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  #16 (permalink)  
Old 04-05-2018, 06:27 AM
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Thats good stuff, DBM. Not using stock moldings however. First post, fourth paragraph. What he is using should make it even less to sweat. Pretty much just need flanges to overlap enough for a weld.

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Old 04-07-2018, 01:39 PM
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As always guys, thanks for the awesome, informative responses. Very helpful and I understand all you've told me.

IDJ, I will proceed with fit using your acclaimed method. I agree with everyone else here: it sounds like the way to go.

That being said, I didn't read all this stuff before I threw the glass up on the car for a very, very rough test fit. This "test fit" probably means little to nothing because the glass still has old, uneven glue in its edges and isn't really held up in place precisely, so it's sitting higher on the DS than the PS, but I did it anyway. Here's what I'm seeing. I wedged it in place best I could by eye-balling it to what looked right. I also compared the position of the bottom edge to my good 70 firebird and also the junk donor 77 I got the roof frame from.

The gap between the top edge where the glass rounds down to the a-pillars and the skin on the PS is way bigger than on the DS. It's like i have to turn the whole skin CCW (that's if you were above the car looking down) about its center, but I don't think I'll get all that I need. Of course this will also affect the side edges which seem to be pretty close right now. This is cause for concern to me, but I don't see anything HORRIBLE yet. Maybe you guys can.

Also, notice how the window sits lower than the roof skin by 1/8"-3/16". This is how it is from the factory. What do you guys think about welding a piece of flat stock down that's the thickness needed to bring the edge of the glass and the front edge of the skin onto the same plane? I think that'd make the rubber window seal/mold look even sharper. It may even be necessary.

Let me know what you think. I'm gonna start fitting how IDJ has instructed.

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Old 04-07-2018, 02:34 PM
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Hey. Glad you're back on it.

When you pull on the corners of the roof skin, that will flatten out the center. A certain amount of this may be designed into the part. Because if its too curved, you can flatten by pulling on the ends but if they made it too flat it would be useless. So be sure the straps don't interfere with this. And if it ends up needing clamps to hold it all the way for welding, thats OK. I mean the skin doesn't have to just drop on exactly perfect so I may have exaggerated there in the interest of avoiding weld warpage earlier. On first gens thats how it is though.

Your solution is likely to be a combination of my and deadbodyman's tips. When I mentioned briefly about the angles of the bends being off, I was touching on what he explained. The step down from roof face to glass bed is what really has to be fine tuned to the individual car body. Both the skin and the car flange can adapt to meet but the glass is your guide.

Not having A pillar skins on prevents assessment of windshield fit. You need to know how the sides fit, they are arguably more important.

Get all the old adhesive off the glass, make little matching half inch tall blocks to tape on and simulate a uniform adhesive bead. Look at and show us the fit from the inside so the glass and flange curve can be seen.

The reason car glass sits shy of flush is so that when a wild tree limb strikes the pillar, it has much less chance of striking the glass. So I advise keeping that below flush. If you make it totally flush the whole thickness of the molding would stick up farther anyway and that might kinda defeat the effort.

Last but not least, you may need bigger than 1/8" holes for a sturdy pick tool or something when prying to bring corners into place. I say 1/8 because I have a punch that size that works good plus thats the pilot hole size I use for drill screws.
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Old 04-07-2018, 02:51 PM
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Originally Posted by idrivejunk View Post
Hey. Glad you're back on it.

When you pull on the corners of the roof skin, that will flatten out the center. A certain amount of this may be designed into the part. Because if its too curved, you can flatten by pulling on the ends but if they made it too flat it would be useless. So be sure the straps don't interfere with this. And if it ends up needing clamps to hold it all the way for welding, thats OK. I mean the skin doesn't have to just drop on exactly perfect so I may have exaggerated there in the interest of avoiding weld warpage earlier. On first gens thats how it is though.

Your solution is likely to be a combination of my and deadbodyman's tips. When I mentioned briefly about the angles of the bends being off, I was touching on what he explained. The step down from roof face to glass bed is what really has to be fine tuned to the individual car body. Both the skin and the car flange can adapt to meet but the glass is your guide.

Not having A pillar skins on prevents assessment of windshield fit. You need to know how the sides fit, they are arguably more important.

Get all the old adhesive off the glass, make little matching half inch tall blocks to tape on and simulate a uniform adhesive bead. Look at and show us the fit from the inside so the glass and flange curve can be seen.

