need abrasive ideas

[DogBunny]

https://www.xs650.com/threads/video-of-my-potters-wheel-tank-tumbler-cleaner.62917/
Link to my tank tumbling cleaning thread above, wherein I put abrasive materials inside a tank and tumble it in order to clean the inside.
I have used Harbor Freight resin media and their ceramic media. Both work. Will clean a tank enough that it is perfectly suitable to be put into use.
However, I would like to make a tank that is SPOTLESS.

The problem is that both of those HF medias cannot get into the tiny pits. This pic is a HUGE blow-up, it makes it look worse than it really is, but nontheless, the surface gets cleaned very well, but the pits hold their rust. The media just can't get in there. I've tried adding Play Sand to the mix, but it doesn't help -- tumbling is not like blasting sand at 90 PSI.
The next thing I want to try is short drywall screws. The problem with them is they only have a single sharp point.

What would be ideal would be something like jacks, but with all points, and all the points being very sharp.
I know this is a long shot, but can anyone think of anything that exists like what I want?
If not, my next try will be with the drywall screws.

 

[WideAWAKE]

What are you using for a solution in the tank, if any?

When I was working in aerospace we would use a slurry to do internal tumbles.

Maybe throw some evaporust in the mix.

We would use an acid which works fantastic but then you gotta neutralize it.

 

[DogBunny]

Those are great ideas. However, the big attraction with tumbling as I do it, is no solutions. Less mess, less fuss. But far more important, is no flash rust.
I've tried adding oil and kerosene mixture immediately after flushing a tank that has been solution-cleaned, but now you're talking an additional solution and more mess, and you STILL get some flash rust.
Dry tumbling is really simple and easy. Result are perfectly usable. I'm just a bit obsessed with getting the rust out of those tiny pits.

 

[WideAWAKE]

Yeah a clean job is nice.

If there is in fact anything out there that would clean those micro pits it would have to be an abrasive that is smaller than the pits themself

Maybe throw in a couple big scoops of heavy grit baking soda? Works great for that sort of a thing out of a blast cabinet but that’s with air pressure.

Or here is a possible idea.

Take some of your current media, stick it in a bag and smash it to a fine powder. Throw that in the mix???

 

[Dom]

Phosphoric acid, got my tank spotless

 

[OHRider]

What are you using for a solution in the tank, if any?

When I was working in aerospace we would use a slurry to do internal tumbles.

Maybe throw some evaporust in the mix.

We would use an acid which works fantastic but then you gotta neutralize it.

I think evaporust would be great after the tumble.

 

[OHRider]

What are you using for the tumbler? Photo please

 

[DogBunny]

Yeah a clean job is nice.

If there is in fact anything out there that would clean those micro pits it would have to be an abrasive that is smaller than the pits themself

Maybe throw in a couple big scoops of heavy grit baking soda? Works great for that sort of a thing out of a blast cabinet but that’s with air pressure.

Or here is a possible idea.

Take some of your current media, stick it in a bag and smash it to a fine powder. Throw that in the mix???

Yeah, I really think I'm asking for the impossible here.
I've tried baking soda (actually, I used Borax). Same problem as with the Play Sand, tumbling it isn't the same as blasting with it.
However, when tumbling, I've found that a couple of tablespoons of the Borax are very beneficial. They keep all of the rust and varnish particulates that get abraded from the tank "cleaner".

Phosphoric acid, got my tank spotless

I've used all of the usual acid suspects. Phosphoric, Muriatic, vinegar, even Sulfuric acid. They all get tanks spotless. And they all get flash rust afterwards.

I think evaporust would be great after the tumble.

The whole point of tumbling is that there are no solutions involved.

What are you using for the tumbler? Photo please

Thread is here:
https://www.xs650.com/threads/video-of-my-potters-wheel-tank-tumbler-cleaner.62917/
Video is here:

 

[Dom]

That's because you rinsed it out with water I'd imagine.

 

[DogBunny]

That's because you rinsed it out with water I'd imagine.

What do you rinse yours with?

 

[RC4MAN]

We use something at work, in the tumbler, the hot water washer etc. that prevents rust for a reasonable period. I'll find out what it is, and if it's reasonably available, we buy it in 50 gallon drums.
Clean all the aftermarket OTR truck engine parts we make, oil and water pumps, heads, exhaust manifolds etc.
It allows time for packaging, shelf storage and shipping to customers without rusting.

 

[bosco659]

I was under the impression that surfaces treated with Evaporust would not experience flash rust because the surface becomes chelated. I know it the past I’ve used it to remove fairly heavy rust on cast iron parts and years master there was not rust with the parts sitting on a shelf.

 

[DogBunny]

We use something at work, in the tumbler, the hot water washer etc. that prevents rust for a reasonable period. I'll find out what it is, and if it's reasonably available, we buy it in 50 gallon drums.
Clean all the aftermarket OTR truck engine parts we make, oil and water pumps, heads, exhaust manifolds etc.
It allows time for packaging, shelf storage and shipping to customers without rusting.

Yes, I'd like to know what you use.

I was under the impression that surfaces treated with Evaporust would not experience flash rust because the surface becomes chelated. I know it the past I’ve used it to remove fairly heavy rust on cast iron parts and years master there was not rust with the parts sitting on a shelf.

I've never used Evaporust. I just Googled it. It is NOT an acid. And yes, although I don't understand the science explanation, "selective chelation" is mentioned. In any case, if you say it doesn't rust afterwards, I believe you.

 

[WideAWAKE]

Evaporust is good to go after use, that is why I suggested it.

 

[jpdevol]

Might be this stuff - I use it in the vapor blaster - taint cheap

 

[DogBunny]

Might be this stuff - I use it in the vapor blaster - taint cheap
View attachment 236556

That's an interesting product that I never heard of. I looked at the MSDS in an effort to figure out why it works. I still don't know, but I'll say that it has some pretty nasty-sounding chemicals in it. The MSDS says no respirator required, but I would.
Again, interesting product, but not sure how effectively you could spray down the inside of a tank.

Not to sound whiney, but with all of these solution suggestions, I have to return to the advantage of tumbling: it is DRY and relatively quick, easy, and clean. Which makes it ideal for use on tanks that have good paint jobs.

 

[jpdevol]

advantage of tumbling: it is DRY and relatively quick, easy, and clean

I'm with ya on the dry tumbling. Flash rust is the bane of a lot of various prep methods that require some rinse. The "salt remover" prevents the rust when using any water-based process - be it spraying or immersion. It's pricey, but the mix is ~ 50:1. I haven't read the data sheet though

 

[46th Georgia]

Might be this stuff - I use it in the vapor blaster - taint cheap
View attachment 236556

Had a car soda blasted. That's what he used. I was there when it was done, no fumes, no respirator used. Have a piece of "test Mustang" laying around for over a year in the humid Okefenokee area. Still not a speck of flash rust. Good stuff.

 

[OHRider]

What do you rinse yours with?

Give it a 5 minute soak with baking soda water, a table spoon of baking soda per gal. It will stop the flash rust problem with a acid soak.

 

[mrtwowheel]

I haven't read this whole thread..........I used roofing nails, about three pounds worth and some WD-40. I wrapped the tank in blankets and tumbled it in a clothes dryer packed with more blankets. This worked better than the acids and electro that I used in the past.