tricky patch panel fabrication and installation

ok. totaly off-topic car (68 Firebird) but i figured the techniques are all the same and in fact this patch panel is a bit more complicated than that of what you might need to build for that model A or even most 50s cars.

i did'nt use ANY fancy equipment what so ever, save for my shrinker/stretcher. no sheet metal brake, no shear, nothin!

check it out...


here is the area that was rusted. it had actually had a realy nasty patch brazed over top a rust hole and covered in a quart of "mud". that just won't do for me, even if i am just sellin the car.



first thing we need is a piece of sheet metal the same thickness as the panel we are going to be patching. cut the piece just a little bit oversized for the area to be patched and don't forget to account for any bends or curves in the patch when figuring the size.



now to brake an edge without a sheet metal brake. first we draw or scribe a line at the point where the bend needs to be. the sharper the line the more accurate the placement of the bend will be. that's why i'm marking it with an ink pen and not a Sharpie.



next you need a metal bench (or something that'll work just the same) and a piece of angle iron. line up the mark you made on the work piece with the edge of the bench. then lay the piece of angle iron over the sheet metal on the line and clamp it down at both ends. (NOTE: you can also achieve the same thing with two pieces of angle iron in a bench vice. just clamp the work piece in between the two pieces of angle iron.)



start hammering the flange over the edge of the bench A LITTLE AT A TIME with a body hammer. don't try to hammer it all the way to 90* in one p*** or you will distort the edge.



hammer it over a little more...



until you have the angle you want (in this case 90*).



next i needed to put a little curve in the piece so i put the flange through the shrinker until i had the right curve.



i also needed to put a slight roll in the one end of the piece to follow the shape of the fender. i did this by putting the jaws of my vise very close together and GENTLY bending the piece a little at a time, moving the piece up and down in the jaws of the vice as i did my little bends until i had the curve i needed.




then it was time for another test fit. (NOTE: you should be test fitting quite often as you go about making your patch panel to ensure proper fit.)




then i needed to add this real tight little curve on the under side of the fender, to match what was there from the factory. after a few minutes of head scratching i grabbed a piece of solid round stock out of the s**** bin. i placed the stock where i decided it needed to be on the inside of the patch and then i tack welded it into place. be sure to tack weld on the OPPOSITE side of where you will be hammering (unlike the one i had to cut out after welding it by accident on the wrong side).

 

next i laid the piece on the bench and used the flat blade end of my body hammer to carefully work the metal along the edge of the round stock and cause a depressed edge just where i needed it. do this untill you get the depth you want. careful hammer blows will keep the piece looking as smooth as possible.




you can see here how far we have come so to this point. you may also notice a couple of cuts i made earlier in the flange to get it to do what i needed it to do. your needs may vary but hopefully by watching what i did it will make your next patch go a little easier.




i kinda skipped right over the welding portion (did'nt even take any pics). that could be a whole other "how to" all it's own and could depend on what process you use.
a couple notes on welding sheet metal. first. TAKE YOUR TIME! second. TAKE YOUR TIME!...
there are basicly 3 different processes that you would be likely to use in this situation. TIG, Oxy/Acetylene and MIG. TIG is probably the best followed by gas welding, but since most of us have MIG welders and that is the process i am most comfortable and most practiced with that is the process i have used here. it can be quite effective as long as you realize it's limitations and work within those. i go one tack weld at a time at the lowest heat setting that will still offer complete penetration. skip around the patch leaving tacks and don't let the area get very hot. i like to get part way through laying tack welds and then knock the heads off the welds with a small sanding disc on a 90* air sander. same deal with grinding, TAKE YOUR TIME!. you can get the panel just as hot and just as warped by grinding as you can by welding.
in order to get a near perfect patch that will need little or no filler you will also need to put down the welder now and then and do a little hammer and dolly work to make sure the seams are still lining up and that the metal is staying where it is supposed to be.


here is the patch after welding, grinding and final sanding of the seams. (NOTE: the smaller the gap on the seam between the patch and the original part, ie, the better the fit of your patch, the easier it will be to weld and the better the result you are likely to end up with.



here you can see the part after final t******* along with where i did a little bit of careful hammer and dolly work basicly "working" the sheet metal skin into the depression in the heavy brace below it, just as the factory piece was.



and thats that. there is likely still a small amount of light hammer and dolly work to be done but this fender is'nt perfectly straight anyways and it isn't necessary that it be metal finished or perfectly dent free. some heavy fill primer and/or maybe a thin swipe of high quality body filler is perfectly acceptable to me in this situation.

