Would I be better with Prepreg ?


Author
Message
Massimiliano
M
Supreme Being (1.3K reputation)Supreme Being (1.3K reputation)Supreme Being (1.3K reputation)Supreme Being (1.3K reputation)Supreme Being (1.3K reputation)Supreme Being (1.3K reputation)Supreme Being (1.3K reputation)Supreme Being (1.3K reputation)Supreme Being (1.3K reputation)
Group: Forum Members
Posts: 167, Visits: 1.1K
Chris Rogers - 5/11/2020 1:20:43 AM
Massimiliano - 5/10/2020 4:25:52 AM
Chris Rogers - 5/5/2020 9:16:03 PM


Here's a video of the wet-preg method - not super helpful for a flat panel - but it's just to show the process:  https://youtu.be/06-0Vxs_9nY  

Hi, the link is not working... could you please repost it?
Thanks

Sorry - fixed it in the original post.  

Thank you!

Chris Rogers
C
Supreme Being (939 reputation)Supreme Being (939 reputation)Supreme Being (939 reputation)Supreme Being (939 reputation)Supreme Being (939 reputation)Supreme Being (939 reputation)Supreme Being (939 reputation)Supreme Being (939 reputation)Supreme Being (939 reputation)
Group: Forum Members
Posts: 120, Visits: 933
Massimiliano - 5/10/2020 4:25:52 AM
Chris Rogers - 5/5/2020 9:16:03 PM


Here's a video of the wet-preg method - not super helpful for a flat panel - but it's just to show the process:  https://youtu.be/06-0Vxs_9nY  

Hi, the link is not working... could you please repost it?
Thanks

Sorry - fixed it in the original post.  





Damien
Damien
Supreme Being (219 reputation)Supreme Being (219 reputation)Supreme Being (219 reputation)Supreme Being (219 reputation)Supreme Being (219 reputation)Supreme Being (219 reputation)Supreme Being (219 reputation)Supreme Being (219 reputation)Supreme Being (219 reputation)
Group: Forum Members
Posts: 32, Visits: 132
Now except for paying attention when putting the release film as flat as possible, any other tip to limit the little
"folds" of resin on the part that is not against the mould ?


Thanks !
Massimiliano
M
Supreme Being (1.3K reputation)Supreme Being (1.3K reputation)Supreme Being (1.3K reputation)Supreme Being (1.3K reputation)Supreme Being (1.3K reputation)Supreme Being (1.3K reputation)Supreme Being (1.3K reputation)Supreme Being (1.3K reputation)Supreme Being (1.3K reputation)
Group: Forum Members
Posts: 167, Visits: 1.1K
Chris Rogers - 5/5/2020 9:16:03 PM


Here's a video of the wet-preg method - not super helpful for a flat panel - but it's just to show the process:  https://youtu.be/06-0Vxs_9nY  

Hi, the link is not working... could you please repost it?
Thanks

Hanaldo
Hanaldo
Supreme Being (14K reputation)Supreme Being (14K reputation)Supreme Being (14K reputation)Supreme Being (14K reputation)Supreme Being (14K reputation)Supreme Being (14K reputation)Supreme Being (14K reputation)Supreme Being (14K reputation)Supreme Being (14K reputation)
Group: Forum Members
Posts: 2.5K, Visits: 28K
Yeh it's super tough to stomach going back to wet-lay after having worked with proper pre-preg. Hell, even infusion is just a bit unpleasant with all the extra consumables etc. 

Wait till you've tried tooling pre-pregs! Regular tooling is just agony after that.
Damien
Damien
Supreme Being (219 reputation)Supreme Being (219 reputation)Supreme Being (219 reputation)Supreme Being (219 reputation)Supreme Being (219 reputation)Supreme Being (219 reputation)Supreme Being (219 reputation)Supreme Being (219 reputation)Supreme Being (219 reputation)
Group: Forum Members
Posts: 32, Visits: 132
Dear all,

Thanks a lot for all your advices ! I did give a shot to OOA prepreg , and the results are stunning. First, it was so much nicer to manipulate...no epoxy and pieces of carbone fiber all over the place, less toxic, easier to put in place (I did spend a lot of time on how to cut the different parts and it was great, with a very consistent thickness). Then at the end of the day, in one afternoon, the part is ready, so faster than with the epoxy...and the results are awesome. OK, I can improve my technique a bit (a few microholes there and there...but to be honest, I forgot to vaccuum-bag for a while after the first layer as suggested on the EC  website...and I got some left-over prepreg from a friend, which is pre-preg for autoclave, not oven...so I applied the same curing time than suggested for the EC OOA prepreg and it worked just fine, but the prepreg I used is not optimised for that...so I am sure with the proper prepreg, it will be even better).
Anyway,  I am sold ! I will keep using wet layup for large and simple parts, but for smaller and complicated one, I will do it with prepreg for sure.
THanks  for all the tips !!!


