Restoring '46 Brunswick Anniversary - Castings Concern

The 60 + year old anodized aluminum pocket castings were taken to an alumunim treatment facility near where I work. I was expecting a consistent satin sheen with a hardcoating but got a soft 'primer-gray' color instead. There were concerns about the porosity of the old aluminum resulting in this. They suggested a powder coat like paint process to follow. I'm wondering if the gray color would result if the castings were not de-anodized first. I had mentioned this before handing them over. The reason typical off-the-shelf aluminum polish (like from Mother's used for mag wheel polishing) doesn't work on these old pocket castings is because they are anodized. So, logic tells me if the castings had been de-anodized first, this might not have happened.

Can anyone tell me what other options I might have? I realize it could take someone with a chemical engineering background to answer but hopefully someone will know. I mean, can these still be chromed perhaps?

@ chevybob... we gotta talk... this is what I'm dealing with. I've been told now that chroming them will make them nice and shiny, but will also show all the imperfections due to the porosity of old castings. I guess the aluminum wasn't so pure in the 40's ???

pocket surround castings

@ bigkahuna: As far as I know, the castings were dipped into "Type-III Hardcoat/Class I Natural" anodizing solution. (Exceedingly nice work on your majorly detailed restoration/documentation effort by the way... just got done reading thru ALL of it)

@matteroner: I will be scraping the inside of one of these castings to see how deep I have to go to get back to what looks like aluminum. If I proceed with a DIY polishing effort, that will hint at what grit to start at. I mean, I can polish agates, gems and minerals and alumunim is considerably softer than some of those I work with in my lapidary hobby, so this shouldn't be too difficult conceptually. I don't own a bench grinder though so I can't attach convenient polishing/sanding wheels to it. That might have to change.
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If I get these powdercoated, I hope there's a nice shiny silver (untextured) color available. I've been searching the awesome forums here at AZBilliards trying to find as many photos of powdercoated pockets as I can. Can't really use the GC copper pics to judge by. I don't know exactly what state my pockets are currently in... that is, they "appear" to be ready for some kind of coating because it looks like a smooth, flatter than flat gray color (slightly beige/olive too)... completely sheen free at present. I'm going to continue researching what "chrome/sandblast" looks like before deciding on powdercoating because i've been quoted $243.50 to do all 10 pieces that way (or $487 for chrome that might not turn out the way I hope.)

centennial polishing

thanks for those photos! wow... you did a great job on those! You are a patient individual. I just wish I had seen your process and photos before I had my castings dipped. I'm reluctant to attempt a DIY polish because they look so different after the recent anodizing compared to how they looked before that.

castings continued...

@chevybob20 or anyone curious... I'm encouraged to give it a go (DIY polishing). Here's why. One thing I hadn't mentioned is that when my newly anodized castings were returned to me, one of the 45 degree angle fastening brackets had come loose from its weld (a clean break at the weld joint on the back of one of the side-pocket castings) during the dip, or, someone dropped it just right. In any case, I can easily refasten it later, but the point of me mentioning it is because it became a guinea pig for finishing. I let that small bracket (I'll post pics of it tomorrow... don't have my good camera with me) sit in a dish of Drano (foam kind) for about 20 minutes. It came out looking a bit duller than the anodized surfaces.

First thing I did was use a small wire scrubber attached to my Dremel mounted in a drill press accessory. It produced the pure aluminum (silver) appearance I was hoping for, but not smooth of course.

I then proceeded to use an 80 grit aluminum-silicate based sandpaper attached to a Rotozip tool to smooth that same flat surface and it removed almost all of the deeper imperfections. I only had 220 grit besides the 80 in the same sandpaper type and it did an amazing job. I can only expect better and better results going with a proper series of grits, and finishing with 0000 steel wool.

After each of the three surfaces were done this way, I tried the Dremel polish paste on one face, and though the surface was smoother, it did not have significant more luster. I tried Mother's Aluminum Polish paste and it produced better results. Polishing wheels on the dremel were used in both cases. Again, going thru the proper grit sequence should result in excellent result. I even have cerium oxide for my stone polishing, and might experiment with it on the aluminum. Wishing I had tin oxide instead, but cerium I have plenty of.

