It has just occurred to me that in my post on cutting thin walled
tube I didn’t mention the type of saw I use for cutting straight lines
in sterling 0.5 to 1.0 mm sheet. (But no good for tube) In a good
hobby shop; the sort of shop which caters for young model aeroplane,
car and boat hobbyists, you find they sell little saws seemingly for
use in cutting balsa, etc. The hobbyists call them razor saws. They
are very cheap - oh about US$ 2.50 or so, though you may have to buy a
little tool type handle for them (I make my own) They are much like a
little carpenter’s tenon saw (back saw), but made of very thin steel
and have a back like a tenon saw. The teeth are very fine; 30 per inch
or thereabouts. Coat your piece of thin metal sheet with marker pen
colour and scribe your straight cutting line with a heavy needle
mounted in a short length of wooden dowel. I clamp the metal firmly
to my bench peg with a non scratch clamp, place my thumb nail near
the line and use it as a guide to place the saw on or beside the line.
Keep the saw at a very shallow angle; just a few degrees, and make
the first marker stroke by drawing the saw backwards. Now saw with the
blade lubricated with candle wax, and use long, slow strokes, making
sure to keep the angle very low, and not too much pressure. If you
are careful and after a little practice (with copper) you’ll find you
cut a perfectly straight line. If your saw keeps jamming, it means
your angle isn’t low enough. Looks impossible to cut a 6" line with
such a saw, (the blade is only about an inch from the back) but
believe me, it gives a quick straight cut. What reminded me is that
I just a moment ago had to cut a 4mm x 25mm x 0.5mm strip of sterling
seconds or so, and of course leaves a straight edge on the stock to
cut other strips. And that’s enough cutting remarks from me, don’t you
think? Cheers, – John Burgess; @John_Burgess2 of Mapua Nelson
NZ