Need help with sanding advice

[JuniorNA]

Heh guys / I'm trying to do what other people make look so easy ! I just can't get my mod to the mirror finish I want

I used an ego battery as a test - used 800 grit to get all the rubber out - used 1000 grit to see some shine - used 1500 grit hoping that would be it but I still see tons of scratches that my 1500 isn't removing

So I figure I need flitz metal polish (not sure if its an abrasive or not but I'm getting no results. I have a pretty decent mirror finish but I see tons of little scratches from top to bottom .

Then I put up and ego adapter and put it to the drill and ran it for a few minutes while using 1500 grit - shine is first - ill post pic but I still see scratches.

The scratches were from me when I tried to remove the rubber coating but I thought the 1500 grit would have removed them and maybe then shiny

Here is another example of a Penelope clone - it's new so new scratches - I used a buffing wheel and my dremel for 10 min and nothing changed

So I need a little help removing those light scratches

 

[Chip_]

... but I still see scratches.

In Lapidary (I shine my rocks), we don't remove scratches with the buffing wheel. It ain't gonna happen.
We take our rocks and bring em through the various grits of grinding/sanding.
At each stage we make sure that all the scratches are the same size, before proceeding to the next grit size. If you don't, well you end up with scratches at the end of the final buffing stage.
In other words I start at maybe 60 grit, make sure all the scratches are the same size before jumping to maybe 150 or 200. Then I make sure all the scratches are the same size at the 200 stage, so on and so forth.

If your 800 grit size had some scratches that were deeper than the 800 scratches, then you need to drop even lower, until you find the depth at which those pesky scratches are at.

One other hint, make sure that everything is clean before advancing to the next grit size. Even one tiny little grit from the previous stage will leave you with those pesky unwanted scratches.

Good Luck.

 

[JuniorNA]

Ok I think I see what you mean - you're saying that if I'm at a mirror shine stage but have scratches - then I need to to down in grit and start over again And sand that out - then go back up in grit size - at least until there are no scratches and the metal is cloudy and Clean and then I go back up to 1000,1200

Because as of now my 1500 sand paper is making it all shiny but not removing the scratches and the mothers mag polish (which is supposed to remove a scratches is not )

 

[JuniorNA]

But also if there are no scratches and the finish is like a matte finish - then no sanding is necessary right ? I've been using micro fiber and mothers mag and I'm not seeing much difference

I guess I'm just trying to understand if its the polish that makes it a mirrored finish ? Or is it the sand paper going from 1200-1500-2000 that makes the finish like a polished mirror ?

 

[Chip_]

Because as of now my 1500 sand paper is making it all shiny but not removing the scratches.....

Yup, if you see deeper scratches with the 1500, then drop back, keep dropping back until the depth of all the pesky scratches match the depth of the scratches of the current grit size. When these match, then sand the whole thing with this current size grit. Once all the scratches are the same size, over the whole thing, then go to the next higher grit.

Now, this is all said without looking over your shoulder. As i said before you want to make sure that you don't have contamination, of a lower grit mixed with the current grit.

If it were me. I would drop back to 1000, sand the area of interest, if the scratches are deeper than the 1000 sand job, then I would drop back to 800, and keep dropping back until those pesky scratches match the current grit. Then I would sand the whole thing, and then advance my grits incrementally, until the final buffing stage.

Of course at some stage, those pesky scratches might be so deep, that after sanding, your tube may end up being as thin as aluminum foil - at that point - oh my!!!

 

[Chip_]

But also if there are no scratches and the finish is like a matte finish - then no sanding is necessary right ? I've been using micro fiber and mothers mag and I'm not seeing much difference

I guess I'm just trying to understand if its the polish that makes it a mirrored finish ? Or is it the sand paper going from 1200-1500-2000 that makes the finish like a polished mirror ?

