First Carbon Fibre part

8So, this is my first carbon-fibre part. It is a resin-infusion aramid/foam/glass/carbon part designed to replace a aluminium floor panel.  Unlike the aluminium part which was riveted in, the composite part will be bonded in for good. This will reduce weight and increase rigidity in the chassis. All in all, I’m really pleased with the result, and the pictures below will show how I made it, and how strong it is.

The layup of the part is:

What Specification
Aramid 2/2 Twill Weave 300g
Closed Cell Foam 10mm
E-Glass 2/2 Twill 200g
Carbon Fibre 2/2 Twill 12k 450g
Epoxy Resin Normal, Slow

As I said in the previous post, there was a journey finding the right medium to lay the part out on, and found a double-glazing window worked a treat.

2

Now that the parts are laid on the glass and vacuum bagged, I infused 200g of resin through. Sure enough, this wasn’t enough, so I stopped the infusion process, added another 100g of resin and completed the process. The infusion process slowed down towards the end, and the far-right corner was the last to fill. Just as the corner filled, I had the input clamp tight, so the corner filled from resin already in the part. I don’t think I had too much resin in there.

3One fully infused, vacuum bagged part, sitting in the sun curing. I was lucky in having to work away from home for three days when the UK weather was the best its been for a while so the part got a proper baking. For slow resin, 24 hours is a minimum before demoulding, and 36 is better. I got 72, with three hot blasts of the mid-day sun.

 

4Here’s the part popped from the mound. The easy-lease compound (4 applications, as per the instructions) worked a treat and the part popped off the glass without a fight. You can see the aramid (yellow), which is the underside part of the car, facing the road surface. Aramid gives brilliant impact protection. It’s also incredibly strong, and a little more giving than carbon-fibre on its own.

5Here’s the side of the part that faces into the footwell. You can see the infusion spiral and resin bung still on the part because I haven’t removed the peel-ply yet that this lot is all stuck to.

 

 

6

Lo and behold it came to pass that the part was peeled and trimmed.

 

 

 

9Here’s the finished part, sat on two tins of soup, with my not inconsiderable self balancing on top of it. Note the lack of deflection.

 

 

The original aluminium part weighed 960g, and this part weighs 524g. That’s a 55% saving in weight.

Happy with this.

CREDITS

This wasn’t the easiest of starts, and I had some good technical support from Matt at Easy Composites and lots and lots of moral support, texts, phone calls, tea and training from Warren at Carbon Copies.