Homemade CFRP mid engine sports car

Spectacular CF suspension pieces, at least to the unfamiliar. It would be very interesting to see some detail in process shots of how these were created.
Way Cool.
 

Chris Kouba

Supporter
...It would be very interesting to see some detail in process shots of how these were created...

Rob- He's got a good start to that post 34 and 36:



Way cool indeed!!!
 
amazing level of fabrication here, very cool. One comment on open front design - I think it will generate significant lift at speed, all that air will pack into the wheel wells as there is a choke point between the tires and the chassis that will not allow easy escape. A rigid flap in front of the wheel, with an air extractor at the top, going through the fender surface, would allow the air to escape without creating a high pressure zone under the body work.
 
Hi Tom, yes I had been wondering the same. I'll likely either add a vent over the fender, or adjust the trim line for the hood to pull it outboard nearer the tyre, let the air bleed round the side. I'm also concerned about the rear, the engine bay is very open, lots of drag, and not very practical, but for me this was an important styling feature. Its still kinda hard for me to visualise the overall styling, how it will look in the flesh, I expect once it starts coming together I might change my mind here and there.

Mesa - I plan to laminate another CF layer on a wishbone this weekend, i'll take some photos as i go.
 
Mesa - Here's some snaps showing the process. First, make sure you have everything prepped. Once you start you'll have sticky hands and the clock will be ticking so I get all the plies cut out and counted, find a good movie to put on and open a beer all before the epoxy is mixed. step 2, mix the epoxy and paint it over the part, then apply the CF ply, then apply more resin, brush all over and place the next ply, etc. This evening I was putting down 5x plies of 200gsm UD all over, which gives me just over 1mm of CF. It took me two and a half hours to get all 5 plies down all over which is all the time I have before the resin starts to gel, so I'll need to repeat this activity several more times on other days. This is layer 2 of 5 layers that I will put down, theis UD sits at the middle of the stack. Once all plies down, I wrap in perforated release film, then in breather fabric. Any excess resin will bleed into this. Then into the vacuum bag to compress it down .. then check for air leaks .. this is the part I dread, at this stage i'm tired and I don't enjoy hunting for air leaks. Once airtight I clamp off and take the part inside the house to cure in the warm. Once cured i'll unwrap and tidy up the surface, sand off any resin flash between the crinkles in the release film and abrade the CF ready for the next layers to go down.

Once all structural plies are down, I sand the part smooth, any bad lumps I might use filler, then I stick a final cosmetic CF fabric over the top with spray adhesive. Then lots and lots of resin over the top, sand down the grits until ready to be polished to gloss.

This part I also need to drill and tap holes and insert helicoils. I use a 3D printed jig to align where to drill so I can find the Ali inserts embedded in the part OK.

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Mesa - Here's some snaps showing the process. First, make sure you have everything prepped. Once you start you'll have sticky hands and the clock will be ticking so I get all the plies cut out and counted, find a good movie to put on and open a beer all before the epoxy is mixed. step 2, mix the epoxy and paint it over the part, then apply the CF ply, then apply more resin, brush all over and place the next ply, etc. This evening I was putting down 5x plies of 200gsm UD all over, which gives me just over 1mm of CF. It took me two and a half hours to get all 5 plies down all over which is all the time I have before the resin starts to gel, so I'll need to repeat this activity several more times on other days. This is layer 2 of 5 layers that I will put down, theis UD sits at the middle of the stack. Once all plies down, I wrap in perforated release film, then in breather fabric. Any excess resin will bleed into this. Then into the vacuum bag to compress it down .. then check for air leaks .. this is the part I dread, at this stage i'm tired and I don't enjoy hunting for air leaks. Once airtight I clamp off and take the part inside the house to cure in the warm. Once cured i'll unwrap and tidy up the surface, sand off any resin flash between the crinkles in the release film and abrade the CF ready for the next layers to go down.

Once all structural plies are down, I sand the part smooth, any bad lumps I might use filler, then I stick a final cosmetic CF fabric over the top with spray adhesive. Then lots and lots of resin over the top, sand down the grits until ready to be polished to gloss.

This part I also need to drill and tap holes and insert helicoils. I use a 3D printed jig to align where to drill so I can find the Ali inserts embedded in the part OK.

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Thanks for the description, that is one involved process! How many hours will you have in each piece?
Step One - Open a Keg.
Appreciate all the work that went into these, with your basics I may try this myself.
 
end of year update .. finished the moulds for the LH door now. Next i'll be working on the RH door and finally the upper structure - that should take me up to the spring. Then I can give the garage a proper clean out and get ready for the next stage.

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Neat build! Pretty amazing.
I don't know if you have seen this guy's YouTube channel, but he has a ton of videos about moulds and composite layups. Lots of tips and tricks for the garage builder. Definitely a redneck approach to composite body panels but he gets the job done...Maybe you already are a pro... I've learned a bit from him.
 
Thank Dave, I'd not seen that particular one but I think I've seen another video of the same guy forming his own screens from polycarbonate. Lots of good ideas ..
 
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