bob7four
Well-Known Member
I have seen info on a 3m adhesive used in body shops. I have also seen YouTube video of a floor pan install using this adhesive and steel rivets. Any opinions on this method?
Glue and Rivet Floor Pans
- Thread starter bob7four
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My buddy uses the 3m panel bond, tell you what it works well I would have no issues doing it!
69_340_GTS
Well-Known Member
On uni-body cars the floors are part of the structure of the car. I would not assume that the adhesive has the strength of welding.
Mopar-Man
Big Block Better Burnout
3m panel bond is what we use at work and I use it anywhere there is not a torsional force. Those type NEED to be welded. It flows out nicely and is similar to how it sands like JB weld. It is both a seam sealer AND a super adhesive. It can be softened with a torch, so don't use it to put your exhaust together. BUT I will tell you this, my buddy fixed a broken motorcycle shifter shaft that runs into the transmission housing so it is soaked in oil. It was snapped off, he panel bonded it and the guy is still racing it! It WILL glue cast metal! Keep that in mind if you have something like a broken emblem, ect.
GeorgeH
Well-Known Member
No, don't glue the floor pans. I'll never be sold on the glue unless it's used with a weld/bond technique such as what can be done with a Pro-Spot machine. On unibody cars everything is considered structural including the quarters. I've seen enough cars come into the body shop that had panels previously bonded on and were blown apart where they shouldn't have been.
69_340_GTS
Well-Known Member
Sure, it works where it was engineered into the system. Usually it is used to attach plastic or carbon fiber to metal. You will find that where steel-to-steel bonds are needed, even the Corvettes are welded.
As someone who works in engineering design, I can tell you that you never ever want to use an adhesive to hold together a structure/load/torsion bearing part. If you wanted to use it to glue a quarter panel patch on, sure, by all means. To do the floor where the torsion load is, how bout no.
Exactly. Adhesives work great when they are used in specific applications. In those applications the loads applied match what the adhesive is capable of withstanding. That's not just the amount of the load either, it's the direction the load is applied, the frequency of loading, the temperature, etc. If the application matches the adhesive used, you can put airplanes together with some of the adhesives out there.
But if you're not going to run a full on stress/strain modeling analysis on your unibody, I wouldn't suggest using adhesive. You won't really have a good idea if the adhesive that you choose will tolerate the loads it will see, and that could lead to structural failure.
The other thing is, using adhesive is not some magic bullet. It's not super easy. You still have to prep all the parts involved. The clamp forces on the panels during the adhesive curing process are specific to the type of adhesive, and that has to be set up correctly. Using adhesive, especially for structural builds, is not a slather it in glue and slap it together operation. Spot welding is easier in most cases in my honest opinion.
Another possible failure point would be if the car ever got some sub frame connectors......some designs use the floor pan to weld to. So yes they would be connected front and rear, but if using the US Cartool setup, they seem to utilize the pan heavily....could tend to twist that car up proper given enough horsepower/torque.
bob7four
Well-Known Member
Thanks guys. Lots of good information. Sounds like welding is the safest way to go. Looks like i'm buying or buying a might welder and putting a 220 outlet on the garage.
Best decision I ever made was to get a MIG. Make a nice 220 extension cord and be able to weld out in the driveway.
adriver
Blazing Apostle
Well, I won't comment on the floors.
But I just quarter patched one and I used it at the bottom.
Welded the side and then clamped the pinch at the trunk extension.
If I welded it I would have areas I could not treat (easily) and the weld would start to rust down there.
(But my cheap arse HF tig stopped working)
There is a thread on here about the cowl top too.
I did that on a car and I'm very happy with the result.
All the cowl inner metal is protected from moisture.
Could not do that with welding.
The Mfg. told me that it would take some pretty expensive spot welding equipment to weld through it properly.
They were nice enough to stick the old neck out and say they liked it for what I was doing.
I'm really not seeing a big problem in some uses since most of "our cars" were just spot welded anyway.
"Crash durable"
Aftermarket Repair Adhesives | Fusor Automotive | LORD Corp
But I just quarter patched one and I used it at the bottom.
Welded the side and then clamped the pinch at the trunk extension.
If I welded it I would have areas I could not treat (easily) and the weld would start to rust down there.
(But my cheap arse HF tig stopped working)
There is a thread on here about the cowl top too.
I did that on a car and I'm very happy with the result.
All the cowl inner metal is protected from moisture.
Could not do that with welding.
The Mfg. told me that it would take some pretty expensive spot welding equipment to weld through it properly.
They were nice enough to stick the old neck out and say they liked it for what I was doing.
I'm really not seeing a big problem in some uses since most of "our cars" were just spot welded anyway.
"Crash durable"
Aftermarket Repair Adhesives | Fusor Automotive | LORD Corp
adriver
Blazing Apostle
Nevermind.
well It looks like you got lots of good advice and they are right about the 3m glue but there is one more thing you need to know when you over lap two panels together were there is bare metal in the weld area use a weld through primer to keep the rust from forming after it's fixed you can weld on it just like bare steel and it will help lots in the long road trust me I know
famous bob
mopar misfit
I helped the body man / painter that did my fish, repair a late model corvette that was glued to gether "factory" , and believe me, it was a ***** to get apart !
I welded the patch pans in my duster, used a stick welder with tiny rods, PIA but my mig was broke.
The 1/4 panels I used the 3-M adhesive, with spot welds on the pinch points.
The 3-M adhesive is nice to use, but it is not cheap, $40 a tube, and $60 for the applicator gun, plus $2 each for the twizzler nozzles.
If you are just starting on the body work then, money would be better spent on buying a mig, because there will be many more projects that will require welding.
The 1/4 panels I used the 3-M adhesive, with spot welds on the pinch points.
The 3-M adhesive is nice to use, but it is not cheap, $40 a tube, and $60 for the applicator gun, plus $2 each for the twizzler nozzles.
If you are just starting on the body work then, money would be better spent on buying a mig, because there will be many more projects that will require welding.
adriver
Blazing Apostle
The adhesive is what is special.
There is nothing special about the applicator gun.
This one is the "same thing."
Get your adhesive first and try it out before you by an expensive one.
Ask me how I know.
$19.97
HDX 29 oz. Heavy Duty Caulk Gun-HD128C - The Home Depot
There is nothing special about the applicator gun.
This one is the "same thing."
Get your adhesive first and try it out before you by an expensive one.
Ask me how I know.
$19.97
HDX 29 oz. Heavy Duty Caulk Gun-HD128C - The Home Depot
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adriver
Blazing Apostle
The internet is all over the place on the weld through primer type.
Do you have any recommendations of a type or brand?
The adhesive is what is special.
There is nothing special about the applicator gun.
This one is the "same thing."
Get your adhesive first and try it out before you by an expensive one.
Ask me how I know.
$19.97
HDX 29 oz. Heavy Duty Caulk Gun-HD128C - The Home Depot
View attachment 1715121654
That gun will not work on the 3-m cartridges, that is just a standard hardware store caulk gun.
The 3-m one uses duel cartridges.
I have used a lot of the NAPA brand with no issues.
to be honest not really. but out here in the farm land farmers are very hard on there trucks. I don't know how may times I've put on new box sides on pick ups and most always they smash the same side at least twice even after 5 years never find any rust in seams. I weld every thing very seldom use glue
adriver
Blazing Apostle
Well, I guess that would be a good reason to with the Fusor brand?
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