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soda blasting

5.3K views 19 replies 6 participants last post by  jdcz28  
#1 ·
Can you use your exsisting sand blasting equipment for soda blasting?
 
#2 ·
Soda

Depends on your blasting unit and type of soda you buy.
First of all I would like to warn you to stay away from the soda as some leave a film and unless special prepped paint tends to come off down the road. Not all sodas do this but a few.
A better option is glass beads if your not wanting to take off filler or surface rust.
 
#5 ·
Right

Older cars where metal is thicker not a worry but newer cars
do be carefull. My 55 chev I used 600 lbs of sand on the field junker and the 57 T-bird 300lbs but you won't hurt metal like that.
2000 honda--take an 80 grit da to it!
 
#6 ·
Soda blasting is a completely different blasting system. It takes ultra high pressure. Very expensive equipment. Wipe down with etch when finished.

Troy

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#7 ·
Speaking of Soda

I saw used one of the soda newer systems used a month ago.
Looked pretty neat. Its soda mixed with powered walnut shells.
It will spray out of a Pressured blaster (not a siphon) only. Harmless to the existing bodyfiller except thin top coat and the walnut sells are suppose to eliminate the soda reaction for paint adhesion problems. Could not get a cost figure as it was a demo.
But will when I go back in shop in month and let you know.
 
#9 ·
Well Kinda but not really!

You would think an 80 grit on a da and washing with wax and grease remover would solve the problem- but it don't!
Keep in mind not all sodas do this as there are many different kinds.
I was in a resto shop a month ago doing a Challenger for the 3rd time that the cusomer brought in soda blasted first time the 80 grit it and used an acid etch primer.
A few weeks ago I assigned one of my guys to get every soda out there and start testing to see where the problem is and how to solve it. Nothing like sand when your charging 60,000-100,000 to do a restoration., as this shop in Augusta would tell you! Well you really can't put in print what they would say!!
 
#10 ·
I had my 49 Diamond T soda blasted and there is a residue left which helps to protect the bare metal until it is finished.
The people that did the blasting told me to be sure and wash everything down with water because that will cut the left over soda and leave the bare metal.
He told me the only time he had anyone complain was because they did not wash with water first.
I haven't finished doing any painting yet so have no experince myself.
Hope this helps.
 
#11 ·
Water

Hey 41,
Thanks for advice, so far with what we have collected we have done around 20 panels cleaned each one different and than did an adhesion test. Funny you said water because the best one we did so far was cleaned with Waterborne Wax and grease remover. That had us scratching our heads so we just cleaned some with alcohol and some with alcohol mixed acetone
did not think about just water so we will try with plain water and a soap and water.
Thanks
Barry
 
#12 ·
Thanks Barry,
I know they told me water is what disolved soda where the solvents wouldn't take the coating off.
Seems different washing bare metal down with water before painting.
Also was told to then follow the directions of the paint supplier you were going to use for bare metal.
Have a great day.
 
#13 ·
The soda blasting did not take the rust off from my truck. It did a great job on the paint but not the rust. Did they do something wrong? I would stick with bead blasting or sand the next time I have something done that has thick metal.
Also I looked over the little blurb they gave me for finishing: It said to wash with hot soapy water and then a good rinse to remove the soda. Any white runs or spots are soda and need to be washed off before painting.
 
#14 ·
Hey 41,

I do believe thats the idea of soda blasting to leave body filler and surface rust so you can see what you have. I know thats why we use certain media blast materials. Not 100 % sure on the soda.

For your info so far the panel that we washed with soap and water than DA'd with 80 grit than washed with wax and grease remover has perfect adhesion with epoxy. We tested at 4 days and 5 days. Really your suppose to wait 7 days as thats when you get maximum adhesion.

It also did real good on the chip test on the 5th day, so I guess thats the answer to cleaning the metal??
I'm still not real comfortable with it with all the problems I've seen in past.
 
#15 · (Edited)
I own a soda blasting business of 5 years and joined the board today to post comments and answers from my experience.

Soda blasting can only be done with soda blasting equipment for true performance. Sure, you can stick baking soda into a sand blaster or plastic media blaster but, to complete a full car body would be very expensive. Baking soda is a one pass media that cannot be re-used like sand or plastic media. If you cannot control the flow, the excessive waste will empty your pockets buying the media.

Baking soda does remove bondo but, will not remove rust.

It also must be rinsed thoroughly with water, yes I did say (water) in order to remove the soda completely from what you blasted. After rinsing you want to towel dry all areas to prevent thick baking soda residue runs. These runs can also be removed with a combination of vinegar and warm water if it has air dried.

After this process is done, soda leaves a invisible layer that acts as a buffer to the metal. If stored in a dry area with no moisture or humidity, the metal can go as long as 6 months before flash rust appears. That means no immediate need for primer.

Etching primer is a no no, only use epoxy primer to the bare metal first. All areas must be cleaned with wax & grease remover before primer as normal.

I have never had an unhappy customer or any problems with paint coming off the car.

To comment on the rusted areas, soda removes all surface rust down to the substrate. It will leave the areas a dark black color. What works best for me is a hand-held sandblasting gun filled with #5 sugar sand. Go over all black areas until the metal turns white. These areas also have to be primed immediately.

No need to remove or protect glass or chrome from the car either, baking soda is non abrasive and does not generate heat.

I hope this info has been some help to many concerns about this process.
 
#16 ·
Jdcz28,

Thanks for the education, this has been a very confusing issue to a lot of restorers.

You can see what testing i tried to do in previous posts but you stated just rinse with water?

Warm soapy water is not needed? What about the vinegar with the first washing would that be an additional benefit?
Barry
 
#17 ·
BarryK,

Glad I could help.

Yes, plain water is all I've ever used. If soda is built up in tight areas rinse with a pressure washer. Adding vinegar to the first washing really has no benefit. If you towel dry after you rinse, you will see the difference. The only time I have used vinegar is on thick runs that have air dried. This basically breaks down the build up. Adding soap will only break down the buffer agent in the soda that help protects the metal.


John
 
#18 ·
jdcz28

Thanks for the info. Should you prime the metal as soon as you wash it?
When I had my truck soda blasted they didn't tell me the length of protection was about 6 months so I have some rust areas appearing.
I have painted a few pieces with Air Color water based paint and have not had any problems yet.
Thanks again.
derald
 
#19 ·
41,
Anytime you wash metal it should be dried right away and not a bad idea to take a blower to it but let it set at least 30 minutes before coating to be sure it is totally dry.
Also at this point I would run over the metal real quick with a DA and 80 grit just to make sure all film is gone.
 
#20 ·
Derald,

There should be no reason to prime immediately if the body is kept dry. If your are in and area with high humidity or the body is subject to any type of moisture it will flash rust earlier.

Here is an example: Say you had a hood blasted and it was properly rinsed, then towel dried. Then you put it in your garage. A month later you decide to open your garage door and leave it open all day and the humidity is high. The moisture in the air will land on the metal and generate flash rusting.

If the hood was kept in a climate controlled area such as room in your house or dry storage not subject to any type of weather, I've personally had pieces go longer than a year without any flash rust appearing before I decided to prime.

Also be aware that just because it's sunny outside, there is still humidity in the air. Such as morning dew on the ground. As the suns heat drys the ground the moisture rises as it evaporates.

I know people can't stick a car in their living room, don't get me wrong. But, if you pay attention to the moisture issues 6 months should be a minimum.

Did you use epoxy primer to the bare metal before your paint? If you did, you should be fine.

John