Do you remember that structual foam? S.C.C. mag June 2000. Did anyone ever try it?
Thread Starter
Honda-Tech Member
Joined: Jan 2001
Posts: 908
Likes: 0
From: RICHMOND, VA, USA
Do you remember that structual foam? S.C.C. mag June 2000. Did anyone ever try it?
It was used to help strengthen the chassis in a 300zx I dont think it would be legal in any race class In local level auto-x 
and daily driving, It could help wet noodle vehicles like my Delsol. Any thoughts?
Here is the link.
http://www.itwfoamseal.com/auto_aftermarket.htm
and daily driving, It could help wet noodle vehicles like my Delsol. Any thoughts?Here is the link.
http://www.itwfoamseal.com/auto_aftermarket.htm
Joined: Jan 2002
Posts: 4,931
Likes: 0
From: formerly elgorey, VIRginia
Re: Do you remember that structual foam? S.C.C. mag June 2000. Did anyone ever try it? (SoloSol)
I personally dont think of 'foam' and 'structurally rigid' to be synonymous.
IMO, any improvements would be perceived but not actual, as the foam would insulate sounds and vibrations of a noodley chassis.
just my un-informed opinion
IMO, any improvements would be perceived but not actual, as the foam would insulate sounds and vibrations of a noodley chassis.
just my un-informed opinion
Honda-Tech Member
Joined: Jun 2002
Posts: 1,149
Likes: 0
From: Toronto, On, Canada
Re: Do you remember that structual foam? S.C.C. mag June 2000. Did anyone ever try it? (SoloSol)
Finally, i have been trying to rember the company for a while now
i too whould like to know what other popel think?
i too whould like to know what other popel think?
Honda-Tech Member
Joined: Jul 2002
Posts: 502
Likes: 0
From: Fresno, CA, USA
Re: Do you remember that structual foam? S.C.C. mag June 2000. Did anyone ever try it? (elgorey)
I personally dont think of 'foam' and 'structurally rigid' to be synonymous.
IMO, any improvements would be perceived but not actual, as the foam would insulate sounds and vibrations of a noodley chassis.
just my un-informed opinion
IMO, any improvements would be perceived but not actual, as the foam would insulate sounds and vibrations of a noodley chassis.
just my un-informed opinion
Try this for an informed opinion:
From the SCC article on the 300ZX
Foam-Filling the Chassis
In any high-performance car, it is impossible to make the chassis too stiff. The stiffer the chassis, the higher its natural frequency, making the energy imparted to it by bumps less likely to excite the body's structure. A stiffer chassis enables the use of stiffer springs and shocks without hurting the ride. This is because a stiff, non-flexing chassis transfers more force into the suspension where it can be dissipated by the springs and shocks instead of transferring the force to the occupants. A stiff chassis is also more responsive to roll rate tuning for balancing understeer and oversteer. This is one of the reasons why automotive engineers are continually investigating ways to stiffen chassis without adding weight.
In a final bit of reengineering to stiffen the body, we injected the chassis with catalyzed rigid structural polyurethane foam. Structural foam, in the 2 lb per cubic foot density that we used, can stiffen chassis members up to 40 percent.
Higher densities of foam can increase stiffness by up to 300 percent. Since we cannot retool custom parts to redo the Z's body, we figured that this would be an excellent, low-cost way of greatly increasing chassis stiffness. Injecting foam is not a new technique for chassis stiffening. The Infiniti Q45 uses this sort of foam in some of its chassis members to increase stiffness, as do a few other premium cars. In fact, the foam we chose is the foam recommended to repair damaged Q45s.
To get the correct foam for our project, we contacted Art Goldman, Foamseal's automotive product manager and author of an SAE (Society of Automotive Engineers) paper on the use of structural foam for the stiffening of automotive unibody structures. We used Foamseal's two-component foam kit, p/n 11-22 to fill the main members of the chassis. Like we mentioned earlier, Foamseal is the supplier that I-CAR, a national certification group for quality auto repair, recommends for the repair of damaged, foam-filled chassis. The Foamseal kit uses a two-part catalyzed polyurethane foam, which quickly cures into rigid, waterproof, closed-cell foam. To prep the car, we carefully masked off all painted areas anywhere where the foam could drip. As this sort of foam is a thermosetting catalyzed plastic, we realized it could be icky if it spilled on paint or any part of the car's interior. This foam is nasty stuff. It is impervious to all known solvents and cleaners.
