Charles Vincent wrote in
:

Fortunat1 wrote:

Thanks, this is exactly what I discovered. It's good to know I'm
going down the correct path.

You are drilling the cleanest hole, but still may not be going down
the right path. The report I quoted was written before the invention
of modern epoxies. I think that coating oversize holes in the wood
with epoxy will give you a stronger structure by further reducing the
bearing stress on the wood, but that is just my opinion.



You're probably right, but the way I see it is that airplanes just like
this have been flying wth their original spars since the flood, so if it
was ood enough for them it's god enough for me. Also, this is a plank
spar, not a capped spar, so there iis plenty of meat there. I'll
certainly keep the epoxy thing in mind in case I screw up some of the
holes when drilling them out for fittings, though. Nice to know there is
a fix for any mistakes.

Yes, pucker is a better word for it. the drills are nice and sharp and
I'm getting a good cut there. I've been cutting them out to 7.7 mm and
then reaming to 5/16th. You're right, some of the holes are cut pretty
clean, but the reamer soon produces the rounded pucker as you so aptl
put it.

If it is poor practice to leave the ridge on the edge, what's the
best method for getting rid of it? Aside from a special machien, I
thought of carefully cutting it down with a large dril bit, but I'd
be afraid of doing some damage to the part.
Any suggestions?

I personally would not be comfortable leaving the ridge, particularly
since I do not know what it looks like. If it is an ordinary burr, I
would use a deburring tool.


OK, it's not a burr, it's more the pucker you describe. does this mean
the part is trash, or can I leave it or should i try a deburring tool on
it? The reamers are new and seem nice and sharp, I am getting swarf, but
not as much maybe as you would expect..