I'll post photos of the bracket tomorrow, but my next step is to get more Drano (but I think I'll just use the regular stuff, no gel, or foam) and dilute as little as possible to de-anodize the larger pieces, hopefully two at a time or more. I wonder how long I can leave the pieces in there... I mean, the longer the better??? I don't think 15-20 min is long enough to soak thru those old castings, especially for the pieces that are much larger than that small angle bracket.

castings continued and a few other pics

I'm posting a few photos I took this morning. Hopefully they will show a clear difference between the treated aluminum described in my previous post and my sanding efforts.

circa '46 Anniversary serial number and nameplate

Photo of nameplate and inside of rail apron (serial number). I'm hoping someone can tell me a more precise year this table was born. "BB/3107 79560 9 FT MOD D-C".

The third photo shows one of the small skirts that attaches next to the ball catch. You'll see it is missing the lower strip of wood. The missing pieces will need to be crafted or I can get new ones from Ken at Classic Billiards.

more progress on the castings

@oregonmeds... that last tip could come in handy... I would not have thought of that at all. thanks for the post!

@ all:
I used about 6 tablespoons of crystal Drano mixed with enough water to submerge the two side pocket castings. I had them on wires for frequent inspection. As advertised, Drano makes quick work in its de-anodizing chemical reaction thanks to the sodium hydroxide (which is found in other common household agents). About 20 min of soaking, some agitating here and there and ta-da... they came out charcoal gray. I then took a wire wheel accessory attached to my Dewalt elec drill, and proceeded to speedily clean the surface, though it did leave brush marks, but at least I was getting somewhere... a nice consistent silvery color with low sheen. Next I went to a 120 grit 5" sandpaper attached to a padded backing/drill accessory. It did a remarkable job on its own, but I begrudgingly stepped up to 220, then leaped to 600 alum oxide wet/dry paper, just to see its effect. Somewhere in todays hardware store browsing, I forgot to get 400 grit. I then applied Mother's alum mag polish, and did a quick terry cloth buff by hand to get an idea of how these ALL are going to look.

I remain highly encouraged by the results thus far. The challenge I'm having is the drill attachment being 5" diameter. Though the grit is stuck to a padded backing, I can't get it to flex over a broader area on the curved surfaces. I think what I need is simply sponge/padded blocks of sandpaper, but hard to find them in all the needed grits. I'll post pics of the continued progress tomorrow.

castings continued...stark contrasts and streaks

For those that had to scroll to see the enormous photos from yesterday...apologies. I've resized these new ones to a good proportion (from 8x12 to 5x7).

In each of the following photos, there is a reference image showing one casting that has not been de-anodized. Some people might actually like the way that looks as its relatively smooth, and consistent in color, but this is not the way Anni's or Centennials were intended to look.

In the first photo, the curved portion is not sanded, but shows what a wire brush on a drill will do. De-anodizing and brushing will make the castings look like metal again.

In the second photo, the curved portion is streaky due to the ridgidity of the power tool attachment. It is quite apparent it does not flex enough so I need sponge-type blocks for even pressure on the bends.

In the third photo, just highlighting the stark contrast from not a tremendous amount of effort.

Each photo where there is shine, was sanded using 120, 220, then 600 and includes a single dose of Mother's Aluminum Mag polish, which made the surface smoother to the touch, but did not signifianctly enhance overall sheen. I did not have 400 grit (error noted late last night). I do have 1500 and will give it a test run, but due to the natural imperfections of the old porous castings, I don't know if it's worth doing. I figure the results will end up looking just like the chrome shop told me... nice and shiny but with all the imperfections jumping out at you. For a perfect sheen, I'd have to sand every scratch and pit out. At 600 I'm getting very desirable results, and I haven't even used the buffing wheel yet. The castings still look like they're from the 1940's but with no oxidation.