Jump to content
Mark

Upgrading Sand Blast Cabinet

Recommended Posts

Hi all

I've owned a floor standing Sand Blast cabinet for years, has a large hopper, with gun and trigger set up, seen the same type supplied by various brands. I used it once to sand blast a set of wheels, but never again, took forever, and then very occassionally thereafter. I have a 14cfm 10 fad compressor that can maintain a constant high pressure supply, but often got blockages to the gun and constantly banging on the hopper to get things moving. It's just been easier to use thinners and a wire brush for the majority of things I've needed to strip.

It takes up a lot of room and was thinking of flat packjng it, but have seen kits you can buy to convert it to a foot peddle operation with a more professional looking gun, and the grit is fed to the gun from the bottom of the hopper, so gravity assisted. I would also like to add brighter lighting.

Anybody converted their blaster using a kit or DIY, or got any suggestions to improve the current set up?

Thanks

Mark

 

Share this post


Link to post
Share on other sites

Knowing less than nothing of sand blasters, I've looked at some and wondered at the sand/abrasive reservoir below the cabinet.    I know, Venturi's Effect is supposed to suck it up and inject it into the air stream, but your experience Mark wowuld seem to show the limitations of that.

Another technology that injects particles into a gas stream is spray welding.   Again, I know nothing of that, but I note that the small reservoir of powdered metal is mounted above the gas jet, and falls by gravity into the flame.

No doubt a large hopper of sand is more conveniently postions below the cabinet.     A smaller supply hopper above would need refilling, but might run more reliably?

JOhn

Share this post


Link to post
Share on other sites

Chuck your stuff in the tank first, that gets 95% off then just finish off in the cabinet if needed.

 

 

190520132717.jpg

Share this post


Link to post
Share on other sites
17 hours ago, RedRooster said:

Chuck your stuff in the tank first, that gets 95% off then just finish off in the cabinet if needed.

Ah that looks like what I need. What's in the soup and how long do you leave things? 

Share this post


Link to post
Share on other sites

Garage chemistry at its best.

Cheap washing machine powder.

Connect a battery and charger Negative to what ever is in the tank, Positive to the sacrificial metal bar.

Leave it overnight, you will see when its working as the water eddys about.

It tends to work better with grotty rusty water

Share this post


Link to post
Share on other sites
1 hour ago, RedRooster said:

Garage chemistry at its best.

Cheap washing machine powder.

Connect a battery and charger Negative to what ever is in the tank, Positive to the sacrificial metal bar.

Leave it overnight, you will see when its working as the water eddys about.

It tends to work better with grotty rusty water

I did loads of stuff for my spitfire like that. Works brilliantly, though some stuff took a bit longer than expected. I had a large plastic tub, could get a steel wheel in there. Isually looks cruddy when ib=nitially pulled out the tank, but a rinse and brush and the results are brilliant. 

(never use stainless or galvanised as the sacrificial anode, fumes are very nasty)

Share this post


Link to post
Share on other sites

cool, I'm going to give it a go. Sick of hours using a wire wheel on the drill. 

Share this post


Link to post
Share on other sites

With apologies to Mark for hi-jacking the thread, I am now an electrolysis convert. Thanks RedRooster. Only wish I'd tried it earlier in my front suspension refurb.

As a vaguely scientific experiment, I put one badly-rusted dust shield in the electric soup overnight. Next evening I fished it out and laid it next to its partner thus:

DSC_6643.thumb.JPG.ecfcd171938ae8261ab2c92f21906ff7.JPG

Then I gave them both a good 5-10 minutes of wire wheeling and the difference became a lot clearer:

DSC_6644.thumb.JPG.8caa94c48a11759fa2e9e30adafc1c0f.JPG

The paint mostly just fell off the electrolysed one, very pleasing. The same treatment on the wishbones saved me hours! 

My battery charger is ancient so doesn't need a battery in parallel. I used washing powder in the solution, and had current of around 1 amp. Now if I can find a way to capture the hydrogen bubbles I can make a rust-powered fuel cell electric Spitfire... 

Share this post


Link to post
Share on other sites

I'e used eletrolysis in the past and found that it works fine, but no better than some easier non-electrical methods.  One notable drawback of any electrolytic process is that it is generally line-of-sight, and is less effective in holes and other recesses.