Chris Rogers
C
Supreme Being (939 reputation)Supreme Being (939 reputation)Supreme Being (939 reputation)Supreme Being (939 reputation)Supreme Being (939 reputation)Supreme Being (939 reputation)Supreme Being (939 reputation)Supreme Being (939 reputation)Supreme Being (939 reputation)
Group: Forum Members
Posts: 120, Visits: 933
I agree with everybody who says don't try it in one piece!  Hanaldo's idea of using a wet-preg method with plastic on both sides is what I'd do - especially if you don't have / haven't used pre-pregs.  It is a great way to really controlled wet-layup.  Infusion would be good too.

Here's a video (scroll down a bit in link) of the wet-preg method - not super helpful for a flat panel - but it's just to show the process: 
https://explorecomposites.com/materials-library/laminate-sample-15-vacuum-bagged-wet-layup-carbon-with-foam-core/

You'll need to pattern everything pretty well before you start the layup and with 1600-2000g of material (2mm) you have plenty of room for slip joints / laps at the joints with other plies cut back and butted - if it's really critical to have it all 2mm.  You may need to do a little grinding but it should come out well if you are careful about slip joints in the material (and bagging consumables) and leave plenty of bag in the inside corners.




Edited 4 Years Ago by Chris Rogers
Hanaldo
Hanaldo
Supreme Being (14K reputation)Supreme Being (14K reputation)Supreme Being (14K reputation)Supreme Being (14K reputation)Supreme Being (14K reputation)Supreme Being (14K reputation)Supreme Being (14K reputation)Supreme Being (14K reputation)Supreme Being (14K reputation)
Group: Forum Members
Posts: 2.5K, Visits: 28K
Yeh you just need to plan your overlaps correctly in order to not get a step in the laminate thickness.

Doing this part in one piece without any joints in the material may be possible, but very very difficult. Expect several unsuccessful attempts while you learn how the material behaves, you will certainly end up with bridging all over the place initially. 
oekmont
oekmont
Supreme Being (3.4K reputation)Supreme Being (3.4K reputation)Supreme Being (3.4K reputation)Supreme Being (3.4K reputation)Supreme Being (3.4K reputation)Supreme Being (3.4K reputation)Supreme Being (3.4K reputation)Supreme Being (3.4K reputation)Supreme Being (3.4K reputation)
Group: Forum Members
Posts: 550, Visits: 27K
As I would consider it possible done with infusion, it should be possible with prepreg with the help of a heat gun. I would definitely not do it. I would cut out the middle bump for the first layer, and do it with a second piece with a 1cm overlap. The next layer than leaves out the 1cm overlap section. The third one again with overlap and so on. This looks like a small car interior part. 2mm would be way overengineered for that.

Damien
Damien
Supreme Being (219 reputation)Supreme Being (219 reputation)Supreme Being (219 reputation)Supreme Being (219 reputation)Supreme Being (219 reputation)Supreme Being (219 reputation)Supreme Being (219 reputation)Supreme Being (219 reputation)Supreme Being (219 reputation)
Group: Forum Members
Posts: 32, Visits: 132
oekmont - 5/2/2020 9:50:23 AM
No, that won't work. And if you might get it down the part will look horrible, because the fibres will be disoriented quite a lot. The main problem is the prismatic shape in the middle. Fibres which go across this shape will need to be much longer than fibres which run flat along the shape. This will leave a heavily diagonally streched area on both sides of the shape. This isn't a prepreg problem, this will always be the case.


Thanks ! Now if I don't mind something that is not good aesthetically speaking, is it doable ? If not, do you think that I can use a single piece for the entire part except for that prismatic shape in the middle, cutting my prepreg just at the edge of it, and then use separate parts for that prismatic form ?

GO

Merge Selected

Merge into selected topic...



Merge into merge target...



Merge into a specific topic ID...




Similar Topics

Reading This Topic

Explore
Messages
Mentions
Search