Never seen an adapter the way you want it, fizzy. Local supplier here lists them the other way around (R8 into spindle adapting to MT3 tooling) but not your way.

I think it would be possible to remachine the spindle to R8 which to my mind would be the best solution, it would be critical to get it right first time though.

Mike

There is no such fitting,not that I know of anyway. Be happy with your mill as it is.

Fizzy, you didn't say what mill model it is. Is it possible that you can get an upgrade kit to convert the mill itself to R8?

When I got my WM16 lookalike here in Canada it came only with an MT2 spindle. Later the seller decided that there would be more demand for MT3 and subsequent machines had that. To satisfy existing users they sold some upgrade kits to convert the machine from MT2 to MT3.

What they didn't publicise, but what I discovered by talking to my friendly salesman, is that they also bought in a few kits to convert the machine to R8. I snapped up one of those.

The kits consisted of a complete new spindle assembly and was simple to fit.

It might be worth asking the question.

I don't agree (that he has wasted his money). While what you say is true about the 1mm range, using the bottom end of the range is a nuisance at best. And some imperial sizes fitted to metric collets are right at the bottom end of the range forcing you to do a three-handed act tightening (and tightening and tightening) the collet while trying to keep the cutter (or whatever) in position. Likewise when you release the cutter it will drop from the collet the moment you slacken the nut.

I started with an ER32 metric set years ago but rapidly built up a range of imperial collets to improve the range.

You could argue that it's not necessary to buy a full set of the second-system collets – just those needed in the worst cases but but I don't think the full set is wasted. (Especially if you have more than one machine using the same collets e.g. lathe and mill).

Edited By Bandersnatch on 14/07/2017 15:09:00

I'm surprised that no supplier offers a limited set of ER collets comprising only standard milling cutter shank sizes for pure milling machine use. Cost savings should be appreciated by typically impecunious Model Engineering / Home Workshop types. It would be no great problem to offer expansion sets to cover the full range of native imperial or metric sizes should the purchaser eventually decide to use them on the lathe as well.

I prefer the Clarkson style treaded shank cutters for un the appropriate chuck milling in my Bridgeport. I do have an ER32 set on an R8 taper, purchased following magazine advice when I got an R8 square column mill. Almost unused since I rapidly bought the Clarkson set-up following practical advice from an experienced person. Along the way I picked up native R8 collets making the ER system redundant. No use to me on the lathe as mine has a native 5C spindle. A full set of x 1/64 th imperial and half set of x 1 mm 5C covers all my needs.

Never been that impressed from an engineering viewpoint by the ER system due to the monster tightening torque needed to ensure accurate results. The can hold accurately at lower torques, especially when used with minimal compression on material whose nominal size matches that specified on the collet, but if you want specified accuracy everywhere in the range book torque figures must be followed. You won't do that with the tiddly sheet steel spanner in the set.

Clive.

Does a morse taper milling spindle have a slot to eject tanged tooling? I have an R8 spindle and if I use a morse adaptor for tang tooling I need to remove the adaptor and the use the normal taper drift to eject the drill or reamer from the adaptor, OK for the odd job but it would drive me nuts if I needed to do many tool changes.

Mike

Thanks Thor, that is interesting. I don't use my mill with tang tooling except for some larger MT3 drills in the mentioned adaptor. If I use my mill for drilling I use an ER chuck and jobber drills, most simple drilling I do in my pillar drill.

Mike