metal adhesives

[rossco]

I'm doing a simple lower rocker panel patch. Who has had any experience with metal to metal adhesives?

 

[BG 62AH]

I have used SEM panel adhesives. They are very strong and work great.

 

[Deleted member 19315]

Don't do it......please.....just carry out a simple traditional welded repair. Or find someone who can.

 

[rossco]

haasad. Care to elaborate on your comment? I'm looking at welder options but before I choose one I'd like to know more about adhesives and results of their use by those who have tried them.

 

[RAC68]

In 2002 or their about, aluminum adhesive used in the repair of BMW aluminum bodied cars was used to repair my rear shroud after it was destroyed from lights down in a collision. New lower panels were acquired from Healey Surgeons and it was thought the adhesive would be much better then welding old aluminum to new. Although I believe the adhesive is still in tact and performing well, a fine crack in the paint has formed across both joints and the owner of a body shop suggested it was the result of the body filler failing across the joint. Although these paint cracks are not at all obvious to anyone other then myself and easily eliminated with a small repaint and it is too small an issue to extend any effort.

Since my use was more then 10 years ago and the cracked paint appeared maybe 5 years later, I am not sure how valid it would be as a reflection of todays adhesives and fillers. However, I would approve the use of adhesives today but more questioning on its application related to how potential joint flex would be handled by the paint and filler to be used.

Ray(64BJ8P1)

 

[HealeyRick]

Take a look at David Townsend's use of the 3M product here: https://forum.britishv8.org/read.php?13,8996 Car's not on the road yet, so don't know how it will stand up to stresses in the body.

 

[Healey 100]

I have used 3M Panel Bonding adhesive on another car and so far I can see it offers a number of advantages compared to welding -- especially when dealing with panels without good access to both sides. Welding inevitably distorts the panels and the collateral damage to has to be straightened. I have seen it used very effectively on difficult bodywork problems, like replacing the flat sides of a VW bus or chopping the top of a street rod.

Welding is probably stronger, but butt welds often have tiny pinhole leaks that can eventually destroy your repair from the inside. If you do the bonding right, there will be about a 3/4 overlap that ends up being filled with epoxy and watertight.

I would follow the instructions carefully. Have not tried it with Aluminum, but that's a good application considering how hard it is to weld aluminum.

 

[vette]

I have used SEMs and 3M panel bonding adhesives with very good results. In all the ones I have used, in their application instructions they all state that for maximum strength structural panels should also be spot welded. i have only used it on applied panels for panel replacement/repair. But to me it has two downsides. One is that set up and drying time usually means once applied you are done with that panel for the day. The other downside is that it is expensive. I haven't bought any in a while but the twin tube product usually cost between $35 and $45 dollars a package. (plus you should be using the twin tube application gun) If your not using it all in one application the balance of it has limited shelf life.

 

[vette]

I have a friend of mine that has a right rear fender dog leg patch on his MGA that he put on 30 years ago with bonding adhesive. It is still in excellent condition. No lines of shrinkage or loosening what so ever. An that obviously was an early formulation.

 

[Deleted member 19315]

Ok . And it's my personal view. I'm sure that technically the range of modern adhesives includes something that will work. However it doesn't sit well on a car built over 40 years ago. Welding is not a skill that's short in supply nor is it one which given some time and good education cannot be learned to standards good enough for car repair both in aluminium and steel.The capacity to hand work after welding is also an advantage.
I'll get my coat........

 

[MisterB]

Just my $.02-- I've used both and have found that each has their place. On a lap application the adhesive can't be beat. No moisture infiltration to start another rust out cycle. Window channels are an especially good place to use a lapped bonded repair. Not used so much on a Healey but other coupes. I could see that floor panels, trunk panels, etc. on a Healey would be an especially good place to use adhesives. lap, bond, done.

 

[Healey Nut]

The superstructure of my 07 Aston Martin is all glued together and they continue to do it this way so it cant all be bad if you do it right .

 

[rossco]

Seems as though one might draw the conclusion that frame, sub frame, engine compartments and other hidden areas are safe for use with adhesives but exposed areas such as sheet metal (fenders, rockers, etc.) and cosmetically detailed areas are better repaired with a welding process. Some have debated those points right here in this post. Glad there are options and it sorta boils down to technique and faith in your own attention to detail. Thanks to all for the good info.