Thread: Preventing epoxy from leaking

If I am using liquid epoxy to fill a crack I will go to the opposite side & stuff in some shavings and / or sawdust followed by cyanoacrylate - CA glue. That will set up in a matter of minutes, then turn over and run in epoxy. I don't do colored casts of epoxy, but will pack in coffee grounds & epoxy, alternately until full.

I don't try to disguise a crack but use a contrasting filler, usually fine sanding dust or shavings from under the lathe. Also coffee grounds and instant coffee. As a binder / glue I have used CA, epoxy, and wood glue. All work but wood glue takes overnight or days to dry. CA is the fastest.

Thanks Paul39, I will give that a crack tonight. Adrian

Originally Posted by Adrian Lloyd

Hi, I’m new to turning and have started to experiment using epoxy at this stage it’s only to fill cracks in the timber. I was looking for the easiest option, taping up the block of wood with different types of tape but nothing so far has sealed and the epoxy flows out. Is there a tape sufficient for this purpose or do I need to make a mould and what do I make the mould out of, any tricks I need to be aware of.

Couple of tips.
Use LOTS of tape at least 25 mm either side of cracks.
Gently warm the wood either side of the cracks with a hot air gun - on hot days I just put the wood in the sun for an hour or so
After applying the tape, warm it slightly with a hot air gun and rub teh tape to force it onto the wood. If possible use a clamp with a softish plastic ends and clamp the tape hard onto the cracks.
Don't try to completely fill deep/through cracks in one go - add enough epoxy till you see it on the other side the let that dry and come back a [second time to fill it up.

Ive used lots of different tapes and usually get away with plain masking tape but make sure it's fresh tape. On problematic pieces I've used Gaffer tape.

I've also used Plasticine or window putty to block the reverse side. Usually with tape over it for added security.

I only do this for wide cracks and when there's a lot of material to remove on the putty side, as there's no guarantee of removing all the putty... and sometimes there's a reaction between the putty & epoxy that seems to make the epoxy more granular. So I allow for turning that section away.

As BobL said above, a few small pours is the best idea. That way you don't lose as much if it does leak and the first pour will often seal or limit any small leaks so following pours are contained.

I don't know about epoxy, but when I was looking for a tape that wouldn't let go when I was filling cracks with CA, I found 'All weather tape' works a treat - CA seems to dissolve the adhesive on all the others - might be worth trying with the epoxy

I’ve also used blutack with mixed success.

On thick slabs I've found filling large holes or cracks on the underside of the slab with builders bog works very well. easy to work with and you can fill large areas quite quickly.

I had a middle of the night further thought: Use wood glue and strips of newspaper, smooth down tightly to timber, smear glue on outside, let dry thoroughly, maybe even a second layer.

Thanks everyone for your advice, I will follow up with several and probably a combination of the suggestions.

glad wrap. then tape it up as best you can.