Sandpit with built in seats and lid - metric

Submitted by mrs_dt on Tue, 07/08/2014 - 01:49

This was our first build from this website and we are so pleased! Having seen very involved plans on an Australian website for a similar sandpit, I was so pleased to come across this version, with its far simpler design!
We wanted a slightly bigger sandpit, so I needed to do some modifications, and while I was enlarging it, I also converted to metric sizes, and designed specifically for the timber I knew I could buy locally (very obscure and inconsistent seeming German sizes). So the end result is a 1.5x1.5m sandpit, that has so far had 6 kids playing happily in it at once!
I've put in the drawings I used, and the cutting list for larger sizes in case anyone else is working in metric, or wants a bigger size!
Our other modification was to offset the shorter sections of the base to run along the front plank of the bench seat - there were two main benefits for this - we need a lot less sand, as there is none wasted under the seat, and the seat is supported and can't bow downwards!
The dimensions and layout we used are in the images.

Supplies

Timber
2 - 200 x 40 x 3000mm
6 - 120 x 24 x 3000mm
1 - 80 x 50 x 3000mm

Hinges
12 - 140mm long (the original design had 8, we went with three per edge to allow for the extra width)

Self tapping decking screws
18 - 5 x 80
48 - 5 x 50
96 - 3 x 20 (or enough for your hinges, depending on the design)

Paint
3 - 375ml PU Acrylic Paint, suitable for exterior use (top planks and seat supports)
1 - 750ml PU Acrylic Paint, suitable for exterior use (base)

Weed matting and staple gun

Sand
I calculated I would need 20 x 25kg bags - in the end we needed 11 - don't ask me where we went so wrong!

Cutting list

2 - 200 x 40 x 1500 (long sides of base)
2 - 200 x 40 x 1415 (short sides of base)

12 - 120 x 24 x 1495 (top slats - just under half a plank, to allow for waste)

4 - 80 x 50 x 245 (armrests / seat braces)
4 - 80 x 50 x 495 (back supports of seats)

I gladly paid 5 Euro for the wood to be cut in Hornbach - it should have been more than this, but the guy was generous!

12 hinges (the original design had 8, we went with three per edge to allow for the extra width)

On Sunday we had the idea, on Monday I drew up the plans, on Tuesday I went shopping! Once all our wood was home safely, we sanded it down - most edges weren't badly finished, but there were a few splinters that needed getting rid of!
The next two nights Mr W gallantly set to work with the paint brush. After two nights, the wood all had two good coats of paint and we were ready to start assembling on Friday.
I pre-drilled the base of the bench before the second coat of paint - three holes for each butt joint - with some careful measuring this made screwing the base together really easy!
The top planks were also pre drilled, but there unfortunately my tiredness made me make mistakes, and some had to be re-drilled! Spacing the planks out took a lot of time, but I am glad I made the effort. I used cereal box, and experimented with different numbers of layers - I knew I wanted a theoretical 5.4mm gap, but it took some time to get the right number of layers of carefully creased and concertinaed card!

Having got our spacing wedge sorted, we screwed the blue planks in place at either end of the base. We then assembled the green seat section, and the blue/yellow back rest. Following a tip from the comments section, we added the hinge to the seat/back combo first, as this ends up being on the underside. Once those two hinged sections were made, they were then laid in place on the base (card wedge spacers in place) and then the final hinges added. The final assembly took about 5 hours - but this was partly because we started outside, then had to move everything inside when a huge thunderstorm rolled in!

The next morning we got busy with the staple gun and tacked weed matting over the base, then it was hauled in to position and filled up! For us getting this done and dusted was important, otherwise it could have dragged on a lot, but we are terribly proud that it was done in less than a week from being fist conceived!
I hope the metric/enlarged plans are of use to someone else too. One other idea we had, which we didn't get round to building in, was a support bar to be fitted when you close the pit, so the kids can play on top as a stage when it is not being used for a sandpit!

Built from Plan(s)
Estimated Cost
150 EUR
Estimated Time Investment
Weekend Project (10-20 Hours)
Type of Wood
Pine
Finish Used
Painted with two coats of Polyurethane Acrylic paint
Recommended Skill Level
Beginner