Gluing patch panels in..........

[protouring70]

I was at school tonight and as I was leaving I dropped by the paint and body class. The instructor was having the students put the patch panels in with epoxy! He said that this is the new way of doing them instead of welding. I didn't say anything but it looked like crap.
Has any one heard of this?

[kochevy67]

Yes a lot of shops are doing this on newer cars. I heard it holds but I owuld never personally trust it.

[absintheisfun]

Scary as it sounds, this is actualy the way many modern cars are built at the assembly plant!

Even scarier? 3M has a 2-sided tape so strong that when it is used to join two pieces of metal, its tear apart strength is greater than the same two pieces of metal when welded together!

[v7guy]

my only concerns would be regarding filling the gaps and having them last long term.
I've seen epoxies so strong that when dropped on concrete and you try to remove it the concrete comes up with the epoxy.

[NOT A TA]

I've used the 3M two part panel adhesive. AMAZING strength! First time I used it I bonded a bunch of small sheetmetal scraps together and tried to separate them with mechanical force, chisels etc.. Can't be done without tearing the metal. I've found it comes in handy for certain situations such as repairing window channels where you'd normally need to remove interior parts to reduce the risk of fire welding.

I replaced about 8-10" of exterior sheetmetal of this C pillar in my 74 Camaro. It had rusted through where the vinyl top ends from the door window to the rear window. Used a panel flanger, formed a piece of sheetmetal, and bonded it in. Skim coat, primer and paint as usual. Sold the car a few years later with no signs of the panel repair in the paint even though it was stored outside in New England (yes new owner was informed). This was a bracket race car and I expected ghosting on an upper panel that the sun would beat on. I wouldn't do that type of repair on a show car upper panel because the thick area where the patch and original sheetmetal overlap will heat and cool at a different rate and I still think ghosting would eventually occur on any panels subjected to direct sun. A low panel down by the rockers or bottoms of the fenders would probably not have a ghosting problem unless the car was rountinely subjected to extremes like going from a heated garage to below freezing temperatures.

https://static1.pt-content.com/images/pt/2010/11/MVC014F-1.jpg

[DartorDemon]

I was at school tonight and as I was leaving I dropped by the paint and body class. The instructor was having the students put the patch panels in with epoxy! He said that this is the new way of doing them instead of welding. I didn't say anything but it looked like crap.
Has any one heard of this?

A mopar mag used it with a manual tranny swap(new cover) and had good luck with it.

[Josue]

I've worked with 3M's Panel Bonder for years, definately as strong as advertised! Much easier than breaking out the welder too, and filling in a bunch of plug welds. I'm actually on my way to work right now to glue a quarter panel on a 07 Saturn Aura right now....lol (some welding is still required though) You can glue quarter's, roof's, and door skins on with the stuff. Basically, anything with an outer skin. Anything that has to do with the structure of the body, and we have to weld it for strength. Patch panels aren't structural, but see explination below...

However, we're not allowed to glue "cosmetic" seams with the stuff, because it will eventually shrink up and leave "ghost lines" where the seam is. I just took an I-CAR (like ASE for body shops) class on panel bonding, and they don't recommend doing this either. I wouldn't take any chances....just weld it in so you know for 100% sure you won't have any problems down the road.

[protouring70]

Well, its more popular than I thought!

[redss86]

We use two part panel adhesives every day to glue new complete panels on (roofs, bed sides, door skins). Don't use it for "patch" panels. It doesn't expand and contract the same as metal, therefore if you put filler over it it will eventually crack. Hell we even glue all the pinch weld on a quarter replacement, but we still weld and fill the seam.

This is just my .02.

[Black67SS]

This is not new by any means and is accepted widely in the automotive industry.I personally used Fusor brand metal bonding adhesive back in 96' to put a qtr. panel on a dodge shadow.It belonged to a neighbour of mine and I watched that car rot out for the next 4-5 years and it never showed any signs of separating or cracking.Hendick Motorsports tested this product on several of their cars that eventually ended up in wrecks and showed no problems.

[elitecustombody]

As strong as this stuff is,the only patches I would do with metal panel adhesive is a floor patch, this stuff is made for full panel replacement,

it has been around for long time

[topstring]

I just replaced the rear cab corner for a 99 silverado left side,no door so it was huge..i used Fusor metal bond and called them about ghosting lines showing..the truck is pewter..the rep said its not the glue that shows the line,it's the metal.He said grind the edge and bevel it thin then glue and it should hide.I did and I never saw the first ghosting at all.I love it when i can use it,because its obvious welding exposes metal on the back side which is hard to get to to treat sometimes.

