Drove all the way to Oelwein to the only sale on Friday that said"tools". Most were overpriced and of minimal value, but I did find three things to spend $5 on. The Crescent wrench is in average condition and the Klein knife has seen its better days, but this Challenge Cutlery Corp, Bridgeport CT. caught my eye, especially since I'd never heard of them and the patent date of 1904. VERY little info on the internet about their tools, but plenty on their knives. I have an email in to one BF (blade forum) member that had one of these steel squares for sale and advertised as "rare". Waiting for a response, but while I'm waiting, I didn't want to short change our gurus from giving their knowledge on the item. The Klein knife looks old but I think I've seen one or two on ebay before. Model 1570-3.
Wish I had found more, but $3 for a rusty Disston-Porter hacksaw was too rich for my blood and the old power tools were high as well.
Thanks all
DM&FS
Bette refresh my photo posting skills...
datamp has a patent for a square associated with challenge Cutlery, tho it does not look like that one, it might somehow be functionally similar....hmmm
http://www.datamp.org/patents/search/advance.php?pn=768324&id=15492&set=2
It's more, to my eye, similar in construction -- all the sheet metal bending. I have one (which I can't find 'cause my pile on the back porch has grown too much). Your basic first speed-square, I thought. But there is an even earlier patent for a square that looks virtually identical, 1850 something I seem to remember. It's been a very long time since I saw that early "speed square" but I think it was patented or produced by somebody named Fox.