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crazy opeler
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Discussion Starter #1
Using fiberglass is a viable solution as long as it is done correctly. You MUST remove all of the rusted metal first, but you have to do this anyway if you are going to weld new metal in. Also the most crucial part is insuring that it is sealed up properly, you must make it so that water cannot get between the fiberglass and the metal.

You say that this car has bondo on it? if the bondo is already partially covering rust then the car is rusted pretty badly and you will have a lot of metal to cut out. However if the floors are solid then the car probly wont be all that much trouble to repair.
 

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Another concern with fiberglass: Polyester resin does not bond well to metal, especially rusted metal. If you are going to go this route, use epoxy resin. The polyester resin is more brittle, and water tends to get between the base material and the polyester/fiberglass matrix. The patch will then fall off!

I'm not saying fiberglass can't be used, it certainly can. But even if I am bonding a polyester/fiberglass part to steel (such as the addition of flares for example), I will use epoxy as the bonding agent.

Bob
 

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TempusMori, My two cents is to try to find as rust free a car as you can unless you're buying it for parts. For all the rust you can see there's probably 10x as much you can't see and I imagine Canadian winter's are not kind to cars.
Bodie
 

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TempusMori,

Kelowna? Sheesh, it sounded like you were in Outer Mongolia! That's not exactly NYC, but it's a far cry from the hinterlands. It's only a 7 hour drive from me here in Calgary. I get there fairly often to ski at Big White, and I have several friends there. And I know of a couple of GT's nearby. One in Trail, and lots in the Vancouver area.

The good news is that, compared to the eastern seaboard or the road salt kingdom, Toronto, the climate is far more considerate in Kelowna. It's kind of a temperate desert. So perhaps this GT won't be as rusted as I surmised. As Chris Blust (Opel73) points out, check the floorboards, as they are a very good initial indicator of overall rust. If the floorboards are largley rotted, run, don't walk. But if they are OK, look at other key places like the jack points (the round tubes at each inner wheel corner, along the sides). And finally look at the door skins, especially along the bottom edge. If those spots are only slightly rusty, so that you can see rust but not poke a screwdriver easily through, then you might have a car worth fixing. Typical rusty spots, but not terminal, are the outer rocker panels, behind the wheels, and especially the top of the front fender just behind the wheel, where mud gets trapped on top of the inner fender. Those spots get rusted in even the most gentle climates, except perhaps California, Arizona or Nevada

Where I DO disagree with Chris is his suggestion that fiberglass is an acceptable method of repair. If you happened to be talking about professionally manufactured replacement panels, such as Stanley's tail and nose panels, or belly pans such as you buy from OGTS, or wheel flares and such, then I agree. If you are talking about cutting out the rotted metal and filling the cavity with steel wool or fiberglass insulation, and then laying up a couple of layers of glass cloth with resin (even epoxy, of which I have lots of experience), then you are wasting your time.

One suggestion I have is to borrow a digital camera and post a few photos of the GT on this site. Although it's not by any means certain, a picture is worth at least a thousand words in describing its condition.

Again, good luck, and if we can help you with your decision, please ask.
 

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Digital Camera

That is actually I good idea. I have access to a digital camera. When I have time I will go there and take a few pics. As for under the car, there is rust but the floor in the front of the seats seems solid when stomped on. It gave a good sounding thump and it did not seem to have any give.
 

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crazy opeler
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Discussion Starter #6
kwilford said:
TempusMori,
Where I DO disagree with Chris is his suggestion that fiberglass is an acceptable method of repair. If you are talking about cutting out the rotted metal and filling the cavity with steel wool or fiberglass insulation,
Don't ever put steel wool or fiberglass behind a patch that will only trap moisture and cause it to rust faster.
The fiberglass cloth stuff is what I am talking about, and it will only work on small rust holes that won't need a backing, if you have a decent backing then what do you need the fiberglass for?
I think that this method is acceptable at best.
I myself weld in new metal and use fiberglass epoxy resin to smooth it out, I then seal it from the inside with a special body seam sealant that I got from eastwood.
 

