bubbles....

[JPembleton]

I've put epoxy tips on a couple of my paddles and I noticed quite a bit of bubbling. I'm pretty sure this is normal and think I can get rid of the bubbles when I sand and shape the tip.

My question is more on glassing the blade and the amount of bubbles to expect, how to reduce the bubbling and what to do with the bubbles that appear?

Will a second application of epoxy be required (w/ 2.3 oz fiberglass cloth) under normal circumstances and is a light sanding required to get rid of any bubbles that may appear?

Jamie

 

[pklonowski]

Bubbles are not good. Can you post pictures? That'll make it much easier to figure out why it's bubbling, and then we can discuss how to repair/avoid it.

 

[JPembleton]

I assume the bubbles are created when I mixed the 2 part epoxy together and added the sawdust. I can work on a picture later today.

Jamie

 

[pklonowski]

If they are bubbles from mixing the epoxy, you need to be less vigourous about mixing. Slow down! Add the sawdust in small increments, scattering it in sparsely over the epoxy, and mixing it in -- again,
s-l-o-w-l-y.

You can also warm the resin & hardener in a pan of hot water (check manufacturer's specs; I think West System says 104degreesF, others may differ), before mixing. This makes the mixed slop runnier, so the bubbles can escape more easily. It also encourages the epoxy to start curing quicker, so you lose working time... but it gets bubbles out.

You can guess how I know this....

 

[Douglas Ingram]

You can also mix the sawdust into the resin first, then let it sit quite awhile for the bubbles to off gas, then mix in the hardener. Sawdust holds a LOT of air.

 

[JPembleton]

Thanks Guys,

The bubbles on the epoxy tip came off as I hoped they would when I cleaned up the tip with a belt sander to shape it.

I will admit to the mistake of creating most of the bubbles buy likely stirring too fast. The next time I mix some up i'll take it slow to see what happens.

I like the idea of adding the sawdust in and letting it settle first before adding the hardener.


Jamie

 

[Splinter]

Vibration

If bubbles form while mixing, yes, you are mixing too fast. Once the container is mixed, you may have some success removing bubbles by briefly holding the container on a ROSander so the vibration brings the bubbles to the surface before pouring it out. Worked for me. Some of the more stubborn bubbles came to the surface but didn't pop. You can pop them with a toothpick yourself. Good Luck.