Rubber gloves must be worn. Get some of it on your hands and it will stay there for more than 3 weeks--don't ask how we know. Do not get this stuff on your paint. Wear old clothes; we ruined ours while learning how to handle the product. We injected the foam into the rocker panels and frame rails of Project Z through existing bolt and drain holes. When injected, the foam reacts like shaving cream and quickly expands to fill the empty space. You can judge how much foam to add by watching its expansion progress through some of the holes. Once injected, the foam expands and begins to cure in about a minute so you need to work fast and plan how you inject the foam before you start.
The life of the foam kit is limited to a few hours once the seal is broken. We filled all of the Z's unibody frame members using five foam kits. When foaming a chassis, you must remember the wires and other lines that pass through the chassis must be relocated or they will be entombed forever.
We were amazed at how this simple procedure improved the performance of the car. The chassis now almost feels like it has a roll cage. A sloped driveway can be driven up sideways with nary a creak. Even though the Z already has a pretty tight chassis, it feels more solid. The ride has improved and road noise has been reduced noticeably. We bet that the car will be even more responsive to chassis tuning measures in the future. If you are a slalom racer, a road racer, have a lowered car or even just want a smoother ride; foaming is a worthy, easy-to-do modification. Foamseal has foams in densities as high as 10 lbs per square foot if you desire to make things even stiffer.
Do not--I repeat--do not attempt to use cheap, hardware-store canned foam. This is not the same thing, and if injected into your chassis, will form a gummy mass that won't dry. Foamseal foam is a professional grade foam, which although it is a little unforgiving to cleanup mistakes, has superior mechanical properties and catalytic curing so it will dry even in an enclosed space.[/b]
In any high-performance car, it is impossible to make the chassis too stiff. The stiffer the chassis, the higher its natural frequency, making the energy imparted to it by bumps less likely to excite the body's structure. A stiffer chassis enables the use of stiffer springs and shocks without hurting the ride. This is because a stiff, non-flexing chassis transfers more force into the suspension where it can be dissipated by the springs and shocks instead of transferring the force to the occupants. A stiff chassis is also more responsive to roll rate tuning for balancing understeer and oversteer. This is one of the reasons why automotive engineers are continually investigating ways to stiffen chassis without adding weight.
In a final bit of reengineering to stiffen the body, we injected the chassis with catalyzed rigid structural polyurethane foam. Structural foam, in the 2 lb per cubic foot density that we used, can stiffen chassis members up to 40 percent.
Higher densities of foam can increase stiffness by up to 300 percent. Since we cannot retool custom parts to redo the Z's body, we figured that this would be an excellent, low-cost way of greatly increasing chassis stiffness. Injecting foam is not a new technique for chassis stiffening. The Infiniti Q45 uses this sort of foam in some of its chassis members to increase stiffness, as do a few other premium cars. In fact, the foam we chose is the foam recommended to repair damaged Q45s.
To get the correct foam for our project, we contacted Art Goldman, Foamseal's automotive product manager and author of an SAE (Society of Automotive Engineers) paper on the use of structural foam for the stiffening of automotive unibody structures. We used Foamseal's two-component foam kit, p/n 11-22 to fill the main members of the chassis. Like we mentioned earlier, Foamseal is the supplier that I-CAR, a national certification group for quality auto repair, recommends for the repair of damaged, foam-filled chassis. The Foamseal kit uses a two-part catalyzed polyurethane foam, which quickly cures into rigid, waterproof, closed-cell foam. To prep the car, we carefully masked off all painted areas anywhere where the foam could drip. As this sort of foam is a thermosetting catalyzed plastic, we realized it could be icky if it spilled on paint or any part of the car's interior. This foam is nasty stuff. It is impervious to all known solvents and cleaners.
Rubber gloves must be worn. Get some of it on your hands and it will stay there for more than 3 weeks--don't ask how we know. Do not get this stuff on your paint. Wear old clothes; we ruined ours while learning how to handle the product. We injected the foam into the rocker panels and frame rails of Project Z through existing bolt and drain holes. When injected, the foam reacts like shaving cream and quickly expands to fill the empty space. You can judge how much foam to add by watching its expansion progress through some of the holes. Once injected, the foam expands and begins to cure in about a minute so you need to work fast and plan how you inject the foam before you start.
The life of the foam kit is limited to a few hours once the seal is broken. We filled all of the Z's unibody frame members using five foam kits. When foaming a chassis, you must remember the wires and other lines that pass through the chassis must be relocated or they will be entombed forever.
