is foam core fiberglass enough strength to be chassis?
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- RichardSIA
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Re: is foam core fiberglass enough strength to be chassis?
What I saw in the video I would say no, mock-up only.
Lots of discussion in this oldish thread,
viewtopic.php?f=39&t=18798&hilit=carbon+fiber
But I still plan to do a plywood/foam main structure for my Tatum-13B Suzuki build.
Major difference is in the use of foam only as a filler for the wood structure.
Engine cradle will be tube steel attached to the rear bulkhead.
Lots of discussion in this oldish thread,
viewtopic.php?f=39&t=18798&hilit=carbon+fiber
But I still plan to do a plywood/foam main structure for my Tatum-13B Suzuki build.
Major difference is in the use of foam only as a filler for the wood structure.
Engine cradle will be tube steel attached to the rear bulkhead.
If I must be a one-man PC free zone, so be it!
- ngpmike
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Re: is foam core fiberglass enough strength to be chassis?
It would probably take some engineering, but could be done! Jim Hall's Chaparral 2 race cars were a fiberglass monocoque, and there are a lot of foam and F/G airplanes flying around now!
Mike - Read my story at http://twinlakesseven.blogspot.com/
- BostonWill
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Re: is foam core fiberglass enough strength to be chassis?
My ex-brother-in law had a company that built composite experiential planes for decades (including military drones)! It can be done, but you really need to know what you're doing. It would take some serious engineering
Thom
Thom
Thom
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Re: is foam core fiberglass enough strength to be chassis?
BostonWill wrote:My ex-brother-in law had a company that built composite experiential planes for decades (including military drones)! It can be done, but you really need to know what you're doing. It would take some serious engineering
Thom
if it really work, there are many things can do
e.g. 3d print foam core parts
- ngpmike
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Re: is foam core fiberglass enough strength to be chassis?
The experimental aircraft arena is probably your best bet for advice and inspiration! One of the best books that I know of is "Moldless Composite Sandwich Aircraft Construction" by Burt Rutan. There are others out there but Rutan is one of the pioneers with an impressive track record!
Mike - Read my story at http://twinlakesseven.blogspot.com/
- benny_toe
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Re: is foam core fiberglass enough strength to be chassis?
I think all F1 and Indy cars are carbon fiber tubs these days. The carbon is stronger than GRP for a given thickness ut for stress points you can make the GRP thicker.
Often thought about this but I really don't know enough go any further than wondering.
Often thought about this but I really don't know enough go any further than wondering.
Larry in Seattle
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Re: is foam core fiberglass enough strength to be chassis?
benny_toe wrote:I think all F1 and Indy cars are carbon fiber tubs these days. The carbon is stronger than GRP for a given thickness ut for stress points you can make the GRP thicker.
Often thought about this but I really don't know enough go any further than wondering.
carbon is more expensive than GRP
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Re: is foam core fiberglass enough strength to be chassis?
ngpmike wrote:The experimental aircraft arena is probably your best bet for advice and inspiration! One of the best books that I know of is "Moldless Composite Sandwich Aircraft Construction" by Burt Rutan. There are others out there but Rutan is one of the pioneers with an impressive track record!
it really quiet strong
https://www.youtube.com/watch?v=biZ2Sl63nr0
- Johnsinski
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Re: is foam core fiberglass enough strength to be chassis?
The BEC book talks about aluminum honeycomb construction and bonding stuff together. I wouldn't trust my skills on that. Welding steel is relatively easy and reliable.
But that foam build video is very cool. Some serious skills that guy has. I may do a seat build thread for my BEC, I CNCed a foam mold for that, albeit one sided. But you could "fairly easily" CNC both sides to make a foam core. You'd need a BIG 3d printer to print part cores, but maybe it could be done.
But that foam build video is very cool. Some serious skills that guy has. I may do a seat build thread for my BEC, I CNCed a foam mold for that, albeit one sided. But you could "fairly easily" CNC both sides to make a foam core. You'd need a BIG 3d printer to print part cores, but maybe it could be done.
"It ain’t what you don’t know that gets you into trouble, it’s what you know for sure that just ain’t so."
"Sometimes I sits and thinks, sometimes I just sits." - Satchel Paige
"Sometimes I sits and thinks, sometimes I just sits." - Satchel Paige
- Driven5
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Re: is foam core fiberglass enough strength to be chassis?
That partially depends how you define 'enough strength':
Enough strength to survive the first drive? Easy.
Enough strength to survive 10's or 100's of thousands of miles of street and/or track abuse? Considerably harder.
Enough strength to survive an at-speed crash? Even harder yet.
