Media Blaster with Vacuum

I want to clean up the underside of a car - both frame and body. I did the front half of the car with a 3" wire cup on an angle grinder and a 1" wire cup on an air grinder. These methods work, get the surface rust off and the heavy scale down to mostly bare metal, but are very dusty/dirty and have wires flying everywhere and is tough to get into corners. I'm not looking to do a frame off rotisserie or anything - not looking for perfection, just to see if there's a better way.

The front half of the car was painted with Chassis Saver Aluminum first and then a coat of their Monstaliner bed liner on top of that.

Magnet paints said:

UCP934 Silver-Aluminum - As a pre-primer under gloss or antique-satin black. Heavily filled with over two pounds per gallon of flake aluminum to help smooth and fill pits and deeper rust damage. Incredibly dense yet extremely flexible. Commonly used for marine barge and oil field maintenance. Great for metal roofs, steel truck rims and to rejuvenate tired, rusting chain link fence.

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Car will be on jackstands and can be either inside or outside (was inside for all the wire wheel work last summer) so I'll be underneath on a creeper or on the ground.

Sand (media) blasting does a really good job and I did the radiator support, front bumper support, front inner fenders, etc with a friends outside sand blaster, but that's not a viable option for under the car.

Here's a picture - the metal is solid, just flakey paint and surface rust from sitting outside on the ground. Anywhere there was a heat shield or similar, the paint is intact so I'm not terribly concerned with getting into every nook/cranny between the frame and the body, but was able to do a pretty good job with a spinning 1" wire cup.



Has anyone used one of these sandblasters with a vacuum attached?

https://www.northerntool.com/shop/tools/product_200435367_200435367



Seems to be one model available that everyone resells for about the same price.

Worthwhile?
Junk?
Better options?
What are your thoughts on the best way to prep a body/frame for painting?

Look at that setup on Youtube, I'd think it would be a slow process.

Veeerrrryyy sssllloooww. Great for a small area.

Thanks for the YouTube suggestions - It's not a fast process, but more/less the speed I was expecting having used a "standard" sandblasting cabinet.

I almost wonder if I could rig up a similar vacuum system with the 1" wire cup on a pneumatic die grinder to help keep the dust down. Kind of like they have on the hammer drills now, but using a soft plastic wye and a nylon brush cup that goes over the spinning wire brush....Something like this maybe? Need to make the adapter between the vac brush and the die grinder - will wander around the hardware store tomorrow and see what I can come up with...or maybe go to Northern Tool and see if they have that same vacuum head thing on the media blaster available separately.

Friendly bump for other thoughts/opinions/ideas here. I'll be doing a lot of this in the next month or so.

I have exactly this vacuum blaster. It is a siphon blaster so it requires a lot of volume and pressure, along with very dry media, to work reliably. I used mine to blast centuries of old paint off of wood surfaces in a 300 year old log house we are working on. I used walnut shell media. It worked great and minimized (but did not eliminate) the mess, but my compressor could not keep up so I was constantly waiting for it to pump back up. One big advantage of this blaster is that it collects and recycles the media, so you don't have to stop, scoop up, and refill the media constantly (though you DO have to top it off occasionally). I have not yet tried this with a more aggressive media on rusty metal, but that's the plan. Note that due to the vacuum brush, you cannot see what you are blasting, and the media nozzle always points nearly straight at the work, which is not the best for sheet metal. Also, plan to have to clean the filter frequently.

By the way, lots of vendors sell this ALC blaster. Do a google search. I got mine for somewhat less than what Northern sells them for. Pricing is all over the map.

Here's one that's nearly $200 less than the Northern Tool price. Yes, they are all Chinesium.

Thanks for the feedback - It's also available on Amazon for $469 delivered (FYI). I think Northern Tool has consumables available as well. I can see myself going through a few nozzles and maybe a brush or two.

I've got plenty of compressed air available with a 20HP Quincy 2 stage compressor that runs between 175-200 psi on a 200 gallon tank so that shouldn't be a problem. If I run short, I'll hook up the second one that is currently a spare .

I need to clean the back half of a car underbody/frame so will be on my back on a creeper doing this so am attracted to the vacuum system. Hopefully holding it upside down against the floor will collect most of the "stuff" since gravity is helping it. It seems a bit slow on the videos but might be the only practical option given my constraints.

Thanks again for your feedback on this model - I have not seen any other similar options.

My buddy has one in his body shop. I used it to sandblast some drawers for a toolbox and it worked fine, but it's slow going...