 

nice tech. thanks

 

Nice looking work!

John www.ghiaspecialties.com

 

damn dude.wish you were my neighbor...............dave

 

you make it look too easy

 

thanks guys. it's realy not all that complicated, as long as you take your time and think through what you are doing.

 

nice work mike...even if its a mullet mobile

 

Hey ,the Mullets belong with the 3rd gen Firebirds not the first gens. I have 3 First gens and I have no Mullet and never have and never will. I wont even let someone with a mullet in my car!!!! Hell with the way Im losing my hair, I'll be bald before experiencing gray!! LOL!

 

Thanks for the helpful info! I have been fabbing patch panels in a very similar way (No metal brake, etc.). But I always do the welding too soon and impatiently. Your tips on the test fitting and welding sequence (checking fit and truing it w/ hammer & dolly in between welds) is exactly the info I needed today!!

Oh yes, and as an official over-the-top narrow minded car critic, the first generation Firebird are NOT mullet cars. They are the best looking pony car of the day, especially better in front and rear lights/ trim than the first three years of Camaro's! Plus they are Pontiac! Pontiac ruled the factory style department from '60 to '70 hands down. Yikes! I'm talking too much...

 

Oh yes, and as an official over-the-top narrow minded car critic, the first generation Firebird are NOT mullet cars. They are the best looking pony car of the day,

i bet to differ....i think my 70 amx is better lookin then a firebird! although, i do actually like birds, I'm bond by my traditional oath to call mike out!

 

Girl car.

Nice work tho!

 

+1.

 

Holy tech in the nick of time batman.....I will be doing the fender bottoms on my galaxie with the same types of curves and pain in the *** brace. This is a godsend, thanks a bunch. Excellent job.

 

LMAO! when i first bought the car this past spring and parked it next to the lifted 4x4 i bought last summer i said to my friends that i'd have to grow a mullet now.
i've decided instead of doing a full rottisary restoration like i had intended that i would patch up what few bad spots the car has and sell it. it's realy a GREAT candidate for restoration or rodding but it'd make a cool driver as is as well. it's got a 400 and a 4 speed and runs like a ****d ape. California car too. not rotted in all the usual places these cars tend to rot in this part of the country.

 

had to go use the brake at the local community college today (GMgrunt is a teacher there now and got me in) to bend up a replacement piece for the bottom 6 inches of the brace on the other fender. heavier steel and a couple bends real close to each other made bending it over the edge of the bench kind of a ***** to pull off very well, so i cheated. LOL fact is i'd cheat on everything if i had the equipment to do so... garage should be toasty warm in a few and i'll be back at it. gotta get this thing back together so i can off it and concentrate on other projects. even if it does'nt sell right away at least it'll be "done" and i won't have to think about it. i'm attempting this new theory i've been hearing about. it's call "doing one project at a time". interesting idea. i'll let you know how it works out.

 

repaired the brace inside the other fender today. it went a little somethin like this...


first i cut a piece extra long and a little wide. measure and bend in the appropriate places to match the shape of the original brace (or what was left of it).




i measured how much of it would be the upper section and put a slight curve in it by putting the flange through the shrinker. did'nt need much.




measure where the bend needs to be and cut a notch then clamp it in the vice and apply some muscle. took a little bit because of that dog leg bend but it was short enough i figured it was worth givin it a go without heat or cutting.





a little tweaking with the hammer over a solid surface cleans things up nicely.





oh yeah. this is what the area looked like before i started work. the rest of the brace was still there but with a large hole rusted through it it was no longer attached to anything except what was left of the outside skin at the very bottom of the fender.




and there we have it thus far...




