wrote in message
...
On Sat, 10 Nov 2012 15:48:50 -0600, "Paul K. Dickman"

[...]

Have you considered adhesives? No heat required and with the right
adhesive it will be at least as strong as soldering.

I have used some adhesives on metal to metal that impressed the hell out
me,
but this would be a bad application. In the end the sheet gets slit up
into
eight 1"wide x 6" long fingers that flip up and rest on the hinge just
past
a 90 deg swing. That would put 5 1/2" of leverage on a 1/2" wide glue
joint.
I think that is asking for a peel failure.


That applies to soft solder also. As the previous poster mentioned the
modern adhesives have strengths comparable to soft solder. The limited
research I did into this some time ago bore this out and I stopped
using soft solder for most applications I did previously.

Michael Koblic,
Campbell River, BC

Sorry, I didn't get back.

Hard drive problems bumped me off line for a while.



I am very familiar with high tech adhesives and as I said before they won't
work for this application.

Peel strength is their biggest shortfall. The best of them are rated to
25-40 lbs per linear, inch, a decent solder joint is 10 times that. You can
design around this, but that wasn't an option here.

I have a 1"wide joint at the end of a 6" finger with the top of the joint
and peak point of pressure 1/2" from the end. That is 11-1 leverage. With
glue I could expect that to withstand 2-4 lbs of pressure at the tip before
it fails.



I built the soldering gizmo and it works pretty well, but I have to
superheat the copper with a propane torch. I may be able to avoid this step
with some insulation or perhaps a second strip heater.



It aligns the pieces easily, solders them fully without cooking the lacquer,
and minimizes handling of the polished sheet. And I was able to avoid
tinning the sheet.



I am pleased.



Thanks to everyone.

Paul K. Dickman