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Discussion Starter · #1 ·
Hello! I want to remove the pitting and have been researching for a good way to do it. Many suggest similar approaches: clean, sand, polish, etc. The sand makes me cringe. Many suggest 400 then 600, some suggest starting with more aggressive grits. Does that sound right to you folks? If not, have you an alternate approach. Thanks!
 

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Hello! I want to remove the pitting and have been researching for a good way to do it. Many suggest similar approaches: clean, sand, polish, etc. The sand makes me cringe. Many suggest 400 then 600, some suggest starting with more aggressive grits. Does that sound right to you folks? If not, have you an alternate approach. Thanks!
The 400 and 600 will be enough to remove pits I would think and then go to finer grits after you get dine with 600. The finer the grit the more polished it will look. 1200 - 2500 grit for a polished look. But on another note if the pits are DEEP then I would leave it alone or go a different route. JUST my opinion though ! Others will chime in ! 👍
 

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Hello! I want to remove the pitting and have been researching for a good way to do it. Many suggest similar approaches: clean, sand, polish, etc. The sand makes me cringe. Many suggest 400 then 600, some suggest starting with more aggressive grits. Does that sound right to you folks? If not, have you an alternate approach. Thanks!
Picture would help like ponchonlefty suggested
 

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I have sanded out scratches and minor pitting in stainless and aluminum to take them to near mirror shine. By minor, I mean they were no more than 0.02" deep and mostly 0.005" or less. I have started with sandpaper as coarse as 220 for the nastiest of the pits or scratches. Otherwise starting with 400 is a good place to start. I have never sanded out an aluminum radiator and that is up to you. Trim and such does not hold a hot pressurized fluid like a radiator. If your pits are close to 0.005" deep (about the thickness of a sheet of copy paper)...it's probably OK to sand them out. What you need to be very cautious sanding at the corners or breaks. Those areas will be thinner by nature and you don't want to make them even thinner. Just don't sand areas that don't need it.

Wet sand with 400 until the pit/scratch is no longer visible. By scuffing it up with the sand paper, it may disappear to the eye, but still be there. Then wet sand with 600. The flaw may reappear as the 600 brings back some of the h surface. If 600 does not remove the flaw within you available patience, step back to the 400 then back to the 600...then 800. 600 or 800 should give you a natural-like finish, dull, but rather smooth. If going for a reflective shine, move on to 1000, then 2000, then polish it with something like Mother's. Spot sanding out pits will leave low spots that will show back up once the reflective shine is brought back. If ripples or divots end up being too noticeable due to the shine, you can go back to to the 600 or 800 and dull it back down. Keep in mind the more you sand the thinner the aluminum gets.

If you take to sanding on it, just know you will be sanding and rubbing for longer than you think.
 

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Discussion Starter · #6 ·
Hi, here are the photos but I'm not sure they will do any good. Between the sun and the reflection, detail is compromised...worse in the garage with a flash. In any event, the brown tinge in all of them is a reflection of the hood insulation, not the pitting. You can see the pitting in a couple of the shots, small dots, not clustered very much in the photo. More clustered when viewed directly. Depth is not too bad, my fingernail just barely gets caught on them. I appreciate the advice so far and look forward to some additional thoughts. Thanks!
 

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Discussion Starter · #7 ·
I have sanded out scratches and minor pitting in stainless and aluminum to take them to near mirror shine. By minor, I mean they were no more than 0.02" deep and mostly 0.005" or less. I have started with sandpaper as coarse as 220 for the nastiest of the pits or scratches. Otherwise starting with 400 is a good place to start. I have never sanded out an aluminum radiator and that is up to you. Trim and such does not hold a hot pressurized fluid like a radiator. If your pits are close to 0.005" deep (about the thickness of a sheet of copy paper)...it's probably OK to sand them out. What you need to be very cautious sanding at the corners or breaks. Those areas will be thinner by nature and you don't want to make them even thinner. Just don't sand areas that don't need it.

Wet sand with 400 until the pit/scratch is no longer visible. By scuffing it up with the sand paper, it may disappear to the eye, but still be there. Then wet sand with 600. The flaw may reappear as the 600 brings back some of the h surface. If 600 does not remove the flaw within you available patience, step back to the 400 then back to the 600...then 800. 600 or 800 should give you a natural-like finish, dull, but rather smooth. If going for a reflective shine, move on to 1000, then 2000, then polish it with something like Mother's. Spot sanding out pits will leave low spots that will show back up once the reflective shine is brought back. If ripples or divots end up being too noticeable due to the shine, you can go back to to the 600 or 800 and dull it back down. Keep in mind the more you sand the thinner the aluminum gets.

If you take to sanding on it, just know you will be sanding and rubbing for longer than you think.
Thank you. Is a variable speed sander too aggressive?
 

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I would highly suggest just using your hand and fingers. I say this because your situation looks very minor from your pics. Sanders will tend to dig deeper into the aluminum and you will spend more time sanding out the sanding scratches that the sander puts in. Your hands and fingers will do less gouging. I have used the palm sanders to get started on things like this and find that it has left deep swirl marks that take even more time to sand out once the shine starts to come back. This is assuming you are going for a nice reflective finish. A sander can leave a very nice dull brushed-like finish, but it adds work if you are going for that mirror finish it once had.

