Milling cutters

I have some of these milling cutters with a screw thread as a mounting point. So my question is this type still used and if so are there any mounting adaptors still available or have they now gone over to the straight shaft type I have seen around.

Yes they are used. They can be mounted in an ER collet as well. You will have to rely on someonelse to tell you if the Clarkson type holders are still available as new items. Plenty available second hand and I expect collets are available from suppliers.

An alternative is you looking on the internet for yourself.

Clarkson holders required, as mentioned can be held in ER collets, I have a mixed bunch of cutters including this type, I use my ER 25 collet to hold ea. type & have had no problems so far.

George.

Thank you at least I now know the name of the holder and it was not just the name of the bit. So I can now search away

Most of the usual ME machine and tooling suppliers will have holders to suit so you don't just have to search for old Clarkson branded ones. Myself I just hold them in my ER Collet holder.

Vertex do an Osborn clone version using the same Clarkson thread. There are 4 sizes of collet up to 5/8" or 16mm

The reason for the threaded cutters - Clarkson style - is to prevent the cutter being pulled down form the collet when side cutting or when a deeper cut is applied.

On smaller machine's this is less of a problem but it can still happen particularly if you are using a longer length of the cutter flutes. For most model engineering where smaller cuts and smaller cutters are being used ER collets work very well.

However even on small machines it can and will happen if cutting with larger cutters say 5/8; 3/4" and a fairly deep cut is applied its very possible for the forces to pull the cutter down from an ER collet, this cannot happen with a screw shank Clarkson cutter in a Clarkson chuck.

So just be aware of the limitations of ER collets if you need to remove a fair amount of stock, more smaller cuts are the order f the day -- don't be greedy and try one large cut !

John

Hi Derek,

If you want a new chuck for your milling cutters, you could try the Posilock from Chronos. I just do as the others, use my ER chuck.

Thor

I did get these for another application and as of yet need to buy a milling machine. it was just a question for the future reference. but at least now I know the name of the type of chuck to look for.

I will have so many questions as I go along. I really need a much larger workshop to accommodate the machines I already have as well as those that I want in the future. Any Questions that I ask are in preparation for that time

Hi Derek,

Is it my imagination or do they have a shallow taper as well as a fast taper?

If so, they are probably intended for milling draft on patterns or moulds.

Neil

Derek,

You may find this previous thread of interest: **LINK**

https://www.model-engineer.co.uk/forums/postings.asp?th=105995

MichaelG.

I meant to have a look but twice I forgot and locked up the workshop. I will have a look tomorrow if I can remember