Archive of the former Yahoo!Groups mailing list: Homebrew PCBs

hi!


I want now to buy some carbide drill bits now at ebay.
there is a guy selling used, but sharp, bits. (all customers are very
satisfied without regrinding them)

i will have to order them soon because he also offers carbide mill blades
now, this blades look like a circular saw
blade but have a slightly bigger center hole (22mm). the outer diameter is
55mm.
they are made of carbide steel and i think they would be suitable as
circular saw blade.
the carbide blade from proxxon costs eur30, these blades are much cheaper.
sure, i will have to make some kind of adaptor to mount them on a 10mm
spindle but i think i can do this.


but to the drills:
he sells 100drills for ~eur 20.

so i can take some...


but which diameters should i choose?
until now i used hss drills, because my drilling motors would break the
carbide (especially at freehand use).

i never drilled 0.6mm, does it make sense to buy them? are many component
legs suited for this?
do they break too easily or can i work with them (good motor and pivoting
press)?


i will of course buy some 0.8mm and few 1mm too.

so what do you suggest, which drills use you most?
which diameters can you recommend to buy and in which number?

he has all standard diameters i think and (and also the ones not so
standard) so it's hard to choose.


thanks for any suggestions.



//////

drill press possible viewing apparatus:
i found a old (russian?) microscope here. it has 2 lenses on a revolver, x8
and x20.
i think this would be fine for a drill viewing device.
if i mount the whole revolver i might use also the x20 lens for other
inspections.

have you any ideas how to illuminate the pcb then?
i guess when using a camera it needn't be too bright but if trying
projection it has to be damn bright?


regards
stefan