Pressure washer sand blasting

[pfarber]

Took most of the day to figure out the sand blaster.. but once it works and set up properly its quite quick.

Pros:
Quick
No dust
Comparable to media blasting as far as results are concerned
As long as you have sand, gas and water it works fine.
Best for LARGE objects with not a lot of crevices.

Cons:
Noisy (pressure washer, wand)
Large area needed (all that sand has to go somewhere)
Large wand extension is awkward (can be fixed).
You need A LOT of sand, cheap. The wand I have is rated at 750lbs of sand per hour. Half a ton of sand per hour!!!!
Small objects not practical.


I'll post a video later. But the results are comparable with a media cabinet and flash rush is easily handled with a phosphoric acid wash.

[pfarber]

[youtube]eAOatPsPWSk[/youtube]

[pfarber]

Found a local wall and block business about 4 miles away that has sand... $35/ton. That should save me a TON of money (ha!)

Compared to screened sand at Home Depot 50lbs @ $5 (play sand still has pebbles in it that need screening)

2000/50 = 40bags * $5/bag = $200/ton

vs

$35/ton

With it being in the 70's this weekend drying sand should not be a problem. 1 ton of sand should be about 1.5 hours of blasting time. But the pressure washer only hold 1 qt of fuel... so about every 20 minutes it will be empty.

[pfarber]

Well, there is a slight problem with bulk sand... maybe its just a May 4th thing... but when they took the first scoop out of the bay and into the truck about the top 3 inches were dry sand.... the rest was dark brown.... WET! So I have 1 ton of sand in my back yard spread out on tarps trying to dry out. There may be about 400lbs dry enough to use... but once I start the pressure washer it most likely will get wet again.

CURSE THE SAND GODS!

Still, not bad enough to hump 40 bags of sand from HD. Still got lots of cabinet parts to blast.

[pfarber]

Went through about 300lbs of sand today... as well as 2 tanks of gas.

The pressure washer sand blasting is slower, but most of the slow downs are my own fault.

I use a 5 gallon bucket as a hopper. The sand can be a little wet, and you can feel the hose/wand 'chug' when it hit damp sand. When using dry sand the only way to tell its working is by the clean metal and the water, once it splashes, is slightly brownish. My chebby chassis is less than 6 feet from the sand on a tarp... and the oversrpay is not affecting it.... its kind of amazing how 'contained' the sand/water is. Other than water on the ground from 10 feet away you'd never know what was going on.

The only serious issues are pebbles. Clogging the nozzle is still an issue, but once you get a 'poker' figured out unclogging the nozzle is a 20 second affair. The sand I have is 99% sand... but a stray leaf or stone stops all work till you get it out. I can tell by how the water's spraying out whether the clog is in the tip of the line... really speeds things up when you know where to look.

All that sand and gas I was able to get a bit done.... as I said its slow going... but short of spending $1k to rent a compressor/blaster for a week or paying someone I'm ok with the slower pace. The results are on par with conventional blasting. Will have pics tomorrow. I want to see how bad the frame flash rusts and how the phosphoric acid handles it.. I should get done the frame tomorrow.

A second person to tend to the hopper (fill it, screen out stones) would make things much faster.

[pfarber]

First day of sandblasting... look at frame and after the first few hours of learning :

[youtube]oG9c1EKlDJ0[/youtube]

[pfarber]

End of first day:

[youtube]PmW61v7_ZPM[/youtube]

[pfarber]

Second day... starting out with the what the metal prep looks like:

[youtube]vSFz2ZzX-6U[/youtube]

[pfarber]

Another day on the the washer....

[youtube]7ajbduCBufc[/youtube]

[pfarber]

End of the second day...

[youtube]rsC3S7ndzD0[/youtube]

[pfarber]

Getting the hang of it all now. Screening the sand is a must. It goes A LOT quicker than hoping that nothing will clog. I get about 3-4sq ft from a 5 gallon bucket of sand (maybe 50-60 lbs of sand).

The ceramic nozzle is shot. Did not last long and I am pretty much wasting sand now. A new nozzle is $25+ ship, but for $100 I can get a new 'industrial' nozzle that has a carbide nozzle. Since I can't find a carbide nozzle for the wand I have now I may simply buy a new kit.

I wish my air compressor would keep up like the pressure washer does. I can go through 4 buckets of sand (about 250lbs) before the gas runs out.. thats like 45 minutes of blast time.