Infusion video

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#1

[ame=“http://www.youtube.com/watch?v=VodfQcrXpxc”]YouTube - How To Do Perfect Vacuum Resin Infusion of a Carbon Fibre (Fiber) Part - Basic Tutorial[/ame]

I only spoted two things he did incorrectly:

clamping off the resin inlet line on the wrong end of that line ( should have been clamped off close to the resin cup).

He then at the end of the infusion clamped off the vacuum line and shut down the vac pump… a very bad idea. Let that pump run until the part is fully cured and don’t clamp the vac line.

Good instructional video otherwise.

#2

Why should you let the pump run until the part is cured? I was under the impression that if it was completely sealed and you clamp the vac line it’ll stay under the same pressure?

#3

Wow that’s good timing, I was watching this video only last night because from what I have read resin infusion may be the answer to a few of the problems I have been experiencing so far.

I too was a little confused by him clamping off the vacuum line only a few seconds after clamping the resin feed line. It seemed that there was still air being sucked out along with the resin when he clamped the line, surely you would want to wait until all air was expelled from the layup? When do the rest of you clamp off the vacuum line? do you leave it until the resin has fully cured?

The surface finish of the part in the video seemed perfect, could that be because he clamped the line off so early thus leaving the part slightly more resin rich than if he had of left the vacuum line open? I was under the impression that with resin infusion a clearcoat would need to be applied to the cured part because the the finish of the infused part would not be such a high gloss due to the fibres being in such close contact with the mould surface. Is this correct? I have much to learn :frowning: but I am enjoying it :slight_smile:

#4

doesn’t matter where the resin line is clamped. I ALWAYS do it as close to the part as possible. Everyone here does.
as for the vac…yeah, leave it on! It you get a leak somewhere somehow, even if it’s next to the vacuum line, alllll that air isn’t being sucked out! And yes, resin rich.
Also, for technical sake…the resin will not always equalize, meaning one side (resin) will be thick, and the other side (vacuum) will be thin. When you let the resin in your bag, that side is more or less at ATM pressure, while the vent side is at full vacuum. You want to clamp the resin side, and pull the resin through the part enough so the pressure differential isn’t that different.

#5

In a perfect world, yes. That is also how the universities usually do it. (no offence, but many teachers and studens think they live in a perfect world)
But how about that tiny fiber under your tape, a porous spot in the bag, a tiny leak. Only seldom when doing a drop test there is absolutely no leak. Many times there is a small leak. Too small to trace, but it is there…

Just leave the pump running, or have a pressure switch control the pump, so it runs as needed. (this also gives the advantage of being able to hear what is happening. As long as the pump does not run, there is no need to check. If the pump starts running more often, a leak has developed.

As for clamping of the resin line: I usually clamp near the product, but not too close. The weight of the clamp should not become a factor. I use very very small and lightweight clamps. (sort of nipple clamps… :)) A handful of clamps fit in the pocket of your pants.

#6

Ok. I didn’t realize it was alright to allow a 2 or 3ft tube full of air into the laminate; speaking of where the resin line gets clamped at.

has anyone ever tried infusing using a ply of lightweight fiberglass cloth in contact with the mold surface, then cf cloth. I was just curious if it would/could improve surface finish of the part?

#7

I clamp the resin and then the vacuum line once infusion is complete and turn my pump off with no problems and get great looking part.

#8

I’ve always infused parts with out clamping anything ever. I always turn my pump off as soon as the infusion ends and even when all the air rushes in I get perfect parts every single time. Even on those off chance occasions where I run out of resin and have to mix more.

But I live in a perfect world :).

Haha jk :P.

I wait till the part is well off into B stage before I turn off the pump.

#9

I’ve been extremely lucky sometimes where I’ve introduced a leak into my bag and the whole part fills with air, yet the part comes out clean. It’s only happened a few times though.

#10

I too also clamp the hose and turn the vac off and have never had a problem.

#11

First time I have seen this video, his way obviously works but we do it different…we crimp the feed line right at the resin infeed pot, we simply fold the line while the end is still in the pot so no air is introduced. Secondly, we never, ever clamp off the vacuum, we leave it running for 10 hours on a timer, clamping that off doesn’t make sense to me. A lot of peoples moulds are porous on the back side and air can leak through the mould from the reverse side unless they bag the whole mould.

Couple of other things, why he is letting the resin run into the catch pot? We clamp off the resin infeed well before it reaches the line, I can understand doubling up the flow media at the infeed, but unless my eyes are playing tricks he had the flow media also doubled up by the vac line.

#12

I should re-run the video, but indeed, wasting epoxy by entering it into the catchpot is a shame, especially on such a small object.

When we do large objects (boats) it sometimes cannot be avoided to spill some resin, but the fun is to infuse without spilling a drip of resin. (although I always like a small left-over in the resin pot)

#13

Just take a look at the air bubbles in the flow media when the part is cured.

#14

I have been turning off the pump once the infusion is complete and it caught me out once or twice, to come back to an infusion the next morning to find theres no vacuum and the part is ruined sucks, but i do worry about leaving a pump on overnight.
it gets pretty warm after a while, here is the pump i’m using http://www.dosivac.com.ar/serie-dvr.html their website is in spanish, it’s seems to be a good quality pump (DVR 140)
should i be worried?:confused:

#15

It is normal that your pump becomes hot, dont worry. If mine is runnin a few hours you can not touch it.

#16

I wouldn’t worry much, they will be hot to the touch when running that long…

#17

Make sure u top oil up :slight_smile:

#18

Thats what she said :).

#19

I was under the same impression until I stood back and said, "What the hell!?*.

I usually leave the pump on until the part is hard enough to not allow air to get in, and will not beef up.

#20

I like how he put a wooden frame around the mold. Makes it easy to work with :).