I'll add that ALC wants stupid money for a replacement filter. I found an air filter for a semi truck that is just about exactly the same size and shape for about 1/10 the cost.

When I was working on my car, I seriously considered buying one of those vacuum blasters, but the cost of the filter replacement really influenced me not buy it and the lack of good reviews.

I just used a siphon sand blaster, but what I did was drilled a hole in that vacuum brush you are holding in post #4 and put the nozzle through that hooked the brush up to the vacuum and it worked great.

Another member here worked on my car as well, we had the body on a rotisserie, between him and I we blasted the underneath of the car just using a tractor supply siphon fed blaster and a few bags of their black beauty. time consuming but it was better then doing the wire wheel in my opinion.

joe_padavano said:

I'll add that ALC wants stupid money for a replacement filter. I found an air filter for a semi truck that is just about exactly the same size and shape for about 1/10 the cost.

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Thanks Joe - any details on the filter you used?

casmurbax said:

When I was working on my car, I seriously considered buying one of those vacuum blasters, but the cost of the filter replacement really influenced me not buy it and the lack of good reviews.

I just used a siphon sand blaster, but what I did was drilled a hole in that vacuum brush you are holding in post #4 and put the nozzle through that hooked the brush up to the vacuum and it worked great.

Another member here worked on my car as well, we had the body on a rotisserie, between him and I we blasted the underneath of the car just using a tractor supply siphon fed blaster and a few bags of their black beauty. time consuming but it was better then doing the wire wheel in my opinion.

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That is an interesting idea. So using a regular vacuum, you just empty the media from vacuum back into the sand blaster media bucket and repeat, right? Similar idea, just not a continuous operation like the integrated unit. Wonder if I could put a pickup tube in my vacuum canister for the sand blaster siphon tube and effectively make my own?

Seems pretty straight forward - I'll look into that.

I spent a bit of time on the "Blasting Resource Thread" here on Garage Journal.

What about one of these high volume siphon guns (link below) and using a vacuum brush like shown in post 4 above. I bet I can run the siphon hose inside the vacuum hose and down into the media so then I only have the air hose and the vacuum hose to wrestle with.

Should use standard consumables, be reasonably fast (in comparison) and not horribly expensive? I might need to upgrade my vacuum - it only has an 1-1/2 hose on it so running a 5/8" diameter hose down the middle might not work as well. It's rated for 99 CFM. Maybe just find a bigger hose for it?

https://shop.snapon.com/product/Wet-Dry-Vacuums/Industrial-Wet-Dry-Vacuum/YA1009SSA Don't worry, I didn't pay anywhere near that much for a vacuum cleaner!

Crazy?

https://www.tptools.com/High-Volume-Siphon-Guns-and-Parts.html

I drilled a hole in brush nozzle(post #4) big enough to stick the nozzle through, https://www.tptools.com/S-35-and-C-35-Power-Head-Assembly,293.html using their Medium Ceramic Siphon Nozzles, 1/4" ID, 3 Pk Item# 6310-03MPN# 6310-03UPC# 728044191682 and 5hp wet dry vac with 2 1/2 hose(it was the bigger diameter hose).

I had the media in this, https://www.sears.com/craftsman-50-lb-sandblaster-kit-with-1-4-in/p-00916706000P my compressor puts out 17 17 scfm @ 100 psi.

It worked fine, not woohooo this is awesome but enough to get what I need to be done. You still had some stray sand hitting you, so a face shield would still be wise to use.

Do you have the capability of lifting the body off the frame?

The body is lifted ~2" off the frame and those areas are pretty clean to start with. Not looking for "frame off" restoration here, just to give it a good cleaning and a solid layer of protection. The front half of the car I did with 1" wire brush on a pneumatic die grinder and, while it worked reasonably well, there was a layer of brown dust everywhere, not to mention little wires stuck everywhere too.

I checked the Quincy and it's rated for 70 CFM at 200 psi, so I'm thinking that stepping up to a better vacuum cleaner might be a good idea...Maybe something like this one from Rigid for $160 with 190CFM?

https://www.ridgid.com/pr/en/1250rv-12-gallon-wet-dry-vac

Something like this would be nice, but the $1500+ price tag, not so much...
https://www.boschtools.com/us/en/boschtools-ocs/dust-extractors-gas20-17ah-199175-p/

An update on this. I noodled on how to get the brush and sandblast gun put into an assembly and it finally hit me this weekend (must have been the turkey ).