The reason car glass sits shy of flush is so that when a wild tree limb strikes the pillar, it has much less chance of striking the glass. So I advise keeping that below flush. If you make it totally flush the whole thickness of the molding would stick up farther anyway and that might kinda defeat the effort.

Last but not least, you may need bigger than 1/8" holes for a sturdy pick tool or something when prying to bring corners into place. I say 1/8 because I have a punch that size that works good plus thats the pilot hole size I use for drill screws.
I understand. Good advice.

So, the first batch of pics in the OP we're aligned from the back. That created the big discrepancy between inner roof structure flange and roof skin flange on the front that I was fighting.

I took the ratchet straps off and now aligned it at the front. It looks much better. What's strange (in s good way) is it now seems the back aligns better than when I first put the skin on the car. Could the straps pulling on the skin for a week have moved things some? I sure wouldn't think so, but something looks better. Here's some pics.

I'll see what you guys think, but it looks obvious to me that aligning off the front flange looks better. The back flange is where I will drill holes and use the awl or screw driver in drilled holes to pry the ~85 step-down from roof skin to roof-skin-flange to a straight 90 as prescribed by IDJ and DBM- thus pulling the metal out and getting a better alignment with my quarter panel edge.

As you can see from the pics, the rear edge of the quarter on the DS is about 1/4" back further than the rear edge of the roof panel. It's maybe 1-8"-3/16" further back on the PS, so I'll also have to do some difference splitting I think!



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Old 04-07-2018, 03:37 PM
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O yeah. That looks like you could just about undo a few clamps and correct that with your bare hands. Bend the step first, then clamp the outer skin flange back flat all the way across. Not a biggie. Nice roof skin and as we have said, don't sweat lining the edges up perfect because as you see the trimming is very approximate. Average that out and its probably good. Fit everything else you can though, too. Before welding.
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Old 04-07-2018, 04:13 PM
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Yea I agree. Seems like an ok piece. I tried stretching the DS rear corner back a bit so it lined up with the rear quarter edge using the awl method. I gained a couple mm inboard from the edge. It didn't work as well when I tried closer to the outboard edge. With the compound bending going on in this area I think the metal is more rigid.

I bumped the step-down around with a hammer and punch from inside the car. This kicked out the rear of the roof skin just like I wanted. Now the variation between the rear of the quarter and the rear of the roof skin doesn't seem to exceed 1/8".

So now screw it down with sheet metal screws, space the windows up 1/2" to mimic the window sealer, and fit the windows? Also, this is a bit down the road, but what do I do about the anti-flitter "glue"? I saw some threads where guys used the window sealer and injected it up between the skin and the inner structure after the skin was welded on. I think I'd like to put it on top of the roof inner structure before I put the skin on for the last time before welding.

After I get this skin screwed down and in place I'll mark where the a-pillars stubs end, put on the stock skin with the full a-pillar skins, transfer said mark to stock skin, cut stock a-pillsr skins off, weld a-pillar skinds to roof skin, and get ready for final install.



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Old 04-07-2018, 04:47 PM
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I would choose urethane seam sealer over urethane winshield adhesive unless the cars do tend to flutter the roof. If so, sure. My experience indicates that the softest material you can use is best, and that what you're after is just a pad that isn't stuck. Something to take up slack and prevent flutter while not bonding points on the face of the skin solidly to the structure. Because of the nature of heat travel in the different materials involved, you want it supported but not stuck. Thats just an opinion, your mileage may vary.

As for nailing down the cut to make at the pillar seam, I would not trust transferring marks and would prefer to overlap the skin by a quarter inch or so, over the new pillar skin. Mark that and narrow the overlap to about a Sharpie line width then cut through both layers within that overlap. If I read it right, what you want to do might work, just leave extra and sneak up on final cuts.
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Old 04-07-2018, 05:39 PM
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Originally Posted by idrivejunk View Post

As for nailing down the cut to make at the pillar seam, I would not trust transferring marks and would prefer to overlap the skin by a quarter inch or so, over the new pillar skin. Mark that and narrow the overlap to about a Sharpie line width then cut through both layers within that overlap. If I read it right, what you want to do might work, just leave extra and sneak up on final cuts.
This is precisely what I was planning on. Leave a litle wiggle room.

