Wooden Tankards - What am i doing wrong?

[prldoyle]

Hi,
I have made a test Wooden Tankard, my plan is to make them for all the men attending wedding in September.

To make the test one I have used air dried oak, glued it all together (with waterproof food safe glue), sanded it then used T&G treatment oil (details can be found at Tg-woodcare website) . I treated it 3 times within a week and then left it for a week.

After that, i filled it with water and left it for about 5 hours to test to see if it was water tight. It is, however the wood started to turn black along the top of the water line, not sure what it is, it looks like mould.

My question is why is this happening? am I using the wrong type of wood for this project, or am I not treating the wood correctly? Any suggestions would be very much appreciated.

Regards
Pete

 

[custard]

The tannin content in oak is extremely high, so if there are dissolved iron salts in your tap water (as there generally is) it will react with the tannin and go black. I'm surprised it was quite such a quick and strong reaction but not surprised it happened. When I'm mixing up Cascamite adhesive for use with oak I use distilled water for exactly this reason.

You could try a low tannin wood such as sycamore, or you could make them all a cufflink box instead!

 

[nev]

Have a search (using the search function on the right) for goblet finish, rather than tankard as they are far more common than tankards, at least on here anyway.
For example, this thread ...
woods-to-avoid-for-wooden-goblets-t79941.html
Covers your question and may well provide the answer, or at least point you in the right direction.
Pete - 'Bodrighy' makes a lot of goblets and seems to have found a suitable finish as mentioned in the above post.
Hope that's of some help.

 

[prldoyle]

Thanks for your replies, it has been most helpful.

I think i am going to try it with sycamore, and possibly change my sealant as suggested in the post, If this all goes wrong, then cufflink boxes it is!

Cheers
Pete

 

[gregmcateer]

Hi,
I have made a test Wooden Tankard, my plan is to make them for all the men attending wedding in September.

Am loving the traditional approach =D>

Perhaps sherry glasses for all the little ladies, too? :wink:

 

[CHJ]

Don't know how you are assembling them but tradition would indicate that tankards would be coopered and rely on liquid to swell the wood and keep it watertight.

I.E no glue or finish involved.