[matts37chev]

Originally Posted by MARTINSR

You have nothing to worry about, unless you plan on taking the body off without a firewall and rolling it on it's side.

Honestly, you are breaking the first rule of rodding, trail fit EVERYTHING! I would never even think about welding that firewall in if I hadn't fit the motor, no friggin way. Listen, you ARE doing it properly and no steps back, you have fit the firewall, it's screwed in, you have taken the proper steps, now put the motor in and take the next step.

Brian

Originally Posted by matts37chev

I want the front susp. done, before I make the engine/trans mounts, and I don't have any of that, yet.


Again, thanks for the suggestions and tips

OK, OK
hard left turn

This is one of the reason I started this thread



I just got too excited, when I was seeing some progress



I will finish fitting the firewall, screw it down really well, put only a couple of welds on it, and stop there!

If it does need mods. , it will be a lot easier on the bench, then welded into the car

I will make a new game plan, and find something else to do, while I wait for the front susp. to show up (I haven't ordered it yet, because I cant make up my mind on what to get)

[JMSTOY]

Dammit Brian, you scolded me into changing my game plan! I know this was not my thread, but thanks all for the advice, I was actually kicking this around too! Keep up the good info!

[MARTINSR]

What plans are you changing?

Brian

[matts37chev]

dang it, now i'm going to have to address this stuff

I was avoiding it, but I knew it would have to be done soon

[JMSTOY]

Originally Posted by MARTINSR

What plans are you changing?

Brian

Finishing my firewall without mocking up my engine. Its too easy really, I'm just kinda getting ahead of myself. Well, I WAS getting ahead of myself till SOMEONE had to go and make sense of some stuff. Its ok, I needed that kick in the pants. Lol

[66GMC]

I hear you loud and clear on the motivational front, Matt.

I've subscribed to this thread in the event that I ever get "a round tuit" and deal with my own 66GMC - 454 dilemma.

Where did you buy the firewall?
Was it Direct Sheetmetal?

They have a few installation instructions / suggestions on their site as well, I think.

It sounds like Brian has made it fairly clear on the welding technique ... thanks for that. You can be sure that there will be a new MIG welder and several practice sessions involved before I tackle it myself.

[matts37chev]

Originally Posted by 66GMC

I hear you loud and clear on the motivational front, Matt.

I've subscribed to this thread in the event that I ever get "a round tuit" and deal with my own 66GMC - 454 dilemma.

Where did you buy the firewall?
Was it Direct Sheetmetal?

They have a few installation instructions / suggestions on their site as well, I think.

It sounds like Brian has made it fairly clear on the welding technique ... thanks for that. You can be sure that there will be a new MIG welder and several practice sessions involved before I tackle it myself.

yes, I got it from direct sheetmetal

they were great to deal with

[123pugsy]

Originally Posted by matts37chev

dang it, now i'm going to have to address this stuff

I was avoiding it, but I knew it would have to be done soon

Ya, it loks like you found other things to do in the meantime.

You have my sympathies.

[deadbodyman]

Something you can do while your waiting is to clean and epoxy all those parts

[matts37chev]

that thought has crossed my mind

however, after I thought about it, its too dang cold
I figured it would be better, to wait for it to warm up some

[tech69]

if you weld it right at the bend and just lap it on you won't have to worry about warpage. That curved area will take the heat just fine and it's nothing crucial that you have to open butt weld it. If you're just an inch away from the curve you get warpage easier. Just screw it in all around and use a long screw driver to hold it tight when tacking it in. Soon as it's tacked in all around you can then go back and do your 1/4" tacks, and I don't keep my finger on the trigger. I just do a 1/4" of RED hot tacks overlapping eachother in succession instead of dragging and getting less penetration. Then when I'm done with that 1/4" hot tack I skip to the otherside for the next. I try to stay at least 12" away from the last 1/4" tack to do the next. You'll have it done in no time and when your welds meet in a corner your welds turn out pretty clean...check out my last pic I added and look at the corners of edges, and these are open butt welds! It's a neat trick and makes work easy. With that window channel patch I just perfected the lower channel area in the initial cut and once that was tacked those other areas where it meets at a edge were THEN shaved down with a grinder flush then tacked down. It's a trick when fabricating to leave it a little long cause it saves time and leaves you with a better fit. Only drawback with doing welds at the line is that your curve might not end up perfect but you won't have warpage and your welds turn out waaay better, and it's easier. I know guys who like to do that trick on quarters where they flange the prexisting quarter, lay the new quarter in, and then shave the rough cut on the body line a little so the new panel is cut right at the bodyline. That's one area where I rather make the cut above or rather below the bodyline and take more time to weld and to preserve the natural curve of the bodyline but some guys love doing them that way. My point is, the firewall is perfect for that as long as there's not too much curve and you don't mind getting the exact curve around the corner. From the pics it doesn't look like there's much curve around the corner and would be a perfect candidate for that.

