Hey everyone,

I have been infusing parts using a two mould method to reproduce a curved piece with smooth surfaces on both sides. Unfortunately, during my infusion, once the epoxy reaches the vacuum line side and it starts spurting bubbles into the catch pot (see the middle-right circle), small bubbles started to climb back up the resin line, which is connected to the resin feed pot (see bottom circle). I can't seem to get it to stop. During my first infusion of this part it did not have any adverse effects, but it still concerns me that air is:

a) apparently not all the air is moving towards the flow of vacuum - ie. towards the vacuum pump
b) there shouldn't be bubbles in there regardless. The only bubbles I could think of are ones that get mixed in with the epoxy and do not have a chance to off-gas out of the mixture before they are sucked into the part. I realized that a degassing chamber would help fix this, so I am going to build one.



And yes I just realized that you can't read the print so ignore that part of the picture haha.

Anyways, if anyone else has experience this, or knows what it may be, that would be a big help. It is unfortunate that it is a closed mould, as I cannot see the details of where these bubbles are coming from. Any help would be greatly appreciated.

-Mike-

as far as procedure goes:

a) pull 28inHg on closed mould
b) prepare epoxy in resin pot
c) unclamp and allow resin to flow through laminate
d) top up resin pot as required
e) wait 45 minutes for epoxy to reach vacuum side
f) AS SOON as resin burbles up vacuum line, close resin feed line
g) keep vacuum on laminate until cured.

It has seemed to work well for me so far, but if there are some crucial steps I am missing, please let me know.

-Mike-

Hi Mike

Make sure your mold is warm and the resin is warm. If you have a perfectly sealed vacuum on your mold.(do the vac drop test before you infuse)

If so, let the resin flow out of your part to your catch pot. Let most of what ever you have left in your resin feed pot flow through. I believe this gives you a better chance of flushing out more air bubbles.  Now clamp off your vacuum line close to your mold. Wait 15 seconds before you clamp off your resin feed line. I believe this will allow your laminate resin pressure to equalize getting rid of vacuum voids or what are called pin holes. As you wait that 15 seconds you will see more resin being drawn into the mold then clamp it off close to the mold. Shut your pump off and let it cure.

This has worked for me. If you try this let me know how you make out.

Fred