[ScotY]

Is it okay to use panel adhesive to glue epoxy-primed patch panels? The adhesive instructions say to "remove any adhesive, e-coating, corrosion protection or galvanized coating." The problem is I have pitted, rough textured metal (it was spot-blasted then painted) that I need to glue to and there's no real easy way to get the paint out of the pits, aside from sandblasting it again. Wish I had thought of this earlier.

[Runnin'OnEmpty]

No problem, just sand the epoxy off as much as possible. If there's some left in the pits, there'll be little effect if any on the bonding.
The rough surface will actually strengthen the bond.

[deadbodyman]

just wire wheel the pittsI got a 48 i'm gluing up in my journal

[MARTINSR]

I am torn on this one. Listen, there are circomstances where the manufacturers recommendations would be to epoxy prime it BEFORE bonding. A C5-6 Corvette inner fenders for example. How about urethaning a window in, epoxy first.

But man-o-man I am torn on this one. I think I would sand blast it again and bond it. Just spot blast the edge where the adhesive will go. We KNOW that works, so you can't go wrong.

Mike, I personally don't like using a wire wheel it always seems to "shine" the metal more than clean it. And if it does clean out the pits, it leaves the metal so shiny. I prefer to go with a Red ROLOC "Surface conditioning disc" which scratches it a lot better. And STILL after that I just MUST run over it with a nice new 50 grit (or even 36) disc before bonding (just as the instructions on the adhesive I use says).

But to spot sandblast it, ahhhhh, that I feel real good about before bonding.

Then apply the adhesive and be sure to spread it out with an acid brush covering all bare metal that will be hidden and to press it into the scratches. THEN apply a little bead over the top of that on one panel and press the two parts together.

Brian

[deadbodyman]

I use a real course wire wheel or cup,but I agree to spot blast is best just not at my shop,there my be a race motor being built in the next bay.not only that as my nick name the "deadbodyman" suggests,I build a great many lost causes, " dead cars" and they do last so i dont want to take any more than the rust out,I can control that much better with a wheel.I think you know my next step treat and etch and the product I use.that urathane windshield glue also works great for sticking wide body mouldings on,I dont like double stick tape to much. I picked up some cold galvinizing in a spray can to use insted of weld thru primer something someone recomended so far I like it and its 1/3 the price, same stuff inside i'm told ,didnt have my glasses but it welds good