Of course after my last post I couldn't leave well enough alone. I took the skin off and tried bending the flanges out. The rear one got through this process unscathed. There were 3 time on the front where I had my channel lock or clamping vices oriented wrong though and I dented the top a little bit. I did some hammer off dolly work and minimized the high point. The rest will send off. It's probably about .003" tall. The low spots around it are about a wuaryer size and are about .5-1mm low.

As you know from my last roof skin experience I'm not good enough to take fixing a large, nearly-flat panel. I'm letting it go and the filler will take care of this. Here's the finished product. The end of the steel rule shows where the little high spot is. Looks worse than it is in the shop light. I positioned it so you all could see it.

NOW I'll do the a-pillar skins. That's it this time. I promise!


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  #24 (permalink)  
Old 04-07-2018, 06:00 PM
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You mentioned the height of the glass in a previous post. I'm no body guy, but have a few friends that do custom work....they weld ledge pieces in the window channel to raise the glass and to take the place of the factory butyl glue bead when they do a flush fit glass deal.
It won't look right if you don't.

It's a totally different style of fit than the factory with the clip-on edge trim.

They also add to the edge of the A-pillar skin to narrow the opening, so that there is only an 1/8" or so gap on each side from metal to glass for the urethane glue to fill. Along the top of the glass the windshield is just pushed up to get that gap, most windshields are typically longer than needed at the bottom and this 1/4' or so push up doesn't pose a problem, the bottom is hidden under a hood edge or cowl panel.

NOT the same as using this type of trim though. This is not true flush fit glass if you ask me, this is a cheaper, not a smooth or modern looking easy way out.
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  #25 (permalink)  
Old 04-07-2018, 07:01 PM
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I have not messed with flush glass yet so I don't know whats best for that. Already forgot the conversation we had about it before but I think he linked to a kit with different glass. Not sure. If I did my car I would rather extend panels and have a tiny bump of a molding. If I had to use stock glass. The top curve on the TA windshield might go without mitering. Who knows? I sure don't but any tastefully done flush glass or close to flush is cooler than the stud /clip / trim madness if ya ask me.
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Old 04-08-2018, 11:22 AM
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So I just cut the a-pillar skins off the roof skin that I mangled so badly in the summer and fall of last year. I mocked them up and the DS is pretty far away from the top edge of the door. Like probably 3/4". There must be something different in the full rocker that I placed on that side already. This gap is typically 3/8" - 1/2". PS is about right at 1/2" or so.

It was my plan to pay close attention to this area at the beginning of the project. Go look at these 2nd gens at car shows and you'll see the a-pillar skin is never the same distance from the top edge of the door on any given car between the PS and DS. I've always noticed it, it's always caught my eye, and I've never seen anyone else mention it! I can't believe it. Anyway, I wanna make mine symmetrical.

I was looking at how hard it would be to modify the top of the a-pillar skin where I'm gonna weld it to the roof skin because of the curves and edges. I finally realized that I need to add metal to the middle of the a-pillar skin! That's the right thing (and easier thing) to do, isn't it? Take a look at the pic and see how the a-pillar skin lines up with the drilled spot welds on its underlying structure and thus places itself 3/4" away from the top of the door. Imagine sliding it down and just cutting that much lower to mesh with the roof skin. It won't work. This is where splicing in the middle comes in I think. Tell me if I'm on the right track. I took a picture of the old t-top roof I cut off. I can cut a little 1/4" donor rib out of it to weld into the grey a-pillsr skin.

That all being said, I think I need to hold off on the roof skin right now. I still need to replace the full PS rocker (pictured), and I think I best do that to make sure everything shakes out right for the a-pillar to rocker interface. Again, am I on the right track? Right now the roof structure is welded at the inner quarter structure and DS a-pillar base. The PS inner a-pillar is awaiting the new full rocker.

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Old 04-08-2018, 12:26 PM
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IF lengthening that piece will allow the tailored fit you're after, OK but I might not opt to do it the middle, I'd probably go near the top to keep all the seams in one area.

This is where I'll probably start sounding like a broken record...

Yes, thats a problem spot on all of them and yes rocker and pillar placement are critical and come first.

The amount of space you have is WAY bigger than even what I have gotten used to seeing on these. If I ran into that, I would start back at square one and measure until I had eliminated all other potential causes besides faulty part.

From previous experience, I can tell you that if you are serious about being the guy with the one 2nd gen that has a lovely intersection of roof, fender, hood, door and on both sides...

