loopingz wrote:
Hi there,
I love your project mke. I have seen you want to build cf wheels on a budget.
As a pro (aerospace composite engineer) and hobbyist board builder I would like to stress some points here.
Prepare yourself to waste some wheels at least you have to budget it.
What can go wrong.
By conception matting on the screws will be hard. Be monolotic around there. Ply orientation and quantity is vital at least a minimum thickness is vital.
The shape on the 308 is not very carbon fiber friendly. Koenigsegg put some tubic branch and everything is rounded.
By tooling. Vacuum pump go for industrial straight. My 3 free fridge pump + relays and microcontrollers is around 500$ and yet not that good (3 pump is for redundancy here). Oven you will need one and you will need to cook high temp 200C minimum 400C would be better. Mine is "almost free" but reach only 70C. You need to control ramp up and ramp down temperature. Failure to do so = trash.
By building. You can have mass reaction (better to constantly mix resin and never more than half inch high in your bucket), avoid it at all cost. You will have bubble visible outside and hidden inside. How much can you tolerate?. Warping, that is a wheel you need to avoid it a lot. Milling afterward should be limited to a minimum! You can have vacuum failure, oven failure, epoxy too humid... Prepreg can remove some issues. Molding will be key. Infusion is interesting too but it might be trickier for a start. If you want to use some filling material you may want use herex/airex, c70-75 or stronger. Avoid honeycomb too much added pain...
You can have delamination too and a lot more possible issue.
It is doable still with your energy I am sure you can manage. But take your budget and multiply by a factor 2, 3 or 4. There is so much to learn!
So if I am reading this correctly, it says, "Pull the engine and fix the seats, buy some cool wheels and drive the shit out of the car this summer."
Did I miss something?