We were amazed at how this simple procedure improved the performance of the car. The chassis now almost feels like it has a roll cage. A sloped driveway can be driven up sideways with nary a creak. Even though the Z already has a pretty tight chassis, it feels more solid. The ride has improved and road noise has been reduced noticeably. We bet that the car will be even more responsive to chassis tuning measures in the future. If you are a slalom racer, a road racer, have a lowered car or even just want a smoother ride; foaming is a worthy, easy-to-do modification. Foamseal has foams in densities as high as 10 lbs per square foot if you desire to make things even stiffer.
Do not--I repeat--do not attempt to use cheap, hardware-store canned foam. This is not the same thing, and if injected into your chassis, will form a gummy mass that won't dry. Foamseal foam is a professional grade foam, which although it is a little unforgiving to cleanup mistakes, has superior mechanical properties and catalytic curing so it will dry even in an enclosed space.[/b]
I think I might do this...
[Modified by Mojo-Jojo, 1:38 PM 10/1/2002]
Junior Member
Joined: Nov 2001
Posts: 876
Likes: 0
From: Longmont, CO, USA
Re: Do you remember that structual foam? S.C.C. mag June 2000. Did anyone ever try it? (Mojo-Jojo)
Interesting......but where would you "squirt" it into on a unibody vehicle? In crevices? Are there that many hollow chambers in the unibody? What about the "horror stories" of people using similar products and popping off body panels/splitting seams when the foam expands?
Steve
Steve
Joined: Jan 2002
Posts: 4,931
Likes: 0
From: formerly elgorey, VIRginia
Re: Do you remember that structual foam? S.C.C. mag June 2000. Did anyone ever try it? (Mojo-Jojo)
You're wrong. They're real improvements.
Try this for an informed opinion:
From the SCC article on the 300ZX
First of all, I didnt claim to be right, only the concept of the idea has flaws and not exactly intuitive.
Second of all, quoting a riceboy magazine one step up from Super Street does not make for proof. That article has absolutely no quantitative results and actually backs up what I was saying with its lack of it.
The Infiniti Q45 uses this sort of foam in some of its chassis members to increase stiffness, as do a few other premium cars
The chassis now almost feels like it has a roll cage. A sloped driveway can be driven up sideways with nary a creak
The ride has improved and road noise has been reduced noticeably.
The SCC article is worthless. dont quote it, and dont even try to pass it off as fact.
Now, having dispelled the bullshit, here is my personal view on the subject.
The idea does have some bit of merit because, the basic concept is that you are taking something that used to be air, and filling it with something stiffer than air. so technically there will be some degree of improvement. How much? who knows, the SCC article certainly didnt provide any numbers to back it up. But take into account what foam is: plastic with a lot of air mixed in. would you run a plastic strut bar? a foam strut bar? hahahah
In my opinion, the foam would not have enough structural integrity to seriously withstand the extreme twisting forces generated on the chassis. Think about it, all that force is enough to twist very thick, very strong metal. Is some foam going to be able to put a serious dent in that force?
I dont think so, and until some chassis stiffness tests are done Im not going to believe some magazine article based on how the car rides good and doesnt squeak afterwards.
[Modified by elgorey, 6:07 PM 10/1/2002]
Trending Topics
Honda-Tech Member
Joined: Dec 2001
Posts: 4,035
Likes: 0
From: Greensboro, NC, USA
Re: Do you remember that structual foam? S.C.C. mag June 2000. Did anyone ever try it? (SoloSol)
Even without any empirical data from the "test" cited, it could make a difference in theory. Assuming that the foam bonds to the sheetmetal, it would be like corrugating cardboard. Foam has been used in structures like waterskis and interior panels for aircraft for decades, and I have even seen experiments using foamed concrete elements for building construction.
HOWEVER, it doesn't make any damned sense to do it, in the context of any of the (sane and/or legal) uses of the cars we talk about around here.
It's not allowed under any race sanctioning body that I know of (I would hate to think about the toxic smeg that it would produce in a fire) and I am having a difficult time understanding why anyone needs a stiffer-than-stock chassis on a street car. The same issue has come up once ever other week where seam welding is concerned and OMFG, please let's not revisit the strut bar conversation again.
If a DelSol is too squishy, buy a Civic coupe. If a Civic is too squishy, don't put whopping great springs on it or run it on the 'stops. If you must have stiff springs, build a racing car and follow the rules.
