[Amps] Building an Amp 101

[peter chadwick]

Jerry,

You do need some tools. An engineers square with ruler, a scriber, a centre punch and a hammer, drills - and don't get cheap ones, Sears used to and maybe still do some good German ones -  a few good new files of various types (flat, warding, half round, rat-tail and triangular), a hand drill or maybe big and little ones, and big and little hacksaws and a vice - about a 4 inch. Plus some bits of angle iron about 3/4 by 3/4 or 1 by 1 inches and 1/8 inch thick, and a couple of small carpenters G clamps. A few odd bits of wood come in handy, too - short (2 to 3 inch) lengths of 2 by 1. For expendable material, you want emery cloth. A small wire brush (barbeque cleaning type) is good for keeping the files clean.

With flat files, you want something like a 10inch bastard cut with a safe edge and a smaller 6 inch 2nd cut. The half round and rat tail can be second cut.

With that lot, you can cut aluminium sheet to size (score a line as deep as you can on both sides, clamp it between the angle irons held in the vice  with ends of the irons G cramped together, and then bend back and forth until breaks. Clean up by putting emery cloth flat on the bench and run the sheet edge along until it's clean. Or don't score quite so deep, and you can bend it, using the hammer and block of wood to square up corners.

With sheet aluminium and 1/4 by 1/4 by 1/16 aluminium angle stock, you can make good enclosures: a cheap pop riveter can ease matters.

A $40 set of taps and dies from Sear were a good buy for me - from 6-32 up to 1/2 inch in fine and coarse thread for the sizes above 1/4 inch.

Those are the techniques I used before I got my fairly well equipped workshop with lathe, mill, shear, metal brake, drill press etc...

It's worthwhile getting some of the books available on model engineering techniques if you have never done a workshop techniques course. 

'Model Engineering, a foundation course' by Peter Wright, published by Nexus Special Interests 1997, ISBN 1-85486-152-2 is good.

The older (1960s) ARRL handbooks have a lot of good advice on workshop techniques, too, under the chapter 'Construction Practises'.

Good luck

73

Peter G3RZP