I suspect you will spend at least 4 hours bringing the top of a radiator back to mirror finish from the look of your pics and that the pits can be slightly caught by a fingernail.

Tip: If you are going for a mirror finish without ripples or distortion. Find a flat paint stick and cut it short, about 2 inches long, wrap your sand paper around it and use that as a sanding block. This will remove the aluminum in a flat sense keeping the surface level. Without that, you will concentrate on the pits with just your finger tips and the results will be low spots in the aluminum where the pits were. Once shined up, those low spots will look like a circus mirror.

Restoring old brightworks is not for the impatient, but rather for someone who has more time than money...willing to save a piece rather than buy a new one. Trust me, I know, I have saved a lot of money on my 67 build, but I bet I made $5 an hour doing it compared to the cost of new repop parts.
 

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I would highly suggest just using your hand and fingers. I say this because your situation looks very minor from your pics. Sanders will tend to dig deeper into the aluminum and you will spend more time sanding out the sanding scratches that the sander puts in. Your hands and fingers will do less gouging. I have used the palm sanders to get started on things like this and find that it has left deep swirl marks that take even more time to sand out once the shine starts to come back. This is assuming you are going for a nice reflective finish. A sander can leave a very nice dull brushed-like finish, but it adds work if you are going for that mirror finish it once had.

I suspect you will spend at least 4 hours bringing the top of a radiator back to mirror finish from the look of your pics and that the pits can be slightly caught by a fingernail.

Tip: If you are going for a mirror finish without ripples or distortion. Find a flat paint stick and cut it short, about 2 inches long, wrap your sand paper around it and use that as a sanding block. This will remove the aluminum in a flat sense keeping the surface level. Without that, you will concentrate on the pits with just your finger tips and the results will be low spots in the aluminum where the pits were. Once shined up, those low spots will look like a circus mirror.

Restoring old brightworks is not for the impatient, but rather for someone who has more time than money...willing to save a piece rather than buy a new one. Trust me, I know, I have saved a lot of money on my 67 build, but I bet I made $5 an hour doing it compared to the cost of new repop parts.
Spot on 😉👍
 

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1970 Pontiac
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I would highly suggest just using your hand and fingers. I say this because your situation looks very minor from your pics. Sanders will tend to dig deeper into the aluminum and you will spend more time sanding out the sanding scratches that the sander puts in. Your hands and fingers will do less gouging. I have used the palm sanders to get started on things like this and find that it has left deep swirl marks that take even more time to sand out once the shine starts to come back. This is assuming you are going for a nice reflective finish. A sander can leave a very nice dull brushed-like finish, but it adds work if you are going for that mirror finish it once had.

I suspect you will spend at least 4 hours bringing the top of a radiator back to mirror finish from the look of your pics and that the pits can be slightly caught by a fingernail.

Tip: If you are going for a mirror finish without ripples or distortion. Find a flat paint stick and cut it short, about 2 inches long, wrap your sand paper around it and use that as a sanding block. This will remove the aluminum in a flat sense keeping the surface level. Without that, you will concentrate on the pits with just your finger tips and the results will be low spots in the aluminum where the pits were. Once shined up, those low spots will look like a circus mirror.

Restoring old brightworks is not for the impatient, but rather for someone who has more time than money...willing to save a piece rather than buy a new one. Trust me, I know, I have saved a lot of money on my 67 build, but I bet I made $5 an hour doing it compared to the cost of new repop parts.
I have done body work off and on since '82 but not a professional 😂😂. I tell people that I am better than some..... but not as good as others !!! 😊
 

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1970 Pontiac
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132 Posts
I would highly suggest just using your hand and fingers. I say this because your situation looks very minor from your pics. Sanders will tend to dig deeper into the aluminum and you will spend more time sanding out the sanding scratches that the sander puts in. Your hands and fingers will do less gouging. I have used the palm sanders to get started on things like this and find that it has left deep swirl marks that take even more time to sand out once the shine starts to come back. This is assuming you are going for a nice reflective finish. A sander can leave a very nice dull brushed-like finish, but it adds work if you are going for that mirror finish it once had.

I suspect you will spend at least 4 hours bringing the top of a radiator back to mirror finish from the look of your pics and that the pits can be slightly caught by a fingernail.

Tip: If you are going for a mirror finish without ripples or distortion. Find a flat paint stick and cut it short, about 2 inches long, wrap your sand paper around it and use that as a sanding block. This will remove the aluminum in a flat sense keeping the surface level. Without that, you will concentrate on the pits with just your finger tips and the results will be low spots in the aluminum where the pits were. Once shined up, those low spots will look like a circus mirror.

Restoring old brightworks is not for the impatient, but rather for someone who has more time than money...willing to save a piece rather than buy a new one. Trust me, I know, I have saved a lot of money on my 67 build, but I bet I made $5 an hour doing it compared to the cost of new repop parts.
I have an air file we call it but never use it to hard to control.....had a fairly hard rubber bottom wooden file board that I really liked but somebody light fingered it ! And now I have gone back to a paint stick like I started out with in the 80's 😂😂 paint sticks are fairly cheap and nobody steals them 😉👍😂
 
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