Delrin or Carbon Fibre

[Mides]

I am looking at making my own chassis after breaking a Delrin one I bought (solid 3 foot fall to rocks straight onto its roof).

I have heard that Delrin is lighter than CF? Is this true? I have done some research and I have read conflicting results.

Also, would 2mm thick CF be a good thickness for a chassis? The Delrin one I broke was 3mm.

Thanks guys.

[WolverineX]

In my opinion, the 2mm CF will be lighter but it will be too flexible - like torsion chassis. You'll probably need at least 3mm! It's not as strong as you think as it needs plenty of opposing layers for strength.
It will also be a pain to cut cleanly, and the edges wil need sealing with resin (but superglue will do) to stop them fraying/splitting.
I would be careful with dust (if you do use CF) as it is a health hazard, and if you get a splinter from it, it can snap as you try to remove it!
Delrin (homopolymer acetal) is the way to go...IMO!

[brazwewn]

.051 lbs per cubic inch Delrin
.095 lbs per cubic inch Aluminum
.057 lbs per cubic inch Carbon fiber

Here are some numbers I found earlier, no claims at accuracy. As you can see Delrin is slightly lighter than CF. However, you can almost cut the thickness in half with CF from Delrin, while maintaining the rigidity. I switched to CF for this reason.

Wes

[Mides]

Thanks for the replies guys.

And Wolverine, it isn't my entire chassis. Just the top bit that forms the nose and hood of a bodiless. I should have cleared that up a bit.

[Highlucks]

Hey Nick, have a word to Dan he might be able to help you out with some CF replacement parts once we get back from Nats. Have you contacted the original Vendor with your issue?

[Mides]

Originally Posted by highlucks

Hey Nick, have a word to Dan he might be able to help you out with some CF replacement parts once we get back from Nats. Have you contacted the original Vendor with your issue?

Hey Camo, Dan is the one who gave me the idea on Sunday. He doesn't have any carbon fibre. I would have asked if he could make one for me, but I feel like giving it a go myself.

I will need to take picture and contact the original vendor. I am not necessarily blaming him as it was a solid fall and things do break when that happens.

[Highlucks]

True but these things are designed with large falls in mind 3' is not that big in the scheme of things.

Best of luck with the CF upgrades though if you take that course.

[brazwewn]

McMaster Carr has carbon fiber strips. The 3" wide strips are pretty reasonable. Most times you can get what you want from that width.

I have heard a lot about using grinders and cut off wheeels to cut the CF. I know it works but is too messy for me. I used a super thin wood blade on my jigsaw. I made it about halfway through one piece before all the teeth were gone though. In other words buy a few multiple packs. You will need very little sanding when done and can make tight inside cuts. Just remember to tape the surface to keep it shiny. Atleast until the rocks get to it!

Wes

[Highlucks]

Only one problem there. McMaster Carr will not ship to Australia.

[brazwewn]

Originally Posted by highlucks

Only one problem there. McMaster Carr will not ship to Australia.

That sucks! Have any buddies or family over here?

Wes