View Full Version : Need Jaws

11-03-2002, 06:44 PM
I have a Clausing 10" lathe I bought at a school auction. The 3-jaw chuck has two sets of outside jaws but no inside jaws. Does anybody have inside jaws they would like trade? The chuck has no brand marking but has the number "7" and "7060" and "Made in ENG" on the face. It is 6" diameter and 2 7/8" thick. The jaws are 2 1/2" long, 3/4" wide, with steps at 1 3/4", 1 3/8", & 1 1/16" high. There are 10 teeth on the bottom, 5/32" deep. The side grooves are 1/8" deep by 5/16" high. Any help would be appreciated. Thanks.

Ragarsed Raglan
11-04-2002, 08:27 AM

Sounds like a Pratt chuck, what is the depth from the lower tooth face to the side groove (1/8th x 5/16th dimension). I'll warn you that genuine Pratt jaws cost the Earth. I recently got around this problem by buying a set of soft jaws for my 5" Pratt chuck and machining them till they looked just like the real thing, then I case hardened them - cost £20. 'The real thing' Pratt price £120+ carriage

Remember to check the scroll for damage or wear. A new set of jaws is not always the answer to a maidens prayer when it comes to regaining accuracy! My 5" chuck was in superb condition - hardly used - but I was not going to pay that sort of money for a set of jaws if the scroll was shot to bits.

BTW £1 = $1.50ish

I can put you in touch with a company in the UK who will supply these soft jaws (or 'the real thing' if you have a fat wallet).


11-04-2002, 11:25 AM
Oh, sure, ask for the one measurement I didn't take! I can't get to the lathe until the weekend, so it will have to wait. Doesn't sound promising though, maybe I can weld and regrind the spare set and turn them into inside jaws?

Ragarsed Raglan
11-04-2002, 11:48 AM

I know, ....There's always some smart (Rag)arse!! I can find the jaw type with what you've given me - always good to have 100% information rather than 95% though!

Hell! Think of the cost of all that welding (Rods + electricity), followed by the rough fettling and finish grinding. Let me have a look to see what I have in my dead box.


11-04-2002, 11:27 PM
Thanks, RR. I wish I had a "dead box" to dig into. All I have is "inventory" that is too good to throw away, but not useful enough to keep!

11-05-2002, 01:07 AM
Sounds like a Pratt-Bernard to me too. If you know the brand of your chuck many companies sell replacement jaw sets, or if you are lucky uo may be able to replace them with a set of Master Jaws and a set of Reversable Hard Top Jaws. I would never buy any chuck with regular jaws if the Top Jaw type is available (they rock - plus they can be replaced by machinable soft jaws and large Aluminum pot jaws). If the chuck is old and crotchety consider a Bison - great chucks for the money.

Hey RR, you convince the good wife on that Schnaublin yet? I here hypnosis works sometimes... http://bbs.homeshopmachinist.net//biggrin.gif

Ragarsed Raglan
11-05-2002, 01:09 PM

I agree on the Bison chuck's - great value for money (in fact less than the replacement jaws for the Pratt would cost!). I take it by 'Master Jaws' you are referring to what we in the UK would call a 'Coventry' chuck (invented by Alfred Herberts IMMSMC). Nice chucks these ~ they fetch good money secondhand as they are quite sort after.

Been working on the hypnosis with Mrs. Raglan ~ unfortunately I don't think the snore, followed by the soft exhale and the muttered word ...S...H...A...U...B...L...I...N is working very well. I just wake up in the morning with bruised ribs and shins!!!!


