fix swingset beam sway?

[DaveS]

A couple years ago I built this big ol' wooden swingset/fort thing in the back yard. I used 2 2x8's lagged and nailed together to form the 16' long beam to hang the swings on.

When the boys were little, it was peachy. But now that they breaking the 40lb mark, the beam is starting to sway a good 3-4" (each way) in the middle if both boys get their swings synchronized.

I took my entire (larger than average, I'm afraid to say) weight and hung on the beam, right in the middle, "jumped" up and down on it, then had my friend hang there with me. So, I'm sure the 2-2x8's are plenty strong in the downward direction.

I'd just like to take the sway out.

I was thinking of using a 16' 2x6 and laying it on top of the 2 2x8's and lagging it every 12-18" into the top of the 2x8's. Maybe even using some exterior polyester glue or liquid nails?

Would that be enough? Or do I need to get some piece of really long angled (galvanized) steel to brace it?

Any ideas?

[LCHIEN]

A 2 x 6 laid flat across the top and attached to the edges of the 2x8's will stiffen it considerably, I would think.
One top and one bottom would make a jiffy I-beam, although you would have to remount the swingsets.

Are you sure the beam is bending (sideways) and not that the end supports are moving? (Not knowing what the end supports are - A-frame???)

[DaveS]

I'm pretty sure it is bending in the middle.

Here's a picture of the swingset. (yes, I finally did get around to trimming off the extra on the 2x6 on the A-frame part)

[Pappy]

Your idea should solve the problem. Most boys being adventurous by nature, my concern would be that they would see it as a walking plank from the fort/tower. I realize they could do that now with the beam, but a wider platform might be more inviting. Maybe add some upper railing on that side?

[rbfunk]

First, I had to double check your location. That looks exactly like my brother's place. No trees, walk out basement, and deks high up.
Now on the swing set, I count 5 swings. Could you lose the toddler swing and/or the 2 seater and add an A frame or a post in the middle?

[leehljp]

I agree with RB on this. Another A frame would be more of a long term solution as the boys grow.

[DaveS]

Just an update...

After reading your advice, I had decided to put in another A-frame and lose the baby swing.

After I told that to my wife, she informed me that all stations were highly utilized, and they all needed to stay (darn neighbor kids).

So I moved on to plan B - the 16' 2x6 hat. I put it on top of the 2x8's and lagged it in every 12" (alternating which 2x8 I sunk it into). One of the 2x8's was 1/8 of an inch taller than the other, so it even has a nice pitch on the 2x6 to prevent the rain from puddling up there.

It really did the trick. I took my big butt for a swing and I couldn't make it budge an inch. It ought to take care of things for a couple years.

I will be sure to keep an eye on it. I'm concerned that as the wet 2x6 on top ages, those lags might loosen up - I'll just have to shoot a few more in if that happens.

I hadn't thought of the temptation of using this as a "bridge", so I think I will eventually put up some rails on top to stop the monkeys. Currently, the boys are too small to leave unsupervised - so we are probably ok for this season.

Thanks for your help...

[mikebanks]

Another Idea.

I saw a guy that used the large screws that go into the ground to hold a dog chain. He used them to anchor the ends of the A frames and then used some wire and some lag bolts to hold everything together. That way the A frame will not lift up on one end. Make sense?

MIke