Mark Simpson

Straightening and Polishing Aluminum

Mark Simpson
Duration:   12  mins

Description

Straightening and repairing aluminum trim pieces can seem like a daunting task, although many of the same skills and processes you use to refinish car body panels are also used when straightening trim. Mark Simpson demonstrates the process of removing dents and scratches and returning a luster to trim pieces by polishing aluminum.

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5 Responses to “Straightening and Polishing Aluminum”

  1. Dennis Kennedy

    Great information! How do you recommend removing the anodizing?

  2. Dan

    I think it would have helped to mention the rotation of the buffing wheel in relation to the piece and how easy it is to get it caught on the buffing pad. Safety first!

  3. Keven

    It sure would be nice to see things closer. Up close camera work has been lacking on many of these videos, but this one is really bad. I can't see anything when he tries to get the dents out.

  4. Richard willing

    Looking for crome for 63 Galaxie 500 2 door hard top

  5. rxcowboy

    After the anodizing has been removed, what is the best way to keep the polished piece from dulling over time.

When working on any classic car, a lot of cases where you're gonna run into aluminum parts. Aluminum is a relatively easy material to work with. It's soft to move, it buffs up and polishes real easy. The only hindrance can be is sometimes dealing with coatings and anodized coatings and we've removed that already on this piece. And we're ready to actually start the process of restoring this piece in itself. To do that we'll remove the dents, we'll sand out the scratches and get it ready to buff. Okay. To start, we're gonna like actually remove some of the dents and some of the dings in here. And, you know, we've got like a little high spot coming from the backside and the way we get those out is just... The same method that we used in basic body filling and work. Again, we have sort of a texture on this surface so we don't want to get out here and just wail on this because then we'll end up flattening out this texture. So we wanna go very soft and very, you know, Slow about it and slowly bring the finished back to where it needs to be. This also relates to high spots. As you see here we have a little spot here on the backside where it's actually pushed through towards the interior. And... In order to get that to come down we'll have to actually just kind of go in and we can tap it with the hammer a little bit. Again, this is aluminum. You want to be real slow and real careful about moving the material too fast or too much. And with aluminum usually the biggest concern is because aluminum work hardens real easy and it will actually fatigue and crack unlike steel. Steel with fatigue and crack too but it takes a lot more work to do it. With aluminum the tendency, if you really gotta bend a piece a lot you may want to actually heat it up and anneal the aluminum before you move it too far. And what that does is relaxes the structure in the aluminum itself. And we're just gonna keep working out some of these small dents. Here, where we've taken this one down, we've brought this high spot down. Our next step would then be to actually go in and we'll use some 600 grit sandpaper and just a regular paint stick. What this gives us is a nice solid firm surface to work the sand from. And we can come in... And actually sand that place where we've worked it. You can see where we've still got a little bit of a high spot there. We'll knock that down just a little bit more and then sand it some more. Also got some deep scratches that we're gonna actually just sand out. You know, there's things with the anodizing gone we can go in and actually sand off all of the... Scratches and get the surface real smooth. You know, whether you're doing, here it's a interior door panel piece, even if you're doing like outside trim on a lot of the cars of the late 60s into the 70s, they had switched from using stainless steel for a lot of their trim to actually using anodized and flash plated aluminum for the trim panel. And of course it was cheaper than stainless but requires just a little bit more work to actually get them to clean up. And it's really not a labor intensive process but more of a time-consuming. Kind of a little bit of a putsy process. I always contend it's a good project for in the shop when you got the game on the TV and you can just not have to think about what you're doing for a long time. Because it is kind of a little bit time-consuming to actually get the surface all sanded out. We're gonna just kind of work on this end on this piece for this video to show you how the process is done. Again, we're using 600 grit sandpaper. I don't suggest anything, coarser than that, just because you don't want to end up leaving a lot of scratches. Aluminum does buff out real easy, but you don't want a bunch of deep scratches where you have to remove a lot of material to actually get the scratches out. You can see it as the water kind of turns black as the aluminum is getting removed from the surface. You know because this is right above the inside door handle and it gets a lots of small scratches in the anodizing that needed to actually get sanded out and polished up. And it's a good idea to wipe down your surface, check it real well every now and then, see how your progress is coming. You know, the great thing about this if we get all the way to the point where we're buffing it out and we see something that we wanna address a little bit more, you can just go right back in, straightened parts of it and rebuff it up then at that point. Just a little bit more. Almost got that. There was a deep scratch in here probably from when the door was... There's a chrome piece that slides along the top of this that if you're not careful when you're actually putting it in place, you can scratch the edges of these moldings. And it's not uncommon if you see on this particular car where the the cuttings of the way it's designed that it a lot of them have scratches in the same spot. Okay, I think we got pretty good. Like I say, if we get into it and we start buffing we see when he got to do it more, it's just a matter of grabbing the sandpaper and sanding it a little more. Next, we're going to move from a 600 grit to a 1200 grit. This will help refine the surface, make it a little easier to buff, take out some of the sanding scratches left by the 600 grit. And generally, when you're working this, when you're taking the dings out and the dents out, if it's just a little bit high, when you start the imperfection, when you actually start sanding, it'll take off the high spots and it'll kind of even things out. Whereas, if it get dings in there that are too low, there's like pretty much no amount of sanding that's going to take those out. So you should go back in and use your hammer and dolly or you can use like nylon pride tools and stuff like that to actually just smooth out the rough spot. Like I say, aluminum will move really easy. Most people are aware of that. So you don't need to use real aggressive tools to actually get it to shape and form. Once you're happy with how you've sanded it out and how smooth it's gotten, you're good to go to go straight to buff at this point. And when I'm buffing aluminum, I usually don't use anything more aggressive than... I usually do all my defect removal with the wet or dry sand paper. When it comes to actually polishing, then I can use just a white Rouge, which is type of buffing compound that is really fine and it'll put a good luster on it. And then use a loose buff on the buffing wheel. Cause you don't need to be real aggressive with aluminum because it will move fairly easily. We're going to just buff out this corner here. Kind of show you in comparison to the raw stripped of anodizing aluminum, and then the sanded and buffed area. There you can see a quick comparison. Here was the the stripped of anodizing bare aluminum and just a little time on the buffer. You know, we've got a nice, good luster to it. This is a very acceptable finish for the inside of the car. And like I say, it just takes time a little bit of patience and we'll have the rest of this piece looking just as good and you should get out in the garage and start buffing your own pieces.
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