Although I don't think this matters, here's some info about the specific products I used:
1) Cyanoacrylate glue: Starbond EM-02.
2) Nitrocellulose lacquer: Deft Interior Clear Wood Finish, rattle can, gloss. They have since rebranded to ProLuxe.
3) Drying tung oil: Minwax Antique Oil Finish. Now discontinued, but other catalyzed tung oil products are available from Minwax, Watco, etc.
4) Shellac: Zinsser, rattle can.
5) Polyurethane: Minwax 33050, rattle can, gloss. I didn't try water-based PU, but based on prior experiences, I'd expect waterborne products to be less durable.
Do not underestimate the "none" option. Even outside it holds good few years, then needs to be replaced. For simplest outdoor applications it is the easiest, most ecologic and sometimes even the cheapest option.
I did some experiments with this before, actually! I think most of this is bunk. In particular, with thinners or without, oils don't really penetrate wood to any appreciable depth, except for exposed end grain - which is usually not the exposed surface in most woodworking projects.
I finished and then cut apart a bunch of pieces, and the application process and thinning did not seem to matter the slightest. Oil is a surface finish, just like polyurethane, except it builds up more slowly due to the usual wipe-on application process.
In any case, the wood was run through a drum sander at 80 grit to get uniform finish, and then coated with three layers of each finish as per manufacturers' spec. The product used here wasn't pure tung oil, as it takes forever to dry; it was a pre-catalyzed and pre-diluted formulation from Minwax, as per my other comment. I didn't sand or use steel wool between coats, because I wasn't trying to get any particular surface appearance, and wanted to give the coatings a chance to seal all grain.
Thanks for this post. I've taken up woodworking recently as a (useful) hobby and have bought many tools to help me, including a superb Milwaukee M18 fuel router, a circular saw and couple of sanders. I live in Brighton in the UK and my home is about 100 yards from the seafront so anything made of wood kept outdoors weathers fast whilst high humidity makes untreated wood (and also leather) get mouldy if left unused for a while, including indoors. I bought a 500ml tab of polyurethane coating couple of weeks ago so I'm really glad it works so well. I haven't used it yet, but am planning to apply it to my new plant potting bench.
I'm curious about how combinations or different application techniques would fare. Sadly cannot try under similar conditions as I live in a tropical area
Some examples:
- 2 or 3 applications of CA glue, waiting for each one to dry in between applications, as this may mean layer 2 or 3 soaks in less
Sun and rain probably do most of the heavy lifting here! In the winter, wood decay is largely arrested, freeze-thaw cycles can only do some mechanical damage.
Where I live now (southeast asia), insects like ants / beetles / bees / termites etc. love wood and there are lots of fungi too. It never freezes, so things don't really die for part of the year or have a hibernation period.
Humidity is also very high year round and there is salt in the air that corrodes anything metal within a couple of years, though may help the wood a bit. There is constant sun for 6 months and constant rain for the other 6.
It is quite different from living in a hilly lowland area of Europe, so after a few years I am still getting used to what I can leave outside or what will go moldy or get eaten.
OK now try those natural finishes with an added dash of boron, that should keep the fungi out. And or pretreat with acetic anhydride to modify the ends of the cellulose molecules so that they are less vulnerable to attack.
If you find anyone willing to sell you acetic anhydride, this will probably be followed by a visit from the DEA.
As for boron, it's a metal(loid). I'm guessing you mean something like disodium octaborate? I suspect it's not soluble in most finishes, but you could pretreat the wood with a solution in water. But then, I'm not sure why this is a useful test - no one treats DIY furniture with a pesticide first, so what does this teach us?
As for using boron salts, not an issue as the toxicity profile is less than table salt, and here in Australia our soils are actually deficient in it, so we add it to our "nitrocal" fertilisers as a trace.
I learned this when looking at how to avoid using things that are far more harmful or are more expensive. The termites here will eat the leg off a pirate if he lays down for a nap but the fungus they farm with that acquired cellulose are particularly sensitive to traces of boron .
I think a similar experiment (maybe like in the sun but not in the rain? Or even just inside in a window?) that’s not quite so aggressive would be fun. Maybe I’ll do that at some point myself. To me fully in the rain furniture is pretty extreme
Well, outdoor furniture is a thing!:-) But yeah, this is a fairly extreme regime. There are harsh environments in the home too - cutting boards and dining tables come to mind - but it's hard to design an experiment where different finishes would be subjected to exactly the same abuse.
Although I don't think this matters, here's some info about the specific products I used:
1) Cyanoacrylate glue: Starbond EM-02.
2) Nitrocellulose lacquer: Deft Interior Clear Wood Finish, rattle can, gloss. They have since rebranded to ProLuxe.
3) Drying tung oil: Minwax Antique Oil Finish. Now discontinued, but other catalyzed tung oil products are available from Minwax, Watco, etc.
