Building a seesaw with sliding seats

WoodTimber, lumber. The hard fibrous lignified substance under the bark of trees & wood size explanations

The measurements throughout this project are given in both standard (inches) and metricMillimeter measurements. (millimetres).
The standard measurements (inches) are given first followed by their metric equivalents in brackets.

Use a treatedPressure treated. Refers to lumber that is treated in such a way that the sealer is forced into the pores of the wood. Refers to lumber pressure sprayed with chemicals to lengthen its life expectancy for outside use or inground applications. dressedSurfaced; planed; smooth; even surface; gauged. (surfacedSee Dressed., dimensional) wood. Dressed wood will actually be less than the sizes (width, thickness) given in this documentation.
Make any necessary allowances – easy peasy.

How strong to be!

My grandkids tend to be a bit rough-and-tumble when it comes to using the play structures I make for them.
To compensate, I pretty much tie everything together with galvanizedCovered with a protective coating of zinc. metal strapShort lengths of metal strap 25×1 (1/16×1) used to fix members together to resist uplift. or similar fastenings to ensure minimal give or pull. I like to make sure the things I make are going to be around for a while and are able to take any punishment likely to be dished out to them.
Such fastenings are optional for this project. Good glue and screws alone should suffice in a gentle world, but,… by using the extra fastenings, for little extra cost you can have a much stronger unit. it’s entirely up to you.

Safety notes

Make and use at your own risk.

Many a mishap has occurred on a seesaw so all due care should be taken.
Kids should be supervised by a responsible person (assuming you can find one).

A tire under each end of the seesaw can take away a bit of the jar when one kid jumps off quickly without warning (usually on purpose) while the other’s up in the air.
Baring all that, there’s a lot of fun to be had.