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Last weekend, I purchased a blast cabinet from Harbor Freight Tools, it was on sale for $79.99. I have it in operation, and I’m having a blast with it (literally). As discussed previously on Trainorders.com, I chose to use baking soda for my blast media. The first thing I learned is that blasting uses a tremendous amount of air volume, and my compressor was running continuously and still not keeping up. My first improvement to the blast cabinet was the addition of an internal light fixture as it was very dark. After a trial blasting session, I found myself working in a cloud of dust and quickly connected a shop vac to the vacuum port on the back of the cabinet. My first victim was an old Atlas RS3 hood, which are tough to strip. The paint came off clean, with a couple of passes. It’s amazing how it takes the paint off effortlessly, but doesn’t harm the plastic. Since our garage and I were already a mess, I decided to strip my Kato SD40, which I custom painted about 12 years ago with Scale Coat paint (I never liked the shade of yellow that resulted). So far, I’m pleased with the results, but still need to make improvements. As I already mentioned, I need a larger compressor and I need to find a way to keep the baking soda moving to the bottom of the hopper while blasting. I have attached a picture of the cabinet and a couple of the shells I stripped. I never liked using chemical paint strippers because they are so messy and labor intensive. The blast cabinet is an alternative, but still messy. In the future, I’d like to try using the blast cabinet for weathering, to simulate fading paint and lettering.

Dennis

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What is the compacity of your air compressor?

Dave Potter

David Potter
Other, CA

Good info, didn't know they were on sale. Didn't know about the baking soda trick, that stuff always clogs up.

What pressure do you use and are the edges of the models dulled at all because of the blasting? Thanks.

My compressor is a 1960's vintage single cylinder type. It has a 12-gallon tank and a 1/2 HP motor. It's rated for 110 PSI. I set the regulator for 50 PSI when blasting.

I haven't had any trouble with the baking soda clogging, it just doesn't like to slide down the hopper to the tube that feeds the blaster. I had to frequently shake the cabinet to keep blasting.

I can't see any damage or loss of detail to the shells I've blasted.

Dennis

The keys to keeping a good flow are a water trap on your air line and a vibrator on the hopper. At work, we have a little motor with an eccentric weight on the end. That thing "thumps" the hopper and keeps all the blast medium settled.

Z

Has anyone tried the crushed walnut shells for paint removal? I have the equipment around that I use for tool cleaning and graffiti removal, including a newer gun that can work with the walnut shells. I have been considering getting one of the Harbor Freight blast cabinets for myself later this year and would prefer to use something besides the baking soda or glass beads. Thank you.

GP30

I have rigged up a cabinet from bits of things found in your local Home Depot sort of place. It has worked fine for me but I find my biggest problem with blasting is my Cheapie Badger Grit blaster. I find the grit does not flow continuously. Can anyone recommend a fix or a good alternate?

Rick in Oz

Some brands of ballast are made from ground-up 'nut' shells, never noticed which kind though. You'll notice some of the ballast 'floats' in water while some of them just sink.

GP30 Wrote:
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> Has anyone tried the crushed walnut shells for
> paint removal?

what arr the inside dimensions of the blast cabinet?

When looking at the specs on an air compressor, its the CFM that is key, NOT the psi or hp of the motor. Air tools have a cfm (cubic feet/minute) rating and the compressor needs to exceed that to make the tool work properly. The blast cabinet should have that rating somewhere. Check it before you buy a new compressor.

i have had 1 of those for years. http://highhood.com/images/models/engines/atsf%20108%20c.jpg since i used to have to pay some one 20.00 per unit + s-h to strip my kato;s it was well worth the 79.99. just compleated a new table for it to sit on. the old table was a plywood sheet on 2 large boxes. http://highhood.com/images/models/engines/atsf%20%20108%20%20b.jpg shows the air compressor which i run at 30 psi for blasting and 20 for painting

If you want to try walnut shells, go to a Petsmart/Petco and check out the bedding materials for birds or reptiles. You might be quite surprised at the price for ground walnut shells sold for pets to poop on and the price for walnut shells for blast media. Same stuff.

That said, the walnut shell media is a little large for the Badger blaster, but is fine for larger commercial blast guns.

Excellent! Thank you for the answers on the walnut shells. I have experience with specialized work in sealed cabinet blasting as one of my second jobs for awhile was working removing electroplating residue from the contacts of very expensive electronic parts such as satellite relays. My employer was very happy to have someone from within the company take on the job and it saved me from having to drive to another jobsite while providing me with a skill that I still make use of today.

I actually enjoyed doing that very much and trained myself by bringing in different cheap thrift shop finds such as old wafflemakers, hand tools and kitchen utensils to practice on before taking on the delicate work. This idea is well worth trying for modeling purposes and an easy way to get good at material removal before trying it on any models, especially considering the prices for having such work done by someone else. This is a good use for older or less valuable models like those Tyco or other items many of us have or can easily locate.

GP30

I don't think that walnut shells are fine enough to get into the small grooves like door lines etc ,areas like grills and other fine details. Aluminum oxide or baking soda are like powder and both work great on models getting all the paint out of those hard to get areas...........Joe

I was looking to regrind the walnut shells to make them small enough to be useful for the detailed work. The price of the stuff when sold as a grit blasting medium is what was holding me back until now as I have already invested in the tools from industrial strength sand/bead blasters down to the hobby sized ones. I am hoping to use the walnut shells to get as good of a result as they get when using the new plastic pellet systems for vehicle restoration out here.

Heck if I had the money I would rent time in one of them as it uses high pressure to apply plastic pellets and does a remarkably good job of cleaning rust and paint off of an item without destroying the basic material. I was out Friday afternoon looking for an older vehicle to eventually restore for use as a daily driver and more than a few of the candidates would definitely be put to the gun that way if could afford it. My favorite was a 1940 Plymouth 2 door that an acquaintance has in storage and will hold for me if I want it so time will tell.

GP30

I have used walnut shell and it is too abrasive for freight cars - removes plastic on the edges and gives the shell a "orange peel" texture. You can buy very small walnut blast media through Harbour Freight Tools. I thought about using baking soda and I am glad to hear someone tried it and it worked. Going to pick some up tomorrow and give it a try. The Navy used flour at one time on delicate surfaces to remove corrosion. It worked very well. I believe you can buy flour graded in different sizes. I am going to try flour also.

GP30 Wrote:
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> Has anyone tried the crushed walnut shells for
> paint removal? I have the equipment around that I
> use for tool cleaning and graffiti removal,
> including a newer gun that can work with the
> walnut shells. I have been considering getting one
> of the Harbor Freight blast cabinets for myself
> later this year and would prefer to use something
> besides the baking soda or glass beads. Thank
> you.
>
> GP30

In that case you may want to look for whole wheat flour as I have seen some that are rougher than normal flour. Good luck and please let us know the results.

GP30