Filling the chassis voids

[Renato]

Is anyone filling the voids between two aluminum panels with something. My wheel wells and some other areas have panels on both sides with about 1.5 inches of space in between. My double firewall is getting hi temp heat insulation so I'm not worried there.

I'm considering filling them with something, not sure what. Maybe just sound deadening sheet on both sides or expanding foam or both maybe?

Did a test with two component expanding foam and it does a nice job of filling the void between two sheets, but I'm a bit worried about the durability of the foam.

Any experience or thoughts?

Renato

 

[Doc Watson]

I read a discussion about filling a steel inner and outer roof on a mono chassis with expanding foam, not sure if it happened though. If memory serves I think the plan was to drill a few 'release holes' to allow the foam tube access to all the areas and more importantly to allow excess foam out. The main concern was the foam could distort the sheeting that contains it if you put to much in.

If you still have not attached the skin and have access to the areas then you can use builders insulation foam 'celotex' is a brand here in the UK and/or you could add sound deadening sheet. I would try a test piece if using the expanding foam.

Anybody else got any thoughts?

 

[Renato]

I know Tom (EGLITOM) filled his RCR spyder with two component expanding foam successfully. I am thinking of doing the same on mine.
I haven't found anyone filling voids between aluminum panels.

Regards,
Renato

 

[Phil]

Renato:
I filled the areas adjacent to the cabin ( between cabin and fuel tanks) which is a 1 1/2" space with ceramic insulation. I haven't yet gotten to the inner panelling I want to do in the footwell etc., but I think the expanding foam is a good idea as long as Doc mentioned it is vented, that stuff can really push out panels if not.
The only issue I have with some of the foams is their flammability, and I honestly don't know if there is one on the market that is flame retardant.
Maybe some others here have knowledge of other products.
Cheers
Phil

 

[Darrin]

I've been thinking about doing that as well. Any reason you are going with a two part solution? I see this stuff having a -200 to +240 temp range, insulates at R5, and is cheap!

http://www.zorotools.com/g/00064695/k-G2892434?utm_source=google_shopping&utm_medium=cpc&utm_campaign=Google_Shopping_Feed&kw={keyword}&gclid=CNCZlIzSjLYCFW2nPAodcG0AWw

 

[Andy Green]

Renato,
I filled the double skinned areas around the front panels with Rockwool (a fibre-glass loft insulation in the UK). It will help damp any panel vibration and reduce the noise transmission from the road/wheel. It's extremely light, so it was a no-brainer really.
Regards,
Andy

 

[Dylan]

There are sound-deadening thick foam rolls available from a number of suppliers, including flame-retardant ones. I have used this before with success in replacing insulation and creating new sound deadening in doors/kickpanels of classic cars. Cutting these to size and applying to the panels with an adhesive would be a lot less messy than expanding foam, and probably more effective than fiberglass insulation. (Though I only have been able to compare it to 40 year old fiberglass car insulation, so who knows how much better it is than new stuff). At least you wouldn't have to take a shower after you worked with it.

 

[Fred W Ballinger]

filled the double skinned areas around the front panels with Rockwool

Andy, not to offend but I would not use a Rockwool type product in this application as:

- Rockwool if not tightly packed or otherwise secured will eventually "shake down"
- If you have any water intrusion in the compartment the wool soaks up the water and retains it.

The above is experience gained in an insulated transport container industry.

To the OP, if the motivation for the fill is to make the panel feel solid, and add insulation expanding foam would be a good solution, as long as it it closed cell foam. The product sold in cans in hardware stores for filling around pipes etc in holes in building is not closed cell.

Fred W B

 

[EGLITOM]

This is the product i´ve used.
Nos produits - Sicomin.com

it is from yacht builders supply. I did use the PB250 ( 250 gramms/liter) and would recommend to use the PB170 next time.

This 2K foam has a quicker expansion than hardening curve and therefore does not build up high pressures as long there are overflow openings. Once hardened it can be machined ( the 600g version is realy strong).
It is not waterwicking and available in a fireretartend selfextinguishing version (PB270I) as well.

TOM

 

[Doug S.]

I read a discussion about filling a steel inner and outer roof on a mono chassis with expanding foam, not sure if it happened though. If memory serves I think the plan was to drill a few 'release holes' to allow the foam tube access to all the areas and more importantly to allow excess foam out. The main concern was the foam could distort the sheeting that contains it if you put to much in.

Anybody else got any thoughts?

Go to a hardware store and buy "minimally expanding" foam. It is designed to put into voids around doors and windows where you don't want the foam expanding to the degree that it displaces the frames and causes the door or window to bind.

Cheers!

Doug

 

[Renato]

I did a test with Aeromarine product. It's a two component closed cell rigid foam used in aircraft and boats. It's 2 LBS density foam and very rigid. Made a "u" shape channel from aluminum and filled it with foam. Felt very strong after the foam cured. My only concern would be flammability and degradation of the foam.

[ame=http://www.amazon.com/gp/product/B0047R4AQW/ref=oh_details_o04_s00_i00?ie=UTF8&psc=1]Pourable Flotation and Insulation Foam, Closed Cell Rigid Foam - Amazon.com[/ame]


Renato

 

[Renato]

Tom,

Thanks for the info, very nice product.
Found the US distributor:

Sicomin Foaming Epoxy: Core Composites, Inc.

Renato