> Thanks for the link to your previous thread on this subject. I tried to find it by hadn't located it yet.
There are at least a couple more.
[msg=11252]Rubbing Bars for Fun and Profit[/msg]
> The very first thing to do is to measure the distance between the deformations (transverse ribs) on the bar and determine its nominal diameter.
Most of the old rebar around here doesn't have a diameter -- it's square in cross-section, occasionally square and twisted. The twisted kind doesn't have any other deformation, but the untwisted kind has a regular pattern to it.
Ransome bars
> Most of the old rebar around here doesn't have a diameter -- it's square in cross-section, occasionally square and twisted.
This link discusses one of the early inventors who experimented with reinforced concrete using twisted bars. Note that his first major effort was in San Francisco.
Ransome bars
Don't remember where I got this from, but had it saved. We also find some early examples of ransome bar around here in western NY.
Rebar has been the monument of choice in Central Maine since the mid-'70's -- before that steel ("iron") pipes were more common. I know of one case of rebar being used in a subdivision in the '60's -- I suspect there are others. One guy in the 70's started using those 2-foot steel stakes they sell for garden fencing and he stuck with it. I don't mind, since when I find one I know who set it. Some belittle the "2-bit rebar" on this board sometimes --wish I could buy one for 2 bits. But they seem to endure and can be bent onto position if well-anchored. Their use is fairly predominant around here nowadays.
I'm actually a little leery of the smooth bars I find. Who set this? Where'd they get this stuff?
I've never taken too much notice of the types of deformations the bars have that we buy. I'll keep my eye on the variations.
Ransome bars
I find that most "older" rebar around here to be cup and diamond bar.
Ransome bars
Some square rebar exposed in a WPA built concrete bridge in Kingfisher County, OK
Ransome bars
I posted that image back on June 5. It is from a 1912 book I have.
Update:
I returned to the rebar in question. It is a typical "cup" rebar with a coating (paint/primer). Since this rebar is in the raised bank of an irrigation canal that was constructed in the late 30s early 40s it is not the original corner per the plat.
Speculative theories:
1. The rebar is a perpetuation of the corner by the surveyors/engineers working on the canal
2. The rebar is a control point used during the construction of the canal
3. The rebar was set as the center 1/4 before recording laws in Oregon
