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Forming and Framing
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This was about 20 years ago so I think I'm safe. I once set pier bolts for columns for a three story building, a whole row of them about 1/4" off. I set the first column wrong and pulled off from it and the rest went wrong as well. I had to buy the iron workers two cases of beer to slot the
Column bolt plates. I don't think we were suppose to cut them, but the inspector didn't say anything and I kept my job.
This got me thinking, i have seen embeds being shot in with a total station or transit.. What exactly are you shooting.. i know the location, but on your plywood template so you make a centre mark, and position by exact centre, or by edge or what?
 

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Forming and Framing
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Yup, gridlines. Sometimes you can see them on the underside of the slab where the original chalklines were snapped. Center of columns is another common place to snap a line to get a parallel/square line. You can never trust someone elses layout though so we usually have to go back to the plans and find out where the gridline is and re-establish it. We just had to tear apart a nice curved fountain form because the elevation line that someone else marked all around the parkade was 3" too high.

When laying out long runs of columns.. how is it done? It would make sense to me to find the end points and snap lines but i don't know commercial work procedures. Also, how practical is it to snap the CL of a column? considering all the rebar protruding.. Is it normally a centre mark, or and edge mark to set the corner to?
 

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FramingPro said:
This got me thinking, i have seen embeds being shot in with a total station or transit.. What exactly are you shooting.. i know the location, but on your plywood template so you make a centre mark, and position by exact centre, or by edge or what?
I shoot my anchor bolt layout by swinging angles with the total station. I just shoot an offset mark for my template and double check. These things must be dead nuts. This is something you really can't explain you just have to do a few times.
 

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Hack
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I like doing stair forms, and don't really get a chance to do them all that often so it was nice to get this set done.
This is just prior to bracing and pouring:


Slope Roof Technology Land lot Grass
 

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Forming and Framing
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I shoot my anchor bolt layout by swinging angles with the total station. I just shoot an offset mark for my template and double check. These things must be dead nuts. This is something you really can't explain you just have to do a few times.
So the templates themselves must be cut pretty precisely too I take it?
 

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So the templates themselves must be cut pretty precisely too I take it?
Yes, but this is only how I do it. This is not the only way to do it. You have at most 1/8" play in anchor bolts. Again I only do it this way because this is how I was taught. IMO layinging out grade beams, caissons, and piling is harder. I have only ran one ground up, so I'm sure more experienced guys have other ways. I know the guys who taught me building layout sure were a lot more experienced than me. But the most important thing is making sure your right before you pour. These are not residential sidewalks that can be built a little out and nobody will notice. If your off, or your concrete fails one of the tests your jack hammering back out to redo it. The other thing is a lot of future remodels, control lines will be struck off of these columns so it's helps people out down the road
 

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YUUUUP!
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total station and when we moved tables and needed to pop control lines we would use a PLS. someone would be underneath the tables and measure the distance between the existing control line and the laser
 
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