I bought this skat blast high volume gun from TPTools and a few random 2-1/2" brush accessories from Amazon.

There was a ~12" long 2-1/2" diameter piece of stainless exhaust pipe in the scrap bin at the shop and sure enough it fits over the vacuum hose nice and snug and the brush fits inside as well.

I took this piece and cut it in the middle at a 45 degree angle then drilled a ~5/8" hole in one of the pieces for the blaster head to go through.




The head is held on the trigger handle with a set screw so the plan was to just sandwich the pipe between the two like this. This ended up working well enough for a proof of concept, but not a robust solution. More on that later.



The above placement allowed the siphon tube to run down inside the vacuum hose.





I then took the other half of the exhaust pipe, rotated it and welded it on the first piece as shown.



Then cut the end off to length (as short as I practically could and still fit the brush on).



A couple holes were drilled in the top piece to access the 1/8" set screws so the head could be assembled/disassembled and the nozzle and tip changed as necessary.



The plastic bristle end was cut so it was straight and the exhaust pipe was swaged out so it's a snug press fit.







The whole thing came together pretty well for a couple hours of actual work...





The siphon hose ran down the vacuum hose and into the bottom of an old shop vac. Don't know the CFM rating of it, but it's not enough .





More to come...

Very, VERY slick. Nice work.

Thanks Joe! Hopefully it'll work as slick as it looks .

I mentioned "More to come..." in my last post, so...while the above seemed to basically function ok there were a few problems...

1) The set screw that holds the blast head assembly on the handle and was also asked to hold the vacuum elbow as well, wasn't doing a good job.

The vacuum elbow would be loose/wobbly after just a bit of wiggling around in normal use. It worked well enough to test, but not a long term solution.

First I took a 5/8 bolt, nut and flat washers and made a flat spot around the hole. You can kind of see it in the below picture.



You can also see the dents I put in near the weld by trying to straighten it out in the vice . The nozzle was way off to one side because the hole wasn't drilled quite in the center and my flattening process also wasn't very controlled.

However, this allowed a nice flat area to seat on. The male tip of the handle was just over 5/8" (0.640") diameter so I was able to file it down a bit and ran a 5/8-18 die over it (also not as straight as I'd like) and then be able to use a jam nut to hold the vacuum elbow to the handle assembly as shown below.





This held the vacuum elbow on much more rigidly and allows the blast head to do it's job better as well.

The air orifice is sandwiched between the blast head and the handle assembly with a soft rubber washer, so trying to use this same mechanism to also hold the vacuum elbow would always result in one of the two being loose. To make room for the jam nut, I added a 2nd rubber washer to the air orifice and also trimmed the length of the blast head about 0.160. This puts the set screw on the other side of the flat and still allows a good seal between the blast head, air orifice and handle assembly.





I did test this on a rusty brake rotor. The media I was using is called "Black Blast" which is a coal slag product. It was $7/50lb at the local farm store and better than what I had (nothing ) so I figured I'd give it a shot.



It took a bit to get the media sucked up the 8 foot hose to the gun, but once it did, it had no trouble blasting a ~1/2" wide single pass swath to white metal in just a few seconds.

I mentioned that the vacuum cleaner didn't do a great job of containing the media. It's a well used machine that I just cleaned the filter on, but still don't know if it has much volume.

So, garage journal, I'd like your advice. I've researched vacuum cleaners and come to the conclusion that I don't need lots of suction, but I do want lots of CFM. The media gun calls for 25 CFM @ 80 psi which I'm reasonably sure I have (1/2" full flow regulator, 20HP compressor at 175-200 psi, 500 gallon receiver). With the shop vac shown above, there was quite a bit of "spill" during blasting. It was convenient to be able to just pick it up with the vacuum once you let go of the trigger.

Do I keep whatever one I have above (can't find much for specs on it other than it's a Shop Vac Brand and 5.0HP) for free?

Do I buy one of the below units?
Rigid WD1851 - 172 CFM
Rigid 1250RV - 190 CFM
Shop Vac 92L650C - 195 CFM
VacMaster VJH1612PF 0201

I'm leaning toward the first Ridgid WD1851 since it has a 2.5" hose where as the others use a 1-7/8 hose. I figure since I'm running the siphon hose down the vacuum hose, bigger is better.

Any other vacuums to consider? Can be shop vac style or barrel style, whatever, I'm open to ideas. I'd like to stay in the "few hundred" range, but if there's a superior option that's more money it will be given serious consideration. I've got 220v available if necessary.

