Video - Can someone tell me when to stop the infusion? (2 minutes long)

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#1

Hi Composites Experts,

You might remember me earlier from my first infusion video posted not to long ago. I tried my second infusion and am now unsure on when to stop feeding resin into my part.

In the video you will see that the resin flows across my part fairly quickly. Then it appears that later on dark spots will form, which will eventually lead to a whole dark blanket of resin covering my part until it is dark; at which point i stop feeding it resin.

When do I stop the resin inlet? When the initial resin flows across my part (in this video only takes about a minute) or when the whole part is dark?

I also appreciate any other advice that can be offered.

Please watch the Video on Youtubes Website, so that you can see my annotations. You can get to the Youtube website by clicking the title link on the video below.

[ame=“http://www.youtube.com/watch?v=E5Jk0I7pK6Q”]Infusion Questions - Composite Dive Fin - YouTube[/ame]

Youtube Link:

http://www.youtube.com/watch?v=E5Jk0I7pK6Q

#2

I think the mesh you use is too fast for the laminate. You see the mesh is infused quite rapidly, but the underlying laminate (the carbon fin) takes a lot longer.

I would:
-change mesh to something slower
-change perforated film. What kind of film do you use now? It seems the perforations are quite small. If you have the chance, use MP22 perforation.

#3

two things i would do diffent.
first everything looks plumbed right except you need to tie the vacuum line to the laminate with peel ply [not perf ] that will eliminate the excess resin problem,. Second far as resin racing across way to fast you can put your resin pot on the floor and pinch the resin line almost shut so the resin doesnt race . Try to get a ‘narrow’ resin front, 3cm-5cm or smaller. that will be from very front edge of resin to the very rear edge where bubbles stop.you had guessing a8 inch, 20cm lag

#4

ack!!! number ONE: You have your vacuum line completely cut off from your part!!! You NEED something from your part to your vent spiral!!! Use that same gap distance, but put peel ply to the vent. Else you are relying only on wrinkles to carry the vacuum that draws the resin through.

Also as others have said: Switch to a slower flow media, use a more perforated release film, and you can cut the flow media SMALLer than the part on the sides, and vent side…maybe by 1". Depending on your fabric and gel time, you can change that distance.
Another thing you can try is, clamp the tube slightly, so the flow is not that great. Your flow media doesn’t HAVE to change, but if you change how fast the resin flows in, it will allow the fabric to wet out.

#5

Thank you everyone, these are all really useful tips. I have been learning how to do infusion solely off of this forum and I really appreciate the help everyone offers.

I am using release film and peel ply. The release film does have very tiny holes in it, I purchased it from US Composites. Do you think it would be better for me to just not use the release film at all, and just use the peel ply?

I had a really hard time finding the mesh which I currently use, so I am unsure if I can source a slower mesh. Unless someone knows a good source where i can purchase a few yards for a decent price. I live in Hawaii and most places want to charge me $50 shipping just for 2 yards of mesh.

#6

Personally I never use release film in a infusion, only peel ply.
Like Riff said you can reduce your intake tube to reduce the resin flow. If you really want a slower mesh I use Enkaflow.
http://www.fibreglast.com/product/EnkaFusion_Nylon_Matting_Roll_1401/Vacuum_Bagging_Vacuum_Infusion

If you look at the pattern in the pic on Fibreglast you can see the resin will flow fast if it’s traveling vertical in the picture and it will flow slow if it’s flowing horizontal in the pic. So you can get two speeds out of one media, plus with playing with intake size you can really tune the flow speed.

Infusions can be done a thousand ways and this is just one of the ways that works best for me.

If your a new customer you can sign up for their email list and they will send you a email instantly with a code for 10% off and about every other month you get a code for 20-25% off your order. Yes they are expensive though!

#7

Tiny holes? That is P3 perforation, suitable for wet bagging, but not infusion. You can do without, but removing consumables will be a pig. Especially with those thin laminates you make.

#8

The way I would do this is by keeping the green flow media, replacing the perf release film with peel ply, and cutting the flow media short about 20%. The resin will slow down after it reaches the end of the flow media and give more time for the air to evacuate. I would let the peel ply go all the way towards the spiral tubing.