Ive cut a name into a piece of pine, and then filled the void with coloured resin.
On first application, it all looked good :
But after about an hour, it bubbled up all round the edges :
Ive resigned to this now being scrap.
Anyone know why this is happening? Should i have sealed the edges proir to the resin?
You hit the nail on the head, the wood needs to be sealed. Of course different woods are different in how easily the absorb resin and paint.
Ok thanks - is varnish suitable ?
Any kind of clear finish fully dried should work.
This also could be caused by either:
- The air that is injected into the resin during the pour. Heat with a torch after the pour to remove the air.
- The displacement of air into the end grain of the wood. Precoat the cut-out area.
I would create a small and simple sample for testing these theories…
The best way to prevent unwanted air bubbles is to seal the wood before you cover the plastic. And I think a glue brush would be a good choice.
Hey @MikeMeyer, since you’ve done a bit of this, do you have some tips to share?
Shane did a couple of presentations for the SDFWA and shared lots of handy details. Here’s his own video. Shane started doing CNC work and then working with epoxy after he tore a shoulder and had surgery and couldn’t work for months. He excelled at the techniques as you will see. Also, I don’t use V-Carve or any of the software these guys talk about and you are the same just look for the techniques and get a beer when they go on about finding a setting or lots of Vectrics type stuff.
And here’s a video where he presented at SDFWA:
Brilliant- I will watch those before i attempt again. Thanks
Yeah, I would add that air is introduced into the epoxy when it is mixed too vigorously; better to mix longer, slower. Let the epoxy rest for a couple of minutes after mixing to degas and dust it with a torch prior to pouring. And do all of the above (I use cut Spar Varnish to seal). My experience has been that once the pour is completed, stick around for 10 minutes or so with your torch and lightly dust away any remaining bubbles.
And I would add that the work piece shown is salvageable. Once the epoxy has completely dried, it machines very easily. You could stage sand (120,220,320 etc.) or plane it and then polish it.