Ed

Share this post


Link to post
Share on other sites

I did find it less effective on parts that weren't rusty, so it's got definite limitations. But I didn't find that line-of-sight issue was too problematic. If you can get some distance between the anode and cathode then the current is distributed more evenly over the surface of your work-piece . The lower wishbone was the only thing I had to do both sides of, partly because it was too large to get it all far away from the anode in my tub. 

It suits me anyway, horses for courses. 

Share this post


Link to post
Share on other sites

I used several anodes around the tub when I used it. Must say the solution gets pretty grim after a while, but still works fine. And seems that electrolysis works better than "at home" mechanical methods as it works in pits etc. point taken about holes/line of sight, but almost all methods struggle somewhere. One big advantage is no dust!

Share this post


Link to post
Share on other sites

Hi all

I will have a go at electrolysis de-rusting, and bought some Washing soda from Sainsbury the other day, ingrediants are sodium carbonate decahydrate.  Thought it was just sodium carbonate and not sure about the decahydrate, or if it's suitable for the process?

Made up a pick-up to attach to the bottom of the sand blast cabinet hopper. Made a copy of the original trap door and an additional narrowing exstension following the shape of the hopper, into a 90 degree sweeping bend. Hopefully this will help to keep the media flowing. I am going to get rid of the airline quick connect i fitted, and increase the supplied air line diameter that goes to the gun from the front of the cabinet, as it's pretty puny. Ive got plenty of pressure, think I need to increase the volume. 

Cabinet came with a 12 volt florescent tube which has never been bright enough for me, probably worse now as the cabinet must be nearly twenty years old, so just bought some 12 volt LED's which should be a lot brighter.

Also looking at either making or buying a cyclone device to go between the vacuum and cabinet to help separate out the waste.

 

20200522_191350(1).jpg

Share this post


Link to post
Share on other sites

That looks just the ticket, nice work. 40 years ago that would have been fitted to an FS1E

Share this post


Link to post
Share on other sites

Decahydrate just refers to the water in the crystals.  Once the crystals are dissolved in water, it becomes irrelevant.

Ed

 

Share this post


Link to post
Share on other sites

I had a cabinet with a 200L compressor. I found it so hungry for air. Blockages were also a problem for me. Ive got rid of it in favour of other more useful tools with the theory that if i need something blasting ill send it to someone to do it for me. That was about 5 years ago and haven't really missed it and it frees up a lot of space as i didnt need the huge compressor either so that went as well.

If i did need one again i would get a screw vain compressor.

Share this post


Link to post
Share on other sites

I have a bench mounted set up, sounds like it is smaller than yours.

Used it mainly for smaller bits and used glass beads as the medium.

Mounted an extra neon tube opposite the one provided and regularly sieved the crud out of the blasting medium.

Very handy during the rebuild/restoration. Similar sized compressor, so lots of pauses while the compressor catches up, but if you are retired you don't have to rush.

 

blaster.JPG

Share this post


Link to post
Share on other sites

Same as mine, the lid seal is crap and so is the little air filter, so changed mine for a DCOE one i had spare to try and stop the cabinet pressurising up.

IMG_1903.JPG

Share this post


Link to post
Share on other sites

should have mentioned I have an old vacuum cleaner hooked up to the 'exhaust' outlet, which keeps the visibility good, and probably extends the life of the plastic stuck inside the cabinet lid. Also found 'menu' covers from the stationery store, a cheaper source for the plastic lid protectors, than the real item.

Share this post


Link to post
Share on other sites

I have a bench mounted one with a cyclone device into a 10l pail then out to a wee workshop vacuum. Tbis keeps the lid very well sealed.
I find the garnet it came with breaks down to dust quickly and the gravity feed to the hose suction tends not to work as that is the place i do most of my blasting so I have to rock the cabinet on its sides to shift the medium around. Compressor is 100l with three moisture traps.

I must try the electrolysis one day.

 

Adrian

Share this post


Link to post
Share on other sites

Create an account or sign in to comment

You need to be a member in order to leave a comment

Create an account

Sign up for a new account in our community. It's easy!

Register a new account

Sign in

Already have an account? Sign in here.

Sign In Now

×
×
  • Create New...