& todays random 'wet behind the ears' questions are....

[HankMcSpank]

How do I measure how much backlash my homemade machine has (don't laugh!), so I can then enter a compensation in Mach? (as it goes - don't laugh - using delrin nuts on M8 there doesn't seem to be a huge amount!)

My Dremel is starting to get on my tits (too whiney & too feeble), so I was pondering has anyone used/seen/heard the Proxxon BFW 40/E

http://www.kdntool.com/_sgt/m5m4_1.htm

It seems to fit the bill (quietish - so they say), more power (rock 'n roll, rock ....rock 'n roll), a 1/4" collet holder (so I can start hanging out with the big lads).

The down side is that it only goes up to 5,000RPM......how much of a hinderance is that going to be (say for 'playing grown ups' & attempting to mill aluminium)...most of my cutting will be acrylic, so the lower speeds (vs the Dremel) should be handy.

Becuase I'm a bit of an electronics anorak, I'd also like eventually to be able to mill pcbs.... does the runout increase with router size? Am I likely to get runout 'for better', for worse until parts do me death?

Would 5,000RPM even do PCB milling well?

The ideal solution woud be to have two cutting spindles...the Proxxon for the chunkier jobs & something like the wolfgang for the PCB jobs....does anyone operate in this manner (ie a quick spindle changing option?)


Oh yeah...one last question, Two sided milling - how can I flip a part over to mill the other side, yet still have it lined up ok ...so that the tool ends up in the right place on the board vs the other (original) side - presumably some form of keying comes into play?