrong way why not move the grinder to the other side of center so it grinds the other way?
Comment from : Douglas Butler

My guess about inaccuracy of self centered chuck that occurred after grinding Once you have pre-stressed the jaws with a washer, I believe you have transferred inaccuracy of washer's roundness to the tips of your jaws After grinding and removal of pre-stressing washer your jaws are not of the same length anymore, hence the error in concentricity indicated by dial indicator Please express your opinion
Comment from : Nikola Radakovic

Did you check to see if the outside of the washer was perfectly round? It looked stamped out, and had burs Also, did you check that the washer sat evenly flat against evenly flat and true chuck jaws? The washer looked like it was wiggling around a little when you turned on the lathe I think there are too many variables to have to control in doing this job Add to that the fact that the spiral thing inside won't be worn evenly, as you pointed out, and this job becomes impossible Ok, so if you're just taking the taper out of the jaws this will work, but only if there's no wiggle in the jaws as they ride in their rails/grooves If there is, and there always is, you get a reverse taper in the jaws But I could be wrong
Comment from : ATINKERER

is there any other way to make a homemade lathe besides the gingery lathe
Comment from : biofall38

roughly what speed is the grinder spinning at? what speed is the chuck spinning at? Excellent video
Comment from : Val Martin

Spectacular, ?can the jaws adjust independent also
Comment from : RANDOLPH TORRES

Very smart , love these videos
Comment from : Layla Suzanne

I have been looking for this for a long time now My 5" 3-jaw Bernerd definitely needs this doing I think putting the shop-vac over the end of the spindle-hole should help stop excess grinder-grit throw-off going in the important bits I can run a flue-brush back and forth through the hole afterwards to help dislodge any bits, and suck 'em up Thanks for the idea!
Comment from : nlo114

Any ideas on how to pre-load a chuck like the southbend you showed in the video?
Comment from : pep1dog1

Hi Mr Pete, I found the best time to sneak the towels past the wife is when she is brushing her teeth :)
Comment from : Todd Anonymous

I grind lathe jaws individually I like them ground flat, I back taper them slightly to force them to grip hard on the front Three jaw chucks also wear in the jaw slides That can lead the the "bell mouthing"
Comment from : Joe McGarry

I crossed the brush wires on my 44 dumore to make it run ccw
Comment from : Danny Chavez

Dust can be blown away by a powerful fan which any shop should have for many reasons I recommend "bounce house" fans or similar capable HIGH VELOCITY blowers Other options could be a large shop vac nozzle very close to the wheel to catch dust If you put the leg of a pair of panty hose over your shop vac filter it will last much longer and be easy to clean
Comment from : Ob Fuscated