How much weight can a screw thread hold?

[JoeS]

I like to hang from my ceiling doing chin ups and stuff like that. Awful habit I know. Ive done this successfully for years with stainless eyelet screw bolts.

We have a new house in the countryside where the beams are much slimmer... but anyway... my question is...

Is there any way of calculating how much weight a single screw thread in 316 steel can take, does it matter whether the beams are soft or hard wood. For example the supplier I am looking at has a 5mmx50mm threaded eyelet screw. How much weight would this support?

 

[Jacob]

I like to hang from my ceiling doing chin ups and stuff like that. Awful habit I know. Ive done this successfully for years with stainless eyelet screw bolts.

We have a new house in the countryside where the beams are much slimmer... but anyway... my question is...

Is there any way of calculating how much weight a single screw thread in 316 steel can take, does it matter whether the beams are soft or hard wood. For example the supplier I am looking at has a 5mmx50mm threaded eyelet screw. How much weight would this support?

View attachment 185242

I'd go for bigger. Swinging on 5mm could snap the metal even if the threads hold.
Also longer is better as that gives more grip.

 

[Stigmorgan]

There will be a big difference between hard and soft wood types too, soft wood has more chance of the eyelet pulling out.

 

[Fitzroy]

https://www.engineeringtoolbox.com/wood-screws-allowable-withdrawal-load-d_1815.html no idea of its validity

 

[Cabinetman]

Those are unusually nice eyelet screws, into hardwood they will not pull out, but you will need a pilot hole, you may even need more than one diameter and length of pilot hole. Softwood, not so sure. Try it, and get someone to hang onto your legs, with proviso obviously.
It may be that in a modern house it isn’t a solid joist!

 

[ChaiLatte]

no idea of its validity

And with his intended application, you would have to consider the issue of dynamic loads, not just a static load.

 

[Bingy man]

If you’re concerned that they could pull out under your weight on these thinner beams then why not brace across 3 or 4 joists then use an eyed bolt . Use steel plates or heavy washers and secure a piece of 18 mm plywood. Bolt the eyed bolt through the ply using plates / washers etc it will be super strong and a lot safer ..

 

[Ozi]

Approved engineering method.

1. Calculate to 3 decimal places.

2. Think that's not strong enough.

3. Use the big one you first thought of.

It's kept me employed as a rig designer...someone will always add weight you hadn't allowed for or drill a hole where they shouldn't then blame the engineer.

 

[Fergie 307]

I like to hang from my ceiling doing chin ups and stuff like that. Awful habit I know. Ive done this successfully for years with stainless eyelet screw bolts.

We have a new house in the countryside where the beams are much slimmer... but anyway... my question is...

Is there any way of calculating how much weight a single screw thread in 316 steel can take, does it matter whether the beams are soft or hard wood. For example the supplier I am looking at has a 5mmx50mm threaded eyelet screw. How much weight would this support?

View attachment 185242

316 isn't actually very strong compared to high tensile steel, which will also be much cheaper. Not sure where you will get one as elegant as the one in the picture though !
In terms of a straight pull I would imagine it would hold in hardwood, swinging about on it is another matter. Personally I would be much happier using something that bolted right through the beam, with a nut and washer on the other end. Or maybe a steel bracket between two joists and it bolted through that.

 

[Spectric]

The closest thing I have done to what you are looking to do is hang a cloths airer from cast in style. Fully loaded there is some weight but with no one swinging on it and it was in the ultility room I was refurbing. The roof trusses were the modern matchstick design and what I did was use new timbers from the outer wall plate onto the top of the new built in cupboards which were made in 3 by 2's. I drilled 7mm holes through these timbers to take the 6mm threaded rod attached to each of the three pulleys and used a nyloc nut and large washer on each so not relying on a thread into wood which in your case would be subject to swinging loads.

Why not just get yourself a solid kids swing in the garden and use that frame ?