I used Bill Sapsis book to make this calculations . Did I get it right?


Active Member
I used Sapsis book to make a calculation for UDL in a cantilever.. see image ..

-Truss chart is christie 12 inch truss.

- span of truss is 32'

- A 1 is left of truss 12' in and A 2 is at the end on right.

- UDL is a led wall 14x8 at 18.4 lbs = 2060 lbs

I got A 1 at ~1440 lbs and A 2 at ~644 lbs

Did it got it right? .

1.) When using 1Ton motors is pushing it to the limit?

2 ton better options. ?( For the 1440 lbs point. )

2.)Is 12 inch truss use pushing it to the limit? ( based on chart )

Is using 16 " truss better option?


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What Rigger?

I'm so fly....I Neverland.
Hard pass on this. No comment.


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Fight Leukemia
@Dagger so, I'm sorry to say that you are alone in dangerous territory. The challenge here is that if a real rigger (like the two I tagged) comments on your math they are accepting liability for all of your work. If something bad happens, they become part of the chain of responsibility. So they are not going to take that risk. You might find someone willing to give you a thumbs up on the internet but do you know what their qualifications are?

In situations like this I offer two pieces of advice.
-When in doubt don't do it.
-Bring a qualified rigger onto your work site to check your work and do the math.

Yes it will cost you, but it'll be a lot cheaper than killing someone.

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