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Lockdown swing set

·4 mins

If the kids can’t go to the playground, the playground will come to the kids…

Working from home freed me almost two hours a day of commuting, so we decided to do something productive with it for the kids that are going crazy at home already.

Three weeks from buying the raw material until it opened to the public.

First time I’m welding a construction that needs to withstand significant (dynamic) load. Let’s hope that my calculations are correct 🙂

Some highschool trigo - 16y/old me would have been baffled that it’s useful.

Cutting the profile to size. In retrospec the profile is borderline - 40x40x2mm.

Could have gone with a thicker profile.

While it should carry ~1.5-2 of the expected load, a larger safety margin would have been better.

Parts matching was excellent in one side… and abysmal on the other. Had to use a lot of welding sticks to make up the gaps. If I’d do that again I would first attach the two legs together, then measure the angle, cut, and weld the main beam.

Getting the angles right separately is very difficult.

I used the floor to align the parts. Turns out it’s far from straight… I got weird angles and a twist between the legs.

We’ll fix most of it when we put this in place, adding a bit of tension to the structure as we weld it to the spikes.

Showing the bad along with the good. My welder was not right for this job. It only goes down to 55 amps, so I kept burning the thin 2mm profile. 35-40A would have been better?

Since I kept burning holes through the material, I needed more and more welds to make up for it, since it needed to be strong. Turned out ugly.

As I went a long my welds got better. I found out that gravity has huge impact on my welds, so I tried to avoid vertical welds as much as possible.

I also got better at working with the material at 55A - Instead of starting with a joint seam, I made 2-3 reinforcement seams near the joint, so when I got to the joint I welded mostly thicker welding material and didn’t burn the profile.

I made sure I have at least two “good welds” on each joint, and invited a mechanical engineer to inspect the job (thanks Dad).

UPDATE 2020-05-05: OK WOW!! Bought an electronic welder yesterday and WHAT A DIFFERENCE! Electrode burns a lot cleaner (no spatter), and at 45 amps I don’t burn holes - I can just make one line and that’s it! If I knew the welder will make such a difference I would have bought it before starting the project, finish in half the time and with higher quality welds!

Paint job took 4 days - 2 coats of primer + 2 coats of paint.

Seats are pine wood with 3 coats of varnish.

Installing it in place. Used 30x3mm angle bar as spikes, and welded to the legs. Each is 30-40cm in the ground. Did a load test by swinging an adult quite vigorously. It will hold.

The finished product 🙂 10mm static ropes tied in a boom hitch knot to the main beam. Underestimated the amount of rope I need (by a factor of 2), so ended up with enough rope for just one swing. Had to use an old rope I had laying around. Will replace it with a new rope. Someday.

UPDATE 2024-02-09: Ropes have been replaced with chains, swing still holds.

However, I think it is getting to its end-of-life, and I’ll disassemble it in the summer.

The more I learn about welding the less I’m comfortable with the welds and beams choice. Also the kids have grown up, and I’m considering re-using the space for something more challenging for them.