Soda Blaster

[Mith]

I thought someone here may be interesting in seeing how I built a soda blaster gun. It was very inexpensive to fabricate. All I had to buy was a 1/4" compression tee. I already had the 1/4" soft copper tubing and the 3/16" copper tubing and the 5/16" steel tubing. Here is a picture of the completed blaster.
http://i1027.photobucket.com/albums/y335/Mithrandier/SodaBlaster.jpg

This next picture shows the blaster disassembled so you can see how the 3/16" tubing was ground so it tapers to a tip. It is then inserted into the 1/4" tubing so it protrudes about 0.460". This is the only critical dimension. This is because it needs to be blowing the high pressure air directly into the outlet side of the tee or else it will not create a vacuum on the flexible tubing that will draw the soda.

The last detail is the outlet side. I had to use 5/16" steel tubing because the outlet had to not create much backpressure or it would blow air out the soda draw tube. By using 5/16" rather than 1/4" it allowed it to work great! I used a piece of 5/16" steel line that I flared. I drilled out the compression nut to accept the O.D. of the tubing and ground the outside of the flare on my bench grinder until the nut would pass over the flare.

I find that this blaster works far better than the method where you slit a piece of flex tubing and poke the end of the blaster into the slit.

 

[mighty13d]

Yep ... I've seen your home-built, and a few others, and appreciate the reminder. However, I have something larger in mind.

I just acquired a pretty sturdy "snap together" Rubbermaid cabinet that is similar in size to a very tall standalone "coat closet." While I was originally going to use it as a storage unit it just occurred to me that it would make an awesome blast cabinet! I want to be able to put large, long items in it (like mounted aluminum wheels) and go to town!

The biggest challenge will be to seal up all the seams where the full length swinging doors close, but I figure a combination of adhesive foam and silicone sealant ought to do a sufficient job of keeping the mess contained. I will also have to reinforce the structural rigidity of the unit, because one or more of the shelves (that I have to take out) normally act as structural parts of the cabinet. I already have plexiglass sheeting to use as a window, so it's now just a matter of picking up the other accessories to finish the job and start constructing! My intention is to add a filter and ductwork leading to my shop vac, so as to keep from blowing the cabinet up, hehe! The shop vac already has two filters built into it (replaceable, of course) so I should be good to go on that front.

Regards,

I used my shop vac with a port I cut in the top of the back. I used screen right there to keep the sand in but pull out the dust. Works great to keep dust down. I just used normal weather stripping on the top lip of the tote and it keeps a pretty good seal up there.

Whats the air pressure and brown stuff. And how dont you make it blow up like a balloon?

Even before I used my shop vac, I had no pressure issues. The sleeves I have taped to it do not seal. They are just flannel sleeves and only there to keep the sand and dust inside. They don't keep any air pressure in. I basically used what I had on hand so it cost me nothing.

 

[anthonygs1000]

soda blasting

soda blasting

I bought a small blast cabinet from harbor fright and dedicated it to soda only. I bought the soda from sams club in bulk. I use a small pancake compressor and it operates best with low low pressure. I hooked up a shop vac to be able to see. the job this thing does on aluminum is incredible. I have also tried the homemade method building the gun and the work but what a MESS

ant

 

[wirelessguy]

Soda blasting / mixed results.

Soda blasting / mixed results.

After reading this thread on soda blasting and seeing the article from the link I'd thought I'd give it a try on my own project.

The results were sort of mixed (and I'm open to suggestions for improving my technique). While the shots of the Porsche carbs wee cool I haven't had great success in stripping paint using baking soda.

I started off by getting the cheap air gun from Harbor Freight (w/ 7/16 hose from HD) and tried some household baking soda it took a good amount of (spray can) paint off of my stator cover but I had to keep the PSI on the compressor pretty high.

I returned to Harbor Freight for the Armex with my discount coupon. I also found a broken open bag which they sold me for $15 and the blasting backpack for $15 (with gun and all).

Quick impressions:
The blasting gun & backpack is only slightly better than the el-cheapo air gun but the container IS somewhat convenient for me. Sadly neither of these setups are working out too well on paint stripping. I'm up real close, using a 45 deg angle and blasting is best at about 120PSI (sadly my compressor auto shut off is broke so I've got to keep playing the spray and wait game wit the unit in full on mode. :-(

I'll include some resulting here but I will say that I think that both a higher PSI and smaller nozzle jet opening would have been helpful here. I do think I could re-use the soda for stripping paint if I were blasting within a cabinet but I'm doing it out on the driveway with full face gear and hat on.

I find that rotating b/w using blasting and hand sanding or buffing with air sander produces good results.

For reference, I'd say I've been through close to 15-16lbs of blast so far and I haven't really gotten to the second side of this center stand just yet. While it beats sanding by hand it's not as efficient as I'd have hoped.

*** For anyone following along here are my suggestions...
Soda blasting is not known to remove varnishing on boats or other grease like materials. I did have some crudy grease I needed to scrape off with a blade before I even began.

1 . Scrub part clean by hand best as possible
2. Bathe part in paint thinner if possible to loosen paint up. (Rust remover might be good idea too. )
3. Rinse and allow to dry
4. Attempt Soda blasting then some hand sanding, repeat until finished

 

[SVSooke]

Soda is not really good for rust.More for delicate things like carbs and aluminum corrosion.Ground walnut shell are supposed to be better for rust.

 

[mighty13d]

Soda is not really good for rust.More for delicate things like carbs and aluminum corrosion.Ground walnut shell are supposed to be better for rust.

+1 Soda is VERY VERY mild. it's not made for paint removal. Let me see if I can get a chart.... Ok I had to make one. I found one on a website and had to print screen it and then paste two sections together. lol well not like anyone care about that part. Anyway, here it is: