I have a 4"x10" wood beam that I want to hang a swing from, but the top of it is not accessible (the roof is above).

Would it be more stable/load bearing to do a shoulder eye bolt with a nut horizontally through the beam, with the load being at 90 degrees, or using an eye bolt from below that's screwed into the wood?

I figured the horizontal lag bolt can have basically arbitrary working load depending on the diameter, but i wasn't sure about what the 90 degree load would do to the beam.


  • $\begingroup$ You need to provide more information such as the proposed load, type/grade of the wood, span length, and how it is supported. Note this forum is meant to provide answers to the conceptual questions on engineering, not to offer solutions. $\endgroup$
    – r13
    Commented Oct 22, 2021 at 0:11

1 Answer 1


I would use a 1/8 x 4 x 10-inch plate on each side with a proper pre-drilled hole on it for your eye bolt with four 1/4 inch bolts on each corner.

A swing not supported by a plate will eventually split the beam. Hanging them to the bottom of the beam has its own risks of failure.


Your Answer

By clicking “Post Your Answer”, you agree to our terms of service and acknowledge you have read our privacy policy.

Not the answer you're looking for? Browse other questions tagged or ask your own question.