Vacum Bag Resin Infusion?

[emans4seam]

To my fellow board builders or those interested,

Has any one attempted the vacum bag resin infusion method? I was reading about the Dark Arts project featured on Stab In the Dark as well as seeing a youtube video from "Rock and Sea Garage Board Shop" about building a carbon fiber board and it really piqued my interest. After digging into the proccess I was really interested about trying this myself (if cost allows).

But I have a couple questions for those that may have tried;
1. How would you run the tubes that the resin runs through to prevent possibly denting the foam from the pressure?
2. How do you keep the CF in place on the top and bottom? would you have to glass seperately or maybe put down a super light epoxy layer for the CF to stick to?

 

[need 4 speed]

Piqued

 

[emans4seam]

Piqued

Yeah, noticed that after I hit post...

 

[need 4 speed]

Only a handful of actual board builders here,might try Sway

 

[emans4seam]

Only a handful of actual board builders here,might try Sway

I can see where the turn off can come from. It is definetly not as cheap or simple as traditional glassing.

 

[need 4 speed]

@GromsDad
@oneula
are a couple
@ghostshaper

 

[Clamsmasher]

Hey man,

I did a foil board by infusion and have done a couple of other little things too. Overall the board wasn't a win but I learnt enough that I think I could pull it off next time.

For starters, I would probably stick to a poly blank. It will withstand the high vacuum pressure better than EPS. If you seal it first the resin will wet the fibre out a bit quicker.

Next time I will avoid using the tubing inside the bag. I certainly does cause denting. I would use two separate lines for resin input and 2 for vacuum. Use PTFE ports inside the bag probably on the stringer to help with support. Use flow media...put one vacuum line at nose and tail and the resin lines dead centre of deck and bottom. You have to keep a close eye on the progress and close off each vacuum port as the resin reaches it.

The actual glassing was the coolest aspect of infusion for me. You can do a whole board, very complicated layup before it ever gets wet. Use Super 77 to tack down the layup. No need to be stingy, epoxy doesn't mind this stuff. You really have to get the slack out of the fabric otherwise it will wrinkle on the rail edges.

I hope this helps.

 

[Clamsmasher]

Oh, and make damn sure the bag is sealed perfectly. If any resin gets into the vac lines, and it does....it will block them when it cures giving you no control over the inside of the bag. If it leaks that is basically mission blown.

 

[oneula]

you don't really need to go the whole infusion route although it's the best and used in most high end industrial epoxy setups for carbon parts etc.
There's all kinds of disposables you need

You can get a similar deal by using an appropriate resin proof peel ply flow thru layer and absorber on top of that which will let you press the excess resin out of the cloth. The hard part of bagging cloth is preventing wrinkles and that's why they use the spray tack to keep the cloth smooth and held down during the process. Then you pull the peel ply off and the excess resin will be captured in the absorbent layer on the outside. Just make sure your bag is resin proof. My composite sensei Charlie (BB30 on Sways) does it all the time with his epoxy builds and gets a good resin to cloth ratio as close to 1:1 as possible. A slow cure resin is also important. Be interesting if someone comes up an absorbent layer made of the same stuff as those absorbent diapers to help suck out the resin through the peel ply under vac pressure.

Never bagged carbon, but I have bagged blue texalium from FBH which is also a bitch like carbon
Also if you use those eco cloths like bamboo jersey, flax, wool, banana fiber its best to bag on the cloth so you can squeeze out all the excess resin. I hand lammed the bamboo jersey from Greenlight decades ago and it wasn't fun although Brian at Greenlight had no issues.

You know, you don't need to use carbon, there's lots of other materials that have the same impact that are less expensive. Bamboo for one. For anything related to bagging I would defer to Gary Young who pretty much invented the process for surfboards like 30-40 years ago. He still makes them on the big island. http://woodensurfboardshawaii.com/surfboards/

 

[Swiftvelo]

If you could figure out a resin transfer method that would be better. Skim boards and fins are done this way. Coming from the bike world and carbon fiber, the excess resin is the problem. That’s what creates weak spots. A properly glass board is still the best for the cost. There’s other options but the foam core is limiting it.

 

[npsp]

I think Senor Sopa builds his boards this way.

