I’ve got a project where I need to drill 64 holes in 3/8" thick acrylic for slotted spring pins. I looked and looked but couldn’t find a 3/32" drill bit with a 1/8" or 1/4" shank to slip into my router. That got me thinking about Dremel keyless chucks. I have several of them. I wonder if one could be modified to be put on something with a 1/4" shank. I’ve seen similar things all over ebay. I know those are meant for high rpms but I’m able to slow my router down to 5k and that is where I have been doing all of my 1/8" and 1/4" drilling in the past.
Anyway, I’ve got to have something today so I made a quick-n-dirty adapter. The runout is about .003" which should be fine for my project. See attached image. It only took me about 20 minutes to make. Still, it’s a shame someone doesn’t make a high speed precision chuck for small stubby drilling.
Can’t speak to the longevity of these, but I have used them several times for projects (cutting acrylic and engraving aluminum) that needed fine details:
I’m going to once again recommend drillman1 on ebay. I am about 90% sure I have these drill bits at home, so I can throw a piece of cell cast acrylic on my XXL and punch some holes to check if they work.
Here are some 3/32" carbide PCB drill bits that will just clear the 3/8" thickness (they have a 0.400" flute length).
I would also not hesitate to do peck drilling with an end mill either, but that’s just me. If you’re up for that, there are a lot of options as well, just avoid any down cut bits.
Those are perfect! I just ordered a set. I’ll look over drillman1 to see if I can get other sizes. Don’t need them now but might be handy to have for future projects. Big thanks!
Wasn’t satisfied with the drill bit adapter I made so I made a new one. Bigger collar to sink the fasteners inward. Cut a prototype out of 1/2" thick acrylic. Very satisfied with the results.