11-05-2002, 11:22 PM

Check this out: www.hardingeworkholding.com/w2chucks.html (http://www.hardingeworkholding.com/w2chucks.html)
or www.jawsandchucks.com (http://www.jawsandchucks.com) or www.northfield.com (http://www.northfield.com)

Northfieled makes Diaphragm chucks with repeatability down to .oooo4"/and up to 12K rpm

Ragarsed Raglan
11-06-2002, 06:11 AM


11-06-2002, 10:56 AM
Thanks for your help. I had hoped against odds to find someone like me who had two sets of inside jaws and needed to trade for one of my sets of outside jaws. Now I hear that sharks have two sets of inside and outside teeth, but that's not quite the same and I don't like dealing with sharks anyway. The web sites you have furnished will get me on the right track. Thanks again.
By the way, the hypnotism won't work unless the subject is willing. My wife has no problem with me buying stuff and did not make a "honey-do" list when I retired. I reminded her long ago that I don't waste money on wine, women or song, fix anything around the house for free, let her buy what she wants, and most of all pointed out that I worked hard for my retirement time. It is my time, I earned it, and now that I have it only I can decide what to do with it. I will help anybody, but I owe no time to anybody else unless I chose so. I know it sounds arrogant, but I put it much more diplomatically when I tell someone in person. That is why in my retirement I now have a lathe, mill, plastic injection machine, wire feed, metal brake, etc. and a 30x60 shop to put it into. Thanks again.

11-07-2002, 01:56 AM
No problem brother - anytime. That is why we are here - to keep you guys happy, happy, happy!

Try: "Love of my life, you are so beautiful <schnaublin>, we should drop the kids at a siter and just go on a romantic <schnaublin> dinner and then a stroll by the river - your beautiful eyes <schnaublin> appear like stars in the moonlight..."

Brainwashing complete.

If that does not work I have an excellent receipe for Ginger stir-fried Yorkie - rats or cats maybe substituted (in accending order of intelligence) - that always woos 'em. http://bbs.homeshopmachinist.net//biggrin.gif

11-07-2002, 02:37 PM
I am brand new to the BBS but have a few years under my belt with HSM , just been learning from all you fine folks,THANK YOU! Last year i picked up a beautiful Royal LebLonde metal lathe to compliment my smaller atlas benchtop , I restored the machine by totally tearing her apart and cleaning and repainting, so far I am very happy to have a quick change gear box and an overall much larger lathe , I have just had a few problems , One of which is that i have a japanese "SOUL" top jaw chuck that came mounted with the machine and the top jaws are missing , i ordered a soft set from MSC , but really desire a hard set, but I can't believe the price for a hard set of top jaws , would it be worth while to machine a set of my own from tool steel or similiar? does some one have a set for a 6.5 DIA. SOUL 3 jaw chuck also I am having problems with the quick change gear box this circa 1935 lathe cuts different pitches than what i set her up to cut , It has been a real trial and error process when i want to cut say, 32 tpi , on the chart it seems to be set up for 24 tpi, could there be pickoff gears changed or missing or am i not doing something correctly thanks for your help


11-08-2002, 01:52 AM
The sites I mentioned above - in particular the Huron one should be able to help you with jaws. Just remember that the reason they are expensive is the care that is taken in matching them so they are interchangable and accurate. Once you find the most accurate paring for each top jaw mark the bottom with the jaw # so they stay together.

It sometimes makes more sense to buy a new chuck - a new Bison is often cheaper than a set of jaws for a Pratt-Bernard!

11-08-2002, 12:43 PM
Did I miss something? The "jawsandchucks" site had almost nothing I even recognized the name of, so it was a little tough to give part numbers.

What's up with that?

I was looking for a couple specific items, but there was no way to get there it seemed like. I must have had "stupid pills" for breakfast.

Peter S
11-08-2002, 06:14 PM
I dug out a Pratt Burnerd catalogue dated 1968, they have no numbers like "7060".

Their older numbers were like "58" or "78"
and post 1968 were like "1210-91705" or "1780-01605".

However, I don't know what numbers they used in later years. Pratt Burnerd make excellent chucks thats for sure. They are still around, maybe you could inquire with them?

The only other UK brand I recall using was "Taylor", but they are easy to recognize - the chuck face between the jaws is heavily scalloped/relieved. BTW, this chuck was on a Dean Smith & Grace lathe, acknowledged as the "Rolls-Royce" of lathes a few years ago...

