MGB Front Suspension Crossmember and Hood (Bonnet)

Talk Composites - The Forum for Advanced Composites

Back

MGB Front Suspension Crossmember and Hood (Bonnet)

Author	Message
Airwreckc	A Airwreckc posted 4 Years Ago HOT Topic Details
A Group: Forum Members Posts: 2, Visits: 6	I'm new to composites, so I'm exploring a couple of ideas. I am working on an MGB with a V8 conversion. The engine is somewhat heavier than a standard V8, so I'm thinking of replacing the front suspension crossmember to save weight. There are aftermarket front suspensions made from steel tube that can save weight, but they are EXTREMELY expensive ($3,500-4,000). I was thinking of replicating the existing crossmember in carbon fiber. Since it's under the car, it wouldn't need a perfect finish, so it might be a good learning experience. Does anyone know if carbon fiber would be strong enough for this sort of application--and if so, how many layers of what thickness material would be needed? Does anyone have any idea of the cost of the materials? Finally, I'm also considering doing a carbon fiber hood (bonnet) after I get my skills up--any idea of the weight difference between a typical steel hood and one made with carbon fiber--and again, and idea of the cost of the materials for this project? Thanks for any advice
	Reply Like 3
Steve Broad	Steve Broad posted 4 Years Ago HOT Post Details
Group: Forum Members Posts: 408, Visits: 4.1K	+x Airwreckc - 5/23/2020 12:07:51 AM I'm new to composites, so I'm exploring a couple of ideas. I am working on an MGB with a V8 conversion. The engine is somewhat heavier than a standard V8, so I'm thinking of replacing the front suspension crossmember to save weight. There are aftermarket front suspensions made from steel tube that can save weight, but they are EXTREMELY expensive ($3,500-4,000). I was thinking of replicating the existing crossmember in carbon fiber. Since it's under the car, it wouldn't need a perfect finish, so it might be a good learning experience. Does anyone know if carbon fiber would be strong enough for this sort of application--and if so, how many layers of what thickness material would be needed? Does anyone have any idea of the cost of the materials? Finally, I'm also considering doing a carbon fiber hood (bonnet) after I get my skills up--any idea of the weight difference between a typical steel hood and one made with carbon fiber--and again, and idea of the cost of the materials for this project? Thanks for any advice In three words...DON'T DO IT! The stresses encounterd by the crossmember are numberous and high. Attempting to build a carbon fibre crossmember to deal with these, especially as a first project, is foolhardy to say the least, IMO. There are probably guys on here who have done this, but it wouldn't be a simple task if you want to make sure that you don't die. Stick with items that aren't structural, like the bonnet/hood as a failure here will be a learning experience that won't kill you.
	Reply Like 3
Airwreckc	A Airwreckc posted 4 Years Ago HOT Post Details
A Group: Forum Members Posts: 2, Visits: 6	Thanks Steve, I appreciate the advice. Any thoughts as to the cost of materials for a hood/bonnet?
	Reply Like 3
Steve Broad	Steve Broad posted 4 Years Ago HOT Post Details
Group: Forum Members Posts: 408, Visits: 4.1K	+x Airwreckc - 5/23/2020 10:32:41 AM Thanks Steve, I appreciate the advice. Any thoughts as to the cost of materials for a hood/bonnet? How long is a piece of string? :-) SO many variables. Wet lay (fabric plus resin) only, wet lay with vacuum bagging, vacuum infusion or prepreg? Size of bonnet How many skins (top and support frame?) How many layers of carbon (ie how stiff do you want it?) Carbon fabric weight./m2 Answer these and a rough price can be worked out. Be aware that it won't be cheap.
	Reply Like 4