So there you go.
Kirk
PS - I mentioned this the last time this came up but a reefer car (that's trains, Beevis) manufacturer in Seattle put on a demo of foaming the gaps in the corrugated steel of a boxcar, for a bunch of big-wigs. They pumped in a bunch of the same kind of stuff mentioned in the article - and were a little embarrassed when the train car unzipped at the seams when it expanded. Poing! Seems they forgot to put in holes to allow for overflow as the stuff's volume expanded...
HOWEVER, it doesn't make any damned sense to do it, in the context of any of the (sane and/or legal) uses of the cars we talk about around here.
It's not allowed under any race sanctioning body that I know of (I would hate to think about the toxic smeg that it would produce in a fire) and I am having a difficult time understanding why anyone needs a stiffer-than-stock chassis on a street car. The same issue has come up once ever other week where seam welding is concerned and OMFG, please let's not revisit the strut bar conversation again.
If a DelSol is too squishy, buy a Civic coupe. If a Civic is too squishy, don't put whopping great springs on it or run it on the 'stops. If you must have stiff springs, build a racing car and follow the rules.
So there you go.
Kirk
PS - I mentioned this the last time this came up but a reefer car (that's trains, Beevis) manufacturer in Seattle put on a demo of foaming the gaps in the corrugated steel of a boxcar, for a bunch of big-wigs. They pumped in a bunch of the same kind of stuff mentioned in the article - and were a little embarrassed when the train car unzipped at the seams when it expanded. Poing! Seems they forgot to put in holes to allow for overflow as the stuff's volume expanded...
Honda-Tech Member
Joined: Jan 2000
Posts: 1,535
Likes: 0
From: San Diego, CA 92104
Re: Do you remember that structual foam? S.C.C. mag June 2000. Did anyone ever try it? (Knestis)
I believe it's the same idea if not the exact same thing, but I was watching a Japanese video of a competition of different tuners for Skyline GTR's. One of the shops that brought their car did this. They drilled holes along the body where they filled them up with this stuff. It significantly improved the cars handling. If I remember correctly, the race car drivers who drove it said it handled the best out of all the other tuner shops' skylines. Just a thought to consider
Honda-Tech Member
Joined: Jul 2001
Posts: 1,944
Likes: 0
From: ny/me, usa
Re: Do you remember that structual foam? S.C.C. mag June 2000. Did anyone ever try it? (2000Accord5s
ahh firstly scc= sport compact car, not super street
Second SCC articles arent always correct either
I feel it may help in Harmonic dampening of the chassis but actualy stiffness would be limited in this case. Polymers are generally very weak and have a very plyable structure. They also dont handle well under loads and are not uniform whatsoever. I would be interested in getting the article number of this SAE article, I am a member of SAE and would glady read it up and report back to you guys
Second SCC articles arent always correct either
I feel it may help in Harmonic dampening of the chassis but actualy stiffness would be limited in this case. Polymers are generally very weak and have a very plyable structure. They also dont handle well under loads and are not uniform whatsoever. I would be interested in getting the article number of this SAE article, I am a member of SAE and would glady read it up and report back to you guys
Good, Bad…I'm the one with the gun
Joined: Jul 2002
Posts: 5,241
Likes: 2
From: Trapped in time, Surrounded by evil, Low on gas
Re: Do you remember that structual foam? S.C.C. mag June 2000. Did anyone ever try it? (Knestis)
...Foam has been used in structures like waterskis and interior panels for aircraft for decades...
let me inject some of my somewhat educated opinion. i have been involved in manufacturing composite small performance aircrafts some time ago. we used high density lightweight foam encased in either fiberglass, carbon fiber, kevlar or the combination of all. and forgive me for being hazy, but i haven't worked on the stuff for almost 10 years now, but without the foam, the integrity of the structural chassis will be laughable. as it stands the plane can withstand 9+G. mind you, the tanks are located in the wings, encased in the foam, wings have no structural beams less the foam and the 1/8 inch skin, mostly fiberglass and kevlar (for protection incase of forced landing). and let me tell you, we pushed the plane to it's limits (one pilot lost his life in a high G maneuver, blacked out without the use of the G-suit). structural foam works. it most likely is more effecient than a cage. the forces a good high quality structural foam can withstand are great, much more than say, a similar shape made of metal sheets. the combination of the skin (in the case of the airplane, it's the fiberglass, and the car it's the body panels) and the foam will make up a solid, rigid form, as if one would make of solid metal, more stable and LIGHTER.
the only difference in the foam characteristics were that the proposed foam is molded in the cavities and the kind we used (mostly) was block, precured foam, but i see no difference.
the choice of the foam is imperative. and the article does stress that. seems VERY sound to me.
that is my 2 cents
stan
P.S. another very important point to consider is that the foam needs to bind to the metal in order to properly function.
