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3 Phase Lightbulb
11-09-2005, 10:37 PM
I want to get a sand blaster and was thinking about this one from Harbor Freight:

http://www.harborfreight.com/cpi/photos/47600-47699/47603.gif

http://www.harborfreight.com/cpi/ctaf/Displayitem.taf?itemnumber=47603

Does anyone have any experience with this unit? Will I need anythng else besides abrasive and an air supply with this unit?

-Adrian

wierdscience
11-09-2005, 10:51 PM
I don't have experience with that unit in particular,but lots of time in several different cabinets.

You will need a dust extractor,a cheap 1hp dust collector will work to put negative pressure on the cabinet while you are blasting to avoid making yourself sick.My cabinets at home and the one at work all have vaccums on them that exhuast the dust outside,it also helps keep the air in the cabinet clean and easy to see what you are doing.

The guns in the cheaper cabinets suck,get a better one like the ones that come with the Econline blasters.They use a foot valve to supply air to a jet in the back of the siphon,much more efficent setup.
I made my own version of said gun,I milled out the body and bought the replacement nozzle and jet from McMaster Carr.I can post a picture or two if your interested along with the part#'s for the nozzle and jet.

The other improvement I have made is to add a square baffle to the bottom of the sand cone in the cabinet.It sits about 1/3 of the way up from the bottom of the cone and has just the corners snipped out leaving four triangular holes for the sand to flow through as it returns to the bottom of the cone.The reason for this is if you run much abrasive in the cabinet the wieght of it alone will compact the area in the bottom of the cone and make it more difficult for the siphon action to work.

JPR
11-09-2005, 10:59 PM
I would like to see the pictures of your gun.

George Seal
11-10-2005, 12:39 AM
Adrian,

WWW.tiptools.com (http://WWW.tiptools.com)

they have sandblast equipment

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George from Conyers Ga.
Remember the early bird gets the worm, BUT it's the second mouse that gets the cheese.

Your Old Dog
11-10-2005, 06:05 AM
Wierd, good tip on the table in the bottom of the cabinet. Too much sand may be my problem because I always have a bear of a time in my cabinet.

Mine has a very small shop vac to keep down the dust and it works. Just wish mine had a better way to cover the inside of the plexiglass door to keep scratches down.

lathehand
11-10-2005, 06:48 AM
McMaster-Carr
window underlay 24"x 120" roll-$6.51- in the abrasive blasting section.
Works for me to make window last alot longer.

Allmetal
11-10-2005, 10:29 AM
I built my own cabinet and saved the money so I could purchase a 27 cfm 2stage 7-1/2 hp compressor. I think too often people buy expensive cabinets and then buy a 8-11 cfm compressor and then are not happy with the blasting performance.

I bought 3-4X8 16 gauge steel sheets to make my cabinet but it could have been done with 18 or 20 gauge, only the legs needed to be in 16 gauge. One sheet was bent to make the back, top, window area and front without making any cuts except for the window and framed with 1/2" angle iron to join the sides and funnel. This made the cabinet 48" wide. The big thing is to make the funnel as deep as you can so the sand doesn't hang up on the sides. I followed a TIP's model for most of my design.
I too made my own gun that was made from a 3/4" hydraulic T. I designed it so the compression ends can be unscrewed to replace the ceramic nozzle as well as the air nozzle plus the sand fed line to check for blockage. The T was modified so it would accept TIP's nozzles for easy to get replacements. I use a HF foot control for the air supply.

I use my dust collector used for my buffers and grinders to also remove the dust from the cabinet. Each machine has its own blaster gate so vacuum isn't lost when any one machine is in use including the cabinet. I have the dust collector hooked up with a remote control so it can be turn on or off as needed as I move through the shop.

