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Old 04-17-2012, 12:40 PM   #26
CMACDONALD1
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Re: Blazer top sag / repair

Just another thought I had was cutting the roof skin off of a suburban and using duramix panel bonding glue to attach. A guy would need to find a toasted suburban of course. let me know your thoughts.
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Old 04-17-2012, 02:24 PM   #27
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Re: Blazer top sag / repair

I think that idea is much better than cutting the top layer off and trying to fix it...

If it would fit right on top of the blazer without any mods (kind of a cut and glue type of deal), that's definitly something to look for!
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Old 04-17-2012, 02:56 PM   #28
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Re: Blazer top sag / repair

If you had some mad fab skills, you could just cut of the entire Burb top, shorten it and make a metal hardtop. It would probably even be lighter than the fiberglass one, haha!
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Old 04-17-2012, 06:10 PM   #29
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Re: Blazer top sag / repair

and get right caried away with some barn doors on the back!!!
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Old 04-17-2012, 06:21 PM   #30
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Re: Blazer top sag / repair

Oh man..wouldn't some tailgate barn doors look cool?...
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Old 06-11-2012, 01:04 AM   #31
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Re: Blazer top sag / repair

Quote:
Originally Posted by BOHICA View Post
No, probably not. With a stanchion in place, you're bracing the inner panel off of the floor and using all of the pressure from the foam to force the top panel up. However, once you remove the support, the pressure will be divided between the top and bottom. The most likely result is that once everything settles, you'll achieve mixed results. The roof probably won't sag as much, but the ceiling will.
What about reversing the gravity affect by flipping it upside down while it cured?
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Old 01-10-2017, 12:34 AM   #32
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Re: Blazer top sag / repair

Old thread but any updates on how to repair?
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Old 09-05-2017, 12:16 AM   #33
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Re: Blazer top sag / repair

Digging this one back up for anyone still wanting to attempt this... My top had 6 distinct areas that were sagging pretty bad and there was no way I would have been satisfied with the top after putting so much work into the rest of the truck. In the picture below you can see the 3 sections I cut out on the one half and the 3 sections on the other half that are sagging as outlined by where I sanded.

So I've started repairing the sags and it looks like this method will work out pretty well and it really isn't difficult. I fixed 2 of the 6 sections as a test and ordered some more materials to do there rest.

1. Cut out the sagging areas between each of the internal supports being careful not to cut through the inside layer. As you can see it was really easy to tell where the supports were on mine before making the cuts.

2. Glue a 1/2 thick piece of rigid foam insulation where you cut out the section.

3. Use a block sander long enough to span across the supports to cut the foam down to shape. The the sections of the top left over the supports acts as you guide so it's easy to shape the foam.

4. Fiberglass over the foam using woven cloth and epoxy resin.

To start with I used a couple of the small packs of the bondo brand fiberglass cloth just to try this method out. I'm satisfied with how it worked out so I've ordered a larger roll of cloth so I can cover the whole top with a single piece. I recommend getting enough cloth to cover the whole area from the start if you decide to attempt this. The small packs are a rip-off, the two areas shown below are the exact size of what come in the packs and I did 3 layers. So that was three packs and they are like $6 each at lowes. In comparison I ordered a 60" x 30 ft roll of cloth for $40 which is enough to put 4 layers across all 6 areas at one time.

I'm also considering molding in some raised ribs while I'm at it. It'd give it a little extra strength and possibly serve as a roof rack.

I'll post the finished product once complete.
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Last edited by stangtjk; 09-05-2017 at 12:22 AM.
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Old 09-05-2017, 12:45 AM   #34
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Re: Blazer top sag / repair

Also I believe the last image of the blue prints on post #4 that is identified as single wall top bracing is incorrect. That apppears to be the bracing between the two halves of the double wall top and they are made of fiberglass.
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Old 09-05-2017, 12:52 AM   #35
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Re: Blazer top sag / repair

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Originally Posted by jeffg1010 View Post
It will probably be a while. But it is definitely the plan. And I will definitely to a thread about it

Does anyone have an idea of how much of a gap there is between the top layer and the bottom layer? I would guess an inch? But I'd like to hear from someone who has cut into one.
It's less than 1/2"... Mine was sagging bad enough that the top layer was almost touching the bottom layer. You could push in the center of the sagging and hear them bump together.
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Old 05-27-2018, 11:05 PM   #36
NorthernMatthew
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Re: Blazer top sag / repair

I think I might benefit by being able to access that assembly guide.
Thanks a bunch for sharing.
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Old 11-07-2018, 08:33 AM   #37
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Re: Blazer top sag / repair

Hi Northern Matthew;
I have this assembly manual,but is somewhat difficult to follow,no consistencies,The portion I would like to find info on is how does a person change out the bottom rail that has the hold-down anchor bolts? Do you have to cut out the entire rail, aluminum I think, then build a steel rail with captured nuts, then resurface the SMC outer layer? I have a good top, just the anchor bolts are rusted from the inside. Thanks for looking,any suggestions!! Tomq
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Old 11-19-2019, 08:19 PM   #38
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Re: Blazer top sag / repair

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I have a couple of both single and double wall tops.. the doubles sag worse than the singles.
I hate to say it but the "trusses" you see in the blueprints are not metal.. they are simply 1"X2"s .. yes.. they are wood!!

Reason I know this after stripping the texture off of the single wall top to smooth it out, I found a lump and a crack on the passenger side above a "rib" so while grinding it down I hit wood.. Whoa!!

I really pondered taking a die grinder and cutting slots from side to side and removing the wood trusses and then propping up the sags from underneath and epoxing in new steel 1X2 rectangular tubing then refinishing it all. But I already had over 40 hours in smoothing it and decided to live with the sags.

Just remember if you do any repairs to any of the tops, They are not the "normal" fiberglass, they are made of SMC and do not have a gel coat, this requires different materials to repair, If you use regular polyester resin it will fail over time!..
The best materials to use are SMC formulated resins. Or epoxy.. also when you go to paint it. make sure the very first coat is epoxy primer and not urethane as it will not stick.
Thank you for info!
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Old 11-19-2019, 09:01 PM   #39
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Re: Blazer top sag / repair

Just noticed I never poster the results.
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Old 11-20-2019, 01:58 AM   #40
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Thumbs up Re: Blazer top sag / repair

NICE work!
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Old 11-20-2019, 12:43 PM   #41
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Re: Blazer top sag / repair

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Originally Posted by stangtjk View Post
Just noticed I never poster the results.
Awesome looks great!
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