Custom-Made Sandblasting Cabinet

[GoodWComputers]

So, a few years ago I got the random inspiration to try my hand at sandblasting. I think at the time I wanted to clean up a used performance part I had purchased for the Mustang I used to own. I looked at the various options for buying a cabinet (Harbor Freight) and decided, what the heck, I can build that!

I looked at the various models online, figured out the dimensions I wanted, and built one using mostly free wood - 2x2s for the frame (which were 2x4s cut in half lengthwise), 1/2" plywood leftover from a friend's house to protect the windows during a hurricane, and aged 4x4s (for the legs) leftover from a fence project. I bought four wheels from HF and had this:

 

[GoodWComputers]

Unfortunately, I moved shortly after this was done and the project sat unfinished for a year or two until my Mow-Kart project re-inspired me to finish it. Looking at it, I realized I wasn't far away from finishing it - build the sand capturing funnel, build a window/door, and rig up the various connections for sandblasting.

Building the "upside down pyramid" proved to be a heck of a challenge. I even recruited a buddy of mine that is a math major in college to help me figure out the angles, and even he was stumped. The problem is that it's not a right angle pyramid, and most formulas that calculate the angles are for that type only. I finally found this online:

Surface Area and Volume of Pyramid - Geometry Calculator

The key was to find a formula that gives the angles for a rectangular-based pyramid. So, I built the pyramid and attached it to the base using Loctite construction adhesive in a caulking gun. I didn't want to use screws because of the angles of the plywood.

 

[GoodWComputers]

As this cabinet is for sandblasting, the entire things needs to be almost airtight, which meant SEAL EVERYTHING! As the entire thing is made out of wood, I wasn't sure at first what to use, but with the advice of the local hardware store, decided to use more of the Loctite construction adhesive on all of the seams. This proved to be a good choice, because it has a decent working time, doesn't shrink that much when it dries, and is paintable. Three tubes later, I had sealed every single seam on the entire cabinet, inside:

 

[GoodWComputers]

...and outside:

 

[GoodWComputers]

Next came paint. I used an epoxy-based off-white paint on the inside that was leftover from a renovation job because it is extremely durable. I only put on one thick coat, but may go back later and put on another coat:

 

[GoodWComputers]

Fast forward a few steps - I forgot to take in-between pictures.


I had a gallon of some cool looking "fire engine" (I don't know the actual name of this color) paint and thought the cabinet would look way cooler this way in my workshop - after all, one could consider this furniture for my shop!

Picture #1 shows the window/door and gloves installed. I made the window/door out of 2x2s that I cut on various angles to create a beveled edge. I then cut a seam on the inside with my table saw for the plexiglass to fit into the frame. I used foam strips, the kind you buy for doors to seal out draftiness, on all four sides underneath the frame to seal it. The gloves I had bought a while back (don't remember the website, although I think they're available at HF). I used a 5" hole saw bit to cut the access holes, and stapled them in for now - I am going to either build a ring for mounting/sealing them or buy a glove "mounting" kit.

Picture #2 you can see the air inlet connection with an air dryer/moisture remover hooked up - this is crucial for sandblasting as you need VERY dry air for your gun to work. I will install a more permanent mounting for the air dryer at a later point, as hanging like it is now isn't very stable and makes the connections prone to leak air.

Picture #3 you can see the shop vacuum connection - this is also crucial to the operation of the sandblasting cabinet as it serves two purposes - to help remove fine dust inside the cabinet for visibility, and to create a vacuum inside the cabinet so that dust isn't released into your workspace. In picture #2 you can see an air inlet hole I drilled - before this hole was made the vacuum inside the cabinet was so strong the plexiglass window was bowing in so much I thought it was going to crack! If you build your own cabinet, you'll have to experiment with finding the best air in/air out mixture for you. I put a PC fan vent cover over the hole.

Picture #4 shows the bucket of sand underneath the funnel with the siphon and hose going up to the inside of the cabinet. This setup works for now, although I will be buying a pressure pot later on that will greatly improve the efficiency of my sandblasting.

Picture #5 shows an extra air tank I have that has a T connection; the right side goes to the air dryer and then into the cabinet to the gun, the left side is receiving air from my air compressor with the big tank. There is a pressure gauge and cutoff valve installed on the connection to monitor the pressure while I'm working and cut off air to the gun when I'm done.

 

[GoodWComputers]

Here is the inside of the cabinet. You can see where the air connection comes in as well as the air inlet hole to relieve pressure from the shop vacuum. I installed two fluorescent light fixtures I had laying around and ran the wiring to the back of the cabinet where I just plug them in whenever I want to sandblast.

