Polyurethane, Osmo or others for a cup?

[twodoctors]

Hi all,

I was bored, and instead of making bandsaw boxes, I made a few bandsaw cups instead...

...not sure whether it's going to be a drinking vessel or a pen holder yet. (The joint/glueing looks a bit suspect on one of them.)

Is polyurethane the way to go? Or is Osmo going to be ok? Would it be safe with hot drinks as well?

Thanks in advance.

Adrian

 

[custard]

Personally I wouldn't use Osmo or Polyuethane (and certainly not a water based poly) for this application.

I'd either use nothing or a high temperature resistant epoxy.

 

[CHJ]

Drinking? Toxicity? what wood, & what adhesive did you use?

Drinking vessels are normally carved from the solid or coopered* as far as the liquid contact areas are concerned.
Very difficult to ensure any coating other than an epoxy renders the wood totally impervious to moisture ingress, even that can fail if the wood moves,
as Custard says.
If the wood and glue is Food Safe then nothing at all is the most viable, perhaps soaked in melted Bees Wax. to reduce the moisture ingress.

*obviously coopered, (no glue) relies on moisture ingress to swell the wood & render watertight.


Food Safe:- is far more stringent than Child Safe, Food safe means it is safe to add to Food Stuffs for consumption.

 

[twodoctors]

Good point. Pen holder it is then!

It's a mixture of spalted beech, Ash and Sycamore...

Pvc and mitre bond for glue.

I thought a thick layer of urethane might be enough.

(maybe I should get a lathe!)

Adrian

 

[Sheffield Tony]

Beech and sycamore are traditional choices for food contact, but not spalted, that's halfway rotten already !

I've used goblets made from ash and sycamore, with melted beeswax impregnation as mentioned above. Not for hot drinks. Whisky and other spirits slowly strip the wax. Red wine showed where it still soaked through the porous short grain of ash. But for mead, they are perfect !