foaming your frame?

[concretejungle]

This really sounds like a stupid question....really.....

watching TV the other day i saw that old commercial of a ford f150 where they say that they apply heat to the frame and a product they put inside the frame heats up and then expands into foam. This foam keeps the frame from rattling and squeaking....

well, that got me thinking. I wonder if i took a few cans of spray foam and sprayed it into the holes of the frame essentially filling them up? Seems like it would keep moisture out, so no rust issues. Also, it would aid in vibration dampening. I wonder how crazy messy or heavy it would be to do the same to door panels instead of applying layers of dynamat?

just thinking out-loud here.....perhaps i'm thinking too much

 

[C6H12O6]

The pourable two part stuff they use for boat hulls would probably be better, but all that stuff is very messy. You might also have the problem of any moisture that does happen to get in there won't be able to get out. Not good.

The doors need room in there for the windows to operate, so you might not want to fill them.

 

[concretejungle]

The doors need room in there for the windows to operate, so you might not want to fill them.

Yea, didn't even think about that. Like i said, pretty stupid question.....can you tell i'm bored at work today.

 

[kennyv0826]

I wouldnt use the foam in a can. The problem you will most likely have is that it may not fully cure in the areas where it is super thick. Unless you just did a little at a time and that would be kind of a pain. Prolly take several days or more to get it done. Then you also want to be very careful that there isnt already moisture or any kind of contaminant that may still harm your frame with the foam there.

I foamed a car of mine to make the chassis stiffer for racing but you need to use a "structural" foam this stuff is nuts! Super strong/stiff & light and pretty expensive and messy to work with (what ever it gets on, it stays on). It may even strenghten the frame (if that's possible on a fully boxed 80 frame?). But I dont know if the cost is worth it or not.

Another option I saw at a home improvent store was a two part foam that works like epoxy (and the more expensive structural foam) so it dosent need the air to make it dry and you could fill bigger cavities that way. I dont remember if it was a closed cell foam though. And if it's not, dont use it because it could actually hold water in your frame instead of keep it out.

Look online for the link to some structural foams and call the manufactures and tell them what you want to do. See what they think, and let us know!

 

[fzj80kidpen]

The frame is boxed but its like swiss cheese.
Holes everywhere all up and down the frame rails.
The frame is painted so it will not rust unless you scratch it up and that will only be on the exterior. Just roll on some of that extra Durabak.
The inside you need not worry about and the holes let water drain and keep it nice and dry.
Putting foam in there would work but it would end up collecting mud, sand, then get porous and end up collecting water and accelerate rusting. Even expensive closed cell foam in kayaks eventually gets water logged.

 

[CreeperSleeper]

Interesting... I just trimmed my rear fenders out and I'm trying to think of a way to re-seal the inner fender with the quarter panal. I can weld some spots together (as it is close enough), but the body on my 80 is so beat that I have an inch gap in some spots... I wonder if something that this would work.

 

[concretejungle]

my basic idea was any "empty" cavity where there is a chance of water collection or parts just rattling free, you could fill it with foam. Especially if you know there is no need to get back in that area for any reason. For the frame, the foam that comes out of the holes, just cut/sand flush.

Kidpen, funny you say that. My first job was building kayaks for wilderness systems. We would fill the front and back of the boats with foam.

What about the docks that float on foam blocks? THose don't water log.

 

[83bj60]

my basic idea was any "empty" cavity where there is a chance of water collection or parts just rattling free, you could fill it with foam. Especially if you know there is no need to get back in that area for any reason. For the frame, the foam that comes out of the holes, just cut/sand flush.

Kidpen, funny you say that. My first job was building kayaks for wilderness systems. We would fill the front and back of the boats with foam.

What about the docks that float on foam blocks? THose don't water log.

Indeed. The urethane foam used in construction and many other projects is waterproof, and so is the polystyrene foam used for docks. Polyurethane foam requires moisture to cure so that should be good, however does it scrub the substrate of moisture while curing and is it impervious to water vapor once cured? In any case, I'm leaning towards foam in frame=good (after all, por-15 is poyurethane based as well)

Time to make some experiments with some box tubing...

