On Mon, 08 Jun 2015 08:52:07 +0800, just_me wrote:

On 08-Jun-15 5:32 AM, Tim Wescott wrote:
On Sun, 07 Jun 2015 18:25:11 +0700, John B. wrote:

On Sun, 07 Jun 2015 01:42:48 -0500, Tim Wescott
wrote:

On Fri, 05 Jun 2015 17:04:29 -0500, Tim Wescott wrote:

I'm looking for product names to look for.

I'm working on an instrument for a customer, and he's having me do
the whole-system design. This means I'm out of my comfort zone and
playing with mechanical issues.

It needs a big outer case (well, four feet long, by nine inches by
two).
I'm thinking of doing the outer case from fiberglass for a number of
reasons, not least of which because I'm familiar with its
characteristics, and the instrument is going to be used on or near
bodies of water including salt water.

I'll need to attach things to this outer case. My current thinking
is to used buried studs and/or nuts, and use thumb-nuts and
thumb-screws to actually attach the bits. I'm assuming I want to
use brass or stainless hardware for corrosion resistance, and I
probably want to take some pains to match alloys.

McMaster is failing me for appropriate hardware. I'm finding
thumbscrews and thumb-nuts, but I'm not coming up with good
candidates for nuts that I can bury in the fiberglass. I'm assuming
that the case will be a two- part assembly that's glued together;
nuts that can be buried in one side and then captured in the
gluing-up process seem to be the best notion to me, but if someone
with actual experience has alternate suggestions, I'll listen (I may
not _take_ your suggestion, but I'll certainly _listen_ and _think_
about it).

So -- suggestions? I'm probably wanting some 4-40 or 6-32-ish sized
ones, and some 10-24 (or 1/4-20). The bigger ones may work better
as studs, with thumb nuts. I'm pretty sure that I want nuts for the
little ones, unless that presents severe difficulties.

Your responses made it clear that I left out an important part: the
case will be made with two or three fiberglass bits, glued together
and finished. I'm envisioning the fasteners going into the top
piece, then getting captured by the bottom piece, or perhaps some
inner third piece.

The usual scheme with molded fiberglass is to (hopefully) build a mold
that does everything in one fell swoop. Failing that, two parts that
fit together as they come out of the mold. Cutting and trimming little
bitty pieces and gluing them in and maybe coming back the next day to
laminate a little cloth over them to make them stronger is a time
consuming process and results in "things" that aren't all the same and
bits that fit "Thing #1" probably won't fit in "Thing #2".

Thank you very much for your expertise. My family has been making car
parts out of fiberglass since 1957, so we may actually have some clue
of how the stuff works.



A bit snarky Tim?

Yes. Apologies tendered to John.



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www.wescottdesign.com