threaded end mills?

[isaac338]

I'm looking at buying a lot of tooling from a guy while I'm here in England for a week - it's dirt cheap and the measuring tools alone make it worth the price. The photos he sent me of the lot show a lot of reamers and end mills that are threaded on the end. What kind of mills are these? All mine are just plain shanked and I hold them in my mill with a collet. Assuming I can get a collet that'll hold the shanks on these, will the threads interfere?

He also has a bunch of twist drills and reamers that are in the lot but the reamers look to be a morse taper with a tang on them. They might be useless to me until I get a lathe..

Thanks for your help.

[HuFlungDung]

Threaded shank endmills are designed for use in Dormer or Clarkson autolock milling chucks. These chucks have special collets with threads to screw the cutter into, then the whole assembly gets clamped in the special chuck built for accepting these collets.

Dormer collets and Clarkson collets (and chucks) are not interchangeable, AFAIK, and I've got both, but they are 30 years old too

Threaded shank tools may have a slightly lower spec on the shank diameter and may be a bit loose in a set screw side lock holder. But, I have seen some of these tools manufactured with a weldon notch, so I suppose maybe those ones are closer to spec.

My advice: get the chucks and collets that match these tools if possible.

Oh: the advantage is that the tools are very secure in position once properly loaded into the chuck. The general method is to start the tool into the threaded collet, then assemble the collet into the chuck, bringing the nut up finger tight (or just a wee bit less) so that you can then screw the tool in (with a rag around the tool) til it bottoms. Then take the chuck wrench and give the nut the final cinching. This closes the collet and locks it into the chuck at one go.

I have seen some guys have difficulty using these chucks because they did not grasp the concept of how to load them.

[isaac338]

The ones I can see in the picture definitely have the weldon notch in them. I'm thinking that even if I can't use the mills the lot is still worth it, and I might be able to use them with some metric collets.

The lot includes a couple engineers' squares, and two dial indicators, a Federal and a Mercer, which are worth about $400 combined according to google.

Can you find any places online to buy the appropriate collets for these mills?

Thanks!

[HuFlungDung]

Here is a starter:

http://www.clarkson-osborn.com/clarkson/index2.html

Note that the threaded collets won't do you any good without the chuck that they fit. If you want to use collets for just general purpose machining, just get some ER collet chucks.

[isaac338]

Hey zeus, a chuck kit for R8 with 4 collets is $750. Hopefully these'll work with normal collets or this doesn't seem worth it..

[mactec54]

Hi isaac338

You can use these end mills with the threaded end in regular collets the diameter are the
same as a normal end mill I use them all the time I used to have a clarkson autolock chuck they work great but are not needed you will find most of these cutters will be metric coming from England unless they are very old cutters & then they could be inch dia

The threads will not interfere with the regular collet as the thread is just below the shank size or somtimes the same size as the shank but never bigger than the shank

[littlerob]

How current does the tooling look? Iscar makes an interchangeble endmill IE. it is an "arbor" that you can put a ball mill, or a keyseat cutter, or rough mill, etc. It is threaded with I think, a standard pipe thread. But I think it is pretty new, (could be wrong). I use one with the keyseat cutter and love it. Robert

[marsmach]

Hi Issac338
You will have no trouble holding these cutters within any make of collet,as said in a previous post thread slightly less than nominal cutter shank,Use them all the time in DA collets...

[isaac338]

I bought the load today. Two engineer's squares made by Moore & Wright in Sheffield, two indicators (a Mercer and a Federal), a cheapo huge dial caliper, three micrometers (probably Asian), and a huge load of Clarkson and Osborn end mills (about 30), 10-20 osborn spiral taps, some lathe tools that take inserts, some hand-ground lathe tooling, some lathe tool blanks, and 5 or 6 T+J reamers of various sizes made in England.

Pretty good haul for fifty pounds (about $100CAD), I think...

edit: I just realized Merlin and Blue Wizard are also made by Clarkson - there's a bunch of merlin/blue wizard taps and end mills. What a score!

edit 2: Of the three mics which I previously thought were cheap Asian stuff - one's a Mitutoyo 0-25mm, one's a Kennedy 25-50mm, and one's a Moore & Wright 0-25mm. Holy crap!

[HuFlungDung]

You did real well at that price. You can throw all the endmills away and still do well

[littlerob]

Just being a smart ass. Japan is in Asia. But it sounds like you made out pretty good. Robert

[isaac338]

Just being a smart ass. Japan is in Asia. But it sounds like you made out pretty good. Robert

shut up, you. i thought about that after i posted but i was too lazy to edit. haha