You will have to have ALL bolt on sheetmetal installed, latched, and adjusted, including core support but excluding trunk lid.

No door hinge wear allowed.

Any rubber bumpers or seals that touch the hood should be in place. Yes, even the shaker seal presses on the hood so this is with engine in if you are serious.

Front subframe should be in, centered in it's small range of adjustment if applicable, and supported or on suspension.

Door and window seals should be installed, along with properly adjusted door glass.

Most importantly, the hood, fender, and door edge moldings plus any drip rail or windshield moldings MUST be installed or at least in place. The hood, fender, and door edge moldings MUST be lined up at this point or you are pissing in the wind.

Even if you aren't THAT serious, you need the panels and moldings on to keep your shoes dry so to speak.

Just my two cents' worth but I made a wish on both pennies before tossing them in. I hope others will offer their pennies also if I overlooked something.
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Old 04-08-2018, 12:43 PM
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IF lengthening that piece will allow the tailored fit you're after, OK but I might not opt to do it the middle, I'd probably go near the top to keep all the seams in one area.

This is where I'll probably start sounding like a broken record...

Yes, thats a problem spot on all of them and yes rocker and pillar placement are critical and come first.

The amount of space you have is WAY bigger than even what I have gotten used to seeing on these. If I ran into that, I would start back at square one and measure until I had eliminated all other potential causes besides faulty part.

From previous experience, I can tell you that if you are serious about being the guy with the one 2nd gen that has a lovely intersection of roof, fender, hood, door and on both sides...

You will have to have ALL bolt on sheetmetal installed, latched, and adjusted, including core support but excluding trunk lid.

No door hinge wear allowed.

Any rubber bumpers or seals that touch the hood should be in place. Yes, even the shaker seal presses on the hood so this is with engine in if you are serious.

Front subframe should be in, centered in it's small range of adjustment if applicable, and supported or on suspension.

Door and window seals should be installed, along with properly adjusted door glass.

Most importantly, the hood, fender, and door edge moldings plus any drip rail or windshield moldings MUST be installed or at least in place. The hood, fender, and door edge moldings MUST be lined up at this point or you are pissing in the wind.

Even if you aren't THAT serious, you need the panels and moldings on to keep your shoes dry so to speak.

Just my two cents' worth but I made a wish on both pennies before tossing them in. I hope others will offer their pennies also if I overlooked something.
Thanks, IDJ. While I got the notification that you had replied to this thread I was looking over at my first big thread where I replaced the DS full rocker and reading through a lot of your guidance there. Panel fitment was mentioned many times as being the primary guide in that thread too.

So, if I wanna get this thing on the wheels to get things loaded up am I safe to do it? The inside is braced well, the DS full rocker is welded in, I can screw the tail panel in place, and then start panel fitment before proceeding. I only hesitate to do that because it's so chopped up right now, but the inner bracing is good and at least I have both rockers now :-p

I really don't know how the a-pillar skin is off that far. The bottom and back edge of the door edge of the door line up with the new rocker and wuarter panel very well and uniformly across their entire lengths. It seems the only cause for being off so far is that the inner roof structure may have been welded on when not seated down all the way home on the DS a-pillar, but it sure seems to be. When I roll the window up the gap between its top edge and the inner roof structure seems uniform too...weird.

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Old 04-08-2018, 12:48 PM
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If I need to get this thing on the ground I'm gonna have to get the tires mounted on my wheels.

Btw, here's the DS rocker thread I referenced in the previous post: https://r.tapatalk.com/shareLink?url...8&share_type=t


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Old 04-08-2018, 01:37 PM
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The only thing I can think to reremind you of is that you need not weld a thing until every last issue you want to handle is resolved. I see you already welded some stuff but what I am trying to drive home is screws. If you just use screws, you can build the car right up to the last metal piece to fit. If that last piece needs the very first piece you hung to move, you unscrew and move it, try again. No commitment, make as many holes as you need. Totally eliminates the "I am damn sure I welded that where the old one was but now it doesn't fit this. The that is already there so I'll make the this fit instead of cutting that back loose." mental path. You just unscrew it all, do your detective work and give it another go until the truest solution blips your mental radar or becomes obvious.

In the absence of 3D computerized measuring equipment, trial and error is just how it has to be done. Just be glad that for example you don't have to be done with the roof and primed by the end of today, thats the world I dwell in.
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