Mini Mill. Collet Tooling.......

[Stilldrillin]

Hi Chaps.
My online pal is hoping to set up a new mini mill, shortly.

MT3 quill. My initial thoughts were for ER25 collets. Buying inserts, as/ when needed.

Will these do the same job, cheaper?   http://rdgtools.co.uk/acatalog/copy_of_3_MORSE_TAPER_COLLETS.html

I'm concerned about MT3 holding/ releasing milling cutters.

David D

[BaronJ]

Hi David,

My mill is 3MT and I have a couple of these collets.  I don't have any problems with them at all.  I do admit that I bought a collet chuck and a set of collets for mine which I find more convenient, and overall somewhat cheaper.  The main advantage to using MT collets is that you gain about 2.5" inches in terms of tool to work hight.

 

[spuddevans]

While the MT3 collets will buy you a valuable 2.5" extra working Z-Height, you will soon get sick of pounding the life out of your drawbar/bearings when releasing to change cutters/drills/ect. If you had a R8 spindle (self-releasing taper) I would say go with the R8 collets to get the extra headroom.

I have a ER32 collet set which is shared with my mini mill and mini lathe, and it is very convenient on both machines. I rarely take the ER chuck out of the mill, and the clamping range of the ER collets is great (1mm as I recall, although the smaller sizes (2mm and less) dont really close that much, I hope to get a 1.5mm and a 2.5mm collet to complete my set)


Just my 2p, worth exactly what you paid for it 

Tim

[Stilldrillin]

Baron, Tim.
Thanks for your thoughts. 

Common sense says ER collets. Tool gripped in collet. Shank held sensibly, in the quill.

I think MT collets will need too much drawbar pressure, for happy releasings.


My first mini mill was MT3. I learned to sensibly , clunk the shank into the quill. Using the drawbar to retain, "finger" tight, only.
The ER32 was a little oversize, I thought. It was occasionally used in the mini lathe.

My second Chester Conquest was modded to R8, during commissioning.

David D