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Discussion Starter · #21 ·
We are using SS straps, We tried pvc coated and they never seemed to fit correctly.

If you consider how a strap works, The strap pulls the conduit tight against the unistrut. If you added a small wood spacer behind the conduit and tightened the clamp then removed it you would see 2 small indents in the wood where it made contact with the unistut. Now if you imagine its doing the same thing to the pvc coating add a little vibration and the pvc over time will deform which will lead to the clamp being loose. (also happens with most clamps used on pvc coated ridgid). It may take years but eventually the clamp slips and it looks bad.
 

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We are using SS straps, We tried pvc coated and they never seemed to fit correctly.

If you consider how a strap works, The strap pulls the conduit tight against the unistrut. If you added a small wood spacer behind the conduit and tightened the clamp then removed it you would see 2 small indents in the wood where it made contact with the unistut. Now if you imagine its doing the same thing to the pvc coating add a little vibration and the pvc over time will deform which will lead to the clamp being loose. (also happens with most clamps used on pvc coated ridgid). It may take years but eventually the clamp slips and it looks bad.
Yep. Just reminded me of what we did on a vertical rack of 2". We cranked the straps down then pulled them off. Then we cut the PVC off where the strap marked and sprayed the coating on. Next day, we rehung it and strapped it with 2" EMT straps we'd sprayed the day before and cranked the heck out of them. That was only 3½ years ago, so can't tell you long term results.
 
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I went through a welding program and there were a handful of union electricians there getting their AWS certs for welding as it was required for some nuke plant so they could weld their own supports.
 

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I use a fair bit of stainless strut, but it's the type that takes U-bolts for the conduit and not traditional Kindorf-type clamps, so slipping is not an issue.
 

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Discussion Starter · #27 ·
I use a fair bit of stainless strut, but it's the type that takes U-bolts for the conduit and not traditional Kindorf-type clamps, so slipping is not an issue.
I have a sales guy bringing some different style out. We will test it to see if it can handle the vibration with out cracking then go from there.

The machines we use have a cam action and if they get in sync it will make the whole 60 x 100' deck jump.
 
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