There is a reasonably large body of knowledge regarding the strength, fatigue resistance, and survivability of welded steel tube car chassis. There is not for foam core fiberglass car chassis. Airplanes tend to be better shaped for composite use than most cars are.
Much like an aluminum monocoque, I'm not saying it can't be done to an acceptable (or even superior) level...Just that the standard of proof before I'd trust my own life to riding in one at highway (or greater) speeds would be much higher than for a tried and true steel tube frame.
Enough strength to survive the first drive? Easy.
Enough strength to survive 10's or 100's of thousands of miles of street and/or track abuse? Considerably harder.
Enough strength to survive an at-speed crash? Even harder yet.
There is a reasonably large body of knowledge regarding the strength, fatigue resistance, and survivability of welded steel tube car chassis. There is not for foam core fiberglass car chassis. Airplanes tend to be better shaped for composite use than most cars are.
Much like an aluminum monocoque, I'm not saying it can't be done to an acceptable (or even superior) level...Just that the standard of proof before I'd trust my own life to riding in one at highway (or greater) speeds would be much higher than for a tried and true steel tube frame.
-Justin
"Orville Wright did not have a pilots license." - Gordon MacKenzie
"Orville Wright did not have a pilots license." - Gordon MacKenzie
- a.moore
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Re: is foam core fiberglass enough strength to be chassis?
"Is it strong enough?" - the simple answer is yes.
Its strength and elongation properties put it at a disadvantage to carbon fiber since you will need more of it to get the strength but the extra stiffness will hurt its ability to absorb energy in an impact without failing (think brittle vs. ductile materials).
The design requirements to successfully build a composite monocoque are not difficult but definitely a few levels above designing a steel space frame. You need to worry about ply orientation, the number of plies, and how you handle things like lapjoints and high stress areas where suspension components, seats, seatbelts, and rollbars attach.
Its strength and elongation properties put it at a disadvantage to carbon fiber since you will need more of it to get the strength but the extra stiffness will hurt its ability to absorb energy in an impact without failing (think brittle vs. ductile materials).
The design requirements to successfully build a composite monocoque are not difficult but definitely a few levels above designing a steel space frame. You need to worry about ply orientation, the number of plies, and how you handle things like lapjoints and high stress areas where suspension components, seats, seatbelts, and rollbars attach.
- RichardSIA
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Re: is foam core fiberglass enough strength to be chassis?
a.moore wrote:"Is it strong enough?" - the simple answer is yes.
Its strength and elongation properties put it at a disadvantage to carbon fiber since you will need more of it to get the strength but the extra stiffness will hurt its ability to absorb energy in an impact without failing (think brittle vs. ductile materials).
The design requirements to successfully build a composite monocoque are not difficult but definitely a few levels above designing a steel space frame. You need to worry about ply orientation, the number of plies, and how you handle things like lapjoints and high stress areas where suspension components, seats, seatbelts, and rollbars attach.
Yet, the plywood Marcos 1600's were remarkably simple and more rigid than the space-frame design that followed.
Basic design criteria remains the same, create boxes and triangulation as much as possible.
Foam core can be useful, but so can a simple expanded cardboard spacer.
My Tatum build is still fairly far down the list but I have done a few very basic chassis sketches.
I will have to do them again as Paper & Pencil 1.0 does not post well.
If I must be a one-man PC free zone, so be it!
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Re: is foam core fiberglass enough strength to be chassis?
RichardSIA wrote:a.moore wrote:"Is it strong enough?" - the simple answer is yes.
Its strength and elongation properties put it at a disadvantage to carbon fiber since you will need more of it to get the strength but the extra stiffness will hurt its ability to absorb energy in an impact without failing (think brittle vs. ductile materials).
The design requirements to successfully build a composite monocoque are not difficult but definitely a few levels above designing a steel space frame. You need to worry about ply orientation, the number of plies, and how you handle things like lapjoints and high stress areas where suspension components, seats, seatbelts, and rollbars attach.
Yet, the plywood Marcos 1600's were remarkably simple and more rigid than the space-frame design that followed.
Basic design criteria remains the same, create boxes and triangulation as much as possible.
Foam core can be useful, but so can a simple expanded cardboard spacer.
My Tatum build is still fairly far down the list but I have done a few very basic chassis sketches.
I will have to do them again as Paper & Pencil 1.0 does not post well.
is marcos 1600 mean this?
https://www.google.com/search?q=Marcos+ ... HK707HK707
- RichardSIA
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Re: is foam core fiberglass enough strength to be chassis?
Yes, my old one is probably on there somewhere.
The main body did become the final chassis member.
The main body did become the final chassis member.
If I must be a one-man PC free zone, so be it!
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