"Jim Wilkins" wrote in message
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"Bob La Londe" wrote in message
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"Bob La Londe" wrote in message
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"Jim Wilkins" wrote in message
Can you attach a guide to the mold?
Well the idea was I would make a guide that sits around the protrusion
snugly, and has a long hole through the center to run my bit extension
through. I suppose I could make another precision surface and attach
the guide "outside" of the mold, but the inside where it rests is a
finished surface already except for needing to drill that one hole.
I'll draw up a quick example.
http://www.yumabassman.com/images/CROSS%20SECTION.jpg
I have made bushing for odd size end mills. I figure the extension is
just a really long bushing. The hard part is making a guide for the
extension.
Looks like you tilt the base of the mold and drill squarely into the
angled face of the boss. I'd consider a drill guide in the end of flat bar
stock with a recess, pins, whatever to locate it on the boss, and the
other end of the bar solidly clamped to a stack of 1-2-3 blocks etc for
the height and to restrain the lateral forces on the locating components.
Then you could use the aircraft drill.
jsw
Sorry, Guess I wasn't clear. I have aircraft drills, but I do not have a
..090" aircraft drill. I have a .090" ball end mill though. Hence making an
extra long 1/8 end mill bushing (AKA) drill extension to hold the .090" ball
end mill. I was thinking of using the aircraft drill to make a guide for
the bushing. The problem is that I have never been able to drill more than
an inch or two with a .250" aircraft drill without having flex and off
center drilling. I would need to be able to drill 6 plus inches down the
center of a piece of rod to make a guide for this.
The hole in the protrusion needs to be pretty close to .090". .125 (My
closest aircraft drill) is not close to .090" for this application. .095"
would be considered close.
I have found I can't really drill with a ball mill, but I can peck drill
with one if I have to...
By appropriate size aircraft drills I meant smaller than the clearance
numbers and longer than the necessary reach.
I guess its time to break out a piece of brass rod, make a bushing, and
see...