# 3 Jaw chuck broken



## dbq49 (Aug 17, 2014)

:thinking:I am just starting to get my Atlas 10"-48" up and running.  I have finally gotten most of my tooling and I found sites saying that a check bar is useful in resetting the tail stock when I need to.  I started making the bar and I could not get my 3 jaw chuck to work correctly.  It would not let me unchuck the metal.  I could only rotate the chuck key one turn.  I took the chuck off the lathe and started to  disassembled the chuck.  I got it apart and found hardened lube every where.  I had to chisel the lube from everywhere.  Yes I had chips, grit, and hard chunks of lube in the workings.  What found in the ring was a tooth from the chuck gear stuck in the ring.  The only thing that I had done to the chuck was fill it with oil and wiped it down.  The tooth slot looks like it must have happened some time ago, no shinny metal.  The chuck only has the numbers 6613-1 on it.  No manufacture name.  Long question short.  Can I get a part, have it made, take my mig and weld a tooth and regrind, or pitch it?  I am going to try to post a pic.  I know you have ideas.  Lets hear what you have to say!
As always thanks!


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## pineyfolks (Aug 17, 2014)

*Re: 3 Jaw chuck briken*

Braze it and file to fit unless you have a mill, cutters, index head, and whatever else you might need. Then I'd probably still just braze it. I don't think mig is the way to go here but I'm no welder.


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## Terrywerm (Aug 17, 2014)

*Re: 3 Jaw chuck briken*

I agree with Bill, clean it up and braze in a small piece of stock, then file it to shape to match the other teeth. It may sound like a lot of work, but it will go faster than one might think.


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## mattthemuppet2 (Aug 18, 2014)

*Re: 3 Jaw chuck briken*

If it's that beat up I wonder what the rest of of it will be like. Might be worth writing while you're ahead and getting a new chuck if funds allow.


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## dbq49 (Aug 18, 2014)

*Re: 3 Jaw chuck briken*

Yes I can braze it.  I failed to mention that I had the tooth, it was still in the mating plate.  The plate looks good.  I think that the gear was running up against the embeded sheered tooth and that is what stopped the jaws from moving.  It is why I tore the chuck apart.  Back to repairing, brazing would be softer than the mig welding since I would have to grind/file the finish anyway.  Dose anyone know who makes the chuck with "6613-1" on it?  My parts list for the lathe does not mention anything with that number.


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## dbq49 (Aug 18, 2014)

*Re: 3 Jaw chuck briken*

Just a thought, how about just putting it all back together and see.  8/7 teeth meshing with 80 teeth on the ring.  I do not have a v/h mill to recut teeth, just some files, grinders and a dremel with diamond cutters.  I was thinking that if I brazed a tooth that I would have to place some kind of blocker at the top and bottoms of the teeth to keep it from running on unwanted areas.  What could I use as a blocker that would not get fastened to the gear it self.  What say you brazer's. 
Still thanks.


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## ScrapMetal (Aug 18, 2014)

*Re: 3 Jaw chuck briken*



dbq49 said:


> Yes I can braze it.  I failed to mention that I had the tooth, it was still in the mating plate.  The plate looks good.  I think that the gear was running up against the embeded sheered tooth and that is what stopped the jaws from moving.  It is why I tore the chuck apart.  Back to repairing, brazing would be softer than the mig welding since I would have to grind/file the finish anyway.  Dose anyone know who makes the chuck with "6613-1" on it?  My parts list for the lathe does not mention anything with that number.



I found a reference for a 6" chuck "made in England" with that serial number - 





> 230A.   6” close to new, outside jaws only, integral 1 ½  x 8 back, #6613-1 made in England, $145.00


.  My assumption from that would be that it is a Pratt Burnard chuck (or most likely just a Burnerd depending on age).

I also found this listing for Atlas chucks where there is a listing for a 6" chuck model #6613




Hopefully some of that will give a clue as to it's origin.

-Ron


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## chips&more (Aug 18, 2014)

*Re: 3 Jaw chuck briken*



dbq49 said:


> Just a thought, how about just putting it all back together and see.  8/7 teeth meshing with 80 teeth on the ring.  I do not have a v/h mill to recut teeth, just some files, grinders and a dremel with diamond cutters.  I was thinking that if I brazed a tooth that I would have to place some kind of blocker at the top and bottoms of the teeth to keep it from running on unwanted areas.  What could I use as a blocker that would not get fastened to the gear it self.  What say you brazer's.
> Still thanks.




