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Hang Test Advice.


dmwood
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Need to set up a hang test in my garage folks. Question is what method shall I use to fix my ropes to the garage roof joists.

The joist is a 6" x 2" so is it safe to hang all up weights 120-140kg from a single joist? If so what method should I use to fix the ropes?

Would drilling 2 x 1" holes in the centre line of the joist to thread the 16mm nylon ropes through be ok? Or should I get something like this

http://www.sugarrays.co.uk/shop/heavy-duty-ceiling-hook.html With this I would be worried that I would split the joist trying to wind coach bolts in to it.

Finally is there another easier way that involves no risk to my garage roof and I am not thinking straight???

Advice appreciated !

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Couldn't you hand the other way round so you can fix the ropes to two individual joists?

That way you are spreading the load over two.

If you drill a hole for the rope drill it at the very top of the joist so that the maximum width of joist is undisturbed.

Cheers,

Alan

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Darren i would be care full with those things..... If there from home base then there made from chocolate!!!

A hole in the joist is a much better and simpler way to do it :wink:

These ones are from B and Q, made of dark chocolate, and so are much stronger!!! :wink:

Seriously though I hung off them in my free flying harness first and jumped up and down, pulled from side to side. Nothing budged, no creaking or snaping noises, so then I went the next step and hung in the motor harness.. it was fine.

I only used one piece of rope threaded through the two eyes at the top so it was easy to level out as well. :D

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I only used one piece of rope threaded through the two eyes at the top so it was easy to level out as well. :D

Seriously would use two pieces if you are going to do this, one piece of rope will cause the eye bolts to pull together and make them very loose.

I personally would not use eye bolts at all ... a hole through the top of the joist is perfect.

Carl

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I only used one piece of rope threaded through the two eyes at the top so it was easy to level out as well. :D
Seriously would use two pieces if you are going to do this, one piece of rope will cause the eye bolts to pull together and make them very loose.

I personally would not use eye bolts at all ... a hole through the top of the joist is perfect.

Carl

Point noted regardng the potential to pull the eye bolts together. The joists in my garage roof are almost the same distance apart as the swing arms on the paramotor so I believe there is very little shear force acting on the eye bolts. I will take another look and decide what to do as I have spare rope to set up two individual lines.

The suggestion that drilling a hole in the top of the joist is best because it leaves more wood below the hole is wholly incorrect..

The hole should be drilled in the centre line of the beam where the forces acting on it are neutral. The top of a joist is in compression and the bottom is in tension so its bad advice to suggest drilling the hole in the top of the beam as it will be weakened by doing so.

The diagram below shows the principle quite well even though it is for a steel RSJ.

cub_mechanics_lesson10_image3.jpg

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