[Modified by 90crxsi, 7:18 PM 10/3/2002]
[Modified by 90crxsi, 7:18 PM 10/3/2002]
Honda-Tech Member
Joined: Jul 2001
Posts: 1,944
Likes: 0
From: ny/me, usa
Re: Do you remember that structual foam? S.C.C. mag June 2000. Did anyone ever try it? (90crxsi)
dont forget one thing to remember
the strength from composites come from the fibers (fiberglass Carbon Fiber), the polymers allow for ductility and make for better stress strain relationship (rather than yielding and becomming brittle they have a elastic relationship)
so the foam in the car really doesnt do all that much
the strength from composites come from the fibers (fiberglass Carbon Fiber), the polymers allow for ductility and make for better stress strain relationship (rather than yielding and becomming brittle they have a elastic relationship)
so the foam in the car really doesnt do all that much
Junior Member
Joined: Jul 2001
Posts: 274
Likes: 0
From: gone to the track or rally
Re: Do you remember that structual foam? S.C.C. mag June 2000. Did anyone ever try it? (90crxsi)
As you said, foam is used in many applications - surfboards, skis, etc. that require lightweight stiff structures. I make no claims here but it is a valid concept for chassis stiffening.
Honda-Tech Member
Joined: Jul 2002
Posts: 502
Likes: 0
From: Fresno, CA, USA
Re: Do you remember that structual foam? S.C.C. mag June 2000. Did anyone ever try it? (Audipwr1)
dont forget one thing to remember
the strength from composites come from the fibers (fiberglass Carbon Fiber), the polymers allow for ductility and make for better stress strain relationship (rather than yielding and becomming brittle they have a elastic relationship)
so the foam in the car really doesnt do all that much
the strength from composites come from the fibers (fiberglass Carbon Fiber), the polymers allow for ductility and make for better stress strain relationship (rather than yielding and becomming brittle they have a elastic relationship)
so the foam in the car really doesnt do all that much
Now, you guys know how there are lots of different kinds of plastic?
Some that are soft and squishy, and some that are hard and stiff?
Don't you think that it might follow that the catalyzed foam this place sells for chassis STIFFENING is probably of a pretty stiff variety of polymer?
It sounds like a few of you don't have room in your heads for different types of materials that are the same "stuff."
You guys don't think the ceramic heat shield tiles on the space shuttles are the same type of ceramic that a pot or plate or something is made out of do you?
[Modified by Mojo-Jojo, 12:46 AM 10/4/2002]
Banned
Joined: Mar 2001
Posts: 2,637
Likes: 0
From: at last finally back to sweet home, sunny north cali, usa
Re: Do you remember that structual foam? S.C.C. mag June 2000. Did anyone ever try it? (90crxsi)
delsol is not bad with hard top in place. i don't even have front and rear bumper beams in my car. took 'em out about 40k miles ago. car has not made any additional noise. chassis/motor just passed 100k miles yesterday on track.
thanks for your informed input stan. i wonder, those carbon fiber bicycle frames. if they have tried to inject foam in them...
thanks for your informed input stan. i wonder, those carbon fiber bicycle frames. if they have tried to inject foam in them...
Banned
Joined: Mar 2001
Posts: 2,637
Likes: 0
From: at last finally back to sweet home, sunny north cali, usa
Re: Do you remember that structual foam? S.C.C. mag June 2000. Did anyone ever try it? (elgorey)
I personally dont think of 'foam' and 'structurally rigid' to be synonymous.
IMO, any improvements would be perceived but not actual, as the foam would insulate sounds and vibrations of a noodley chassis.
just my un-informed opinion.
IMO, any improvements would be perceived but not actual, as the foam would insulate sounds and vibrations of a noodley chassis.
just my un-informed opinion.
