Questions about using 1/16" and smaller Collets ER20. Will not install in Collet nut

[Whambam]

I own a desktop max. I drill LOTS of small holes with my CNC, so I purchased small collets for my tiny bits.
I just purchased a 1/16 er20 Techniks collet. Unfortunately the collet won't compress enough for me to install in my collet nut.
Is anyone here super knowledgeable on collets? Very difficult to find info on it.
Thanks!

[Rob Gunn]

I made a number of collet adaptor over the years. Basically its just a length of roundstock with the outer diameter a larger normal size than your bit size. For your 1/16 bit size I would probably try a 1/4 O.D. then drill your 1/16 I.D. then you have to slot the adaptor so it will compress. Of coarse you will need a lathe to drill the hole on center. Or if you have a friend that's a Toolmaker then he could do it. Or Google "Collet Adaptor" and you will see a number of images that will show what is available and what can be done.

[Dish]

Rob I think what you are talking about is a reducing collet adapter.

[Whambam]

Thank you Rob. Definitely a very good suggestion. I have made a collet adapter that way in the past, however I use so many different sized 'mini' drill bits I was hoping to just be able to purchase the collets as I needed them. Especially for me since I have a wood lathe, and no machinist friends.
For anyone having this same issue, I called Techniks and they shipped me their standard collet nut and it works perfect with the tiny collets. For some reason the collet nut that came with my Desktop Max will NOT fit smaller collets. Just got the collet nut from Techniks in the mail and it fits all my collets PERFECTLY. Not sure why the original collet nut did not fit the smaller er20 collets, but this new one is great.

[Brady Watson]

Most ER collets have the ability to contract about 1mm under the specified size. However, most of the collet nuts you are going to find on 5hp and under spindles, don't have enough threads on the collet nut to fully collapse the collet at the lower bounds and you can bottom out the threads on the nut...and subsequently HAVE TO cut the nut off with a whizzer wheel because it won't budge even with a 4' cheater bar. Been there...as have others. Lesson learned.

Haas has some really helpful videos on YT. This one goes over ER collets. Have a look, specifically around the 6:30 mark.

FYI - SB did send a few DT series tools out the door with dual Z axes on them. If drilling a lot of holes, you might consider a corded drill on one Z and spindle on the other. There's nothing better than an actual drill for drilling, with the proper RPM and convenience of a chuck.