Sandbox Weekend

I spent the weekend building a sandbox for my two little boys to play in. Insane housing prices and an unwillingness over the years to commit to an unpayable exotic mortgage has left me a renter, so it was built at my mother-in-law's house.

There are many options: pressure treated ACQ lumber, plastic/wood composites like Trex, 100% plastic recycled lumber, plain old wood. Of these, I think the 100% plastic makes a lot of sense - it'll last as long as you wish, it can be recycled at the end, no splinters, no toxicity. Wow, that stuff is pricey though - like $10/foot! I have filed away mental notes to revisit that material in the future. Pressure treated lumber, even the arsenic-free ACQ, gives me the heebie-jeebies in the context of constant contact with little hands. Trex type stuff is also expensive, so I went with plain old fir. $22 total for 24 feet of 2x12, cut neatly into 6 foot pieces at Lowe's. If only black locust was commercially available...

For seats I used 3/4 inch red oak plywood. Yes, plywood outside. Very bad, I know. What the heck - it's screwed on, if it rots I'll take it off. Tool limitations prevented me from cutting up 2x6's to make more durable seats. Here's a closeup of a seat. Note the countersunk screws to avoid snagging clothing:
The main boards are attached with Liquid Nails and a trio of 3/8 x 4 inch lag screws. This should be strong enough, eh? Incidentally, ACQ is often used with stainless steel fasteners. The hot-dip galvanized screws I used were 78 cents each...SS was $6.14 each!!
Sorry 'bout the washing out, my cell phone camera sorta sucks. Now, the next issue was finishing the wood. Leaving it unfinished would limit its life. However, being a sandbox about 10 years is all that's needed. I opted to avoid toxic sealants altogether and went with AFM Safecoat Naturals Clear Penetrating Oil. This is basically boiled linseed oil without any lead or other heavy metals that are typically used as dryers in linseed oil. I gave the whole thing 2 coats of oil, top and bottom, dug out the backyard, put down landscape fabric, and will fill the box with 3000 lbs of play sand in 2 weeks when we return. The final pic:
I think it looks pretty nice! I am not looking forward to moving the sand in, 30 wheelbarrow trips will do me in.