My preferred method for this kind of thing is to secure the panel to a
smooth flat board using double sided tape (not too much, and put most of it
under the "hole"). Use a tool with a radius arm at the end of which is a
small adjustable cutter (I think it's called a trepanning tool, they're not
dear). Put this in the pillar drill and set the speed to minimum. Take
care to control the cutting pressure when the cutter is near to reaching the
other side. I normally cut within 0.005" and then push it out and clean up
later.
If you use too much double sided tape, it's hard to remove the panel without
bending it. Hence the need to put the tape under the holes, then you don't
care.
Clamp the base board properly to the drill press table or you'll rip your
shirt if it grabs.
Dave Simpson
----- Original Message -----
From: <bizzarro@easynet.co.uk>
Subject: Re: Holes in panel
> Hi Richard
>
> We put our instruments in a removable aluminium panel that sat on the
> face of the original panel. We went to a local engineering shop with
> the centre points of each hole marked on the ali and he programmed the
> milling machine to cut the holes. It was perfect. If you can get the
> panel surface level and the panel in the milling machine, you could do
> the same.
>
>
> On the other side of the panel we found with our G meter, that the
> hole would be too small, so we centre popped the hole position and
> drew around with a compass the correct size, drilled out as much as we
> could with the hole saw and filed away the material with a half round
> file, and finished off with a flapper wheel. It takes ages but the
> results are good.
>
>
> Quoting Richard Holder <rholder@avnet.co.uk>:
>
> > I am about to do my panel.
> >
> > I understand that the main 6 instruments are best served by a hole
> > 3.16
> > inches, just larger than 3 1/8.
> >
> > Spruce have a 3 1/8 hole cutter which I'm sure will do the job.
> >
> > Everything in jolly old England is metric and hole cutters seem to
> come
> > only
> > in 79mm (too small) and 83mm (too large).
> >
> > Can someone who has done this give me some guidance ?
> >
> > Thanks
> >
> > Richard Holder
> > Kit 51 moving forward on its build after a 7 year wait (by someone
> > else).
> > G-OWWW.
> >
> >
> > The Europa List is supported by Aviators Network UK -
> info@avnet.co.uk
> >
>
>
> /////Eddie Hatcher Bill Lams Nick Crisp///////
> ///SouthEastLondonFlyingGroup/////////////////
> www.crispsite.flyer.co.uk/newropa.htm
>
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