after a little t*******...




needed a little shape in this area so i clamped the part to the edge of my bench and did some careful hammering over the edge of the bench.



then i turned it over and did some more tweaking...





for some reason i tried my best to make this thing look absolutely like the factory piece. not that ANYONE would ever notice. i think there is something wrong with me... anyways. i traced where the hole that was in the factory brace was supposed to be and made some notches with my cut off wheel rough cutting the hole.




then it was time to start welding it on. my bends where not in EXACTLY the right spot (but close) so i had to do a little bending (with vise grips) and some hammer and dolly work to get it all to line up right. a burr on the die grinder cleaned the hole up just like the factory did it....er, uh. sorta.



and VIOLA!...

 

i never posted a real good 'before' pic of the left fender so here is one of each so you know what i had to start with. i had no idea exactly how i was going to fab these pieces when i started. i kinda thought it through as much as i could and then decided on a logical starting point and went from there. you have to stop now and then as your making the part and THINK about what you are doing and what it makes the most sense to do next. just like with anything else, the more you do it the better you will be and the less often you will have to stop and think about it. don't get too ****y though, thats when i find i make the most mistakes. believe me, it realy ****s to get 3/4 of the way through with a patch like this only to realize that you cut something too short or put a bend in the wrong place and now you have to start over... sometimes that is unavoidable but it still ****s so just take your time and think it through. would'nt hurt to make the part out of poster board first whenever possible either. that'll let you figure some things out before going through all the work of making the part in metal. it's ALOT easier to make it from poster board first.

 

Hey Kustombuilder,

Great job on the fab work and photo posting!

In 1977 I redid a '58 Coupe de ville in white lacquer, for a friend.
Same deal as you FBird, rotted skirt areas on both of the front fenders, inner reinforcements, as well. Even back than I couldn't find "clean" fenders for this car. I wound up rebuilding about a 1/3 of the skirt area on both fenders, including the inner reinforcements. I cut out all of the rotten metal I could see, and the aluminum tape & 1" of filler or the old repair. I sandblasted all of the inner and most of the outer areas of the repair. I did
however leave some pitted metal right where I welded in the new inner reinforcement, figgering it looked sound enough. I finished the repair, refinished the car in white lacquer, and returned it to the owner. Six months later, I get a call, "hey, my fenders are raining rusty water" I popped the stirt bolts to see what's up and the metal above my repair, the pitted area I though was o.k. had begun to rust badly. Moral of the story: always cut out ALL bad metal in or around repair area!

Again, great job on this fab & post!

S****ey Devils C.C.
"Meanwhile, back aboard The Tainted PorK''

 

It's official. You are sick. NICE WORK!

 

Very nice work man!

 

i agree. i've tried "skimping" in the past and not quite gettign all the pitted area out and always regetted it. usualy right away as it would blow through when i tried welding in the patch... glad you brought that up.

 

i'll sell it to ya!!

 

back to the top for TECH MONTH

 

Great tech, excellent pictures. I am learning to do **** welds on my mig welder at this time trying to get things just right. Will have to do some patch panelling this spring and want to be ready for this new project of mine. All the advice so far is very helpful from fellow forum members.

 

That was very nice of you taking the time with the pictures, and posting the information about the patch panels. When I can get to it I have pretty much the bottom on both sides to rebuild plus the floor. Rockers are nonexistent and a little bit holding above the rear fender. One of those e-bay cars with hide um picture, and not a truth full description of the car. I guess most have been there and had a similar fate. I'm in to deep to s**** it.

 

nice work!

 

Very nice! I have 3 first gen Birds and 1 first gen Camaro and I know what you mean about them rusting. My bird 400 convertible has had indoor storage since the early 80's(hasn't seen any daylight since 87') so that one is still solid & rust free but the 400 coupe needs the IDENTICAL repair to both fenders. The other coupe is real rough but I refuse to get rid of it just because it will make a great donor car someday. The Camaro has solid sheetmetal but the damn package shelf is starting to rust out!

 

great job nice work! as always!!!!!

 

Great job! Too cool, gotta love low tech..