Using A Er32 Or Er40 In A Bridgeport Mill R8 Collet

Really good discussion & information here! I posed a similar question link below just for good measure. Consistent theme.
http://www.hobby-machinist.com/threads/er32-vs-dedicated-endmil-holders.54052/#post-448661

Re the size issue, I bought an ER40 setup years ago when I was getting started (read naivety). And then I added onto that tooling with 4-side & 6-side collet blocks which are really nice way to hold round things in a mill vise at different orientations. Much more compact & functional over the 5C equivalent IMO. But if I had to do this again with a clean sheet of paper, I would go for a smaller kit, like ER32, maybe even ER25 depending on how you see yourself using it.
- lower tightening torque as mentioned
- smaller nut diameter (which can sometimes be a proximity or interference issue on small end mills depending on the job)
- less expensive
- same collet blocks can be acquired, also slightly less expensive

Regular EM holders still have their place. I wanted to try a Lyndex brand (which I really like) so bought a second 1/2" socket (R8) just to try. Now what I have is a 1/2" rougher EM in one holder & a 1/2" finisher in the other. I can swap them out of the mill pretty fast & all my DRO settings are preserved since EM same diameter (+/- teir tolerance). This has been my mainstay milling setup for many parts unless different sizes are required.
 
MonkMan, have you considered making your own fixture? If your ER chuck has flats or hex on the body itself then you can make a female fixture from aluminum that is a good fit and bolt the fixture to the bench. As long as you have working room to manipulate the nut then it should work fine.
That sounds like a plan! The chuck is on its way so I'll check to see if that's a workable solution.
Thanks so much, Paul
 
That sounds like a plan! The chuck is on its way so I'll check to see if that's a workable solution.
Thanks so much, Paul

This is one of the things on my To Do list for my ER-40 chuck that you probably will beat me to. I was going to make mine in two pieces - one to support the chuck body to hold it level and the second to slip the flats of the chuck into. The second will probably be 3/8" aluminum plate that is screwed to the first piece that will be from some relatively soft stuff like aluminum. The first part will be screwed to a piece of plywood so I can move it into a usable position when needed and stored when I don't need it. If you build it, do a write up on it and post it on the forum; I'm sure others will follow your lead.
 
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