Sandblasting

[curly 0]

Hey guys I know I may sound like a dummy but I am in process of tearing my B11 down for restoration. Some of it I will sand while oyher parts I may sandblast. I have a small sandblaster but my problem I have is my sand does not seem to feed as it should. Do I need a special blend of sand--Certain air pressure needed or what? Any suggestions will be appreciated.

curly in kaintuck

[TT-(Moderator) 1,127]

If you're using yellow sand ("play sand" as I call it - 'cause we put it in the sandbox. ) it won't feed worth a darn. The screening procedure leaves too broad of sizing of the grains - right down to almost dust.

Regular white sandblasting sand is more consistent in size and contains very little "fines" -- or dust. It works best for sheetmetal while the more coarse black sand is good for rustier thick steel and cast parts.

Another important issue is moisture in the air supply. Too much will cause the machine to plug up. If you plan on doing much blasting, invest in a decent inline moisture trap - or at least buy some disposable moisture filters. :banghead:

[curly 0]

:banghead: Thank You TT seems I can always depend on you to come thru for me. I appreciate it.

curly in kaintuckee

[Kelly 1,028]

I get my sand from our local lumber yard, they sell coarse, and fine, for sand blasting, I use the coarse on everything, this sheet metal is pretty thick, just don't hold it in one spot to long, and the type of blaster makes a diff. if you have the type with the tube you stick in the bucket, they work but will take a little more work, or the pressure type that you fill a tank and put pressure to with your compresor, they work much better, and yes you need a water trap of some kind.

Make sure you use protective eyewear, I use dollar store goggles I buy a bunch at a time, they are cheap, eye's only come two to a person.

[linen beige 14]

The other guys have hit on most of the important stuff. But there is one important point about using lumber yard sand from Kentucky. It is FULL of clay, and the clay makes the grains stick together. Also, just as important as having dry air, is having DRY SAND.

You can blow lumber yard sand through a piece of 6 inch drain pipe about ten feet long and get most of the dusty clay out of it. The sand will loose velocity inside the larger pipe and can be collected in a bucket at the other end. Just place a small box fan where it blows gently across the far end of the pipe and the lighter dust will blow away, leaving cleaner sand falling into the bucket. If it is damp, the easiest way I've found to dry it is to simply spread out about an inch layer on the garage floor and let it sit overnight. The floor will soak the water right out of the sand. Sweep it up and let the floor dry a day or so before spreading the next batch out to dry. I know that sounds messy, and can be, but a side benifit is that any clay left in the sand will also soak all the oil stains right out of the floor.

As for eye protection, BUY A HOOD! Hoods not only keep the sand out of your eyes, they also keep it out of your hair, ears, back of your shirt, etc. And work in a ventilated area. The paint on these old 'horses is full of lead!

[Butch 194]

We in Jersey have a great selection of sandblasting sand because it is mined here. 5 years ago I paid $3 for a 100 lb bag. A couple weeks ago I paid $12 for a 100 lb bag. After that I ran out and bought a blasting cabinet. Now I don't have to worry about throwing the sand away.

Curly I would say your compressor has a lot to do with it also. Are you using a very cheap, plastic, unsealed sandblaster or a metal one that is enclosed that is a steel tank? Unless you have a 2 stage compressor with a lot of available CFM, say 18 CFM at 90 PSI, I would use the smallest available nozzle you can get and use a finer sand. I don't know what you guys have available in Kentucky. This way a smaller compressor can at least keep up for a couple of minutes. A large nozzle would require a big compressor. I have a 5 HP 60 gallon single stage compressor that runs on 220v. I have to use the small nozzles and fine sand and I can only run the blaster a few minutes before the compressor kicks back on and builds up pressure. The finer sand will also give you a smoother finish. But you lack the speed of a more course sand.

If you have one of those cheap $50 plastic gravity blasters you aren't gonna have much luck. I paid around $110 for a sealed unit from Harbor Freight about 5 years ago. It holds 110 lbs of sand and has a cheap water seperator on it with a couple different valves to adjust the airflow/sand mixture. It works pretty good for the price.

For a $150 you can go to the Tractor Store Company and get a compact blast cabinet for doing parts up to about 20" long. You will have different kinds of media to chose from and the best part is you are not throwing it away like a sandblaster. This blast cabinet also requires less CFM than a sandblaster.

When it comes to painting nothing looks better than clean, blasted metal!!!

Butch

S. Jersey

[Sarge 3,462]

Just a few notes/hints -

If using one of the many types of suction units , make certain the air tube doesn't become plugged . Some , the air tube is at the bottom of the intake pipe and mixes air with the sand so it can flow - so keep it near the surface of your material . If buried too deeply in the bag/container it cannot mix air and just doesn't work well . Other types have an inlet pipe above where the material is picked up, out of the cheap ones these work better but also can get plugged with dust or clay . Best types are pressure pots , these force a mixture of material/air into the hose and usually use a deadman type of spray handle . Really expensive units have a remote which uses a pressurized air supply to the handle's trigger . Cabinets are sweet but remember even small ones need some sort of dust collector to be able to see what you are blasting , and that's the expensive part .

Please, read the label of what you are buying , make sure the material is appropriate for blasting . Normal "play sand" , "mortar sand" , or "general purpose" sand is not to be used for sand blasting - it contains silicates that are unbelieveably damaging to your lungs !! Most bagged sand types now are required by federal law to have a warning not to be used for blasting if it contains silicates .

Sarge