HHmmmm. Actually it is all a sanding operation (even the buffing stage). Usually the buffing compounds I use are actually a grit size in a range from anywhere of 20,000 up to 60,000. And most likely so are the buffing compounds you are using. It's the scratch size that makes it look all shiny and mirror like.

So the polish gives you a mirror llike finish(super small scratches), but a 50,000 grit size isn't going to remove 800 grit size scratches. At least not anytime soon. I betcha if you put the thing on a machine at 50,000 grit size and let the machine sand for a week or 2, then it may eventually remove the 800 grit scratches.

 

[JuniorNA]

Wow thank to very much for all this info

So take a look at this



This started off as a matte finish / not brushed but not shiny - I hit it with 1500 grit and then used mothers mag and micro fiber and I'm nowhere near where I want to be - but since there are no scratches on this - like you said / I should order some 2000, 3000 grit sand paper and that will make it really shine and then use the mothers mag polish

 

[Chip_]

This started off as a matte finish / not brushed but not shiny - I hit it with 1500 grit and then used mothers mag and micro fiber and I'm nowhere near where I want to be - but since there are no scratches on this - like you said / I should order some 2000, 3000 grit sand paper and that will make it really shine and then use the mothers mag polish

First, make sure you are looking at your finish with a magnifier. This is how we inspect our grinding/sanding operations.
I have never use Mothers Mag, so I don't know what grit size it is.

Secondly, I can't tell what the finish looks like from the pictures. Actually the picture looks pretty good to me. Also it depends on what type of metal it is.

At this point, since this is metal, and you don't have or see any scratches, then I would say that you might want to try another buffing compound. With metals sometimes people actually jump from 500 right into buffing compounds and they are quite happy with it.

You could try Red Rouge, probably about 4,000 to 5,000 grit size (Manufacturers don't like to tell you their actual grit sizes).
You can buy this stuff at Sears. I have a little box of about 4 various compounds in a wax like bar sort of thing. Also the type of buffing material you use can make a difference on the metals. For soft metals like Brass, aluminum etc.. I like to use a leather pad, sometimes Red rouge works, other times, I have to use one of the others. This doesn't mean a muslim wheel won't work for you.

Here is a link you can sort of study --- Stellafane ATM: Grits, Polish & Pitch ---

Oh well, again good luck. ---

 

[fourtytwo]

Very good advice from Chip_
I would just add that you should just look upon polish as sandpaper in a liquid form.
That polish may actually be of a rougher grit then the finest sandpaper you have.
For some of the acrylic stuff I do, I use paper up to 12,000 grit but some of the polish I have is only 2,400 grit.
Clean, fresh polishing cloths are your friends. Make sure you remove all traces of the previous grits before you move on.

BTW, if you are finding it this hard to get a mirror finsh, how hard will it be to maintain it?

 

[JuniorNA]

Ok here is another sample -

This was a non mirror finish stainless steel - I connected the steel tank to a drill with a couple extended adapters while holding 1500 grit sand paper for a few minutes - I rinse and repeat several times and allow the steel to cool down - then after I clean it off and see no visible scratches - I put some flitz polish in microfiber and rotate it with a drill again and it gives me that mirror finish

But if the atty were not new and had scratches - I will take your advice and start matching grit size - get down to a scratch level and slowly go up in grit size until its a smooth finish - like the brass mod in the pic also

The brass mod was chrome plated and I hit it with 200 grit and now it's brushed brass but I want it shiny polished brass when done

 

[MrVapaar]

I have polished the center portion of my sigelei 19b, I started with 150 grit to get rid of the grooves on it. Then I went to 320, 400, 1000, 2000, 4000. If I stop at the 2k it looks real nice, but by going to the 4k it really makes it shine. Then I take a little mothers mag and aluminum polish and polish tbe heck out of it. I have polished all or part of 4 mods now, i do it all by hand and it takes quit awhile but it is well worth it. Makes my cheaper mods look just a bit nicer.

Sent from my SPH-L720 using Tapatalk 2