 

[BROKEROB1]

Heck, you may achieve buoyancy....

 

[Rookie2]

As a side note, anybody else think that commercial where Toby Keith starts pulling frames out of his backpack and says "this bad boy is fully boxed" as the two guys sitting in the booth start to quiver, was about the jokiest commecial ever?

Now if he said "this bad boy is fully boxed and has foam in it", that'd be different .

Continue on...


Rookie2

 

[vlinker]

This really sounds like a stupid question....really.....

watching TV the other day i saw that old commercial of a ford f150 where they say that they apply heat to the frame and a product they put inside the frame heats up and then expands into foam. This foam keeps the frame from rattling and squeaking....

well, that got me thinking. I wonder if i took a few cans of spray foam and sprayed it into the holes of the frame essentially filling them up? Seems like it would keep moisture out, so no rust issues. Also, it would aid in vibration dampening. I wonder how crazy messy or heavy it would be to do the same to door panels instead of applying layers of dynamat?

just thinking out-loud here.....perhaps i'm thinking too much

I think you'd end up with accelerated corrosion in your frame and a bunch of messy foam to deal with.

 

[baxter650]

I could be wrong but i don't believe they put it in the frame, they put it in the A & B pillars of the cab for sound deadening.

 

[IdahoDoug]

I don't think they're (Ford, or any mfr) using foam for structural reasons. Just as Baxter surmises, the upper greenhouse pillars on some vehicles are foam filled for quietness. We did this 17 years ago on the first generation Lexus LS400 and now others are following suit. The A, B, C pillars, header bow, and some parts of the rocker panels have a noise deadening foam in them to stop the transmission of noise from the road to the passenger compartment.

As for using foam to strengthen the frame. Some foams are capable of it, but there's no weakness in the 80's fully boxed frame to fix. Not a good anti-corrosion strategy. Incredibly messy to do for near zero benefit and high % chance of a negative (rust, inability to access in future, etc). As for rattles - if a mfr puts its car frames together so poorly that these heavy structures actually rattle then you've got bigger fish to fry that foam will not cure.

DougM

 

[firetruck41]

I think that foam in the frame will not prevent water from collecting or rust from forming and may actually be detrimental. The foam may be waterproof, but there is no way you are going to get the foam to adhere to the frame and provide a 100% water tight bond from the foam to the metal of the frame. Water and dirt/etc. will seep in, and have a very difficult time drying out.

 

[DTAYLOR]

Also consider ...

If they do actually do this, it is clean new metal, not old dirty metal. How would one clean those inside surfaces for the foam to stick to?

 

[Big Red 64]

The PO of the 76 FJ40 I bought last summer actually tried something like this. I think he was trying to keep the snowflakes from working their way in (common in the hardtop cruisers I've had) and sprayed foam under the front overhang. It has rusted worse than anywhere else on the truck. The foam per se doesn't get wet but it has really kept the moisture in and created a major rust problem. I certainly wouldn't advise using it.

 

[D'Animal]

Fix the thing that is squeking and rattling.

 

[co279]

I have heard stories about a guy who sprayed a can of foam in the framework of his hood and it actually expanded the sheet metal outward. I dont think I would take a chance. Raised dents are not a good thing.

 

[scottryana]

Funny topic, I actually saw my first foamed frame just 2 weeks ago. It was the frame of an FJ40 down at Ironpigoffroad. The customer didn't know who did it, but it had survived several years like it was. I still think that it is a very bad idea. What if you ever waned to weld on the frame? Melting foam would be a bad thing

Ryan.

 

[lowtideride]

Horrible thing to do to a frame, if itsnt rusted now it will be after your done foaming it. You could seach this in 60s tech because Its been talked about a bunch of times.

I have been looking for plugs for the larger holes in the 80 series frame on the outside. there are factory ones in some spots but I still need to block off the rest and leave the small holes for evaporation. I think the best thing to do is make sure large amounts of mud or sand dont find there way in.