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Welding

I know the basics of welding, I have taken a few metalwork courses in school but I have not idea about the specifics of welding on cars. Do I use a mig or arc welder? Or what about the Oxy torch? To cut out the rust do I use a disk grinder?

I have never done any car bodywork and my knowledge of car mechanics is limited, I have never done any serious work on a car. Any advice would be appreciated.

How about some books that I should read?
 

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crazy opeler
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Discussion Starter #8
It is my recomendation to use a cutoff wheel to cut out the rust, a cutting torch may warp the metal. If you have access to a plasma cutter then use that.....and I envy you.
as for welding I have had good luck with mig welding, that is what most body repair manuals suggest.
 

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I am going to split this thead, and move this part to the "Body" heading.

Use a grinder or coarse sanding disc to knock down the rust and help find the "good" metal. I have just used aviation shears to cut out the rusted panels, but wear leather gloves, because the panel edges are very sharp (and I have the stitches to show for it!). As Chris says, use (borrow, buy, rent) a MIG welder. Try to get a "gas" version, since the "gasless" (flux-core) makes it much more difficult to get a decent weld with out burning through the sheet metal. And see if you get a "flanging tool". Mine just connects to my pneumatic hammar, but I have seen hand actuated models. They make a slightly depressed edge on the car panel, about a 1/4 inch wide, where the new metal sits in. It reduces the depth of the repair. Then tack weld the new panel in, and finish by welding the seam all around. Look at Bob Leger's ITB Ascona work at:

http://www.opelgt.com/forums/showthread.php?s=&postid=4965#post4965

And the photo below. Bob is talented enough with his MIG that he is butt-welding sheet metal, but I suggest that you "lap" the joints, and clamp it with a vice grip while it is being tacked.

There are many good books on the subject, and the Internet is full of resources, and PRACTICE is always good. But it helps to have a good start, so ask away!
 

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crazy opeler
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Discussion Starter #10
I forgot about that flange tool,
I also have the one that connects to a pneumatic hammer; however I have never had any luck with those. The GT has too many compound curves in the body for that tool to be very effective, and it ends up bending and warping the metal in ways that you don’t want. In my opinion those flangers are only good 0n totally flat body panels, for example it worked wonders on my Jeep CJ-5.
 

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Mig Welder

What kind of mig welder would be recomended to work on sheetmetal? Someone told me to get a small 110 Amp, will that be too weak? How about that 90 amp mig that Sears sells?
 

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Bad News

As it turns out my father has been talking to someone and they informed him that the Opel GT is abnormally prone to rust and will need constant repair. So now if I do get the GT I will have nowhere to put it or work on it because I am schooling right now and have no other place to put it. Is what he is saying true? Is the GT a car that I would be able to fix up and use as a commuting car?
 

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crazy opeler
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Discussion Starter #13
The gt is prone to rust, BUT if the rust is irraticated, and you fix it properly, you should have another 10 years of good rust free driving in a cold invironment such as you are from. After fixing rust you have to take some steps to prevent it from coming back, por-15 for example.

also the GT is way less prone to rust than say a MG or a Jaguar, the metal used to make the GT was thicker and a better grade of steel.
 

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it is a 30 year old car...

Let's not forget the REAL rust buckets from the '60's and '70's: VW, Honda, Isuzu, anything Itilian or French.....

Being prone to rust really doesn't matter if you get one in decent shape and take the required precautions, ie. undercoating and using POR 15. Yould you not buy a blue car with a good paint job just because blue paint tends to fade more than other colors?
 

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Rust Prone

First question, welder type? I just took a seminar on MIG welding at the Vintage Sports Car Club of Calgary, so I am FULL of information, and a few opinions. Some of them mine, most are from the 40-career year welder who put on the seminar.

