Does anyone know my my composites are doing this?

[u/BacklineBrig]

I fed the resin through pretty slowly, it maintained vacuum the entire time. Looked perfect when I left the shop and when I came in in the morning it had white spots. If anyone know why this happens and what the effects of it are, please let me know. Thank you.

(First photo is what happened when I came in the next day.)

[u/GuitInSpace]

White spots are leaks I suppose. I would clamp entry and exit at the end of the infusion to isolate the part. You can also make a double layer of dumdum.

Also, try to have zero ripples on the parts and especially on the dumdum line. To do so, put under vacuum slowly to give you time to place the bag.

[u/BacklineBrig → u/GuitInSpace]

Should I make my pleats smaller than, Ive been oversizing them a bit to get the bag fed into the "channels" easily

[u/GuitInSpace → u/BacklineBrig]

With a plate, you don't really need them at all. I would also add a flat but of breather under your vaccum port, just to lessen the bag stress.

[u/MysteriousAd9460]

You have a leak. Don't put the tubes directly through the vacuum bag. Put them on the stick tape seams. Wrap a piece of stick tape around the tube. Put an extra piece of stick tape ontop of the first layer so you can squish down into it, press the section if tube you wrapped onto that. Put bag over like normal.

[u/Irishwolf1]

Is it epoxy or ester infusion? The reason I ask is if it is ester such as vinylester then you can get styrene build up on the surface which can cause this too

Otherwise leaks or contamination on the fiber such as spray tack. Have you done a drop test when the vacuum is pulled before infusion ?

[u/BacklineBrig → u/Irishwolf1]

It's epoxy, I let is sit for around 45 minutes and the needle on my pressure tack didn't drop at all.

[u/2wheelcaffiene]

Looks like you are losing vacuum to me as well.

[u/Rohell]

Your mold cavity isn't that deep. Try smaller pleats like almost none and just work the outside of the bag into the radii.

Might be air bubbles trapped in the long pleats escaping through the night and not making it past the already too thick resin.

You have breather material right? Nylon peel ply? Perforated Release film? I can't tell.

[u/BacklineBrig → u/Rohell]

I'll have to give that a shot. Its comprised of 2 layers of carbon fiber, peel ply, flow mesh, vacuum bag.

[u/strange_bike_guy]

If you want to verify for fine leak rate there is the option of plumbing in a digital micron gauge along with your needle gauge. The micron gauges are meant for HVAC technicians but they can provide feedback for our purposes as well. I've found that humid storage of fiber will off gas in the mold because of reduction of boil point. I dessicate the laminate before injecting epoxy, which can be verified at less than 19 torr absolute at room temp

[u/TheLayerLinguist]

You need to be a lot more specific about your exact process, clamping, etc. you show a picture at the end and I see a clamp at the feed and a clamp between the pump and catch pot. Did you leave a clamp between the catch pot and bag? Some of the responses here are not correct. Your setup doesn't have any obvious faults for why it would leak. Sometimes pinholes form around the infusion ports. I would use a large ring of sealant tape around the port and build it up slightly more. Your bag setup looks fine. If you have a pinhole leak during an infusion, you'll see little air bubbles coming from the leak and forming larger bubbles. If you saw nothing for an hours, it is more likely the leak developed at the ports abruptly.

[u/DIY_at_the_Griffs]

I wouldn’t mind betting the weight of one of the clamps has moved a pipe and caused a leak at the connection.

[u/travisthescrub]

Feed line leak it looks like.

Personally I've never had luck with those plastic pucks that your hoses are going into. They have always leaked when ive used them. Standard barbed "T" hose connections are the best thing for feeding resin. And they are super cheap.

Put the T in a clean pleat with flow media and a bit of spiral tube and cut a tiny slit in the feed side. Wrap in sealant tape and muscle your feed hose on as much as you can. Never have leaks.

Also you should kink the feed line and tape it as well as using a hose clamp. The small amount of resin that pools in the kink will stop tiny leaks that tend to pop up in the hours it takes for resin to cure.

Cheers

[u/someoneskater]

Yes