Talk Composites - The Forum for Advanced Composites

Imperfections in final piece

http://www.talkcomposites.com/Topic22213.aspx

By Shane1985 - 11/6/2016 7:26:58 PM

Hi Guys,

After much blood sweat, tears and not giving up, I finally managed to make a Carbon Part which I am half happy with.

The only problem is I am finding holes in the cure resin, pin holes and air bubbles as pictured below.

I used fast hardener with the usual Epoxy as its only a small piece and allowed for it to degas for 15 minutes after stirring it thoroughly. I ran the infusion through and made sure that the epoxy being pulled through the catch pot side came though for a good while so any aired epoxy was removed. 

Then clamped off the feed line the the the catch line.

Last night was very cold probably about 1 degree but I had the heater in the shed, however when I got checked this morning the heater failed and I had to bring the part to finish curing this morning in front of a heater.

Once I demoulded I found the holes and air bubbles.

Any Help on how I can prevent this please? Its the second time this has happened. 

http://www.talkcomposites.com/Uploads/Images/cc51a0b8-fb19-4bf0-9735-0931.JPGhttp://www.talkcomposites.com/Uploads/Images/7df93709-bd1c-42db-a41e-5698.JPGhttp://www.talkcomposites.com/Uploads/Images/3fd27edf-2b0d-4ac7-8c9b-97d2.JPG




 
By Chris Smith - 11/10/2016 10:34:55 PM

I also had this problem. After talking to warren we found out the vacuum pump wasn't strong enough and/or the resin is going in too fast. Try clamping the resin side and slow the feed a little. These are the problems I found and after doing all the above I pulled a perfect part. Good luck.