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Bob Quale
02-07-2006, 08:22 PM
I am looking at a sandblaster and am wondering if any one can recomend this one? or maybe one better? Thanks for the help.

Bob

http://www.harborfreight.com/cpi/ctaf/displayitem.taf?Itemnumber=34202

hrhoades
02-07-2006, 08:49 PM
This kind of sandblaster will give good results if you have enough good clean air and have a good place to use it. Sand will get everywhere and it will challange a standard shop compressor. I have a 5hp two stage compressor that puts out between 14 and 15 cfm at 100lbs pressure And I have to stop every 15 -20 minutes to let the compressor catch up. I do like one with a little more sand capacity as when the sand runs out you have to drain the tank to refill it.

3 Phase Lightbulb
02-07-2006, 09:06 PM
I have the same sandblaster. I've only used it for about 10 seconds because it makes such a mess but it did work really well for those 10 seconds http://bbs.homeshopmachinist.net//smile.gif

I plan to use it this summer outside on my driveway in the center of a 20x20' tarp. I plan to sandblast my buggy frame with it then recover the sand ontop of the tarp.

-Adrian

gsp
02-07-2006, 09:19 PM
I would use a larger deisel compressor.

I used a larger blaster, I belive a 100lb capacity. It's been 15 yrs since then but thats what we used to get the sand flowing. It took a minute to get the sand through a 2"x75' hose.

If you dont have much to blast, the large shop models will run it as posted above.

We used a bobcat to clean up the sand.

Dawai
02-07-2006, 09:21 PM
I saw a pressure washer with sand injected into the stream.. it worked better than the cheapo sand blasters we all get.

Blackjack, slag from coal, coke, is the preferred media. I have had it blasted under my skin, it popped through the surface of my arms for about a year afterwards. It is totally inert and you can eat it, breathe it.. the paint flakes thou, you don't want to.

Playsand, $2 a bag.. wear respriators. It is silica. Lil corkscrew type fibres that stay in your lungs forever and ever.

I keep getting water in my blaster, I got so damn mad I threw it into the woods, then gave it to a friend who asked about it.

I'll build the next one. I didn't like loading it, didn't like using it, didn't like it. (*hF 35 gallon?) model.

Dawai
02-07-2006, 09:27 PM
GSP:

Canned sand? a semi you add air to? YOu can't compare that to anything , any of US can afford. That is a ground-man's dream.

I have worked with my buddies who paint water towers, bridges, high work. I would take off, load sand into the pot and get a good workout. Handling the 100lb bags with one hand will give you a good one. Punching them to tear them and letting it flow into the pot, yeah. Make you feel alive.

Climbing them water towers suck. I'm too fat and sick now.

Bob Quale
02-07-2006, 09:29 PM
Thanks for the replies!
I have a 15cfm@100 psi compressor, I plan on using it out side, and letting the sand wash into the dirt. I have to do some frame rails, then who knows. It looks like this might be ok!

Thanks Bob

wierdscience
02-07-2006, 10:23 PM
I made this gun to work both in and out of a cabinet.It draws 12.5 CFM and syphons sand out of a bucket.It works much better than the el-cheapo syphon guns,but costs less than a pressure pot.The body of the gun is brass and the air and sand nozzles are crabide replacements availible from either Graingers or McMaster-Carr.

I used it to blash a wood planner frame and several other things.It took about 35-40 minutes of blasting to clean 30-35 square foot of cruddy painted cast iron,so not too bad.If your intrested I can post details and part#s for the bought pieces.

http://img.photobucket.com/albums/0903/wierdscience/gun2.jpg

Dawai
02-08-2006, 10:10 AM
Isn't 15cfm on the lower side? My compressor said it would put out more than that?

It smells hot every time it runs.. I think I lost some valves.

I sprayed two cars, HVLP, big orifice for metal flake, compressor ain't been the same. I had tried sand blasting with it. I had a bad day that day.

We got a big air tank I want to make a blaster out of. stand it up, make a dump valve on top, throttling valve on bottom.

Ever seen a 2 inch blast-line stopped up with wet sand? ohh crapola. I took a ball bat and beat the crap outa it as one of the blasters would hold it up.

Dawai
02-08-2006, 10:14 AM
For smaller jobs, I highly recomend the hopper type blaster Sears sells.

It will do wheels before you can get all the blaster out, load the hopper, hook up air, and do all the prep.. it is kinda wimpy, but that is dependent on your compressor.

NONE of the home blasters work like industrial. Them industrial jobs will peel it back. YOUR skin too.. I got hit with the "pilot" pop off dischage exhaust from the tank (deadman valve), looked down and I was covered in blood. I can remember blasting with a small blaster in tee shirt. The rebound is not crap. Rebound from a industrial job will penetrate the skin.

Duct Taper
02-08-2006, 10:15 AM
Here is one of the available sand/water blasting setups. You might need a wetsuit though!
http://www.catpumps.com/select/pdfs/30667.pdf

I have never tried one but I was thinking that it should keep sheet metal from warping when you sandblast.

And you don't need a big compressor.

