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Hi, I lurk here a good bit and while I don't own a Colorado I have always liked them. I am just in a position in life where I don't have the time or emotional space for a project. I do have a few customers and friends who drive them and they let me have fun with them from time to time. Since I do use the site here is a way I hope to give back!:th_ontopic:

Ok so here we have a tailgate. you may notice I cut my filler panel overize and used a scribe to mark the outline. well I screwed up the first time and had to mark it twice.. oops. I also added a bit of crown and curve to the panel so it would not be a flat spot in the middle of the tailgate. I used an English wheel for this but a good bodyhammer working over an anvil or dolly will stretch the metal just the same. just be sure to stay away from the edges and hit evenly across the panel. a few extra hits in a line where you need it to curve while lightly lifting the edge with your fingers will help get this same shape.


then we remove the inner brace. just drill out the spot welds. I used to hate spot welds and I bought lots of fancy tools for drilling them out but nothing beats the versatility of a drill. low speed.

^you also can see that I went ahead and cut out the hole with an air saw. be sure to De-Burr the edges or they can mess up your welds and smoothness later.

nice tight fit sits snug in the hole without clamps or magnets. some tin snips are best for cleaning up any areas that need trimming. If you have a bit of a gap, Hammer the edge where you are short over a smooth dolly. it will stretch the metal out to a good fit. also clean both sides of the metal skin down to bare metal


I use TIG but Gas welding also works great. Mig welding is fine but you will have to hammer more later and the heat from grinding those harder welds will cause more work. place some tacks and hammer each one with a good heavy dolly held tightly to the backside. against the bodyline at the top I use a modified brad hammer that weighs about 3oz. be sure to hammer against the dolly to keep the panel in shape. welding shrinks a panel no matter how cool you try to keep it. it shrinks directly in the blueish area called the HAZ (heat affected zone). so hammering here brings the panel back into shape.

^see how the hammer is kept polished? this leaves little shinny spots on the metal so you know where you have hit.

Now that you have it tacked every inch or so by alternating sides lets make sure the panel is level and the surrounding area is smooth. if you see the metal sink and it seems to point to a specific tack go ahead and hammer that tack. DO NOT hammer anything other then the tack welds. DO not weld more until the panel is back to being cool, relaxed, and smooth. Problems only multiply.

so lets weld. weld about 1" at a time. as soon as your finished welding that inch put your torch down and pick up the hammer and dolly. if you hammer as the weld cools it cools it faster and it stretches the metal out at the same time. measure your hits and time it out so its all smooth about the same time its cool. overstretching can be a problem! end each weld on a tack. even if you start out in the middle between tacks. this gives a defined end to the weld, keeps you from going farther then an inch, and does an amazing amount to keep the metal from shrinking!

^see how smooth its staying.


I will post more pictures of this tomorrow when I finish but when its complete I should only have to put a good coat of primer over the area and sand it smooth. these tailgates tend to "hollow out" under the handle.

this same practice can be done to many things!

hood squirters. use a metal dowl pin to reach in for hammering against!


or whatever you decide to undertake on your truck! Bring back the crazy mods of the fifties!
 

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Discussion Starter #2

inch by inch its a cinch. just keep moving and use the hammer and dolly to bring the metal back up (or down) after each weld and before moving to the next weld!


the inside looks just as smooth from the dolly smashing the welds back flat!


ground, filed, and sanded. nice and smooth. you can keep working the metal smoother here if you want but at this point you get diminishing returns. (and run a higher and higher risk of overstretching!) or we can just apply a good healthy coat of epoxy primer and a touch of polyester dolphin putty before primer and paint. If anyone is interested Ill keep posting on this process.
 

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I don't weld but this was a really informative post -- thanks for sharing.
 

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Thanks for joining and sharing the info. Love to see custom stuff being done and love to see posts like this just as much, if not more. I personally have a goal to learn to weld, mostly for self gratification, but also because its yet another form of art that I enjoy.
 

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