Tumbled bottles turning translucent gray

[azokie]

Hi -

Hoping somebody out there can help me out with this problem. I have been tumbling soda bottles for about two years. About six months ago, I started having a problem with the bottles coming out with a translucent gray coating that cannot be scrubbed off. Apparently the bottle is heating up and the tumbling mixture anneals to the surface of the bottle both inside and out. This only happens when using the "aluminum oxide" polishing compound. It has never happened using the 1200 grit silicone cutter. It seems to happen randomly. I can tumble three bottles at one time, and one bottle may come out with the coating and the other two will be fine. I talked with the tumbler manufacturer and he was familiar with this result, however I don't think his explanation of the cause is correct in my case. He thought it might be the result of a "dry run" (not enough water). This is not the case, I can overfill the canister and still end up with this result. Why didn't this happen in the first 18 months? Why is it happening now? Could it be dirty copper? By the way I'm in Phoenix, AZ and the outside temperature can be brutal - could that possibly have an effect? Has anybody out there ever experienced this problem? If so do you have any suggestions? Any help would be greatly appreciated!

Note: Incidentally the gray film can be tumbled off and the bottle looks fine, that is if it doesn't happen again. This is driving me "nuts"....Please help.

Sincerely -
Brent

 

[tazmainiendigger]

Hi Brent, I tumble and have seen this... I think different compositions in glass might have something to do with it.... Have you ever noticed how sometimes the "suds" in the tumbling froth has different colors?? Sometimes a light yellow other times black and inky... I usually wash my bottles out of the tumbler in plain water and then fill them with approx. 25% ammonia, I then scrub the inside with a brush/swab... then pour out the bottle contents on a sponge and rub down the outside... Try it you might be surprized... Taz

 

[azokie]

Hi -

Thanks for the information. I have heard from a couple other people that the gray film can be cleaned off with some different solvents.

I'm still interested in finding out why this happens. I have noticed some different foam coloration, but again I tumble only soda bottles, so the glass composition does not vary widely.

Any other thoughts or ideas are welcome.

Thanks -
Brent

 

[thturk]

I don't know if Arizona has bentonite. But Wyoming has a lot and it has high concentrations of aluminum. If the bottles you are cleaning have a bentonite residue it could be binding with the aluminum oxide. Bentonite resists liquids (water) and with heat could harden on to the glass. Bentonite only succumbs to scrubbing with a brush. We've had our black angus cows fall into bentonite blow holes and when removed have spent almost a year looking like a Charlois. (A white/gray breed of cow.) It's an insidious type of volcanic ash/dirt. I personally hate it. [X(]

Trish

 

[Bottle tumbler]

you may be using to much oxide or cutter if they come out like a gray bottle. I use muratic acid in lots of water and dawn soap to clean mine,

I have cut back on my polish to 3/4 tsp and it has help on most of my bottles

rick

 

[azokie]

Hi -

Thanks for the tips. Right now, I am using about 3/4 tsp. inside the bottle and 1-1/2 tsp. on the outside for a typical soda bottle. Does that sound about right?

Hey "Bottle Tumbler" does copper ever get too "old"? Should you keep the copper you use for polishing and the copper for cutting seperated?

Does the speed (RPM) make a big difference? Can you tumble a bottle too fast? How many RPM's do you recommend for a typical soda bottle?

Any help would be much appreciated.

Sincerely -
Brent

 

[Bottleman]

Hello, the amount of oxide you are using for your bottles sounds about right although I use a little less. Copper can get to old and by this I mean the edges get rounded and it will take longer to polish a bottle but will not affect the appearance. I have been using the same copper shot for the last year and a half and I have had no problems with it yet. The speed does make a big difference. You should tumble square or oval bottles around 30-40 RPM’s and round ones around 60 RPM’s. I like to tumble my sodas at 60 but sometimes I think that is a little fast so I will drop it down to 50. DO NOT cut and polish bottles with the same copper. No matter how long you wash the copper, the oxide is still embedded in the copper and will come out on bottles you don’t want to but cut.

Hope I answered your question, Tom

 

[azokie]

Thanks Bottleman for the good tips. After a tumble, do you just spray the copper down good with hot water or should I use something else to clean the copper?

Keep the tips coming, I'm finally getting some answers here!

Thanks -
Brent

 

[Bottleman]

I use a regular kitchen screen and dump the copper in there and run water over it until the water coming out the bottom is clear. Do not add soap because this will stick to the copper and cause foam in your tube which may pop the stopples out. Did you try some of the suggestions above to get the gray film off of your bottles and did they work?

~~Tom

 

[azokie]

I have not tumbled any bottles since posting my querry. Will probably start tumbling some bottles this weekend. I'll cut down on the amount of compound and double check the RPM. I'm going to order new copper just for polishing too.

I'm still not sure why the bottles started turning trans. gray, maybe it's a combination of all the above.

Thanks for the help. Any other advice is welcome...

Sincerely -
Brent