Ok, but probably a little too much info. Don't get me started!

[MARTINSR]

Henry, with all due respect, this firewall was a perfectly flat piece of sheetmetal that they made it from. A few bends and beads were rolled into it, but it is still basically a perfectly flat piece of metal. It will warp VERY easy. Someone with experience and skills such as yourself may be able to just weld this thing in skipping around a foot away from the last weld without warping it all up. But not knowing the skills (we know little experience) Matt has it is WAY better and safer to weld it in taking a LONG time for welds to cool.

If the average guy welded that firewall in with one weld after another jumping around until it was done it would be a warped mess, we are talking warped all the way down into those beads! Now that would be a heck of a lesson for the next time, but I like to see guys avoid those hard to take lessons and let them learn on little easier ones.

Brian

[MARTINSR]

LOL, I was just thinking back at a few of those hard learned lessons in my life. When I chopped the top on my truck at 16 I welded across the center of the roof with a gas torch. I warped it so bad it required TWO gallons of filler before I even touched it with sand paper.

But I was a young punch, it was a good lesson. The other one that comes to mind was really sad and he should have known better. My neighbor who was a professional welder for years and years proved how just "welding" and auto body welding are two different things. He chopped the top on his 39 Chevy sedan and THEN called me to come fix the mistake, a completely destroyed roof, I mean TOTALLY AND COMPLETELY destroyed roof! That and the hood sides, he welded up the vents on the hood sides and warped it so bad they were thrown away, the roof, that we saved, and he used a LOT of filler. This was all done by a professional welder with a TIG. This guy could lay a bead on the back of a pocket knife blade (I had him do one for me) but when it came to sheet metal, that was a whole different story.

Yeah, taking your time is a lot better time spent than re-doing mistakes.

Brian

[Rod and Custom]

Craftsmen learn from mistakes. Smart Craftsmen learn from the mistakes of others. Most of us are a combination of the two.

It's easy to get excited about making a project look different. It looks like something was done, and that's "progress". I'm doing a '57 Chevy for a married couple. Once I got the patching and rough-in done to the main body, I was ready to turn it all gray with primer-surfacer. Knowing that most wives are very "practical" I joked that every time I sprayed it gray with urethane or polyester primers, she would say it just looked the same. I was defending myself. I timed their inspection visits so they could see primer, then filler, then primer, etc. as the body work was finished. The end result is, they could see the difference between the somewhat lumpy original steel and the very smooth finished primered panels.

It is very important to take each step in proper order. Everything should be trial fitted before going to the next step. The time that seems wasted finishing each step is saved on the next step. In body work, extra time spent straightening the metal saves time working the filler. Time spent perfecting the filler saves time with the primer/surfacer. Time spent on the primer/surfacer is saved in the final blocking before paint. It even works for spraying the topcoats. Time spent getting the final prep right and the spray conditions right saves time in polishing and after work.

I agree with welding 1/4" at a time, then walking away. I think screwing the panel in place and tacking it is your best move for now though. I hope you cross-measured the existing cowl to be sure it's square. The time to correct that is before attaching the new metal.

From the beginning of any project, it's important to establish a level line from front to rear, and a correct centerline. We modify cars and change their stance. That's part of what makes them cool. Without the basic reference lines, it's easy to get lost.

I once helped a friend asemble the front sheetmetal on his '36 Ford coupe. When he replaced the floor, he made the car a unibody by welding the new metal to both the body and frame. With the grille shell mounted, none of the hood panels fit. I had the sad task of proving to him that the body centerline and frame centerline were 1 1/2" off at the front. To allow the grille to stand up straight, he had to trim and add metal to all four hood panels. If it had been an aircraft, it never would have flown straight.

Enough philosophizing. This is just another $0.02 worth. I think I'm up to a dime already.

[tech69]

Originally Posted by MARTINSR

Henry, with all due respect, this firewall was a perfectly flat piece of sheetmetal that they made it from. A few bends and beads were rolled into it, but it is still basically a perfectly flat piece of metal. It will warp VERY easy. Someone with experience and skills such as yourself may be able to just weld this thing in skipping around a foot away from the last weld without warping it all up. But not knowing the skills (we know little experience) Matt has it is WAY better and safer to weld it in taking a LONG time for welds to cool.

If the average guy welded that firewall in with one weld after another jumping around until it was done it would be a warped mess, we are talking warped all the way down into those beads! Now that would be a heck of a lesson for the next time, but I like to see guys avoid those hard to take lessons and let them learn on little easier ones.

Brian

That's true about warpage but that's also why I suggested he lap it over and weld it on the edge. That edge will stop a lot of warpage. This of course after he cuts out the old and at least 1/4"-1/2" from the edge. I totally agree with the air cooling thing. Sometimes when I see guys set up with their air blowers right next to them when they weld I want to take it and hide it from them. Such a terrible idea that surprisingly a lot of guys buy into.