[aronhk_md]

Can you use this stuff for attaching fiberglass to metal, and fiberglass to fiberglass? Or is there something better for that? I have a 'glass hood, fenders, nose, etc that I want to assemble into a 1 piece tilt front end. Since the pieces are race weight and extremely light I will need to reinforce it, and I was going to pick up a load of those fiberglass hollow poles the military uses for radio antenna masts....then cut them up and use them as a support structure on the underside.

In the front, I want to have a metal spoiler and front valance, as I dont think fiberglass is ideal for the kind of back and down forces I believe will be developed at high speed. So I envision a sort of "cowcatcher" design like the old trains had....lol. The tilt hardware will be attached to this.

Anyway, I guess I could bond it all with fiberglass, but it seems to me that there must be adhesives today better for this purpose.

Thanks for the help.

[topstring]

Can you use this stuff for attaching fiberglass to metal, and fiberglass to fiberglass? Or is there something better for that? I have a 'glass hood, fenders, nose, etc that I want to assemble into a 1 piece tilt front end. Since the pieces are race weight and extremely light I will need to reinforce it, and I was going to pick up a load of those fiberglass hollow poles the military uses for radio antenna masts....then cut them up and use them as a support structure on the underside.

In the front, I want to have a metal spoiler and front valance, as I dont think fiberglass is ideal for the kind of back and down forces I believe will be developed at high speed. So I envision a sort of "cowcatcher" design like the old trains had....lol. The tilt hardware will be attached to this.

Anyway, I guess I could bond it all with fiberglass, but it seems to me that there must be adhesives today better for this purpose.

Thanks for the help.

I have used Fusor for fiberlass repairs but the part number doesn't come to mind at the moment.Search Lord.com for Fusor product info.

[Damn True]

IIRC Rupp panel epoxied the smooth firewall on the "Track Rat" project.

[aronhk_md]

Fusor.....thanks, I'll check into it.

[redfire69]

Fusor.....thanks, I'll check into it.


Check out this site, they have fusor including metal to FG: http://www.autobodytoolmart.com/lord-fusor-plastic-to-metal-cross-bonding-adhesive-medium-116-p-15938.aspx

[aronhk_md]

Not cheap is it? Ouch. Guess I'll get it all laid out and try to figure out the quantity I'll need.

[elitecustombody]

considering that there is no welding gas,wire,grinding discs,weld-through primer and time doing all the grinding,$28-35 per cartridge is a good price IMO, at least that's what I'm paying and honestly I'd recommend using SEM over Fusor,I've used Fusor and do not like it, the glass beads don't need to me there,Duramix/Automix works without them,SEM don't have them,Norton don't have them.

[aronhk_md]

I was referring to the bonding of fiberglass to fiberglass.....and metal to fiberglass. And comparing an adhesive to using glass resins. I know it wasnt the original intent of this thread.

[elitecustombody]

Gotcha, look into Marine-tex for bonding fiberglass and metal, this stuff is amazing especially in high stress areas, but also not cheap

[aronhk_md]

My experience with Marine-tex is that while it is as strong as steel, it doesnt always bond to flat fiberglass surfaces with the strength that fiberglass resin would. I recall having it shear away a few times. But if it has a surface to "wrap around" even with just minor projections on it then it holds like hell. Have you ever experienced that? My memory is from boats years ago.

[elitecustombody]

Well, I've used it on cars for flares,scoops,grafting ABS plastic,fiberglass,metal and never had it fail

[aronhk_md]

good to know....maybe its something we did or didnt do back then

[liquidh8]

Just be careful that the shelf life isn't expired when you pick the stuff up from the supplier, not good results! Ask me how I know. On my own cars I will stick to MIG/TIG weld my repairs.

[Jon Clough]

you have to be careful to clean up any glue as body filler will not adhere to it

[jake8092]

I'm still a stickler on welding panels in aswell but I agree this stuff is tough! We put new quarters on a 70 impala a few years ago that were glued on, about 2 weeks after it was painted (before we could fininsh sand/buff) my buddy got T-boned making a left turn. The guy was in an SUV ran a red light at about 60 and smashed everything up pretty well.

Long story short...the metal tore right above the glue seem, didnt even phase the adhesive but ripped the sheet metal up like an aluminum pop can

btw Sammys only injuries were a bump on his head where he broke the dash (he's hardheaded as hell) and a few bumps and bruises...gotta love a big american boat!