If you are doing body work, you need the best MIG welder you can afford. Specifically, a gas-type welder, NOT a gas-less (flux-core) welder. One that does both is good, but is not as important for body work, where you NEED the shielding gas to minimize heat affected area, and thinner wire to minimize burn-through. The cheap Sears welder is, well, CHEAP! And won't work nearly as well as a decent Lincoln, Miller, or Hobart. And don't get a cheap Italian or some other third-world country welder, as the first time you need parts, they won't be available. Clarke is the better of the cheap welders, but won't offer some of the features I mentioned above. If you are buying a "Store-Brand" such as Craftsman (Sears), or MotoMaster (Canadian Tire), or even Campbell-Hausfield, ask who actually makes it, and where.

Amperage isn't as important as the quality and features of the welder, so that it has such things as an infinitely variable voltage control (they might call it "Heat Selection") and variable (not stepped) wire speed, which also controls amperage in most MIG welders. Most decent welders will be at least 100 or 125 amps, with better ones at 135 to 150 amps. But at full amperage you may need a 20 amp-110 volt circuit, or even a 20 amp-220 volt supply, while household circuits are only 15 amp-110 volt. A good 110 amp MIG is better than a cheaper 135 amp unit, at least for body work. Rule of thumb for stick arc-welders: thickness of the material being welded in thousandths of an inch equals required amps. One-eighth (0.125) inch thick metal requires 125 amps. MIG welders require as much as twice that (depending on wire size, voltage and speed), so MIG welders are NOT very good at welding thicker steel, such as structural tubing or even angle iron. Most body sheet metal is 30 to 40 thousands thick, so you need at least 90 amps. And thin wire (0.023 or 0.025 inch) is better than thick wire (0.035 inch) for body work.

How much will it cost? At least $600 CAD from your local welding supply store, plus another $150 for the gas flow meter, and another $150 for the gas bottle (which you can lease, but it will pay for itself in less than two years. Which goes by VERY quickly!). Cheap units can be had for as little as $400 CAD, but they will be gas-less only, stepped voltage (as few as 2 choices), and maybe even a stepped wire speed. They can be used, at least to make molten pools of metal, but they will NOT provide a quality weld.

That's enough for the first question about welding.

HTH
 

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Second question: is the Opel GT rust prone? Sure, but not in a Fiat sort of way. Not even in a Datsun (Nissan) 240-Z way. There are some inherently rust-prone areas in the GT, such as have I mentioned above. But in those parts of the world that don't have tonnes of salt-laden slush, Opels can last forever. And even in our northern climates, they can last a very long time. I grew up in Winnipeg, where I originally bought my GT in 1978 while I was in University, and it carried me through 4 long, cold, salty winters. It was a GREAT winter starter, even at -40 F. Which is the same as -40 C, and too damn cold to expect anything to start.

When it came time to "restore" it a few years later, I had to re-construct the rear wheel arches, and the rockers and front fenders, but the floors and frame rails were sound. Which is what is really important.

Should you buy it so you have wheels while you go to school? That depends. I drove mine throughout university, and fixed it up (new paint, minor bodywork, Weber carb, etc.) during that time. But it was only 7 years old back then, and only had 58,000 miles. As I said in my first post on this subject, 30 year old cars are NOT good daily drivers, if you have to rely on them. Unless it is in extraordinarily good condition, or you are a very gifted mechanic with lots of spare time, and low expectations of reliability. Not to mention long delivery times for some parts, if they are coming from the States.

And you say you don't have anywhere to work on it? Not even your dad's garage? Kelowna has very nice weather, by Winnipeg standards, but you still get WINTER! Maybe you should buy a '91 Civic and wait until you graduate before you buy an Opel GT. Or buy the GT now, and an '87 Cavalier, and fix the Opel up while you wait for the Chevy to fall apart.

JM2CW
 

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From my own welding experience...

All above is great.

Most body thickness metal can be welded in the 65-95 amp range, so a 110 amp unit is not really limiting you.

