Pratt Burnerd Multisize Collets

Does anyone here know the differance between EC type collets and the MC style?

Which is the newer design?

I am looking through the crawford collets web site but havent found an explination yet.

Regards

Steve Larner

Reply to
Steve Larner
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Steve, I have the full Crawford book in front of me but I can't find any reference to EC. MC is listed as Crawford collet number T-980 On the Multibore page T-980 then lists as 1/16" to 3/16" as B1 in round and then 1/8" to 14" as B2 and so on in increments of 1/8" up to B9 at 1" to 1

1/8" Hex has the number B69 to B75 up to 1" Square has B86 to B91 up to 3/4"

-- Regards,

John Stevenson Nottingham, England.

Reply to
John Stevenson

Thanks for the info.

I bought a unused colletchuck from RDG then various EC collets of e-bay and at exhibitions only to find that the EC dont fit and that there was a 35mm collet of the MC type inside.

The MC type dont have the fingers protruding through the locating ring like the EC. Looks like i will have to hunt out MC collets as they are current.

Thanks

Steve Larner

Reply to
Steve Larner

Thanks for the info.

I bought a unused colletchuck from RDG then various EC collets of e-bay and at exhibitions only to find that the EC dont fit and that there was a 35mm collet of the MC type inside.

The MC type dont have the fingers protruding through the locating ring like the EC. Looks like i will have to hunt out MC collets as they are current.

Thanks

Steve Larner

Reply to
Steve Larner

Thanks for the info.

I bought a unused colletchuck from RDG then various EC collets of e-bay and at exhibitions only to find that the EC dont fit and that there was a 35mm collet of the MC type inside.

The MC type dont have the fingers protruding through the locating ring like the EC. Looks like i will have to hunt out MC collets as they are current.

Thanks

Steve Larner

Reply to
Steve Larner

EC is a Pratt Burnerd collet and MC is a Crawford collet.The Burnerd is known as Multisize and the Crawford as Multibore.The two are not interchangeable within the same chuck,although on some collet chucks you can change the closing sleeve to allow you to use other collets but they are still not interchangeable. Kind regards,Mark.

Reply to
Mark McGrath

Just to make things more confusingI have two collets of the same Bore one Ec and one MC.

The EC one is marked BURNERD MULTISIZE. Fingers visable from front.

The MC one is marked BURNERD MULTISIZE. fingers covered by Front locating ring with 8 csk screws in.

Regards

Steve Larner

Reply to
Steve Larner

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