Cheap Way to Sand Blast Large Glass

[Keith Outten]

The goal is to sand blast several glass panels that are 35" wide by 55" tall then paint the text before removing the mask.

The glass panels were sent to a local company to have a blast mask installed and the text vector cut.
Once weeding of the text was complete an inexpensive means of sand blasting was required.
We built a 13" square box from 3/4" thick PVC and covered the top with clear acrylic after cutting a 4" diameter hole.
We then cut several 8" acrylic disks with a 5/8" diameter hole to fit the blast nozzle. These would allow a 4" radial movement before the box would have to be moved.
We drilled a hole in the edge of the box to fit our shop vac hose and a couple holes on the opposite side to allow air to flow. The vacuum holds the box in place with just enough force to allow it to slide, it also captures all of the sand and dust. The glass beads are recycled several times by transferring it from the Vac to the blast pot.
After blasting we spray painted the text (first picture), the first coat was a khaki color primer, the second coat was Rustoleum Copper Hammer Paint.
In the last picture Art Edwards is blasting the second of four pieces of glass.

You can sand blast large pieces of glass using this technique and the seal is suitable for engraving installed glass.
The size of the box you build will depend on your equipment (vac and blasting pot), you must adjust the box and the cross-vent holes to suit your situation.
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[Mick A Martin]

Great idea Keith, do you have a picture of the finish project.

[Joe Pelonio]

Great creative solution.

[AL Ursich]

That idea would work with smaller signs too..... what a Novel Concept.... Fantastic !!!!

Thanks,

AL

[Keith Outten]

Mick, my track record taking pictures of glass is less than impressive but I will try to get a decent picture on Monday.

Joe, necessity is the Mother of Invention and we were under the gun to get this job moving. The deadline to have all four pieces of glass on the wall is September 20th.

Al, basically this is a poor man's sandblasting cabinet that can be portable Some of my wild haired ideas don't hold water but this one works so well I felt it was worth sharing. The system works well enough that you don't need to wear a mask, safety glasses are only a necessity if you make a mistake and remove the gun from the box before you cut off the air

I've been using medium grit glass beads on the glass panels. There is glue residue at the edges of the letters from laser cutting that needs to be removed so the lines will be pristine when painted. If I was not going to paint the glass I would use fine grit glass beads.

The next box I build will have a V-bottom which will help move the sand down to the bottom of the box since my vac is a $29.00 cheapo unit...but it works pretty good.

We started out blasting with the glass laying flat on the table which worked good. My back started to ache leaning over the panels so I decided to set the panel up on an angle. I had the top of a shipping crate so I decided it would hold the panel securely and the ledge at the bottom works good catching any beads that escape when I remove the blast box when we need to transfer beads from the vacuum back to the blast pot.

While I'm sure this would work with a siphon system the blast pot only requires about 30 psi to blast the glass. Our Home Depot air compressor isn't a big rig but it works good with this setup.
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[Keith Outten]

Hold onto your hats,

We requested several local sign companies to give us quotes to blast and paint five pieces of glass.
Only one company sent us a bid, it was over $75,000.00

My boss decided that we would do the job in house
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[Mike Null]

I am impressed. What a clever solution. Jeez--such high tech equipment!

[ray hampton]

Hold onto your hats,

We requested several local sign companies to give us quotes to blast and paint five pieces of glass.
Only one company sent us a bid, it was over $75,000.00

My boss decided that we would do the job in house
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that bid are too low-
way to go

[Rich Fennessey]

Were the masks laser cut? Can you use the same technique that is used for sandblasting monument stones? You just need a really big compressor for that and you may not be able to collect your abrasive.

Way to go Keith. You really show that imagination is the best tool.

[Keith Outten]

Rich,

The masks were laser cut on a 4 by 8 Kern laser engraver.
Honestly I could have cut vinyl masks that would have been easier because I wouldn't have had the burned adhesive from the rubber mask to deal with and the blasting would have taken less time. We outsourced the laser work and then had the panels sand blasted by the glass company but they didn't blast hard enough to remove the adhesive. In order to save the job I decided to make the box and use my blasting pot to do the final cleanup.

The blast pot requires less pressure than a siphon system because it uses pressure to force the sand to the hose. You can get by with a small air compressor using the pressure pot.
I have never sand blasted stone so I don't know if this system will do the job but I wouldn't hesitate to give it a try. The only thing I would do differently for stone would be to use another kind of blast media.

We found that removing the rubber mask worked best if we let the paint dry at least 24 hours, then we placed the glass in the sun to warm it up before we started stripping the mask.
Northern Tool sells a 50 pound bag of recycled medium grit glass beads for just $9.00
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[Keith Outten]

Here are a couple of pictures of a completed glass panel.
We placed a piece of white board behind the glass so there would be some contrast.
We will take a complete set of pictures next week when we hang the signs.
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[Rich Fennessey]

That looks great. Can't wait to see the final pictures.

[Mike Null]

Keith

what font did you use?

[Scott Shepherd]

Looks like Trajan to me.

[Keith Outten]

Steve is right the font is Trajan.

I'm running late this week because I caught a cold and have been in bed the last few days.
I have to get back in the saddle tomorrow or I'm gonna drown in my work backlog. Monday morning I will start the last piece of glass, so I'm already way behind on this project.
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