Koenigsegg Agrera Prepreg Carbon Fiber Tube Bagging Process

General Composites Discussions Composites Talk
#1

Hey guys,

http://youtu.be/504I_hJDFck

Could anyone look at this video and explain how they are bagging this? Its a good video, but most of what I’m referring to begins around (3:45). They are bagging an engine manifold in a multipart mold and the technician brings the bagging material through the manifold (4:17). You later see the part bagged and it looks like they may even use 2 bags (4:42).

Also, he explains how they make curved tubing in a split mold and mentions that they bring the bagging material through the tube to pressurize from the inside (5:00). It looks like they are using preforated film, breather, & vacuum bag on a tube…no bladder.

The only explanation that I can think of is having both ends of the bag sealed to each other which would seem to equate to one helluva bagging experience. Anybody have any insight?

#2

You can use just one longer bag let slip inside the part and then fold it back onto the mould so that its two open edges can be sealed toghether, or just use to bags, one inside and the other outside with both open edges sealed togheter.

#3

Awesome…that’s exactly what I was looking for. I knew it had to be something simple, I just had no experience bagging a 2 part, closed, hollow mold. THANKS!!

#4

Hi Roberto
I’m a little confused about your explanation …
I don’t get it. Can you maybe give some more details about how you would make it work?
Thank you

#5

at 4:47 you can see where the first bag is connected to the second (tube) bag. Tht way you can make a vacbag tunnel trough a part.

#6

could this method be use for making a part with infusion process?

HOw would one be able to infuse from one end to the other and not have the resin drawn along the outside(non-reinforcement stack side of the mold)of the mold if the whole mold is enveloped in a tube bag that is folded back on itself?

#7

Hi sorry but I’m Looking again and again and 4;47 doesn’t show what I’m trying to understand
I’m breaking my head :).
The only way I can think about is if the inside tube is full of compressed air to push the laminate to the mold ( like a ballon inside the mold) and then all of it go inside a bag to be under vacuum
But if its this way then how the ballon react with the vacuum
Thanks

#8

If I’m understanding correctly… imagining a tube and an envelope bag in my scenario. Push the envelope through the inside of the tube like you were putting a trash bag in a trash can, then bring the excess over and around the tube to meet back at the bottom of the bag and seal the entire part. This is the way I infuse large tubes now. Same basic idea?

#9

Care to post any pictures of your product? Or better yet, a picture of the bagged product before infusion?

#10

I’m sorry, I don’t have any pictures from when I used this method.
But you’re almost there:

The inside tube isn’t full of compressed air(with a balloon), it’s full with normal atmospheric pressure. Vacuumbagging the laminate creates the pressure.

Here you can see the “tunnel”
Everything between those two bags will be sandwiched, with vacuum pressure.

I used this method to create front window frames :slight_smile:

Yes! But you can attach the tube to other structures in one go too like that, which happens here.

#11

Thank you
So In fact one bag will be inserted into the funnel and fold over to be able to close it with the tape
Into here no problem … Now we need to put vacuum to it to push the laminate from the inside and then will also push the 2 parts mold from the outside …if I understand well?
Now should all this be put into another bag to apply sure pressure to the outside of the 2 parts mold?

#12

yes, wou will be envelope bagging the whole mould, unless ofcourse you can get the mould airtight.

#13

Thank you
So it’s 2 bags
One for the funnel and the mold
And another one where you put everything inside?

#14

To steal the tube example:

2 part tube mould to lay up a tube in:
Layup the two halves, one flush, one with overlap,
place a tube bag in the halve with the overlap,
Close the moulds,
place bag around, and attach that bag to the inner tube,

Apply vacuum, and no you can see trough your tube :slight_smile:

This is a simple example, you can make the tube with complex curvature, and attach the tube to another part in one go.