Good, Bad…I'm the one with the gun
Joined: Jul 2002
Posts: 5,241
Likes: 2
From: Trapped in time, Surrounded by evil, Low on gas
Re: Do you remember that structual foam? S.C.C. mag June 2000. Did anyone ever try it? (Audipwr1)
i don't know about you, but when i look at an airfoil, i see and feel a very sturdy, non-flexing structure. although fiberglass, CF and kevlar are considered soft material, their only strength lies in lateral axis. they resist tear and stretch very well, thus the use of them in body armour. combined with polymer (resins) they bind, creating a verry brittle shell-like form. the foam inside adds the necessary rigidity to the whole thing, otherwise the composite will shatter, just ask anyone with a CF hood, especially a dry fiber one. provided you BIND the foam to the metal, it will restrict panel to panel movement, adding another plane of rigidity. a hollow, empty volume, unless it is a certain shape will collaps if the forces are applied to it from the outside, the foam adds that resistance to it.
i think i am repeating myself. in any case, if only for the sound isolation reasons, i will do it.
stan
i think i am repeating myself. in any case, if only for the sound isolation reasons, i will do it.
stan
Good, Bad…I'm the one with the gun
Joined: Jul 2002
Posts: 5,241
Likes: 2
From: Trapped in time, Surrounded by evil, Low on gas
Re: Do you remember that structual foam? S.C.C. mag June 2000. Did anyone ever try it? (ghettoRacer)
one more post, i think most people have a missconception on the type of foam used. it is VERY dense. not your garden variety packing foam. expencive too.
stan
stan
Honda-Tech Member
Joined: Apr 2002
Posts: 18,961
Likes: 75
From: I am Tyson
Re: Do you remember that structual foam? S.C.C. mag June 2000. Did anyone ever try it? (90crxsi)
I saw SCC in the title of this thread and didnt bother reading it til now. Did a little search and got this, an explanation of how and WHY a manufacturer uses structural foam in their product. I think there are some key points in here that validate some of the pros and cons of automobile chassis use. Based on this, it seems some ppl have made intelligent comments, some have just been ignorant...
Injecting the foam
by Stefano Fedeli
“My job at Bianchi is to inject our revolutionary Structural Foam into the frames. This is a fairly easy job, not least because the foam is not toxic in any way. The process of injection occurs after the painting, clearcoat, decal application and final check of the frame. This is because if the painting of the frame failed quality control and we had to strip it and re-paint it, the paint stripping acid would react with the foam, effectively neutralising it.
I use a large syringe, powered by compressed air, with a 90º curved pipe at the end which can be easily inserted into the opening between the bottom bracket and the seat tube. With this instrument, a controlled dosage of 50ml is injected into the bottom of the seat tube. The foam immediately expands to a height of 2.5cm and then under the action of the catalyst, doubles to a final height of 5cm.
Immediately after being injected, the foam is still in a semi-fluid state and so to make sure that it doesn’t leak out I seal the injection hole with a piece of simple masking tape. The frame is then put on a special vibrating bed for 5 minutes to ensure that: 1) the foam adheres uniformly to the tube walls and, 2) the possibility of the formation of minor air bubbles – that could compromise the foam’s performance – is eliminated.”
a little more on their use.
STRUCTURAL FOAM INJECTION
Once again existing EV2 technology is applied to maximise the advantages of the EV4 frame. Structural Foam Injection, originally developed for thin-wall tubing applications, is fully compatible with the EV4 design philosophy. The bi-composite, non-toxic foam, developed by Henkel and then patented by Bianchi for specific bicycle tubing reinforcement applications, produces an increase in rigidity of 15% at the bottom bracket area and an increase in the frame’s resistance to fatigue of 100%.
The bi-composite foam also has the function of absorbing load forces rather than dispersing them. Because of this important characteristic, accumulated fatigue in the welded area around the bottom bracket is significantly reduced. The structural foam weighs less than 20 grams.
http://www.bianchiusa.com/site/general/reparto/
Injecting the foam
by Stefano Fedeli
“My job at Bianchi is to inject our revolutionary Structural Foam into the frames. This is a fairly easy job, not least because the foam is not toxic in any way. The process of injection occurs after the painting, clearcoat, decal application and final check of the frame. This is because if the painting of the frame failed quality control and we had to strip it and re-paint it, the paint stripping acid would react with the foam, effectively neutralising it.
I use a large syringe, powered by compressed air, with a 90º curved pipe at the end which can be easily inserted into the opening between the bottom bracket and the seat tube. With this instrument, a controlled dosage of 50ml is injected into the bottom of the seat tube. The foam immediately expands to a height of 2.5cm and then under the action of the catalyst, doubles to a final height of 5cm.
