Infusion resin specs and wet lay vacuum bagging

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#1

When comparing infusion epoxy specs to normal laminating epoxy I was surprised to see that the infusion resin looks better even before post cure. Looking primarily at the strengths, and elongation. I was under the impression that you gave up some strength / stiffness when going to the lower viscosity.

For some time we have been using a thick 900cps resin for wet lay vacuum bagging. We switched to the 900 from a 600 because of the better properties. It would be worth the extra cost if we could get even better properties from a thinner infusion resin. Would there be any problem with using a infusion resin with wet lay vacuum bagging? I have been practicing infusion but it may not be right for all of our parts.

Does anyone have a suggestion for epoxy infusion resin in the US in single gallon quantities? So far I am looking at MAS, adtech, pro set, and composite envisions. Composite envisions will not publish the strengths / elongation so they are last on the list.

We are building 30’ long 15" wide racing hulls. Typical layup is 3mm foam sandwiched between 5oz carbon.

#2

There are some down and upsides for a low viscosity for wet layup vacuum. What kind off better properties do you think to get with the other resin ? The resin determines only < 1 % off the strenght of a carbon part.

#3

I use PTM&W infusion resin for some wet lay-ups , it works much better for thicker and tight unidirectional fabrics and les pinholing on clear carbon surface finish
you can get it in gallon

http://www.ptm-w.com/ptm-w-products/epoxy-products/epoxy-n-fusion-products/epoxy-n-fusion-products.html

#4

Depending on the resin, I’ve found wet layup can be a bit more difficult using infusion viscosity resin. For one, you don’t get as much on your brush/roller, so you end up sort of slopping it on. Which isn’t great technique. It also doesn’t hold the plies together very well, which may or may not present itself as an issue for you depending on the complexity of your parts. Of course when you apply the vacuum everything gets pushed into place, but I always like to have things as neat as possible before bagging.

Realistically, these issues probably stem from my limited experience with wet lay, I normally do infusion myself. They also aren’t genuinely issues, more just annoyances. Personally I find wet lay a bit stressful, so I don’t like it when things don’t go to plan and work as I am used to.

#5

Infusion resin can also be controlled by temp. I usually infuse around 80-85 degrees since that’s what seems to be the happy medium with enough time before things kick and my infusion mesh I use for larger and small parts…

But sometimes I’m caught not hearing the room for long enough and my molds colder or resin is colder too and it’s thicker which takes more time. If you are set on using infusion epoxy then you can mess with the temputures to play with the viscosity. Just make sure to also alter the hardener you are using for desired reaction. Meaning if you usually use slow for a 60 min work time at 77 degrees or 70 but am planning to work in a 60 degree atmosphere I may choose the medium, or just heat things up afterwards.