anyone know much about sandwich panles?
apparently the sides of artic truck trailers are made of the stuff, but not sure how thick - and hence string. been googling and theres a bunch out there - either foam innards of honeycomb.
basic plan is to make a sort of monocoque/box chassis out of the stuff for my next project. should be stiff as hell and light too. recon its also pretty suited to a 7 stly car due to design of 7 chassis - mainly flat sides.
also, anyone know here i can get large sheets of carbdboard honeycomb from? checked packing places but not sold by te sheet, but seen it so know its out there. easy and cheap way to prototype methinks.
anyway - anyone out there been there, done that or in the industry?
cheers,
zane

I remember two racing car made using such techniques.

First - the old vauxhall lotus chassis use aluminium/kevlar planks. Dermot Healy may be able to supply some of these.

Second - The ex Lola designer Ben Bowlby built a Clubmans car as part of his degree course. This car was unique for the time in that it used a similar technique when everyone else was still building spacframes.

Really - what your talking about is actually 70s single seater technology.
Caterham also use honeycomb for side panels after some high profile accidents in the 90s IIRC.

this might be of interest to you, its a Strathcarron. I thik they have gone bust now.
Rescued attachment 2923-06.jpg

and this
Rescued attachment 2923-05.jpg

when built, looks like this
Rescued attachment 2923-01.jpg

this guy: http://www.geocities.com/MotorCity/7630/index.html
built a seven style car using foam filled aluminium sandwich panels - he claims 9000Nm per degree torsion (pretty stiff)

wow, thanks a lot guys. knew it had been done before but not much more. def had no idea the strathcaron was build this way - great pictures jon. always liked that car. thats pretty much exaclty what i had in mind. looks pretty doable - will look into prices etc now, check feasability from that end.
cheers for input, will keep you posted on project.

If you find out how to work with this material, please tell us - how do you join two bits such that the join is strong ?

Years ago I was lent a copy of Carol Smith's Prepare to Win. I read it cover to cover in one go (it was that good). I think there was a short section in there about this stuf.

i have that book! ill give it a bedtime perusal. theres quite a bit on fastners which go through or embed themselves in the material. the ali honeycomb gets used as aeroplane folloring so i guess someone has developed some pretty strong fixings. ive been working on some other fixing methods but no point re-inventing the wheel. scoring and bonding also seems a favorite. remember a sales pitch once from vantico, who make areldite, concerning a helicopter seat for the mod made from a single sheet, folded to make a pretty darn rigid form and glued together. elise is bonded so think it may have some potential.
really want to work in card first as should be cheap and easy to work with scissors and tape, hope that a well designed box section will have a lot of inherent strength. still cant find a card honeycomb supllier but will start on plain card scale model next week. more as it happens...

I used to work with aluminium honeycomb sandwich panels.
Flat panels are usually bonded in a platen press. These can be hydraulic, basically two flat surfaces pushed together under hydraulic pressure, with the sandwich panel between. They can also be vacuum where the sandwich panel is placed on a flat surface and a neoprene or similar sheet in a frame is clamped over it and has all the air sucked out. More complex shapes can be created using formers and vacuum bags.
The sandwich is bonded using adhesives. In the case of aluminium the strongest bonds are created using sheet epoxy adhesives although these are quite expensive and require to be held under pressure throughout a heating/curing cycle of circa 1-2hours at 250 C.
2 part Polyurethane adhesives can also be used and are usually sprayed on, although they can be applied with a brush and have an "open time". These can be cured at room temperature.
Application of pressure during curing is the critical factor as the finished sandwich acts as a beam. Without a solid intimate bond it doesn't work.
Honeycomb is usually supplied in cut blocks which are then expanded to full size.
Try www.hexcelcomposites.com
If the won't supply you with any they should be able to put you in touch with a company local to you that they do supply.
I used to deal with another company but can't remember their name. If it comes to me I'll post it.

Best place to start looking for cardboard honeycomb are internal door manufacturers. They use loads of it.

By the way to have two sheets of say 1.0mm Aluminium commercially bonded each side of a 12mm thick x 12mm cell aluminium honecomb would cost in the region of £80-£100 excluding the cost of the aluminium sheets.

Hope this helps,

David

I believe this stuff is called alucore if anyone wants to do a search,

The Strathcarron was borrowed/pinched/bought by Marlin for the 5EXi, though they use a (not very strong looking) tubular chassis rather than the monocoque.