I would not put it back together with the missing tooth. Chances are it would bind up where the tooth is missing and you would then break more teeth off. I would with your Dremel and an abrasive wheel and a steady hand grind a slot the width of the tooth and say about 0.100” deep right in the center of that broken area. Then get a piece of steel the width of the tooth and length and all of that and braze it in place. If the steel blank is a little too thick don’t file it down, but instead hit it with a hammer and smash it thinner. After all has cooled. Then grab that Dremel again and with your steady hand shape the profile of the tooth and maybe a little filing too…Good Luck.


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## Tony Wells (Aug 18, 2014)

*Re: 3 Jaw chuck briken*

I'd look at a different approach, under some circumstances. If this chuck has only the one pinion, then obviously this will be no help. I would make a blank, sans any gear teeth and just use one of the remaining 2 to tighten the chuck. Then I would shop for another chuck. In the mean time, unless there were high speed balance issues, I'd use as is.


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## dbq49 (Aug 18, 2014)

*Re: 3 Jaw chuck briken*

Great effort Ron!!!  I did find a "made in England" on the back.  After cleaning all the gunk from the inside, I wire wheeled the jaw, polished the ring and tried the fits.  I found that the jaws would not slide in the grooves.  I had to take the dremmel and a thin metal cutting disc and deburr all the parts till they slid easily.  I was surprised how much better is works now.  60 years of binding??  I am still trying of figure out if I want to braze in a tooth.  The broken tooth fits well but getting it to sit there while I braze it is an other issue.
Thanks to all that are helping!


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## machinist18 (Aug 21, 2014)

*Re: 3 Jaw chuck briken*

Do you know anyone with a TIG welder. If so have him build up the area of the broken tooth, then anneal the part. you can then use a die grinder or files to shape the tooth until it fits then reharden it again. I've done it so I know it works,


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## dbq49 (Aug 30, 2014)

*Re: 3 Jaw chuck briken*



machinist18 said:


> Do you know anyone with a TIG welder. If so have him build up the area of the broken tooth, then anneal the part. you can then use a die grinder or files to shape the tooth until it fits then reharden it again. I've done it so I know it works,



I have mig welder not a tig unit.  It was my hope to do just that and grind in the tooth profile.  Yes, annealing the weld will make it possible to shape the tooth.  Are pinions hardened?


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## xalky (Aug 30, 2014)

*Re: 3 Jaw chuck briken*



dbq49 said:


> Great effort Ron!!!  I did find a "made in England" on the back.  After cleaning all the gunk from the inside, I wire wheeled the jaw, polished the ring and tried the fits.  I found that the jaws would not slide in the grooves.  I had to take the dremmel and a thin metal cutting disc and deburr all the parts till they slid easily.  I was surprised how much better is works now.  60 years of binding??  I am still trying of figure out if I want to braze in a tooth.  The broken tooth fits well but getting it to sit there while I braze it is an other issue.
> Thanks to all that are helping!



If the broken tooth fits well, why cant you just clamp it lightly so that it doesn't move, then braze it. Thou could also v out the sides a little with a small dremel grinder , maybe ....to get some braze ,metal in there. Just a thought.


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## Charles Lessig (Oct 19, 2014)

*Re: 3 Jaw chuck briken*

I had a Made in England chuck with the same problem. I found a Jacobs chuck key almost the same size as the broken pinion
that would fit in there. I took off the handle and let the stub stick out of the chuck. It was tightened with a rod that fit the hole.
It stuck out but was not worse than some four jaw chuck set ups. It worked as well as it did before.


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## george wilson (Oct 19, 2014)

*Re: 3 Jaw chuck briken*

I agree with Tony: If the chuck has 3 tightening pinions,leave that one without teeth and tighten the other 2.

No reply on that yet. 

I don't think a brazed tooth is going to hold together. If this is the only pinion,I would get a new chuck.

Clever use of the Jacobs chuck key. Could be dangerous though. I'd bet it would not fit the scroll real well,though,and could damage it. Not that that mattered,if you can't find a new part anyway.


