I hope this is the right forum for this if not please feel free to move. I was wondering if there are woods that you can NOT use for bowls and goblets. I have read a lot on food safe finishes but have not read anything about woods that are not safe for the general public. I under stand some people my be alergic to some wood so I am asking about wood that is toxic to people in general. Thanks
I suppose, the first think that needs to be asked is, are those turned pieces, decorative or for use...???
For decoration, any wood or finish will do however, if the items are going to be used, is good to know what sort of use they are going to get. The reason why I say this is that, while some pieces are self explanatory when comes to its use, such as goblets but bowls, there are an enormous variety of sizes, shapes and uses to them so, a fruit bowl, has to be looked at differently than a salad, soup, etc., bowl...!
This is where the wood type and the finish becomes important, for example, many people is very allergic to Silky-Oak however, you can make a fruit bowl or a decorative goblet with it and seal it properly with some sanding sealer and a couple of good varnish to coats, that will seal any possible reaction people could have from the wood.
There are other woods that don't agree with some people, Walnut is one of them so, the first thing I do when I get and order for a bowl or any other piece, I need to know if there are any allergies known and the used of the piece I was requested to turn. There has been cases where the person had a specific request (wood type) but the use wasn't suitable for such wood so, alternatives had to be found after the person understood the situation.
Any wooden turned pieces that will hold any sort of liquids, hot or cold, special attention should be given on what tom use, wood and finish and while the number of woods suitable is considerable, the same can not be said for the finishes. The issue is as old as man kind, even when there were times where, wooden utensils were the only option. What was used is those days to seal the wood and to maintain it usable, is today a no no and a contradiction to any of the safe food regulations that are implemented in our days so, the modern options are very limited and most totally useless...!
It may be better to void making any turnings and suggest them as suitable for human consumption use however, you can make a "compromise" with wooden items that people want to use occasionally to hold drinks, liquids or foods by lining the inner surface of the turned piece with a good fit, plastic, stainless steel or even porcelain container. The piece will have the wood appearance but all liquids/foods are contained within the inner lining.
You have to make those linings removable so that people can wash them out and slightly rinse if necessary the wooden piece and dry it immediately. Finishes such as Olive oil and natural timber oils can be used to replenish the piece every so often keep it looking good. Some varnishes can also be used, some are quire resilient to water so, a simple wipe and the piece is clean however, sooner or later, it will require re-finishing...!
The issue is a lot more complex than some may think however, is a situation that most of us is confronted with, in the very beginning of out wood turning efforts/careers...!
Hope this helps you a little...!
Cheers
George