Hmmmmmmm - - - - where does one find a 'very large supply of free scrap material' ?
I, for one, would love to know - - - - pretty please!!
I work at a university, and have been granted access to the scrap metal bin. I should hasten to say that it is not at all like there is material of every size and description at any given time; quite the contrary. Some days there is nothing of interest - maybe some flimsy window screen frames or rusty and crusty pipe, or a junked appliance that has no parts of interest to me. But some days there may be a treasure
if I don't mind breaking it down and separating the valuable from the not-valuable. One day it may be a broken weight machine, with lovely 1" thick steel slabs for the weights, and 1" rods that guide the weights, and some nice structural tubing (square and round) ... just needs to be cut up into usable parts. A week or a month later, there may be an obsolete piece of lab equipment, which happens to have a 1/2" thick aluminum base and 2' long, .75" diameter rods on which the mechanism adjusts up or down ... and a bunch of other odds and ends of dubious value which have to be stripped out and returned to the scrap bin. From time to time there may be discarded electric motors, anything from a 1/10 hp blower motor to a 3 hp 3 phase pump motor. Sometimes the motors work just fine; often they at least need repairs (e.g., brazing up the broken end bell); and often they are simply scrap - but there is a nice 1/2" or 5/8" or 3/4" shaft that can be pressed out and tossed in the bin. Sometimes there is an assembly the function of which I cannot fathom, but it consists of heavy angle iron or channel or square tubing ... again, disassembly required.
Of course, a lot depends on what one is looking for at any given time. I mentioned pipes - often too rusty and crusty to be worth messing with, but sometimes in decent condition; I may or may not take some, depending on whether I need to restock my pipe supply. (What do I use it for? A recent example would be welding up a stand to store my canoe; another recent example, still in progress, is to serve as rollers for a slip roll machine I am building.) Likewise, I mentioned junked appliances - each one is a supply of 20-gauge (or so) sheet steel if I happen to need some. I have salvaged enough to have a more than adequate supply on hand, and I have also salvaged plenty of sheet stainless of similar gauge, from lab or commercial kitchen equipment, so these days I usually leave new such additions in the bin. Recently, though, I salvaged some lab equipment that used sheet aluminum of a similar gauge, because I didn't have much in the way of aluminum sheet.
You get the idea. The key is time and patience, a willingness to "fish" to see if there is anything of interest, a willingness to deal with disassembly. And of course, above, all, a relationship with an institution that, over the span of years, in its normal operations, generates a fair bit of scrap of all kinds. No, wait - above even that, a spouse who tolerates my tendency to come home with "dubious treasures"! She always gives me a hard time about it, of course.
I should add that a supplemental source, especially of heavier sheet (6mm or 1/4" in particular), is a friend who has worked at various companies, some of whom have been generous in their scrap policy. Not all are, of course, but once in a while he calls me up or just stops by and drops off a 2' x 4' sheet of 1/4" thick steel, or something similar. Occasionally I get gifts from others ... being known as someone who is happy to receive scrap has generated at least some of the stock I have on hand.