Look for used units. The cheap ones won't have held up, and the good ones will usually come with things like the gas regulator, helmets, gloves, and the like. All of those little things that add up. I bought a middle of the line Lincoln wire-feed for $250US for a friend 3 weeks ago. The guy threw in a Lincoln 225 stick welder (my personal bang-for-the-buck favorite in stick welders) for an additional $75 with almost $75 worth of rod. My friend can now do almost anything automotive for less than $350.

Keep an eye out in papers and on the internet, and visit shops that might be upgrading. The welders above were bought from a muffler shop that had upgraded to a unit with a plasma cutter, so they didn't need the old stuff anymore and had already written it off as a business expense.

My current welders include a '40's vintage 220V unit I refurbished that cost a total of $35, a Lincoln 225 for normal day to day work, and a Miller wire feed with VERY fine wire for body type work. I actually use the stick welders for anything larger than and including exhaust pipe.
 

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You remind me of myself when I was 16 and found a 37 Ford pickup...
If you really want to become able to do such things, you have to start somewhere, huh? I encourage you, but here are some basic warnings.
Your project could take a long time. Meanwhile you need something to drive.
Projects like yours need a home, it is real frustrating trying to do this out in the backyard (weather) or in Dad's garage (sparks, smoke, noise, mess will get you and your GT evicted). You need a little shop dedicated to your project.
Tools and equipment. Maybe you can borrow some. Maybe you have to buy some. Seriously, you could have thousands invested in what you need to get started. If you are really into it, the GT is only your first of many projects to come.
Which leads to experience. You can do this if you really want to and will quickly tell yourself how you'll do it differently the next time!
Watch "Monster Garage" on tv. These guys are pretty clever and quite talented! Notice they have to scratch their heads a lot and don't always get it right on the first try. When you get stumped, stop, sleep on it and it will come to you. The first instinctive action might cause more damage!
Go to a local body shop and ask if you can look at how cars are repaired. Notice they can be cut apart and welded back together, sometimes they even look right and are drivable!!
Read Hot Rod Magazine. See the step by step pictures of how perfectly good cars are cut into a zillion pieces and then are welded back together to take on an interesting new style! Now that is craftsmanship.
Unfortunately, lots of projects don't get done. But experience was gained.
Oh, here's a big one. Only do this to a car you plan on loving forever, if you decide to sell it you'll be very disappointed in how little you'll get for it. Buyers have no respect for how hard you worked to make it so sweet unless they have done it themselves at least once.
I could go on and on, could tell you lots of hot rod stories, but not tonight...
 

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crazy opeler
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Discussion Starter #19
I actually know a guy who goes to Purdue that has been driving and fixing his car ever since he came here.
as for the investment in tools you don't NEED a welder, you can always pop rivit the panels in ($15). And other than that all you really need is a good DA sander and an air compressor. Their arent really any other specialty tools( I assume you have a socket set).
While I restored my first GT I was employed by a local tool rental so I got everything I needed to make the process smoother. On the other hand I usually ended up doing things by hand then using some specialized tool.
 

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Finding out the hard way...

Just thought I'd throw in my two cents here...maybe prevent someone else from getting screwed.

Over this past summer I purchased what was supposed to be a rust free GT from New Mexico. It was basically a rolling chasis so it would have been perfect for me as I already have a good donor GT. It cost me $1000. Of course I went to see it...looked it over...even took a magnet to it to make sure there was good metal there. I didn 't realize; however, that a magnet will still stick very well THROUGH BONDO!! I got the car home at a no small expense and started tearing it down for painting only to find rust around the fenders that was coverd with bondo and several large dents also covered by bondo. In fact, the entire car seems to be coated with a thin (in some areas thick) layer of bondo.

So basically I ended up with a pig in a poke and am now trying to figure out if I should have the thing media blasted to pull off all the bondo (I'm scared about what else I will find) and weld in new sheetmetal, or if I should just call it a day and cart it off to the salvage yard.

Moral of this story: BEWARE OF BONDO! Take any car you plan on buying to a body shop, or have a body guy come with you to see the car...before you buy!

Good luck,

A disgruntled multiple GT owner
 
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