Where would you suggest buying them? A couple inexpensive ones would be fantastic for the first tests and inevitable crash. I was hoping to try 1/4 - 3/8 thick 6061 aluminum, which is a pain to tap manually. Might also try clear cast acrylic to see if the threads have a nicer surface finish than manually tapping.
Would like to do M6-1.0 threads, with a minor diameter ~5mm. So that .18 would fit nicely @4.6mm.
I saw a review on this one that mentioned some cutting parameters for successful threads in 6061 aluminum, however the RPM they used was 4500 instead of the CC router 18000 RPM.
“I tried this for some M6 threads in 6061 aluminum, using the 2D → Thread option in Fusion 360. Spin at 4500 rpm, feed at 320 mm/min, two step-overs with 0.15 mm step, 1mm thread pitch, 1mm thread diameter offset. Important: Choose “lead to center” in the linking options!”
So in theory I could replicate that SFM at 18000 rpm with around 4x the feed rate: 1280 mm/minute (~50 in/minute).
Would really appreciate a link to more economic thread mills. Saw some on Aliexpress for ~$14 but that takes well over a month to arrive.