4) Shellac: Zinsser, rattle can.
5) Polyurethane: Minwax 33050, rattle can, gloss. I didn't try water-based PU, but based on prior experiences, I'd expect waterborne products to be less durable.
Do not underestimate the "none" option. Even outside it holds good few years, then needs to be replaced. For simplest outdoor applications it is the easiest, most ecologic and sometimes even the cheapest option.
Thanks for bursting the bubble on tung oil! 😄 But I have to push back a bit—applying tung oil is almost an art form in itself. It requires patience and technique. I’m curious about your process—how many coats did you apply, and what mixture ratio did you use? (ref https://paulsdiy.solutions/uncategorized/how-to-apply-tung-oil-properly/#Proper_Tung_Oil_Application_and_Surface_Preparation)
I did some experiments with this before, actually! I think most of this is bunk. In particular, with thinners or without, oils don't really penetrate wood to any appreciable depth, except for exposed end grain - which is usually not the exposed surface in most woodworking projects.
I finished and then cut apart a bunch of pieces, and the application process and thinning did not seem to matter the slightest. Oil is a surface finish, just like polyurethane, except it builds up more slowly due to the usual wipe-on application process.
In any case, the wood was run through a drum sander at 80 grit to get uniform finish, and then coated with three layers of each finish as per manufacturers' spec. The product used here wasn't pure tung oil, as it takes forever to dry; it was a pre-catalyzed and pre-diluted formulation from Minwax, as per my other comment. I didn't sand or use steel wool between coats, because I wasn't trying to get any particular surface appearance, and wanted to give the coatings a chance to seal all grain.
Thanks for this post. I've taken up woodworking recently as a (useful) hobby and have bought many tools to help me, including a superb Milwaukee M18 fuel router, a circular saw and couple of sanders. I live in Brighton in the UK and my home is about 100 yards from the seafront so anything made of wood kept outdoors weathers fast whilst high humidity makes untreated wood (and also leather) get mouldy if left unused for a while, including indoors. I bought a 500ml tab of polyurethane coating couple of weeks ago so I'm really glad it works so well. I haven't used it yet, but am planning to apply it to my new plant potting bench.
I'm curious about how combinations or different application techniques would fare. Sadly cannot try under similar conditions as I live in a tropical area
Some examples:
- 2 or 3 applications of CA glue, waiting for each one to dry in between applications, as this may mean layer 2 or 3 soaks in less
-tung oil then CA glue
-tung oil then shellac
-CA glue then shellac
-tung oil, then ca glue then shellac
Sun and rain probably do most of the heavy lifting here! In the winter, wood decay is largely arrested, freeze-thaw cycles can only do some mechanical damage.
Where I live now (southeast asia), insects like ants / beetles / bees / termites etc. love wood and there are lots of fungi too. It never freezes, so things don't really die for part of the year or have a hibernation period.
Humidity is also very high year round and there is salt in the air that corrodes anything metal within a couple of years, though may help the wood a bit. There is constant sun for 6 months and constant rain for the other 6.
It is quite different from living in a hilly lowland area of Europe, so after a few years I am still getting used to what I can leave outside or what will go moldy or get eaten.
OK now try those natural finishes with an added dash of boron, that should keep the fungi out. And or pretreat with acetic anhydride to modify the ends of the cellulose molecules so that they are less vulnerable to attack.
If you find anyone willing to sell you acetic anhydride, this will probably be followed by a visit from the DEA.
As for boron, it's a metal(loid). I'm guessing you mean something like disodium octaborate? I suspect it's not soluble in most finishes, but you could pretreat the wood with a solution in water. But then, I'm not sure why this is a useful test - no one treats DIY furniture with a pesticide first, so what does this teach us?
Ah well yes acetic anhydride is a tad "industrial". But you could DIY it https://www.youtube.com/watch?v=9ETdZoiWLWM
However pretreated lumber may be available too.
As for using boron salts, not an issue as the toxicity profile is less than table salt, and here in Australia our soils are actually deficient in it, so we add it to our "nitrocal" fertilisers as a trace.
I learned this when looking at how to avoid using things that are far more harmful or are more expensive. The termites here will eat the leg off a pirate if he lays down for a nap but the fungus they farm with that acquired cellulose are particularly sensitive to traces of boron .
I think a similar experiment (maybe like in the sun but not in the rain? Or even just inside in a window?) that’s not quite so aggressive would be fun. Maybe I’ll do that at some point myself. To me fully in the rain furniture is pretty extreme
Well, outdoor furniture is a thing!:-) But yeah, this is a fairly extreme regime. There are harsh environments in the home too - cutting boards and dining tables come to mind - but it's hard to design an experiment where different finishes would be subjected to exactly the same abuse.