Comparison carbon fiber vs skin on frame canoe?

[fairing guy]

Hello,

Skin on frame has been touted by some as a light weight method of canoe construction.

How does this method compare to vacuum resin infusion carbon fiber construction?

How much lighter is one method to the other?

How much more slower/inefficient is the canoe built using one method other the other?

I look forward to the answers to these burning questions.

 

[ondarvr]

What is the objective, ultra light with no compromise, or light but durable enough to survive real life use.

 

[fallguy]

Vacuum resin infusion is a rather complex building method.

Skin on frame is much simpler.

Errors in infusion can ruin the entire part. Errors in sof are easily repairable or easier at least.

learning infusion is also more difficult

the comparison is really apples and oranges

 

[fairing guy]

The objective is a fairing that is as light as possible.
It has to be strong enough to not be damaged by the wind or rain and manual handling of the bike.

The Recumbent Bicycle and Human Powered Vehicle Information Center http://recumbents.com/wisil/gritters/rick_gritters.htm

 

[gonzo]

If the goal is light weight, you should start by getting rid of those huge pipes. The frame and supports are massive. It is hard to find a fairing in that size that is lighter and more rigid than a wooden structure.

 

[fallguy]

It looks like a first stage would be sof and then you could go to infusion of carbon.

for the carbon; you would need to build a plug

you could probably start on a smaler portion of the shell and work your way up to the whole thing...

if, for example you have something not in the half shell; you could build that first

another thought would be to build a shell in 6mm corecell foam; later that could be reinforced and used as a plug

 

[fairing guy]

Here is another example: light velomobile concept http://mosquito-velomobiles.com/concept.htm

16-21 kg for the whole vehicle.
That fairing must be very light weight.

 

[Rumars]

You must compare apples to apples not to oranges. Meaning that total structure weight must be considered. For your first example a light windproof fabric will probably be lighter. Your second example has a choice, replace the geodesic frame with a carbon sandwich shell and it will come out on top. The question becomes what other functions that frame has. If it has to provide impact protection for the rider the whole thing changes again.

 

[fairing guy]

The fairing is nonstructural. Mounted to an existing frame.

 

[fallguy]

Honestly, I would build a carbon frame and find a way to apply a windproof skin.

 

[Rumars]

The fairing is nonstructural. Mounted to an existing frame.

If the frame stays in place it is impossible for the amateur to replicate in carbon what can be achieved with (high tech) fabrics. Examples:
Dyneema® Composite Fabric is available in 12g/square meter.
Silicon, PU or TPU coated (ripstop) nylon begins at around 30 g/sqm.
Unreinforced PET film can be even lighter then DCF. Just shrinkwrap the bike.
The downsides of such light fabrics is limited abrasion resistance. "Handle with care" is a must.