Re: [CAD_CAM_EDM_DRO] Small, hollow, thick-walled tubing needed

Oooh...that's going to be hard to find!

I haven't looked in the catalog but you might be able to buy some extra long
drill bits that have coolant passages down the center. Just cut off the
drill portion and machine to fit. The drills are made of pretty good steel
and would be ideal for the purpose if you can find suitable ones. They'd
be a little expensive for the job though.

Another solution would be to forge your own. Build a spilt die, use larger
size tubing, run a hard wire down the center after heating and squish the
die around the wire. QUICKLY!

Smoke

> I need 3/16ths od with a thick enough wall to do an external thread
> at each end, yet hollow enough to allow oil to drip through. These
> are to be used on my little Merlin engine project, and I'll need 28
> pieces about 3.5 inches long, 3/16 od, with some sort of oil passage.
> The hole is to allow oil from the camshaft area to drip back down
> into the crankcase. Yet these are actually hold-down studs for the
> cylinder block (including cyl. head) so they have to be strong enough
> to be torqued. The engine is 1/4 scale.
>
> Any thoughts on where I might easily buy such tubing? I have checked
> the hobby shops, and it's a good start, but the hole is a tad big for
> me, so the walls are not quite as thick as I'd like.
>
> Thanks in advance. Tom Kay.
>