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Ally Honeycomb
43655 - 14/12/13 at 11:04 AM

Has anyone else used this stuff before structurally?
Fella in work used to work on the stuff and just a cardboard sandwiched honeycomb took a ton load in the centre of a m^2 panel to fail.
Basically considering it for the floor of my project so i can limit it to perhaps just 2 beams across (under the seats probably)
Or is the floor of a chassis likely to be susceptible to side loading, keeping the tunnel and side beams in place basically?


ere's an oldish model of the chassis to illustrate what i had (crossed beams in 30x30 to carry load of it getting stood on etc, and ally sheet top and bottom)



Slightly off-topic, but aluminium sheet riveted to structural tubes provides a noticeable stiffness increase surely? Asking purely for the tunnel and side bars


richardm6994 - 14/12/13 at 11:15 AM

cardboard honeycomb? I know the stuff you mean and it is dead strong...but only when dry.

I'd suspect in your situation it may get wet and even if you did a good job of sealing it in between the ally panels....it could still condensate between the panels??

I'm no expect but that's the first thing that sprang to mind after reading your post.


Theshed - 14/12/13 at 11:44 AM

Used it structurally.....yes!

Pasenger footwell complete
Pasenger footwell complete


You can get many cores. Making your own aluminium core is a bit tricky - its moderately expensive to buy.

How about thin ally/foam/thin ally - easy to make at home.


Theshed - 14/12/13 at 12:00 PM

Just to add...I doubt you would need crossed beams and a sandwich panel. A panel would be very stiff if properly attached to the surrounding tubes. You could rivet, bond, bond and rivet, or bolt in with the use of inserts.


Volvorsport - 14/12/13 at 02:08 PM

make the whole car out of it ....?

teklam.com


iank - 14/12/13 at 02:26 PM

Article on the possibility of using cardboard honeycomb http://www.autospeed.com/cms/A_112917/article.html
and a How-to for aluminium honeycomb (for a monocoque) http://www.autospeed.com/cms/A_112925/article.html


43655 - 14/12/13 at 03:14 PM

quote:
Originally posted by richardm6994
cardboard honeycomb? I know the stuff you mean and it is dead strong...but only when dry.


ha ha noo, that was just an example as it was what was mentioned, i know it'd be silly in a car!

It would definitely be aluminium. It's not all that expensive to buy, i think for 2 floor panels it was £150 or thereabouts, which for the strength:weight is worth it I'd say.
Couldn't seem to find much that was pre-bonded to the honeycomb, as that's where the strength is.

Not sure if foam has the same rigidity?
Plus it's horrible stuff! Spent days and days fighting with the stuff making wide arches on my car in the end i've gone to just using sheet steel for the plug.

I'd still want to have the seats attached to steel crossbeams, but on theory the ally's strength will mean i don't need the X's that i'd previously drawn in.

threshed, that's pretty impressive! I take it that's a monocoque chassis?


Volvorsport - 14/12/13 at 03:49 PM

have a look at the teklam site , they have lots of choice .

other suppliers in the uk could be HGV/coachbuilders who make bodys out of the stuff .


davidimurray - 14/12/13 at 04:05 PM

Used all the time to build Formula Student/FSAE cars - we built 5 or 6 single seaters using it. Nice and simple to glue up a tub but then needs proper machined inserts for bolting through, load spreading plates etc etc. Would be fine to use for a floor and if you bond in will add stiffness.


scimjim - 14/12/13 at 04:52 PM

used extensively in the aircraft world - look up NIDA honeycomb. Very good strength/weight but the point loading is only as good as the outer skin (eg poor when used as a floor) so usually has a sacrificial ply freight floor on top.