11-08-2002, 09:55 PM
THRUD thanks for the input, I will consider the bison chuck, and just use the jap soul for soft jaw work, JON

11-09-2002, 02:56 AM

Most of the hard top jaws the average guy is apt to come accross is the "American Standard Pattern" which is used on Bison, Buck, BP, TOS, etc.

There is not much they do not sell at Huron. If you don't see it email and ask them.

The number he read could be the serial number of the chuck.

11-09-2002, 06:20 PM
Peter, thanks for the Pratt web address. Their standard 3-jaw chuck looks like mine but the specs are not quite the same, like instead of 6" diameter, they have a 120mm and 160mm (whatever mm is...) which is a little off, and there are no dimensions given for the jaws themselves. Every little bit of info helps though, and in time I think I will either find the answer or an alternative.

11-10-2002, 12:42 AM
Ah, the problem is that they deal in two-piece jaws only, and I do not have any chucks with that style jaw.

I wanted inside jaws for a 4" Buck adjust-tru, and they don't have any. I will have to try Buck-Forkardt

Ragarsed Raglan
11-14-2002, 06:07 AM

Sorry to be so long getting back to you. I have not got anything to suit your chuck ~ but the part no's you need are:-

2210-17603 Pratt original Hard inside jaw

You have outside jaws which are part no. 2210-17602.

You may be able to find in the USA a supplier of non original jaws (which I believe come from either Eastern Europe or China) which are letter coded as follows:-

Soft jaws EJG or,
Hard Bar jaws EQ16.

These are available in the UK (as are the Pratt originals) from Rotagrip Ltd. 16-20 Lodge road, Hockley, Birmingham B18 5PN Tel: 01-44-121-551-1566. Sorry there is currently no website for them.

Usual disclaimers, other than a satisfied customer.....


11-14-2002, 03:01 PM
Check a Buck Chuck catalog. These are the chucks the school got from Clausing when they delivered in 1986.

The number sounds familiar. I will check my 13 inch when i get back to work.

11-14-2002, 08:32 PM
Shaving, since you've got the extra set of jaws, could you make them into swap-tops? They might need annealed first, maybe not. Lots of the hard work done. If it doesn't work out, so what! You've gained a hatfull of knowledge and still have your chuck!

11-15-2002, 10:48 PM
Thanks again! Got some web sites to check out now, and can take another look at my spare outside jaws to see if I can mill them down and put reversible tops on with cap screws to make up some inside jaws. Lots of good info on this BB!!

11-20-2002, 09:32 AM
Ah, success! Thanks to everybody, especially RR, who started me in the right direction. This Minnesota boy found a company in the far land of Nottinghamshire in the UK, by the name of Midland Tool Manufacturing Co. They have a website that has good drawings, with dimensions and prices. Of course the dimensions are in that "mm" stuff and the prices are in that "pound" stuff, but who said life would be easy? Once I get that all figured out, the UK probably will get a "yen" for the "euro" and I will have to start all over again anyway!

My chuck apparently is a Pratt Imperial, and they have soft jaws matching my dimensions exactly for £18 (currently $28.46). Knowing nothing about "soft jaws" before finding this BBS, I assume that I now go about shaping the jaws to suit my purpose, right?

I don't know anything more about the company or how good they are, but the web site is http://www.emnet.co.uk/mtm/ if anybody is interested.

Ragarsed Raglan
11-20-2002, 11:24 AM

Take my advice and get 2 sets (for the shipping price worth it!). I milled my set on the nose to give the narrowed land and get the small dia capability. Then mill the tops to give rough steps for the inside grip capability. Put them in the chuck ~ grip some bar and rough out the steps to something like concentricity. Finish off the internal, and external shapes with the jaws loaded in the correct directions. After this you can 'Kasenit' (but NOT the scroll thread), or leave soft to allow 'tickled' trueing at later dates. The second set (if you decide to buy them) can then be kept in stock for a rainy day!

I'll post some pictures of my jaws.


