Swing Project - Engineering Advice Needed

[sand_man]

The anchor points are about 18' up. And I was trying to obtain a very natural (that word again) swinging motion.

[sand_man]

So now, we're thinking about cutting and using one of those smaller trees in the left corner to use as a horizontal beam.

[vash]

Originally Posted by flipper35

You could put a chain/rope across 4' above the seat to pull them together to hold onto easier.

Yes, that pic is what I was getting at.

this changes everything. this would work.

hey flipper i think we are hiring!! wanna job?

[KFC911]

Originally Posted by sand_man

The anchor points are about 18' up. And I was trying to obtain a very natural (that word again) swinging motion.

I think you could go with your original idea with a big thick rope across the span. A few loops around each trunk (above the small branch nook) and cinched good & tight in some fashion...Cliff can engineer the knot

[sand_man]

Originally Posted by flipper35

You could put a chain/rope across 4' above the seat to pull them together to hold onto easier.

Yes, that pic is what I was getting at.

So I'd have to make the swing ropes extra long so that when I pulled them together, I'd end up with the correct final length.

[sand_man]

This just looks bad:
https://www.etsy.com/listing/467203899/swing-hanging-kithanging-a-swings?gpla=1&gao=1&utm_campaign=shopping_us_WoodSwings_sfc_osa&utm_medium=cpc&utm_source=google&utm_custom1=0&utm_content=5432904&gclid=Cj0KCQjw1-fVBRC3ARIsAIifYOO002ij7a6tO3upkK7hyyA3SLBkrEjE9QnF S0Fec3SC6rpTD7DMVR4aAogiEALw_wcB

[red-beard]

[wdfifteen]

Originally Posted by KC911

I think you could go with your original idea with a big thick rope across the span.

You need something rigid between the trees. It will take a lot of Viagra to make that rope work.

[sand_man]

Originally Posted by red-beard

I'm an IT Business Analyst and Product Owner! I have used this cartoon in more PowerPoint presos than I care to admit! LOL!

[ckelly78z]

Originally Posted by sand_man

This just looks bad:
https://www.etsy.com/listing/467203899/swing-hanging-kithanging-a-swings?gpla=1&gao=1&utm_campaign=shopping_us_WoodSwings_sfc_osa&utm_medium=cpc&utm_source=google&utm_custom1=0&utm_content=5432904&gclid=Cj0KCQjw1-fVBRC3ARIsAIifYOO002ij7a6tO3upkK7hyyA3SLBkrEjE9QnF S0Fec3SC6rpTD7DMVR4aAogiEALw_wcB

Not an engineer here, but a mechanical mind none the less. Wouldn'there be two different pivot points (one a few feet above the riders head, and another at the knots on the tree 18' off the ground) on the swing above, which might make the swinging experience a little awkward ? It would just seem to be a two-stage swing that might give a not so smooth effect ?

[MBAtarga]

Originally Posted by red-beard

That is EXACTLY the image I thought of when I opened this thread!

[pete3799]

A piece of pipe spanning the trees would work better. I'll let Cliff determine the size of the pipe needed. Then either drill it for some eyelets or weld some on at the desired spacing

[ckelly78z]

Originally Posted by pete3799

A piece of pipe spanning the trees would work better. I'll let Cliff determine the size of the pipe needed. Then either drill it for some eyelets or weld some on at the desired spacing

A pipe would solve the sagging/sideways tension, while you could still run the rope through the pipe to attach to the tree trunks in a loop. Screw on a round floor base flange to each side to lessen the damage to the tree, and tie a rope through the flange holes tightly.

[sand_man]

Originally Posted by pete3799

A piece of pipe spanning the trees would work better. I'll let Cliff determine the size of the pipe needed. Then either drill it for some eyelets or weld some on at the desired spacing

A pipe is an excellent idea! I had not considered that!

[Eric 951]

You could also run 5/16" wire rope between the trees using Crosby clamps to secure it to itself once looped around the branches. Fit a rubber sleeve over the wire rope where it contacts the branches to prevent it from digging into the wood. Tension as necessary, and use (2) additional Crosbys on either side of each swing rope(total of (4) to keep the swing centered on the cable, use oversized washers between the swing hangers and Crosby to allow smooth movement, and use a carabineer to attach swing rope to wire rope.

[sand_man]

Originally Posted by Eric 951

You could also run 5/16" wire rope between the trees using Crosby clamps to secure it to itself once looped around the branches. Fit a rubber sleeve over the wire rope where it contacts the branches to prevent it from digging into the wood. Tension as necessary, and use (2) additional Crosbys on either side of each swing rope(total of (4) to keep the swing centered on the cable, use oversized washers between the swing hangers and Crosby to allow smooth movement, and use a carabineer to attach swing rope to wire rope.

Yes, I think "crosby clamp" is what I was really thinking when I said "U-bolt". Thank you for the correction.

[dad911]

OMG, I'm an engineer, and you guys are way over thinking this. Tie a rope to each tree, a tire in the middle, and let the kids have fun. If you really want a classic swing, connect a 4x4 to both trees and attach swing to it.

How much of a hill is there? It's best to swing out over the hill.

Or tie a cable to a tree on the hill about 10' high, other end to the house or a lower tree, and attach a pulley to a T handle.

[flipper35]

Again, those trees are going to move a great deal when there is wind so any beam or pipe attachment will have to account for that movement.

[flipper35]

Personally I would do a zip line also.

[derek murray]

Wrapping anything around the trunk or a branch may, in time, kill the tree or the branch.... aka "girdling" (the tree's vascular system runs just inside the layer of bark). I might consider this, instead. Boring through the trunk of a tree will not kill the tree. It would be easy to try and you'd know quickly whether the tree could withstand the forces of unfettered swinging.