 

[GromsDad]

Infusion is better suited to making parts in a mold like is done in boat building.

Vacuum bagging on the other hand has a place in board building for the backyard scientist. I'm intrigued by it and have read up on it quite a bit. If you dig through Swaylocks there is a thread by Bert Burger who outlines a process an ambitious home board builder could use to make nearly indestructible and very light boards.

The thing that interests be the most is the use of prepreg carbon fiber and glass. I have a cousin who has a company making high tech carbon fiber parts and everything he does is prepreg cured under a vacuum. The process is really cool. In surfboards this would be the method used to make something similar to the Aviso hollow carbon fiber boards.

Going back to the OP's original questions:

1. No idea on that one.
2. Spray adhesive.

Lot of good info on this youTube channel and others like it: https://www.youtube.com/user/easycompositestv/videos

 

[emans4seam]

1. No idea on that one.
2. Spray adhesive.

Lot of good info on this youTube channel and others like it: https://www.youtube.com/user/easycompositestv/videos

Spray adhesive, didn't think of that one.

 

[emans4seam]

Thanks to everyone who commented, it was really just an interest I had. I recently gained access to a vacum pump through work and was wondering if it was realistic.

 

[emans4seam]

you don't really need to go the whole infusion route although it's the best and used in most high end industrial epoxy setups for carbon parts etc.
There's all kinds of disposables you need

Never bagged carbon, but I have bagged blue texalium from FBH which is also a bitch like carbon
Also if you use those eco cloths like bamboo jersey, flax, wool, banana fiber its best to bag on the cloth so you can squeeze out all the excess resin. I hand lammed the bamboo jersey from Greenlight decades ago and it wasn't fun although Brian at Greenlight had no issues.

I will definetly have to look into those alternative options. I like the idea of trying something other than the traditional glass.

 

[emans4seam]

Next time I will avoid using the tubing inside the bag. I certainly does cause denting. I would use two separate lines for resin input and 2 for vacuum. Use PTFE ports inside the bag probably on the stringer to help with support. Use flow media...put one vacuum line at nose and tail and the resin lines dead centre of deck and bottom. You have to keep a close eye on the progress and close off each vacuum port as the resin reaches it.

The actual glassing was the coolest aspect of infusion for me. You can do a whole board, very complicated layup before it ever gets wet. Use Super 77 to tack down the layup. No need to be stingy, epoxy doesn't mind this stuff. You really have to get the slack out of the fabric otherwise it will wrinkle on the rail edges.

So this was interesting because from what I have read is that a full carbon wrap done correctly has some crazy fun flex characteristics so I was considering going for a stringerless board. I will have to find out if there is a way to avoid a stringer without damaging the board. Might have to make some carbon fiber hand boards to test...

 

[Clamsmasher]

You absolutely don't need a stringer, I think most of these high end composite build go without. One issue that adds to the complexity of vaccum having that I forgot to mention..... You need to use a rocker table to stop the bag from twisting/bending the blank out of shape.

 

[ghostshaper]

Or some tip that Stretch said:
hand lam the rails w/ fiberglass tape first, then you don't need a rocker table.

Also, regular vac bagging a hand lam would be the first step before jumping into infusion.

 

[Senor Sopa]

I think Senor Sopa builds his boards this way.

Just the bagging part. For one layer of cloth, I don't think infusion is the way to go. It it was 10 ply...

Oneula is correct, just lam it and put the peel-ply on and some breather in the bag. You will get a VERY ligh lamination.

I make the bottom and deck skins on a table and then apply them to the board with the vacuum. A skin being 4oz cloth and 1/16" bamboo.

 

[GromsDad]

If I had the extra space I would make myself an adjustable rocker table so I could dabble with the vac bag process. Bert Burger's process has always been something I have wanted to play with. If you are unaware, here is a breakdown of the process in pdf form. Worth reading:

https://swaylocks7stage.s3.us-east-2.amazonaws.com/s3fs-public/Bert Burger Vacuum Forming & Sandwich Construction Thesisl.pdf

https://swaylocks7stage.s3.us-east-2.amazonaws.com/s3fs-public/Bert%20Burger%20Portfolio.pdf