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## Kernbigo (Oct 19, 2014)

don't braze it silver solder the tooth back in it will work fine,silver has a lot more strength than brazing. Use a piece of silver flatten out under the tooth, don't forget the flux, and clamp it.


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## Brain Coral (Oct 19, 2014)

*Re: 3 Jaw chuck briken*

Have a look at this company... they sell all kinds of replacement parts for Pratt Burnerd chucks. I ordered an operating screw for a PB 4-jaw chuck last week and it arrived in a few days. If the chuck is in, otherwise good condition, this might be another option for you.

http://www.rotagriponline.com/index...tegory_id=206&option=com_virtuemart&Itemid=29

Cheers... 

Brian


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## george wilson (Oct 20, 2014)

*Re: 3 Jaw chuck briken*

Brain Coral,that is a very useful link,provided they have the exactly correct pinion. The trouble is,England has not instituted some HIGH minimum shipping rate ($20-$30 minimum???) Someone correct me,please.

This means,if you don't know the exact model of the chuck,you will end up with over $60.00 invested,just to get a look at the pinion they send you. That one in the picture isn't his correct one,either.

One time I was trying to buy a set of 6 jaw chucks from an American company. They sent the wrong jaws twice before they got it right. At least shipping wasn't overseas. 

Seems to me that England is hurting commerce by putting such a high fee on shipping. I have turned down a few nice antique chisels or other fine woodworking tools on Ebay(from England) because of the new sky high rates. They would have doubled the already stiff prices!

Look up the conversion rate of dollars to pounds before you buy anything. Last time I checked,it was about 1.62 for 1 American dollar,but it changes.


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## Brain Coral (Oct 20, 2014)

*Re: 3 Jaw chuck briken*

Hello George,

The example of a pinion that I provided a link to was, just that... an example... There are very detailed drawings and specifications to find what you are looking for on the website. When I first emailed the company with the model and serial number of the chuck, I was informed that this information was meaningless to them. They did provide a link to what they thought would be the part I was looking for and requested exact measurements to verify... and it was exactly what I required. If you take some careful measurements of an existing part, they will likely have what you need. 

I agree that it isn't cheap, but if you really need that part.... shipping..... for me it was cheaper than most shipping costs on Ebay from the U.S to Canada. The 4-jaw chuck that I have is in real good shape other than the one operating screw. Me thinks that someone left the chuck key in the chuck and then turned it on... :yikes:

I must admit, the part sent to me was very serviceable and fit the chuck, but was a little rough in the finish. I had to deburr the part before installing it.

Cheers... 

Brian


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## Kiwi (Dec 27, 2014)

Sorry to drag an old thread up. I was about to go through the same process but managed to sort out the problem I had with a 3 jaw Burnerd  chuck I was under the impression that  prat Burnerd was taken over by the 600 group and that parts for the their chucks were still supported  IE the number stamped into the jaw slot matched the number on the jaw allowing for replacement jaws, scrolls etc however on my chuck the scroll has an engraved number on it that is different to the body number and jaw no in my case this old lathe is new to me the chuck would bind, take the jaws out and it was nice and the jaws were nice, scroll problem! found some damage to the lead of the scroll and about 15 mill in from the lead so I suspect that the previous owner had impacted the out side jaw when it was on the last  turn on outside of the scroll. The out side jaws did not come with the lathe. I was waiting for the Christmas break to finish before contacting the 600 group to get replacement outside jaws and just cleaned up the lead with a file and filed off the lump 15 mill in reassembled the chuck with a little smear of copper coat on the rubbing surfaces and runs like silk now


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## phill05 (Dec 29, 2014)

*Re: 3 Jaw chuck briken*



george wilson said:


> Seems to me that England is hurting commerce by putting such a high fee on shipping. I have turned down a few nice antique chisels or other fine woodworking tools on Ebay(from England) because of the new sky high rates. They would have doubled the already stiff prices!
> 
> Look up the conversion rate of dollars to pounds before you buy anything. Last time I checked,it was about 1.62 for 1 American dollar,but it changes.



Hi 
I live in the UK and not all shipping companies charge big bucks I just sent a 1.5kg package to Canada 3 days by air for £14 or $22.

Phill


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