Hello all!
I am a novice wood person, and one of my projects is a plant trellis. Do I need to treat the part of the wood that will be in “damp” soil to prevent the wood from deteriorating? I’m currently utilizing GF plywood. Thank you for any help & guidance.
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Yes, your best option would be to either coat it with Plasti-dip, or spray with some other rubberized coating, like Flex-Seal.
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Your best option would be to use cedar hardwood or some other rot-resistant species.
Plywoods are full of chemicals and terrible at surviving moisture.
Before you ask, check out 1a:
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Thank you all!
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I just want to add that GF plywood has an MDF core, which is kind of like glorified cardboard. It makes it lightweight and consistent to cut, but it’s an awful choice for outdoor projects. There are solid core plywoods available, some with water-resistent glue (i.e., marine quality) that would probably be a better choice if you want to use plywood. They’ll still need a good seal, of course. If you search for wood sealers for plantboxes, that will set you in a good direction.
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You could put multiple coats of spar urethane on there to try and weatherproof it that way. But you’d need many coats to possibly succeed.
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Marine plywood is expensive and cuts poorly in the Glowforge. Do not recommend.
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I’ve got marine grade Baltic Birch and haven’t had any issues.
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Never heard of marine grade Baltic birch. Is that really a thing or just people calling regular Baltic birch marine grade?
I’ve only ever seen stuff like okume marine ply in thin format.
Hmm…this doesn’t seem to indicate marine grading:
This seems to shut the door on it:
I’ve seen sites claiming that it’s marine grade but I dunno.
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I misspoke on the Baltic Birch. It’s exterior glue, not necessarily “marine grade.” It’s what I’d probably go with for outdoor projects. In fact, I have used it for some outdoor signage (the letters, not the backing). Time will tell how they hold up, but so far so good a few years later.
Boulter carries that, as well as a series of marine grade plys, several of which should laser just fine. I am not really interested in debating whether they are technically marine grade or not since it doesn’t matter to me in the slightest and it’s not remotely my area of expertise. I’m just suggesting options for the OP to make a trellis.
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My (admittedly unsealed) Baltic birch vegetable stakes totally fell apart within a month. A well sealed piece of Baltic might hold up but plain Baltic sucks up water and splits super quickly. Boooo
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Just my 2 cents.
I work in the resin manufacturing business and supply among other industries to plywood plants.
Most plywood is made with several thin layers of natural wood ply with the grain alternating 90 degrees, and bonded under heat and pressure with urea-formaldehyde resin, which is water soluble. Unfortunately when this plywood gets wet, the layers start to delaminate.
In oposition, marine plywood is made with a much more expensive phenol-formaldehyde resin which is not soluble in water, hence its increased resistance to humidity.
The marine grade adjective is added to any board material bonded with such resin. Birch and pine, being one of the fastest growing forest species, are probably used the most for plywood and particle board.
Also for economic reasons, most plywood and particle board are made with the cheaper UF resin.
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I painted mine with an outdoor paint. They aren’t sitting in the ground, but are subject to pretty extreme temps. I don’t imagine they’ll last forever.
I feel like I need to do an experiment, but I probably won’t.
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In my experience, it engraves and scores beautifully, but is tough to cut. It’s also oily. If you have a scroll/band saw, then engrave the plain board in the GF, score the cut lines, and finish on a saw. Otherwise, plan on cutting multiple times (like twice on 3x passes), and clean your optics like you had been cutting MDF for a week.
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Thank you everyone for your wonderful feedback! I appreciate you all.
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