Friendly bump for some help on a vacuum recommendation if anyone has any knowledge on the subject...

I can't comment on the vacuum, but thanks for posting this! Looking forward to seeing the finished product and your results!
I do auto restoration/hotrods and could really use a setup like this.

Well - I got a chance to test it out this weekend. It's got it's place for sure, but it's not perfect.

Still need more vacuum volume in my opinion. In the video below the black plate is powder coated, the white table cross bar was painted with Imron and the table top was just sanded bare for reference. Air pressure is set to 50 psi while flowing in an attempt to keep the material from flying around as much. Not sure if it helped much compared to 90 psi. Didn't seem to clean any worse so I left it there.

In general, it does a pretty good job of capturing the fine dust - when I was blasting the upper control arm mount (shown below before and after) the shop didn't get all dusty inside, however there was a layer of larger blast particles on the floor below. Kind of makes sense, the larger particles have more mass and the vacuum can't keep them all contained so they escape. I did need to clean the filter on the vacuum every ~5 minutes of use. Just shake it off and it was better again.

It works surprisingly good upside down so doing the floor of the car won't be too bad I don't think. Very little spillage.

Having a 2nd vacuum would be handy - when you get into outside corners or weird shaped areas like in the pictures, the brush can't "seal" well and there's a lot of blow by. A 2nd vacuum hose would be able to capture this pretty well I think.

All in all, I'm happy with it so far. It cleaned up this difficult to access area of the frame rather well and didn't make a huge mess of the car or in the shop. Cleanup was pretty easy, just use the vacuum to **** up whatever fell on the floor .

I've been in steady search of better vacuum options for this system that I've created.

I've looked at HEPA dust extractors for concrete work and such like these
https://www.protoolreviews.com/buying-guides/best-osha-compliant-dust-extractor-shootout/33792/
which includes models like the below which are all in the 150 CFM/$500 range and include automatic filter cleaning which seems to be a must have feature based on my preliminary testing so far.
Milwaukee 8960-2
Makita VC4710
Bosch VAC090A
Hilti VC150-10 XE
Metabo ASR 35 ACP

I struggled with these due to their small hose size, high price and specs not appreciably better than a high end Rigid/Shop-Vac/Vacmaster unit in terms of CFM and inches of water lift.

So I kept looking and researching...It seems that the cyclonic designs do a pretty good job of separating out the fine particles and prevent the main filter from getting plugged up as fast, but all seem to be geared toward dust collection (high volume, low suction) and generally wouldn't work very well for this particular application. However, I did stumble across this from Dust Deputy which is both high volume and high suction.

https://www.oneida-air.com/dust-col...ll-mobile-14-gal-high-pressure-dust-collector

They use 3) 1300 watt vacuums in parallel for a total of 5 HP, runs off of 220v single phase so they can move a relatively large volume of air (compared to a vacuum) but still have the suction ability for when things get restricted (small hoses, etc). I'm pretty sure this would work just fine with my media blaster, but it is approaching $3k which is a bit staggering... Now, It does have quite a few nice features that go toward justifying the price (filter cleaning, remote start/stop, huge cleanable filter, full sensor/light, etc) but it's a lot overkill for this application in my opinion.

I was thinking though...Could I buy a few of the individual components along with a few low cost "shop vac's" and make my own?

One 5" cyclone separator $280

One 55 gallon drum with removable lid $200. I'm pretty sure I have/can get one of these for free.

4 Vacuums like this - $310 total

A little time and fabrication with the welder and I should be into it for under $800

I think I can stick the dust deputy inside the drum, attach the top of it to the lid and have about 12" below the cyclone device for the media to fall out.

Run the tangent pipe out the side at the top of the barrel and connect this to the hose that goes to the media blaster. Run the media hose to the bottom of the barrel.

Stick a pipe out the top of the lid and connect a bunch of vacuums to it like a Christmas tree. Should move a lot of air?

I'll try and get a sketch of this and post it up in case the above doesn't make sense

Here's a sketch of what I was thinking...

Need/want to figure out a way to "pulse" the filter somehow...

Found this company who makes vacuums with self cleaning filters

https://www.pulsebac.com/index

Anyone used one or have any comments/feedback on them?

Can you blast your car outside? I'm about to blast the underside of my '54 Customline. I live in a residential neighborhood and will be rolling the car out into the street to do the blasting so I need to keep the dust and debris down to a minimum. Don't want to upset the neighbors! I already blasted the front of the frame and front suspension a couple of months ago in my side yard and built these barriers to contain the blasting media.