I have just finished a sand reclaimer that vacuums all the sand from the cabinet as it is running. The sand is pulled off the bottom of the cabinet into round drum that allows the dust to be carried up and out to the dust collector and the sand drops down through a screen catching any junk that would normally plug the nozzle. The sand then drops into a funnel where the return hose carries it back to the gun. At the bottom of this funnel is located an air mixer that blends air and sand so a steady stream of sand is delivered to the gun without the sand pulsing that is so common with bottom fed guns. Lastly make good water traps and several so water is not allowed into air lines when blasting. Sorry for the long run on. Bob

Did I do better Evan? My Engish teacher just turned in her grave-again.

[This message has been edited by Allmetal (edited 11-10-2005).]

[This message has been edited by Allmetal (edited 11-10-2005).]

Evan
11-10-2005, 10:37 AM
Bob.

Paragraphs are your friend. You make a very good point though. You need air, lot and lots of air.

3 Phase Lightbulb
11-10-2005, 02:47 PM
I'm probably just going to get a basic sand blasting cabinet. Do I need to use certain types of abrasives with only certain types of guns/tips? I see sand blasting guns with different size tips (2mm, 2.5mm, 3mm, 3.5mm, etc.) etc..

-Adrian

billr
11-10-2005, 02:59 PM
good afternoon.

as luck would have it, i bought the little brother to that blasting cabinet yesterday. got it at the tractor supply store. they also have one like the larger one shown for more money.

i plan to use it to blast 1911 frames and slides before parkerizing them.

my question is about the blasting media. i wanted some aluminum oxide. all they had was glass beads and garnet.

will garnet work for what i want to do?

admittedly i am pretty ignorant about this. i have done some blasting on oil rigs and tanks [big stuff], but have never used a cabinet like this.

thank you in advance for your help.

happy marine corps birthday. 230 today.

peace.
billr

lathehand
11-10-2005, 03:45 PM
I have used aluminum oxide for a "vapor hone" finish on mold parts.You can get aluminum oxide from a rockhound/lapidary store. They use in in their tumblers.
You will need a very good finish, say 320 paper, before using alum ox.It will even out a finish but will not blend cutter marks.
Everything I parkerized for my 1948 Harley was glass beaded first.Blueing will need a better finish than parkerizing.

mrennie
11-10-2005, 06:48 PM
I am cheap, so I built my own. Looks very similar to the one in the picture. Cost me $75. I used 3/8" plywood for the body (caulked all joints), and 2"x4"s for the legs. I bought a cheap $15 siphon feed sandblaster gun and hose that justs sits inside the cabinet. Installed a small flourescent light, and used the glass window from an old stove to look through and the wire rack for the work table. To keep the glass from etching I bought $5 worth of that plastic film your Grandma puts on her coffee table, and it justs sticks on the glass by static. Once it is beat up, I remove it and stick on a new piece.

A shop-vac with the fine filter bags is connected to the top to remove the dust. A pair of long sleeve gauntlet gloves finish it nicely.

After 5 years, it still works well, no complaints. I use glass beads. After having one you sure do appreciate what you can clean up in a short period of time.

Allmetal
11-10-2005, 07:50 PM
Adrian, I have tried most of the different types of abrasives that TIP's had available plus using just plain old bank sand that I can purchase from a local sand pit which has been graded and dried for $20. a ton.

The type of abrasive you choose will depend on the type of material you are blasting and kind of finish you want when done. I have used both silicon carbide and aluminum oxide which will last a long time and produces almost no dust in the cabinet but they are hard on your nozzles and glass windows. They also produce a courser finish than sand or glass shot since they have sharp edges and sand and glass are round shaped. I haven't tried any of the plastic media yet but they say it produces a finish nicer then glass shot with no damage to the piece blasted but it's slower.

My main reason for using bank sand is I have to blast out sand cores from castings I produce in my foundry and this sand just gets mixing into the blasting sand in use. The only problem with using sand is it doesn't have much durability and will quickly turn to dust but it does leave a nice satin finish on the pieces and is cheap to replace. I have my dust collector vented outside and you can tell when the sand has to be changed because it looks like smoke coming out the vent stack.