Immediately after being injected, the foam is still in a semi-fluid state and so to make sure that it doesn’t leak out I seal the injection hole with a piece of simple masking tape. The frame is then put on a special vibrating bed for 5 minutes to ensure that: 1) the foam adheres uniformly to the tube walls and, 2) the possibility of the formation of minor air bubbles – that could compromise the foam’s performance – is eliminated.”
a little more on their use.
STRUCTURAL FOAM INJECTION
Once again existing EV2 technology is applied to maximise the advantages of the EV4 frame. Structural Foam Injection, originally developed for thin-wall tubing applications, is fully compatible with the EV4 design philosophy. The bi-composite, non-toxic foam, developed by Henkel and then patented by Bianchi for specific bicycle tubing reinforcement applications, produces an increase in rigidity of 15% at the bottom bracket area and an increase in the frame’s resistance to fatigue of 100%.
The bi-composite foam also has the function of absorbing load forces rather than dispersing them. Because of this important characteristic, accumulated fatigue in the welded area around the bottom bracket is significantly reduced. The structural foam weighs less than 20 grams.
http://www.bianchiusa.com/site/general/reparto/
Honda-Tech Member
Joined: Aug 2000
Posts: 684
Likes: 0
From: Philly, Pa, USA
Re: Do you remember that structual foam? S.C.C. mag June 2000. Did anyone ever try it? (Knestis)
I agree with Kirk, the bond with the metal is the key thing.. I wonder what sort of procedures would be needed to clean out the gunk that's probably accumulated in a daily driven vehicle's frame (if it's open to squirt the foam into, it's open to get grime into..). I would imagine that gunk would severely impair adhesion.
That Bianchi info was also interesting (I remember Bianchi being a premium bike back when I was racing bicycles).. especially regarding the shaker table part of the procedure.
I imagine the applications in which the foam provides the most improvement are also the applications that are somewhat designed with the use of foam in mind. I doubt simply buying the foam and squirting it into any old chassis would yield the empirical results people might expect.. (then again, the placebo effect is very powerful).
If SCC is going to do frame stiffening articles, someone needs to show them how to use a strain gage.. but I guess real data may scare their target audience, and wouldn't be as impressive seeming as glowing testimonials.
That Bianchi info was also interesting (I remember Bianchi being a premium bike back when I was racing bicycles).. especially regarding the shaker table part of the procedure.
I imagine the applications in which the foam provides the most improvement are also the applications that are somewhat designed with the use of foam in mind. I doubt simply buying the foam and squirting it into any old chassis would yield the empirical results people might expect.. (then again, the placebo effect is very powerful).
If SCC is going to do frame stiffening articles, someone needs to show them how to use a strain gage.. but I guess real data may scare their target audience, and wouldn't be as impressive seeming as glowing testimonials.
Honda-Tech Member
Joined: Dec 2001
Posts: 4,035
Likes: 0
From: Greensboro, NC, USA
Re: Do you remember that structual foam? S.C.C. mag June 2000. Did anyone ever try it? (MechE00)
The thought of strain-gauging a strut bar came to mind the other day, dealing with that wackiness...
K
K
Member
Joined: Jul 2002
Posts: 1,006
Likes: 0
From: Renton, WA
Re: Do you remember that structual foam? S.C.C. mag June 2000. Did anyone ever try it? (Knestis)
It's not allowed under any race sanctioning body that I know of (I would hate to think about the toxic smeg that it would produce in a fire)
Honda-Tech Member
Joined: May 2002
Posts: 1,877
Likes: 0
From: Oakland, CA, USA
Re: Do you remember that structual foam? S.C.C. mag June 2000. Did anyone ever try it? (ghettoRacer)
exactly that. un-informed and clueless opinion. very rude follow up post too.
Honda-Tech Member
Joined: Dec 2001
Posts: 4,035
Likes: 0
From: Greensboro, NC, USA
Re: Do you remember that structual foam? S.C.C. mag June 2000. Did anyone ever try it? (rotten)
I remember at the Wild West Rally last month talking to some people that were using it... So I'm pretty sure its legal (in some classes at least) in SCCA Rally... Something like that would have to be specifically disallowed, so I'm not sure where youa re getting 'its not allowed under any race sanctioning body'.
K
Edit = grammar dork
[Modified by Knestis, 9:23 PM 10/5/2002]
