Auto body repair & detailing: Sandblasting


Question
QUESTION: I have approx 2000lbs of steel barbell weight plates. I bought them all used so they are 5 different colors and have lots of rust on them. I have free access to a sandblaster so that is how I want to clean them.

I like the look of sandblasted steel so if I could leave them sandblasted I would. The weights will be kept inside in my basement where I will have a dehumidifier on in the more humid months of the year. In that type of environment, will they still rust if not painted or protected and if they will how bad will the rust be. I'm ok with some flash rust I just don't want the kind that is there in flakes.

Also if I do sandblast them and descide later on that I want to paint them is there a paint that I could use that could go over the rust and still adhere well to the metal.

I don't really want to paint them for 2 reasons.

1-I like the look of sand balsted steel and I think that would be a unique look for my weights and I would be finished as soon as I'm done sandblasting them.

2-Because they are weights the paint will chip no matter how good it is.

ANSWER: Hi again Ian!....I talked to you on August 14th in regards to your question. At that time, you did not have access to a sandblaster. Great to hear you have access to one now. Once the plates are sandblasted, and even though you have a dehumidifier, flash rusting will occur regardless, being that they are metal, exposed to oxygen, and also from handling them. (
The moisture from your hands will start the flash rusting right away ) My advice, is once you have sandblasted them completely, is to spray them with a Clear Coat as soon as possible. This will seal out all elements, eliminate flash rusting, and will give you the look of sandblasted steel. As you have mentioned, if down the road you decide to paint them, all that needs to be done then, is to scuff them up with a red Scotch Brite pad, and paint them whatever color you decide. Hope this helps you out again...If you have any other questions or concerns, please feel free to drop me another line. Thanks...Dave

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QUESTION: Sounds good. I didn't realize it was you that I asked. I guess I didn't need to fully explain myself.

Thank you for your patience.

Have you ever heard of or used a product called Corroseal? Apparently it converts rust to a black surface they call Magnatite. Hope I got that right!  Anyway from what the add says the rust will be black and it will prevent further rust. I was thinking about sandblasting them, using them for a while till they are covered in flas rust and when it gets to be too much, use the Corroseal. I just don't want to make a bigger mess than I have and have to redo them.

If I sandblast and  paint them can I use a paint like Tremclad?
Is a primer coat mandatory?
Can I use a brush?

Or if I use a "rust paint" would it actually help to have some flash rust?

I just want to make sure I get this right the first tome so please bear with me!

ANSWER: Hi Ian!....No problem at all! Ask as many questions as you like, as this is what I am here for. In regards to the product called Corroseal, I have honestly never heard of it. As for Tremclad, that is definitely an option. Your best bet if you wish to try Tremclad, would be to check out the instructions on the can, and see if a primer is recommended, or if you can simply spray over the flash rusting. In my opinion, I would recommend a product called "Por 15". ( I have included the link below ) It is a 3 stage process, and from all accounts, and people that I have talked too, they all have had excellent results. Por 15 actually recommends that some surface rust exists for proper adhesion. They also recommend it be applied with a brush, and it apparently flows out as if it was sprayed. Hope this helps you out again. Drop me a line and let me know how you made out. Thanks for your question....Dave

Here is the link:   www.por15.com

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QUESTION: One more idea. If I sandblast them, lay them all out on the floor and spray them with silicone spray (or something else scent free that would dry non greasy) as always open to suggestions!

Anyway if I would give them a good heavy spray, let it sit for a while, then wipe off the excess, would that help.

Answer
Hi Ian!....If you think that possibly down the road you would like to paint the plates, definitely DO NOT use any type of silicone spray before hand. Silicone is a painter's worst nightmare. It will soak into the pits of the sandblasted material, be next to impossible to remove, and will cause a condition called " Fish Eyes ". Since you prefer the look of the sandblasted steel, and possibly paint them down the road, I would sandblast them, and as soon as possible, simply apply a coat of " Clear Coat " on them. It is available in a spray can, will soak into the pits, and seal out any contamination that would occur from handling them. When you decide to paint them, all that needs to be done, is to scuff them up with a red " Scotchbright " pad, wipe them down with a wax and grease remover, and paint...Thanks again for your question...Have a great weekend....Dave