As far as selection of a nozzle size will depends on your cfm air supply. I have mine sized so the compressor can maintain about 150+lbs. when running constantly. As the ceramic tip nozzle starts to enlarge you will start to loose the suction on the sand feed line and the media delivery drops off and you will have change tips. TIP's has matching ceramic tips and air nozzles so you can get the best media delivery for different amounts of air supplied. Bob

ulav8r
11-11-2005, 10:17 AM
I blasted several guns while at theColorado School of Trades. Used masonry sand on top of 320 sanded finish. It gave a very flat finish after bluing that would scratch very easily. Found that sttel wool with oil would nock off the high points and make the surface show scratches less. Best was to steel wool after blasting but before bluing.

I would recommend using glass beads instead. No other treatment needed before bluing.

3 Phase Lightbulb
11-11-2005, 10:36 AM
Thanks for the info guys, I appreciate it.

I mainly want to sand blast parts just to clean them up a little prior to washing and TIG welding them up. I'm getting lazy with the wire brush and would like to add a little fun to the prep process and I figured sand blasting would be more entertaining than wire brushing http://bbs.homeshopmachinist.net//smile.gif

-Adrian

wierdscience
11-11-2005, 09:17 PM
http://bbs.homeshopmachinist.net//Forum1/HTML/014254.html


Gun pics.

Evan
11-11-2005, 11:23 PM
Hmmm. A sandblast cabinet window sounds like an ideal application for aluminum oxynitride ("transparent aluminum"). $$$$$$$$

HTRN
11-12-2005, 04:12 AM
Heeheehee... I just got a Dayton "tabletop" blasting cabinet, complete with media for free, along with an assortment of other junk - it came from a shop cleanout that a buddy did. I was invited to pick over the "scraps" IE the stuff that isn't worth his time to move, store and try to sell... Sometime this weekend I have to get off my ass and actually build the stand I've been planning - already been collecting bedframes for a couple of weeks..

Tommorrow, I got a pick up an air compressor from another friend..


HTRN

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This Old Shed (http://thisoldshed.tripod.com)

burnlast
11-12-2005, 07:42 AM
3 Phase,
May want to take a look here for that cabnet!


http://www.homier.com/detail.asp?dpt=&cat=&sku=02763

It's the same one just different stickers on it. I have one,the only thing I didnt like about it was the POS light that was with it.I replaced it with a cheap halogen work light.Other than that I am very satisfied with it.One thing you need to do when you put it together is to use silicone caulk on all joints as you are putting it together

3 Phase Lightbulb
11-12-2005, 09:15 AM
<font face="Verdana, Arial" size="2">Originally posted by burnlast:
3 Phase,
May want to take a look here for that cabnet!


http://www.homier.com/detail.asp?dpt=&cat=&sku=02763

It's the same one just different stickers on it. I have one,the only thing I didnt like about it was the POS light that was with it.I replaced it with a cheap halogen work light.Other than that I am very satisfied with it.One thing you need to do when you put it together is to use silicone caulk on all joints as you are putting it together </font>


I already bought this one yesturday:

http://www.harborfreight.com/cpi/photos/47600-47699/47603.gif

The one you pointed out is different but maybe it has the same gun? Mine has a shipping weight of 163 lbs, and the Homier is 90 lbs.

-Adrian

New chips
11-12-2005, 08:04 PM
I made mine out of 2x4s and 1/2" partical board made a flat bottom with 4" pvc pipe on end that drops into 5 gal bucket. I drop my syphon gun down pipe and just push sand over to pipe every once in a while. To keep sand from eating up the cabinet I lined it with innertube rubber from old earth mover tube.I mounted a under cabinet hologen light in top and made a 2" wide baffel chamber across the top of the back. I do not use a fan and have not had a problem with fog but I only use it once in a while for quick jobs. Cost for cabinet and hardware including air regulator $75.


