Chuck choice

One thing to bear in mind is that PB chucks, - except the griptru, are now made by TOS.

-- Regards,

John Stevenson Nottingham, England.

Visit the new Model Engineering adverts page at:-

Is it just a case of badge engineering then?

Stu G

Depends on your point of view - I guess they would see it as outsourcing.

Regards, Tony

Probably not quite that simple. The chuck jaws seem to be almost but not quite interchangeable (between TOS & 'new' P-B). I don't have two of the same size to compare, but looking at an 8" P-B and a 10" TOS I'd say the P-B is heavier construction. Having used a 10" TOS and a 10" Bison on the same machine, I'd much prefer the Bison.

HTH Tim

Stu, I have examples of all the chucks you mention on my own Myford although my Toolmex is not the threaded body version, all of this type I have are Pratt Bernerd. All of the chucks work extremely well for me and have done for a few years now. I also have a couple of "unbranded" chucks from ArcEuroTrade and they are also fine. With one exception I wouldn't hesitate to spend my own money on any of those you mention. The exception is the "threaded body" design which unless exceptionally accurately made can cause a few problems with concentricity particularly if your spindle register is less than perfect. Given of course that normal 3 jaw self centering chucks are not perfect in this aspect by design anyway. The backplate mounted version at least allows you to correct small anomalies by machining the backplate register on your own machine.

When looking for smaller (4-5") new chucks I find that the TOS ones are a particularly good balance between quality and cost and I have bought several. My own personal preference, and I am at a loss to explain why, is for Toolmex (or Bison which I believe are the same thing). Unfortunately, I haven't been able to find any recently at a similar price to the TOS ones. The TOS ones I have bought because of their excellent price show good (but not perfect) concentricity and repeatability and have proven to be robust and reliable.

So to answer your question, there is a difference in my experience but it is not huge and is narrowing all the time; for my money it is not worth the significant price difference. If you need first class concentricity consider an ER25 or ER32 collet system which is now available at a reasonable price and get a TOS 3 jaw for the more normal work. You will get both for the price of a good quality "grip tru" chuck.

Best regards

Keith

Thanks for the replies everyone. I've decided on the TOS from Chronos as in the limited time I've had I can't find comparably priced backplate mounted Toolmex/Bisons and the comments on the PB 's aren't convincing me they are worth double the money.

I've got an ER32 collet chuck, backplate mounted, from ARC, but have only got one 8mm collet so far, so it's uses are fairly limited :) I've got some more on order now, but I can't justify buying a full set, so I'm bound to never have the ones I need!

Thanks again all,

Stu G

Stu, I wouldn't worry too much about not always having the right collet, I did it the other way and invested in a full set. My complaint would be that some of the collets are still unwrapped after more than two years whilst I have had to duplicate a few of the others, on the whole I think your way would have been wiser. I'm sure you will find the TOS chuck to be fine.

Best regards

Keith

On or around Wed, 04 Jul 2007 04:23:45 -0700, stooby-doo enlightened us thusly:

quite pleased with the toolmex I just got here, which is a 200mm. Slightly nerve-wracking turning the part-finished adaptor (cost over 100 quid) to final fit on the back of the chuck, but it came out OK. The chuck is the standard one and seems good so far, runs and grips true (not that I've put a dial gauge on it) but it's certainly not out when looked at while running, and experimenting with a bit of bar shows it's pretty close.

J&L were the supplier in this case - phoned 'em up to query various technical aspects and got a 10% off :-)

I was looking yesterday evening, G&M tools sell 100mm Toolmex's for =A385 +vat.

BTW there is a new P-B 6" 4 jaw going very cheap on the homeworkshop site at the moment.

Stu G.