11-20-2002, 01:03 PM
Thanks, RR, but three questions: On the nose, how wide should the flat spot be, or is it just slightly rounded? You say to finish off the steps with the jaws loaded in the correct direction. Does this mean clamping a work piece in the jaws so they can be turned under work pressure to get a truer cut? Then you say to not harden the teeth. Won't they wear quickly on the scroll then? Or is it the brittle factor? Obviously I don't know a lot about hardening so maybe I should leave them soft...

Ragarsed Raglan
11-21-2002, 10:38 AM

Mill the nose of the jaws at 30* each side, so that when fitted together at 120* spacing they form a triangle in the centre. The width of the flats can be as you like but I would go for about 1/4" to 5/16" width. This later decision has also to be based on what is your minimum chucking diameter you expect to do; personally I don't chuck anything less than about a 3/8" diameter (if I want to turn something less than this, I use a collet chuck - 4C's for the Raglan)

There are lots of methods of pre-loading the soft jaws for finish machining. I have finish machined (by boring bar) the external gripping part of the jaws by turning a register to grip a 3 1/2" dia ring section on part of the jaw that will eventually be cut away to form the inner gripping steps. Another time I have used 3 bits of 3/8th gauge plate gripped between the flats on the nose of the jaws (those flats will be parallel to each other), at other times I have used dowel pins to grip a ring, the dowels drilled and let into the jaw tops.

When you come to finish machine the inside gripping steps you will have to load the jaws in an external expanding fashion; like gripping a small ring section with the smallest step diameter whilst you machine the outside and middle step, then you will need a larger ring (that 3 1/2" baby!) to be gripped by the middle step to finish concentric the small diameter step.

Just remember the jaws have to be gripping in the direction they would be used for the part you are machining.

You may want to keep the jaws soft, that way you can always 'true up' occasionally for those really accurate jobs (trued soft jaws will hold 0.0002" TIR ~ but will diminish accuracy with changed diameter, reloading, and wear). Or, then again, you may want a hard pair and a soft pair??? (I'm just trying to get the UK balance of payments looking healthy here!!) The scroll threads are best left soft, as you quite rightly suggested, to prevent embrittlement of the teeth.

An apology here as I was going to post a picture, but.... the web address I used for the rear toolpost shots (some 6 months ago!) I've forgotten ~ the ISP address, and my site name, and the password.....Dooooh! I'm now off to polish up my website building skills.

How do you guys post pictures that come up automatically on the thread? If it needs an external website ~ Neil, can we have a repository for pictures, scanned manuals, etc,? It need not have a long life time as a lot of these things are shortlived thread related issues. Howzabout it!


RR (edit note: repeating yourself is catching on this BBS ~ I never done that before, .....that before)

[This message has been edited by Ragarsed Raglan (edited 11-21-2002).]

Peter S
11-21-2002, 05:08 PM
S/M, RR etc.
Would it not be a good idea to get a hardened set of jaws? By all means get the soft jaws too, but I think that most of the time you will just use your standard hardened type?
Maybe they don't offer hardened jaws, in which case, ignore the above!

Ragarsed Raglan
11-21-2002, 05:18 PM

It's an economic decision here ~ £18 for the soft jaws or £120 for the hard version! Thats 5 sets of soft jaws and a night out down the pub, with a curry take away!

......Then again it could be 1 set of soft jaws and 5 nights down the pub, with a curry take aways to follow ......


[This message has been edited by Ragarsed Raglan (edited 11-21-2002).]

11-21-2002, 07:38 PM
Oh, jeez, now I got you guys fighting! Lets all go down to the pub and 'jaw' about it a little more. Maybe come back in about a week!
I think making the soft jaws fit sounds like a fun project, so that's probably what I will do.
Oh, by the way, did I mention that I need a 5-step motor pulley for my lathe too?....

11-22-2002, 12:15 AM
No you don't. Get a VFD instead and be happy, happy, joy, joy! Tell the better half they make excellent stocking stuffers... http://bbs.homeshopmachinist.net//biggrin.gif

Curry, eh? What's a matter - can't handle the HOT stuff? (titter, titter) http://bbs.homeshopmachinist.net//biggrin.gif