[This message has been edited by New chips (edited 11-12-2005).]

chief
11-12-2005, 08:36 PM
Extra gloves and extra windows.

gunsmith
11-12-2005, 08:56 PM
I have had this same unit for about two years now and no problems. It will blast just about any sand. I prefer silica which we can still get around here. I use a vacuum with a fine filter used for drywall dust to extract from the cabinet. I change the tip on mine gun to a larger one than the ceramic ones supplied. The tip I use is just a piece of steel with a 1/4" hole and it seems to work the best. My only complaint is the light. It is worthless. Won't come on most of the time and even when it does it is to dim and on the wrong side of the cabinet. I am going to put in two new lights to replace this one and they will be mounted just above the glass pannel. Hope this helps with your decision.

fponzani
11-13-2005, 08:11 PM
Not to hijack the thread, but I've oft wondered...why are most sandblasting cabinets side loading instead of top loading? With doors on the side, either the end(s) of the cabinet must be kept clear or the cabinet must be on wheels so it can be pulled out.

3 Phase Lightbulb
11-13-2005, 08:29 PM
<font face="Verdana, Arial" size="2">Originally posted by fponzani:
Not to hijack the thread, but I've oft wondered...why are most sandblasting cabinets side loading instead of top loading? With doors on the side, either the end(s) of the cabinet must be kept clear or the cabinet must be on wheels so it can be pulled out. </font>

That's so you can sandblast a 10 foot long pole and make a big mess http://bbs.homeshopmachinist.net//smile.gif ... That's what I'm going to do with mine probably http://bbs.homeshopmachinist.net//smile.gif

-Adrian

PTSideshow
11-13-2005, 09:53 PM
Nobody has mentioned the biggest reason why sand is not the safest media to use in a blast cabinet. If you are using silica sand, the dust is very fine and causes silicousis (spelling may be incorrect). You not only must have a very good dust collection system. but you should also have a postive pressure air hood. Incase your cabinet leaks. The only advantage silics sand has for most people is it is cheap. in some locallities using silica to blast outside will get you a rest at the cross bar hotel. Go to www.eastwood.com (http://www.eastwood.com) and check out thier section on blasting and media. In Michigan they sell a media called black beauty. it was only a buck or two more a bag than the silca. Eastwood had a chart that listed various media and suggested uses.

------------------
Glen
Been there, probally broke it doing that

SJorgensen
11-14-2005, 01:17 AM
There are three useful modifications to make on these blast cabinets. The first modification is to put some steel window screen material below the grate. This sifts the sand and keeps the paint and rust and chunks of dirt from clogging your nozzle.

Another problem is with the siphon tube. It will often clog because it will draw in a slug of sand. One method to fix this is to put a washer over the end. This creates a smaller orifice and the sand coming in is broken up and flows better.

The last problem is some way to keep the window cleaner. Perhaps a wiper. Perhaps a roll of clear plastic that can be advanced. Perhaps a button that blows the sand clear.

Spence

[This message has been edited by SJorgensen (edited 11-14-2005).]

john hobdeclipe
11-14-2005, 08:55 AM
The side door makes it easier to load large heavy objects...easier & safer than lifting up and over the front panel.

wierdscience
11-14-2005, 07:23 PM
<font face="Verdana, Arial" size="2">Originally posted by PTSideshow:
Nobody has mentioned the biggest reason why sand is not the safest media to use in a blast cabinet. If you are using silica sand, the dust is very fine and causes silicousis (spelling may be incorrect). You not only must have a very good dust collection system. but you should also have a postive pressure air hood. Incase your cabinet leaks. The only advantage silics sand has for most people is it is cheap. in some locallities using silica to blast outside will get you a rest at the cross bar hotel. Go to www.eastwood.com (http://www.eastwood.com) and check out thier section on blasting and media. In Michigan they sell a media called black beauty. it was only a buck or two more a bag than the silca. Eastwood had a chart that listed various media and suggested uses.

</font>

While it is true that Silica sand causes sillicosis it is also true that ANY particulate inhaled into the lungs will cause damage.Black beauty and the other slags are no better. It's just that they haven't gotten the attention of OSHA and the "Legions of Evil"(lawyers)


[This message has been edited by wierdscience (edited 11-14-2005).]