They worked great! I built them outta 2x4's and 1"x2" strapping then wrapped them with plastic sheeting ($4 for 200 sq ft at Home Depot). Layed down a big HF blue tarp on the ground and every bit of blasting media was contained. The dust floating out of the top was very minimal. I used a Texas Blaster and Black Diamond fine coal slag.



It's a real blaster and does a professional job! Just make sure you cover up really well.

I've done similar (quite a few times, actually) to what Evin did, however in my garage. Built a blast booth out of 2x4s and the same plastic sheeting, though one side (facing the open garage door) has a few of the AC type filters, so I can get air in and out. After I'm done, I let the dust settle, exit, and take off the sheeting and throw it away. No dust in the garage at all! I use the same booth for painting, changing the filters and plastic after each use. Both tasks, I wear a supplier air respirator of some sort.
I wonder if I use the same blaster? I have the Blast Master from Barrel Blaster. They look similar, and are both made in Texas.
SO what's the deal with the whole tool and vacuum combo stuff now? I've always been a Bosch fan, and that's been their big push lately. Is it just so guys can work without wearing a mask? At the least, I always wear the 3M full face respirator with P100 filters. I know it's saving my lungs, but let me tell you, it's saved my face many a times, too! I wouldn't work with out it, even if my tools were vacuuming up junk along the way.

I've thought of trying to do it outside, but I'll likely have as much overall time in it even though the blasting would be quicker for sure. It'll take a full day to get the car out of it's current spot plus moving it back in.

So, I purchased a PulseBak 576 vacuum. It's rated for ~20% more suction and ~100% more CFM than any of the "normal" vacuums or dust collectors on the market along with the self cleaning filters (which should be good for ~1000 hours of use). 100% made in the USA, any repair parts available locally and stocked.

Used the above mentioned media blasting head/gun that I assembled, extended the 2" hose from ~6 feet to ~12 feet (including the siphon hose inside) and went at it. I had to make an adapter to fit the 1-1/2 nominal (1-7/8 actual) port on the vacuum to the 2" hose. Sorry no pictures, will get some next time I'm in the shop.

I bumped the air pressure up from 50 psi to about 70 psi to get it to draw decent media, but once it did, it works really well. Zero dust in the air from the vacuum, minimal dust at the gun which is all dependent on how good of a "seal" you get on the surface you're cleaning. Even with the very brief drops in vacuum to clean the filter every ~10 seconds there isn't really any significant loss of media at the head.

It's a bit loud, but not really much different than the other vacuum and the blaster gun itself isn't quiet so not a big deal. I'm wearing earmuffs anyway . It's really nice not having to clean the filters (ever) and having much more suction/volume available to recover the media. I was able to clean ~10 square feet of underbody in about 5 hours (excluding the frame itself). It's not exceedingly fast, but does a good job, much better than a wire wheel for sure. Short video of a couple passes below - sorry about the aliasing from my LED light.


One thing I noticed during the last hour or so is that it wouldn't draw the media sometimes. When it worked it worked well, but then for some reason it would stop. Maybe it's getting too fine to be drawn up the siphon tube? The media has maybe 7-8 hours on 50 pounds of it? How long does coal slag last, how do you know when it's "done"? I seem to recall discussion of some sort of device on the inlet end of the siphon tube to help it draw the media up? Right now it's just a perpendicular cut 5/8" ID tube stuck in the pile of media in the tank.

I remembered to take a couple pictures when I was in the shop this weekend...

The overall setup


The adapter I made to use the 2" hose I had instead of the 1.5" hose that came with the unit. With the 7/8" siphon hose running through it, I wanted the additional flow area.


What things look like inside


I ended up having more and more trouble with the unit not delivering media to the gun sometimes. I put a slant cut on the end of the siphon hose which really didn't do much.

I think the media is just too "used" and it kind of packs like flour instead of flowing like sand. I took an air gun and stuck it down in the media and slowly pushed some air in and it didn't really do anything, then all of a sudden there was an eruption of sorts and then a decent stream of air once there was a path. I cranked the air pressure to the sandblast gun up from 50 to 75 psi and it helped some, but it was still intermittent. By the time I figured this out, the store was closed so couldn't go buy another bag of media so I'll report back on how it does with new media instead of used. This will also allow me to evaluate new vs used side by side.