Talk Composites - The Forum for Advanced Composites

Resin side table

http://www.talkcomposites.com/Topic23694.aspx

By olly_h - 7/27/2017 9:11:33 AM

Hi, 
I recently came across these tree stump resin side tables and I'd love to have a go at making one. 

I planned to make a mold out of melamine laminated particle board with a mold release. I assume the best resin to use is the Water clear polyester. Obviously it'll require a lot of resin cast in many layers. Any gerneal advice on procedure would be greatly appreciated.
Can witness lines be sanded and polished out?
I assume the tree stump will need to be kiln dried?
What's the best way to avoid bubbles in such a large mold? It will be to big for a pressure/vacuum vessel.



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By Warren (Staff) - 7/27/2017 11:41:15 AM

Most of the ones we have seen were, as you say, done with a water clear polyester, often pigmented.  They would use a large bucket or similar vessel in polypropylene or a release coated plastic.  The logs are then inserted and the resin poured in stages until the bucket is filled.  You can normally pour it in layers around 15cm thick as the logs absorb a lot of the heat so the typical volume pouring restriction doesn't quite apply.

Once cured for a minimum of 48 hours, the block is de-moulded, sliced in a big saw to suit, then finished off as you would prefer for your product.

For clear resin applications, it is normally impractical to degas the whole thing, so the resin would be degassed before pouring and care taken during pouring to reduce any bubbles created.  It can help to brush apply a layer of resin to the wood to seal the wood before the main pours.