The bottom of the cabinet has four metal pieces of mesh grating, cut to fit inside the cabinet. This is so that you can lay parts down while allowing the sand to fall down the funnel. I can fit a lot of parts in here at once, although there really isn't any need to put a bunch in at once as the shop vacuum clears the air so quickly that opening and closing the cabinet and releasing dust into the air isn't much of an issue.

Right now the cabinet only has one pair of gloves - later I will purchase another pair and install them to the left of each current glove so that you can work on both sides of the cabinet.

 

[GoodWComputers]

Shot of the inside of the cabinet while working. I've already sandblasting half of my old Tecumseh engine.

 

[GoodWComputers]

Carb cleaned and flywheel halfway done:

 

[GoodWComputers]

This is probably the best example I have so far of why I love this sandblasting cabinet. Here's a before and after shop of the head cover:

 

[GoodWComputers]

I forgot to add earlier the type of media that I'm using for blasting - so far I've only used regular playsand that you buy for a children's sandbox. I already had a bag at home and had read online that a lot of guys use it, and as you can see it does the job just fine.

That being said, I have seen multiple warnings about using playsand because there are potential health hazards. When you sandblast with this stuff, it creates a very fine silica dust which when inhaled can cause silicosis - nasty stuff. Even though I have a shop vacuum hooked up with a good filter, I still don't really trust it that much and have been wearing a mask while in the workshop. I've stopped sandblasting for now and don't plan on resuming until I go and buy some media that is actually designed for sandblasting.

This is not to say you can't use playsand - obviously I used it with great success so far. Some that use it run into problems with the sand containing moisture or other debris that will clog your gun. Keep that in mind.

 

[GoodWComputers]

Video while sandblasting the engine:

Custom Sandblasting Cabinet Test

 

[DeathStarr89]

Nice work!

You can get good media at HF for really cheap.

I've had glass media in mine for a long time and it does great. It does embed into cast aluminum so you have to scrub the parts with brake cleaner and a brush after. Works good on steel and everything else that i've used it on.


I don't know if you've done it or not but you should run a grounding strap between the gun and the base plate and anything else metal you have then to an earth ground (or just to the Compressor chassis). Static is an issue and it will get you at some point.. i have a metal HF cabinet and i get zapped if i'm not careful. lol


oh yah, and get used to replacing the window. I finally started to layer plastic wrap under mine so i didn't have to keep cutting out new pieces of plexi for it.

 

[GoodWComputers]

Here is the compressor I'm using to provide air for sandblasting. Keep in mind that sandblasting requires a TON of air. Even this 26 gallon air compressor is almost not enough.

The only way I'm able to get away with it is because I have the auxiliary tank hooked up for extra air initially and I only do small items at a time. Anything larger or for longer periods of time will require a bigger air compressor that is rated to put out greater cfm's at a high pressure, probably around 90 psi. I had read online that most guys use a compressor that puts out at least 10 cfm @ 90 psi, so I'm surprised that I'm doing so well with my setup.

 

[jamyers]

NICE!!!


Sent from my iPhone using Tapatalk

 

[DS13]

I would assume ya know not to touch the item that has been sand blasted right?

 

[GoodWComputers]

You can get good media at HF for really cheap.

Fortunately my local Ace hardware has blasting media. The closest HF to me is about 35-40 minutes away.

I don't know if you've done it or not but you should run a grounding strap between the gun and the base plate and anything else metal you have then to an earth ground (or just to the Compressor chassis). Static is an issue and it will get you at some point.. i have a metal HF cabinet and i get zapped if i'm not careful. lol

I was worried about that issue as well and had read about that with other cabinets, but I'm wondering if I'll have to worry about that as the entire cabinet (minus the mesh bottom) is made out of wood.

oh yah, and get used to replacing the window. I finally started to layer plastic wrap under mine so i didn't have to keep cutting out new pieces of plexi for it.

That was definitely another concern in the designing of this cabinet. I already had a sheet of plexiglass handy so I used that, but I considered getting tempered glass as well. I have a roll of saran wrap that I've been replacing before every session. Working great so far!

 

[GoodWComputers]

I would assume ya know not to touch the item that has been sand blasted right?

Why? Oily fingers?

 

[GoodWComputers]

I'm willing to offer this to anyone on here - you ship me your part and provide return shipping, I'll sandblast it for you for free!

 

[crazzywolfie]

that is pretty cool. according to princess auto the Siphon Feed Abrasive Blasting Gun's they carry require 4-4.5cfm@90 to runs so you would probably ok to run a bit longer especially with that extra tank hooked up. also how do you like the siphon feed Gun? in the summer i do a fair bit of sandblasting and would like to cut down on the amount of sand that is wasted.