Homemade CFRP mid engine sports car

Spent most of the last week making lots and lots of little brackets for suspension mounts. Fitted the front suspension, went mostly ok, I was worried the inserts in the tub might have drifted a bit but everything seems in the right place. Still need to machine some brackets to lift the steering rack to the right height before i can fit that.

Also moulded one of the rear end inner panels. I used high temp resistant epoxy as will be close to the exhaust, this stuff is more viscous so has to be hand laminated, a messy job ! once i've moulded the other side too i'll post cure them both under an IR lamp. Need to make some inserts to fit under them before fitting.

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Chris Kouba

Supporter
Paul,

Fantastic work! Can you share more regarding how you locate/secure the suspension/rack/etc inserts when laying up the tub? That part of composite construction has always fascinated me- the application of point loads on sheet surfaces and how you get the metal and composite to remain reliably bonded. How is it done?

Chris
 
Thanks guys, Chris the main thing with the inserts is to get a large surface area, big enough so that the load to pull it through the CF is larger than the bolt strength (circumpherence of insert x thickness of CFRP x CFRP shear strength) . The biggest challenge i have is alignment, on a normal professional build all the holes would be machined on a big multi axis machine at the end, but since i don't have that luxury i used 3d printed frames to hold the pre-drilled inserts in place during the layup stage. post #64 shows some photos. The pockets in the tub surface for the wishbones also help mechanically lock the frames more or less in place too. This whole thing is not super accurate so there is a level of adjustment with oversized holes in the wishbone brackets too.
 
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