Re: [CAD_CAM_EDM_DRO] Re: Leadscrews, PCB router experiment

http://cgi.ebay.com/aw-cgi/eBayISAPI.dll?ViewItem&item=1619357457


Here is a link to an ebay item for some of these drill bits. I bought
some a while back (1/6") and actually used them for router bits for
doing inlay on my cnc router. I have also cut thin stainless steel with
them, and use them to drill pilot holes. If you email this guy he will
probably sell you whatever size you need without going through
ebay.

usual disclaimer- I don't know this guy, just a customer

Bill

> Hi Jon,
>
> Carbide drills like these:
>
>

http://www.thinktink.com/cgi-bin/carbide.cgi?page=imperial&step=10&start=88

>
> It's the Think and tinker URL. They have a $50 minimum, so I'll need to
> get the ME bits too!
>
> I bought some surplus PCB drills at Haltek when they were still there.
> How do I know if they're carbide or not?
>
> Alan KM6VV
>
>
> Jon Elson wrote:
> >
> > Alan Marconett KM6VV wrote:
> >
> > > Hi Bob,
> > >
> > > I haven't done ANY yet! I bought an engraver 'V' bit, and I'm hoping

to

> > > use that. I like the idea of using a starter hole; that would be
> > > "spotted" with the 'V' bit? I would be drilling the holes with the

same

> > > setup, not as a separate operation (just change the bits).
> >
> > I use solid carbide drill bits specifically made for PCB drilling. They
> > really
> > don't like anthing that tries to make them bend. So, there is some risk
> > in putting centering holes in the copper. The carbide drills really

won't

> > follow them anyway, bit it could cause the drill to bend slightly as it

goes

> > through the copper, and then put more side stress on the drill bit as it
> > continues through the material. If your machine is highly repeatable,
> > then this won't matter. But, the solid cabide drills will drill the

hole

> > right
> > where the spindle is, so you don't NEED a centering hole.
> >
> > The HSS drill bits are awful, and you are lucky to get 100 holes per bit
> > with them.
> >
> > Jon