12 replies to this topic

[Aerodynamic]

Before Xmas I bought a tume of Argon gas and prepaired to start up my never used 10 year old TIG welder.

I have practised but my skills is not improving fast enought and the spring is comming closer and closer everyday.

And my Aluminium sheets I bought many years ago will soon be wasted if my skills is not improving rapidly.

 

I have some more ideas to be tested but if it´s not working I will refuse to give up my plans for a diffuser.

 

So I began to think about using Wood, plywood. I thought about using 4mm plywood

this would actually be lighter then my 1.5mm alumium sheet.

 

I see 2 downsides using plywood

1 is risk of fire down in the rear end of my car.

And if accident then it might crack and not easy to bend back.

 

Else it´s easy to work with easy to shape and plan to glue and screw together the panels.

I also belive the fiberglass Products and polyester will work fine together with the plywood.

 

And what is the best way to protect the Wood from my exhaust manifold? Get some gold foil or some Nimbus protection?

 

What do you think about using plywood?

Or does someone else have any other idea of material that is good to work with or Construction/design ideas?

 

, Per

[Nev]

Have you considered joining your aluminum with pop rivets? Easily done and is a technique for making floor-pans and diffusers on other cars.

 

This technique is also good because if a longitudinal vane gets hit and bends, you can drill out the rivets and replace it easily.

 

I wouldn't use wood myself.

 

Edited by Nev, 11 February 2018 - 06:36 PM.

[Aerodynamic]

yhea I have considered to use pop rivet. But my design isn´t just a flat section. it´s  angled with a big (R1000-1500) radius across.

 

Whats wrong with plywood?

[Nev]

yhea I have considered to use pop rivet. But my design isn´t just a flat section. it´s  angled with a big (R1000-1500) radius across.

 

Whats wrong with plywood?

 

I don't fully understand you, but can't you bend the edges of the downward pointing "vanes" to 90 degrees and rivit these to the main belly plate?  

For the plywood to be strong enough for the main belly pan it would need to be quite thick. Also I think it will suffer from water penetration once stones bounce into it and allow water in (through water paint you use). I expect it would be quite heavy in practice.

Edited by Nev, 11 February 2018 - 06:42 PM.

[Aerodynamic]

One reason I was thinking about weld it was because I wanted a flat underside and overside.

 

I was thinking of adding some reinforce bar on top with some spacing in between so I got free air also on top of the diffuser.

 

Br, Per

[Aerodynamic]

But if i build it in plywood I+m thinking of making the central section in alumiuim since here is the hottest part

from exhaust manifold.

The other section, what do you Think would be best to heat protect the plywood with?

 

 

[pete-r]

Make wooden negative moulds, then make a carbon one and pop rivet the blades to it. Any good boatyard will be able to make you a carbon/Kevlar/GRP part if you don't have the equipment or desire to DIY and for much less cash than anywhere with the word motorsport in the name LOL.

Edited by pete-r, 12 February 2018 - 01:53 PM.

[Aerodynamic]

How heat resistant is fiberglas or carfbonfibre to heat. I guess it the same as wood. A good idea. But maybe something for next year.

Make wooden negative moulds, then make a carbon one and pop rivet the blades to it. Any good boatyard will be able to make you a carbon/Kevlar/GRP part if you don't have the equipment or desire to DIY and for much less cash than anywhere with the word motorsport in the name LOL.

[pete-r]

Not sure exactly but it seems ok on race cars and let's be honest, the clam doesn't melt or burn next to the manifold or tailpipes. If you want to put some heat reflective tape or nimbus on the top side that will no doubt sort it.

[Aerodynamic]

How does it work? Is the reflective tape reflect away the heat.

 

If I put a 1mm alu sheet on top this will distribute the hear and the big area will cool the heat off?

 

Br, Per

[pete-r]

Yes it reflects the heat away from the part covered. If you're worried about heat you could keep your oem diffuser and bolt the new one to it.

[FLD]

Just use heat resistant resin. There are various temp tolerances etc out there. Just make sure you get an ambient cure one.

[Doctor Ed]

yep, make a wooden buck, and then lay up a glass/carbon part. if you destroy it, youve got the buck and can make another

 

thats how ill be making mine