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Hey guys, I'm new to wood turning, but recently turned my first bowl. I finished it with Salad bowl finish, which I've heard is vegetable oil?

So question is; what does everyone else use?

I want something food safe, but is vegetable / salad bowl finish it? Is bee's wax safe?


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Well it depends :D

To start pretty much all of the finishes sold nowadays are food safe once cured.

Vegetable oil depends on the type of vegetable, some are a bit apt to go rancid and many don't provide a whole lot of protection. Walnut oil is pretty inoffensive except to people with nut allergies, they don't like it that much for obvious reasons :eek: I've used linseed and tung successfully as well. Beeswax by itself doesn't imho provide a lot of protection, its certainly foodsafe but it isn't super hard or resistant to use. A Carnuba wax blend is a bit tougher but still will get rubbed off in heavy use.

Tung is somewhat more water resistant than most other oils, I did a bunch of taster trays that see hard use in a brewpub and finished them with waterlox which is a tung oil based phenolic and they've stood up real well to a wet and rough environment. Some of the other oils like hardware store "boiled" linseed oil have metalic driers that some folks find objectionable, personally I don't see them as a real concern but you can certainly make up your own mind.

I know others here use wipe on poly or similar finishes, they have their ups and downs as well, but are pretty cost effective, easy to apply and survive fairly well in normal use.

For some pieces I use WoodTurners Finish, which is a water/oil urethane mix. It has a (possible) advantage of drying really clear and not coloring the wood much at all. Sometimes this is nice, other times.. not so much.

Different companies "salad bowl finishes" can vary wildly in formulation, one way to figure out just what the heck is in them is to look at the MSDS. For instance here is the MSDS for Behlens http://www.behlen.co.uk/safety/B603-00014.pdf from which we can deduce that the active ingredients are at least ~10% tung oil in a 40-50% Toluene/Naptha delivery agent and a cobalt drier and about 40% alkyd resin. The alkyd resin provides most of the structure and the Tung oil provides some water resistance. It doesn't tell us what kind of alkyd resin it is (long/short) or what the source oil for that was (probably soya or similar, but mostly functionally irrelevant). A phenolic resin would be slightly tougher, but may not matter a lot in the grand scheme of things.

So what the heck does that mean?
Decorative or low wear bowls I'll just do with a quick oil + wax coating. You have to reapply it every so often but it looks pretty decent out of the box and it quick and easy. Straight beeswax, while perhaps traditional, isn't as durable as a harder wax like a carnuba base (I use mostly Johnsons Paste because its available locally).

For high wear bowls I want a film building finish. I think a phenolic resin+drying oil like waterlox is probably one of the tougher things you can easily put on with minimal equipment, although alkyd resin+oil like the Behlens isn't going to be a lot further behind. Poly is decent and I wouldn't say no, but I've had some more problems with it on other projects if they have a lot of water exposure where the poly will "blush" (turn white), but other seem to have good luck so ymmv.

Finally there are a bunch of other options like lacquer (which makes pretty shiny) or urethane (i.e. woodturners finish - but there are definitely other cheaper options I've been to lazy to explore) which definitely have a place for getting a specific look.

I'm sure there are others or I'm misrepresenting some so don't throw stone to hard please :D

As to a favorite, if you asked three turners which was their favorite I'd bet a doughnut you'd get four different answers.
 
Veggie oil wouldn't a first choice. I can and will go rancid over time. Any commerical finish, once cured , is food safe. Studies have been done on this for years and prove it over and over.
 
Jim is right. Any finish when cured is food safe. Not dry but cured. When you can't smell it then it is cured. I use Drs Workshop walnut oil and walnut oil/wax combo on any I turn and on my personal utility items. I have plates and bowls I have been using now for about 5 yrs that were finished with walnut oil. About once a year I will renew it and they still look like I just turned them. I would not use any veggie oil or mineral oil. IMHO it never dries and is just attracts dust.
 
So, is curing just a matter of time?

Depends on the finish - temperature/humidity/time all factor in for ~most~ of them.

Most hardening/drying oil based finishes are actually oxygen curing (which is why multiple thinner coats cure nicer without the gloopiness you get if you put it on to thick - the thin layer allows the oxygen to react). So in those cases time is the cure :)D) in addition to application technique and environment. In some cases the curing time can be quite long, like if you completely saturate an thicker item with linseed oil the inside may not dry out for a really long time - the cured layer on the outside inhibits oxygen uptake on the inner parts and it just doesn't cure very fast. I've cut apart items saturated with linseed oil months later and had the inside still be wet (and actually use this to advantage for wood handled yard tools - saturate with linseed and if they get some bit of wood abraded off it self cures - magic). Of course this would be less desirable for a bowl. For most of the oil products heat accelerates the conversion process so you can somewhat substitute heat for time (although high temperature direct heat sources also are a fire risk so don't be crazy with it).

Multipart finishes like epoxy or catalyzed lacquer the cure time depends on the formulation (and also temperature/humidity in some cases). We had some epoxy paint in one datacenter that was poorly mixed and 10 years later you still didn't wear your good pants if you were going under the floor cause there were wet spots. No amount of time was going to help there.
 
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