[This message has been edited by Duct Taper (edited 02-08-2006).]

Dawai
02-08-2006, 10:16 AM
ONE more idea... Then I gotta go play with my pup.

I saw a guy blasting the store front of a building. I stopped, I thought I knew him.

His compressor consisted of a V-6 engine running on 4 cylinder and pumping air with the other two. NO compressor. It was blasting the heck outa the painted brick.

Herm Williams
02-08-2006, 11:38 AM
Hello
In the early eightes we used a Schramm compressor that really moved a lot of air.
It looked like a six cylinder farm tractor with two cylinders used as an air compressor.
just another idea.
re

Duct Taper
02-08-2006, 02:24 PM
Speaking of auto engines converted to compressors, I saw this on a Model A Ford site. Don't know the author:

"Starting in 1928 Gordon Smith built compressors using the #2 & #3 cylinders in an A engine while the #1 & #4 drove it.He designed a two piece head with reed valves and removed the lifters in 2 & 3 to make every stroke a compression one. You could buy his factory compressor for $850 and build your own using his kit for $250. He switched to "B" motors in '32 and did that for many years, finally using a Ford 302 V8 engine in his last design. There are many of us who have GS compressors in the hobby and use them as they put out a LOT of air."

micrometer50
02-08-2006, 05:15 PM
When I use play sand I put it in a big pot and heat it over a propane burner. As soon as it cools it goes in the blaster before it gets water in it. Don't put it in too hot or your seals will melt.

wierdscience
02-08-2006, 07:13 PM
<font face="Verdana, Arial" size="2">Originally posted by Duct Taper:
Speaking of auto engines converted to compressors, I saw this on a Model A Ford site. Don't know the author:

"Starting in 1928 Gordon Smith built compressors using the #2 & #3 cylinders in an A engine while the #1 & #4 drove it.He designed a two piece head with reed valves and removed the lifters in 2 & 3 to make every stroke a compression one. You could buy his factory compressor for $850 and build your own using his kit for $250. He switched to "B" motors in '32 and did that for many years, finally using a Ford 302 V8 engine in his last design. There are many of us who have GS compressors in the hobby and use them as they put out a LOT of air."

</font>

I got a P.K.Lindsey compressor that is built around a 360 Chrysler engine,one bank runs the other pumps.Puts out 175cfm @120psi.

The things work great,but the factory unloader systems suck.I about have mine whipped I think.

Dawai
02-08-2006, 08:41 PM
I thought all these car-engine compressors were homebuilt.

Weird: if you got some..
Lemme see some pictures.. come on.

When a compressor pump costs as much as a car engine, something is wrong. Seems to me someone should be converting the throwaway motors to pretty good compressors. a 4 cyl compressor tied to a motor seems a lot better than a 2 side by side. I saw a vw motor as a compressor once on a website.

wierdscience
02-08-2006, 09:45 PM
<font face="Verdana, Arial" size="2">Originally posted by David E Cofer:
I thought all these car-engine compressors were homebuilt.

Weird: if you got some..
Lemme see some pictures.. come on.

When a compressor pump costs as much as a car engine, something is wrong. Seems to me someone should be converting the throwaway motors to pretty good compressors. a 4 cyl compressor tied to a motor seems a lot better than a 2 side by side. I saw a vw motor as a compressor once on a website. </font>

I got the manual somewhere,I'll send you an exploded view.Remind me if(when)I forget.

wierdscience
02-08-2006, 10:39 PM
http://img.photobucket.com/albums/0903/wierdscience/Feb_08_001.jpg

For some reason they used a big arse automotive type valv on the intake and poppets on the exhuast.Notice that they used the water cooling off the engine in the head also.The intake is blanked off and goes in through a seperate manifold they fabricated from steel.

[This message has been edited by wierdscience (edited 02-08-2006).]

steve-ma
02-09-2006, 08:04 AM
I have a similar sandblaster as pictured in the original post. I have a two stage 7 hp compressor, and have had no issues with air supply. I only blast outside, because you can't control where the sand will end up. (unless you build a big enclosure, and I didn't think it was worth it to do so.) Mine looks similar (all them Chinese tools look alike) but came from Northern Tool. I did have trouble with the cheapo gun. The "valve" in the gun to shut off the flow of air and sand (it's already mixed at the tank) is simply a spring loaded piece of metal that pinches the rubber hose inside the gun closed. So if you do as I did and blast for a while at say "half throttle" you simply blast a hole in the rubber hose where it necks inside the gun. I fixed that, and learned to keep the gun full on all the time, and use the valves on the tank to control the process. So to start blasting I lock the gun "valve" on, turn on the air flow, (at the tank), then using the sand valve (at the tank) admit sand slowly until I have the right amount of flow to do the job. I have found that you can have too much sand flowing, in which case sand will clog the hose and you have to shut everything down and clean it out. The above process to me is cumbersome and therfore I only use the blaster on very large pieces (hence the outside, no enclosure) Anyway, you get what you pay for, and the small cheapo blaster wasn't a bad deal. I use Black Beauty media I get from a commercial sandblast house at about $15.00 for 100 lbs.