Split wood and resin

[Penny]

I have a few small logs from a chap I know. He's a woodcutter - mostly for firewood. He and I have an arrangement that if he comes up with any nice logs that he thinks I'll like for turning he'll put them aside.

I raided his stock a few weeks ago. One of the almost dry logs (beech, I think) has split along it's long side after I gave it an initial turn to de-bark it and let it dry a bit more. It was for a candle stick for a pillar candle.

Can I fill the crack with resin, allow it to cure and then turn it? I think it'll give a good effect, but I don't want to cause damage to the log, my tools, my lathe or myself. Any advice?

 

[Tazmaniandevil]

It will do no damage to your lathe, it is slightly harder on the tools, but it will not do any long term damage.
Getting the resin to fully fill the crack with no voids etc. is not as easy as it sounds. There are all sorts of methods using pressure, and vacuum to force the resin into the gaps, all of which cost.

There are many folks on here who use resins extensively, and I believe it is a difficult area to master, but easy when you know how.
Keep us updated though. I have resin and metal powders, but have had few successes with them. I'm always interested to see what methods other use.

 

[Phil Pascoe]

I'm just about to do some research on metal powders before I spend too much, I'll see where this thread goes. I'm not interested in cracks that large, only small ones so it won't be quite so cost prohibitive.

 

[KimG]

While you can fill a crack with resin and have it be successful, you do need to be wary, if the crack has any form of rot, (usually this presents itself as a dark, soft material in the crack, then it might not be safe as the resin would not properly bond to the strong wood, and during turning the piece could fly apart. If the crack is as a result of drying (usually you can identify this by the fact that some fibres of the wood will bridge the gap, usually in a diagonal fashion) then resin will be a good and safe option, I usually mix up more than I need and just dribble it into the gap till it's over full, then leave it face up to set.

With cracks formed by rot you could try cleaning the soft stuff out and then adding the resin, or if the rot is pretty thin, use CA glue instead followed by resin, the CA will harden the soft stuff and the resin will bond to that.

 

[Phil Pascoe]

I'm thinking of smaller stuff than the OP - drying cracks in pippy oak and the like, so mine'll be simpler. I might think about dichroic glass insets for larger ones, as I have a small kiln.

 

[KimG]

Sounds colourful Phil, but how will you A: prevent the wood from burning in the kiln and B: get a flat finish, I imagine glass, even dichroic glass, would be a bit tricky in a lathe?

 

[Phil Pascoe]

Take a silicone mould of the crack, then make a plaster mould from the silicone. The glass would be stuck into the finished item and would be round edged proud of the wood's surface.

 

[KimG]

Intriguing, do post a pic or two up if you get round to it, I for one would be very interested in seeing that, it sounds most exotic!

 

[user 466]

I have often thought of having a go at filling some voids with resin but I am not sure which resin I should purchase. Should I use epoxy or polyester resin? There seems to be a huge variety of each and I find it quite confusing. Would someone please point me in the right direction.

Many thanks

 

[KimG]

I use epoxy resin, it works OK for me.

 

[Dalboy]

If you go with Epoxy resin (The glue type) start as you would when filling any void and that is to remove any loose bits. Once you have mixed the resin with any colour you chose to use put it into the void and with a hairdrier (just don't tell the missus) warm it you will find that it becomes very runny and will get into the void a lot better. At the same time be aware that the heat wil also make it harden quicker. So you need to find a happy medium. You also may find that it might require a second application so get theat mixed straight away and get it in on top before the first fully cures.

 

[user 466]

Thanks for the replies. Are we talking the Araldite type of epoxy here or something like the West systems products?

 

[KimG]

I use this stuff Steve, Chas recommended it, it's very good.

ZAP Z-Poxy 30 Minute 8 oz PT39 Pacer Epoxy, you can get it on ebay for about £12 - £13

 

[Phil Pascoe]

Why the 30m rather than the 5m? Just open time or another reason?

 

[KimG]

just depends on how much you have to fill I guess, for small fills araldite does just as well.