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Stiffen the unibody with polyurethane?
Posted: Sun Jul 23, 2006 7:54 pm
by donk_316
http://www.junauto.co.jp/products/reinf ... ex.html?en
Is there a normal verison of thos? can i buy it at home depot? haha! shh! maken drinks with alchohol! lmao! woo!
Posted: Sun Jul 23, 2006 7:56 pm
by Shaun41178(2)
I couldn't read that shit. Lost in translation anyone?
I think the only good way to stiffen a unibody is to weld the seems.
Posted: Sun Jul 23, 2006 7:58 pm
by donk_316
it sayd verry clearly
"
It is said that a too hard body is not good. A reason is for a maker to perform shock absorption considered for safety.
A body will transmit various information to each part, if rigidity improves. But if body reinforcement is actually performed, wages will become a large sum for reinforcing roll bar spot increase, reliance board reinforcement, etc.
Also it is difficult to imagine what effect it induces. Then, the epoch-making body reinforcement item which can be felt at low cost was developed.
This new reinforcement method makes high rigidity feel simply, so that it reverses old common sense. The car which performed urethane body reinforcement can feel the difference, when it get in and departs, you feel a motion of a car. The car which has constructed the roll cage etc. is still more effective. Although there is a difference in the ratio of an effect also by the new car or the old vehicle, rigidity is raised certainly."
duh!
Posted: Sun Jul 23, 2006 7:58 pm
by donk_316
all your bases are belong to us!
Posted: Sun Jul 23, 2006 8:32 pm
by p8ntman442
In my best warren G Voice. Moderators, MOUNT UP!
Posted: Sun Jul 23, 2006 8:36 pm
by donk_316
you gotta problem wid my japan spec chassis stiffener... speaking of asians stiffeners... you should SEE the whores in bangkok... wow!
Posted: Mon Jul 24, 2006 10:02 am
by Kohburn
didn't Will say that he used the spray foam from home depot in his frame rails..
it makes sense to me to fill the roll cage tubing with 2part expanding closed cell foam.. add minimal weight but a lot of additional crush resistance and vibration deadening
Posted: Mon Jul 24, 2006 5:04 pm
by The Dark Side of Will
Roll cage tubing is so thick that foam filling won't really matter.
The stuff they sell at HDR (Home Depot Racing) is so light that it won't significantly affect chassis stiffness. You need a much higher density of foam to have any effect on chassis stiffness.
Posted: Tue Jul 25, 2006 6:48 am
by rube
Posted: Tue Jul 25, 2006 7:47 am
by Kohburn
The Dark Side of Will wrote:Roll cage tubing is so thick that foam filling won't really matter.
The stuff they sell at HDR (Home Depot Racing) is so light that it won't significantly affect chassis stiffness. You need a much higher density of foam to have any effect on chassis stiffness.
the stuff at home depot requires air to cure also - so i don't even trust it inside an enclosed tube
Posted: Tue Jul 25, 2006 11:29 am
by The Dark Side of Will
It cures inside a big lump of itself.
Posted: Tue Jul 25, 2006 11:52 am
by Pyrthian
Kohburn wrote:didn't Will say that he used the spray foam from home depot in his frame rails..
ya dont want to fill something that may rust with this stuff. it WILL trap humidity & make it rot faster. it will not seal out water. but, if its well painted/protected (which is HARD to do inside of tubes & box rail) it will keep work OK, and keep dirt out & do some sound deadening.
also, hot spots from exhaust will make large bubbles which will trap humidity. this is NOT something you want to do to your engine cradle without LOTSA pre-cleaing/painting. maybe after a acid dip & enamel dip.
Posted: Tue Jul 25, 2006 11:58 am
by The Dark Side of Will
The 3M products are CLOSED CELL foam. They don't trap anything but whatever it is that makes them foam in the first place.
Posted: Tue Jul 25, 2006 12:07 pm
by Pyrthian
the cells themselves, yes
but, there are always gaps. I am not saying the stuff itself soaks water like a sponge. I am saying its more like a sheet of plastic on laying concrete. after its left there a few days, when you lift it up, its damp underneath. there will be air pockets and there will be expansion/compression. the insides of the box rail wont be able to dry out like if they were open air.
also, I dunno the heat resitance, but I expect the stuff will collapse near any exhaust.
but again, if painted/protected, it'll be fine
Posted: Tue Jul 25, 2006 12:09 pm
by Kohburn
The Dark Side of Will wrote:It cures inside a big lump of itself.
when I cut large lumps open i found the inner most air pockets to be very oversized and extremely soft - they also took several days to cure vs the outside that took hours
2-part expanding foam is seriously superior to the cans you get from home depot
you can get small quantities of 2part spray foam (mixes in the tip) from mcmaster
Posted: Thu Jul 27, 2006 5:04 pm
by DreX
Some time ago I read in a magazine a way to stiff the chasis with a foam. Dont remember the brand tho. Anyway, I was thinking to do something like that for a long time now. Will be good to see where this topic ends.
Good job, keep the brain cells on guys.
DreX
Posted: Thu Aug 31, 2006 9:08 pm
by The Dark Side of Will
Kohburn wrote:The Dark Side of Will wrote:It cures inside a big lump of itself.
when I cut large lumps open i found the inner most air pockets to be very oversized and extremely soft - they also took several days to cure vs the outside that took hours
2-part expanding foam is seriously superior to the cans you get from home depot
you can get small quantities of 2part spray foam (mixes in the tip) from mcmaster
What page, or what product?
Posted: Thu Aug 31, 2006 10:13 pm
by stimpy
The Ford Truck "Quiet Steel" is essentially this stuff.
Posted: Sat Sep 23, 2006 7:57 pm
by donk_316
Any one figure out what this stuff is? I pulled my door sills and there is foam inside them already
Posted: Thu Mar 15, 2007 7:40 am
by Kohburn
just requires a 2part expanding foam rather than a 1part like the foam cans at home depot. I now have an expanding foam mixer for spraying insulation, could easily spray it inside a frame rail.
I can get closed cell foam in densities from 1.7 lb per cubic foot to 3 lb per cubic foot.
the 1.7# is strong enough to walk on - the 3# is rated for use as a roofing material it is so hard.
you can get small amounts of 1.7-2# foam from little kits like...
http://loyola-1.stores.yahoo.net/frpk180.html
can get 3# from here
http://www.intechequip.com/frothpak.htm
these kits don't need any additional in order to use, they come with hose and nozzles.