chassis stiffening with carbon Options

[dian]

i have not found any evidence that it has been done. why not?

how much easier would it be to epoxy glue some carbon in certain areas than to weld. at least if you dont have a big shop. (if i start welding in my garage, the whole house stinks for a week.)

so is this a crazy idea or has anybody done it? supposedly it would save weight too. is it just too expensive, maybe?

thanks for any opinions, before i research this further.

[worn]

i have not found any evidence that it has been done. why not?

how much easier would it be to epoxy glue some carbon in certain areas than to weld. at least if you dont have a big shop. (if i start welding in my garage, the whole house stinks for a week.)

so is this a crazy idea or has anybody done it? supposedly it would save weight too. is it just too expensive, maybe?

thanks for any opinions, before i research this further.

I suspect it is simply more difficult to do right. Adhesion is one thing, but if clean, the metal and epoxy should bond. And then there is shape - if I was going to the trouble I would want to design ribbed structures for strength. Might be hard to know which shapes to do though. Good luck.

[gothspeed]

It is a freakin great idea (IMG:style_emoticons/default/smile.gif)! things like this are done on race chassis and aerospace all the time. If you can cut the carbon sheets to fit (waterjet?) .... then prepping (roughing) mating surfaces ... you can bond carbon sheets to bare steel at room temperature with Hysol Loctite EA 9394, .... it is a bit expensive but the Hysol is just about the best epoxy for this type of application ......... as you surmised, carbon sheet reinforcements will work extremely well, for light weight doublers and chassis stiffeners ......... (IMG:style_emoticons/default/beerchug.gif)

[damesandhotrods]

It’s been a while but to get full strength, wouldn’t the steel and carbon fiber have to be glued under vacuum?

[76-914]

It's been done. I used EGlass and Aero Poxy. 5x stronger than steel and good to 450F. I had some small rust issues which I cut out. I Marine cleaned and treated the metal inside the long (which was in excellent condition but that damned O.C.D. wins out every time) and then laid up 5 layers. While I was at it I built the battery box with a drain. I use a regular cheap battery and don't worry about water rinsing acid upon the metal any longer. After it is prepped you should be able to glass it up in one afternoon. Which ever glass media that you pursue, be sure the weave allows bi-directional installation. Mike (aka Ruby914) is our real glass expert and I will defer to any comments he might add to this. Here's a couple of shots I found. I think I may have lost (read crash) most of them but you get the idea. 3 yr's and many hard turns later it is still tighter than socks on a rooster.

[Zimms]

It's been done. I used EGlass and Aero Poxy. 5x stronger than steel and good to 450F. I had some small rust issues which I cut out. I Marine cleaned and treated the metal inside the long (which was in excellent condition but that damned O.C.D. wins out every time) and then laid up 5 layers. While I was at it I built the battery box with a drain. I use a regular cheap battery and don't worry about water rinsing acid upon the metal any longer. After it is prepped you should be able to glass it up in one afternoon. Which ever glass media that you pursue, be sure the weave allows bi-directional installation. Mike (aka Ruby914) is our real glass expert and I will defer to any comments he might add to this. Here's a couple of shots I found. I think I may have lost (read crash) most of them but you get the idea. 3 yr's and many hard turns later it is still tighter than socks on a rooster.

Do you have any more finished photos? That's pretty cool.

[gothspeed]

It’s been a while but to get full strength, wouldn’t the steel and carbon fiber have to be glued under vacuum?

I think you mean an Autoclave .... that is used to apply heat and vacuum to cure the carbon resin ....... but if the OP is using pre-cured flat carbon sheets ........ it can be done at atmospheric/sea level pressure ....... if one has the ability, one can 'out gas' the epoxy in a vacuum chamber after mixing ...... apply it, then make sure you have a good way of clamping/pressing the entire carbon sheet onto the longs or what ever part one is reinforcing. However as I posted before, one can just prep, mix and bond ....... anything further is extra.

I think is it great way to gain some chassis stiffness, mitigate some of the weight and possible body warping of the 'weld in' steel reinforcements.

[brant]

I think K.I.S.S. applies here....

[dian]

i believe an autoclave is used for prepreg carbon and vacum is used to press out unneccessary resin to gain some weight. (which i wouldnt bother with.)

[URY914]

I think K.I.S.S. applies here....

Agree. (IMG:style_emoticons/default/idea.gif)

[gothspeed]

i believe an autoclave is used for prepreg carbon and vacum is used to press out unneccessary resin to gain some weight. (which i wouldnt bother with.)

+1 .......... as I mentioned in post #3 ........ the bonding would be a straight forward process ..... what parts of the chassis will you be doing this to (IMG:style_emoticons/default/smile.gif)?

Since you brought this idea up ......... in some areas, I think it is a much better alternative than than the weight adding 'weld in' plates ........ (IMG:style_emoticons/default/smoke.gif)

[patrick3000]

i have not found any evidence that it has been done. why not?

how much easier would it be to epoxy glue some carbon in certain areas than to weld. at least if you dont have a big shop. (if i start welding in my garage, the whole house stinks for a week.)

so is this a crazy idea or has anybody done it? supposedly it would save weight too. is it just too expensive, maybe?

thanks for any opinions, before i research this further.

I think you would have better results making a carbon top

[Rand]

FYI, this has been discussed here before. Not sure the best search terms, but try.

[IronHillRestorations]

As stated, real carbon fiber composite components are compression molded and cured in an autoclave.

Most of the carbon fiber hoods and parts you see are just simply carbon fiber mat used in place of common fiberglass mat, and is not any stronger than the fiberglass counterpart.

To have true structural carbon fiber components is very spendy.

At some point the fiberglass repair shown above will separate from the metal in some way. It might last a long time, but it will happen.

[gothspeed]

I could be wrong but I thought the OP was looking into bonding flat sheets (already autoclaved) onto flat areas of the chassis, where reinforcement is desired. So basically buying some sheets (from the link below), cutting them or having them waterjet cut to fit a flat area of the chassis.

http://dragonplate.com/ecart/categories.asp?cID=65

As stated, real carbon fiber composite components are compression molded and cured in an autoclave.

Most of the carbon fiber hoods and parts you see are just simply carbon fiber mat used in place of common fiberglass mat, and is not any stronger than the fiberglass counterpart.

To have true structural carbon fiber components is very spendy.

At some point the fiberglass repair shown above will separate from the metal in some way. It might last a long time, but it will happen.

+1 .... I agree, if my assumption was correct ........ the Eglass picture above is not what the OP had in mind.

For bonding 'pre-autoclaved' flat carbon sheets, one would only need the Hysol epoxy bond I noted above. With proper prep it would be a very nice, light weight reinforcement.

I may consider doing this on some areas (IMG:style_emoticons/default/smile.gif)