Hey guys, do you know what can be the reason of small opened holes in laminate after infusion process?
It become when I dont use gelcoat, I look at part from 20centimeters and I cant see it but when I look very close I can see randomly-stated and opened little holes, they are so small as I could say they are rather points than holes…
What can cause that? , I heard it might be something about “to good” vacuum? I always pull -1 and let the laminate suck some more resin before clamping feed line.
These are pin holes, the bane of all carbon fiber manufacturing. infusion is generally the best way to get around it. it sounds like you need to degas your resin as the pin holes you’re getting are from small air bubbles within the flow of your resin that are ‘too deep’ inside the stack to get out - meaning they were introduced late. are you degassing?
Yes Im degassing 15 minutes, so its quiet long time
Without a picture we can’t tell. Spray some clear 2k over the part, that’s a good way to determine or it are (pin)holes. How long do you lett your mould under vac before infusion ? Did you try do slower your flow ?
I think pictures wont show it as these are very little points, I vac bag about 20 min before infusing. I didnt slower the flow. I somewhere heard it might be connected with effect of cavitation ? but honestly i dont know much about this
I dont want to use clear for some parts
If your resin is degassed correct and your brake zone is big enough than it will be the cappilary action. We showed this effect in the MTI animation video. Maybe this will help to understand what happens.
SO basicly how to fight against this effect of cappilary ?
I de-gas hardener and resin separately for 30 minutes. Then I mix and degas for another 30 minutes. At least.
Two possibilities, use MTI hose because thats one of the points why we developed it or you have to create a brake zone that you will have a more or less pressure equalent system after infusion. But Possibility two is not as easy as it sounds.
Im not persuade to MTI as long as it only suck out air, so the same job as vacuum pump with catchpot , what does it have to cappilary effect?
It is explained in the MTI thread and also in the animation. It is not the same as resin trap. You can not suck out resin, so the resin can not ravel by caplillary effects out of the part.
Can someone send me a little shred of this MTI? I tested so many things that this is rather last option, despite that I dont know why Im not very hopefull…I simply cant imagine a one simple hose could resolve all infusion problems, better Im wrong.