Hi all, 

After a whole lot of research and watching many tutorials from Easy composites I finally thought I'd have a go at resin infusion.

I've dabbled a little previously with some composite aircraft repairs whilst in the RAF, but have never done anything like a cosmetic part.

The issue I have is that there are voids across the surface of the part, it was quite a complex mould shape ( Lotus Evora GT2 Air box, which was designed for pre-preg and not infusion) but I thought I'd have a go anyway. 

As this was just a practice infusion I used 'Black Stuff' 200gr fabric as the outer layer, backed with 3 layers of 420gr twill. Next time this mould is used will be with pre-preg, but I'd just like to understand the possible issues with the surface here initially.

Other factors - Compound curves and vertical walls required fusion fix - Resin not fully degassed? (Degassing Pot hasn't arrived yet, although left for 10 mins) - Resin flow speed too high? Should have started with something much easier?

That doesn't look too bad for a first hit at all!!

Could be a few issues like minor air leak, infusing too quick, leaving pump running with inadequate resin barrier, etc.
The corners look good so I suspect very little if any bridging which is good for such a complex shape. 

In essence you may just need a bit more resin in the laminate.  If you leave the resin feed open for an extra 30 seconds to a minute after clamping the vacuum line then you should have plenty of resin in the part.



Warren Penalver
Easy Composites / Carbon Mods - Technical Support Assistant

I agree with what Warren suggests but wonder what release system you're using?  Sometimes the release or spray glue will leave surface issues...

Are you envelope bagging or bagging it down to a vacuum-tight table?  I'd suggest this if you have a table that will work (release coat first!) - if you leave a peel ply resin break over the edge of your mold and run some 50mm or so wide strips of peel ply down the outside of the mold and onto the table, you can just put your vacuum line in contact with that peel ply and you'll have an awesome resin-break.  For something that size, some strips of flow-mesh around the perimeter of the mold on the table will be plenty of manifold - resin should never make it much past the edge of the part - let alone down to the table top.  Leave your pump on until the resin gels - especially with a big block like that under vacuum - too many variables!

I wrote a post about this that people seem to find helpful:  https://explorecomposites.com/2019/11/19/troubleshooting-vacuum-infusion/