TheSamba.com :: View topic - Interesting- pressure washer sandblasting

Sun Sep 17, 2017 9:55 am

I am sure that somewhere this has been explored before in this forum....BUT...I think this would be ideal for someone like me.

Don't get bored with the opening. You can skip to about 1:21 if you want

https://www.youtube.com/watch?v=mYtbPG1RKgY

I will probably not be restoring any other cars other than the one I have now. Its a 15 year project as it is. I need limited sand blasting. Its not the type of project that I can get done all at once or entrust to the average blasting shop.

With a full unibody and too many parts that are just not made....there are things that cannot be removed to get to some of the areas I need.

Then there is the issue of needing a large compressor....a good one....and 230V hook up. Outside of sandblasting or painting cars I would have no use for a compressor that large after I have done what I need. BUT....I could use a good sized pressure washer later as well.
And then there is the dust control.....and the generated heat from sand or media blasting.

So for doing segments....this looks like pretty good option.

Ray

Sun Sep 17, 2017 12:18 pm

I would be very cautious using this. You will warp the shit out of all the panels using sand. Maybe try crushed glass like they're using in the dustless blasters.

Sun Sep 17, 2017 2:14 pm

I have heard of brick houses being pressure washed with a sand mixture to prep them before painting. I tried this on a body panel with a siphon sand blaster and it did work okay. You would need a device to keep the sand suspended in the water for a 'go to method'.

Sun Sep 17, 2017 3:04 pm

RLFD213 wrote: I would be very cautious using this. You will warp the shit out of all the panels using sand. Maybe try crushed glass like they're using in the dustless blasters.

Understand.....its sand mixed with water. There ia no heat ...and no toxix silica dust to speak of. Thats the whole point of this unit. Its not just a siphon gun. Its using high pressure water.

Ray

Sun Sep 17, 2017 5:19 pm

theKbStockpiler wrote: I have heard of brick houses being pressure washed with a sand mixture to prep them before painting. I tried this on a body panel with a siphon sand blaster and it did work okay. You would need a device to keep the sand suspended in the water for a 'go to method'.

It shouldn't be problem I dont think. The sand and water exit the same nozzle at the same time.

I used to work for a chemical company and installed qnd serviced high end industrial pressure washers as part of my equipment line. 16 horse belt driven triplex pumps with 3500 psi at 5 gpm constant.

The thing ai can almost tell you for sure watching that video....is that even though that pump is "rated" at 4200 psi.....its most probably running at qbout 2500-2800 pai...certainly no more than 3000 psi. Its max output of 4gpm.....is NOT at 4200 psi. No pumps are rated like that.

The higher the pressure restriction....the lower the volume throuput. Typifally most good pumps like that have their max flow rating .....with useful pressure down around 1500-1800 psi.

And.....you will need flow VOLUME of water through the nozzle to create suction to move sand.
I would think on a sheet metal panel...similar in rigidity to what we use high pressure washers for in my industry.....you would probaboy want to work at a 60° angle or lower so as not to "push" against the panel. Ray

Wed Sep 20, 2017 7:38 pm

I've been looking at these too. As you note, volume seems to be the key. I haven't found any so far that require less than 3.5 gpm.

Fri Sep 22, 2017 7:57 am

DHVW wrote: I've been looking at these too. As you note, volume seems to be the key. I haven't found any so far that require less than 3.5 gpm.

Yes....from what I am seeing...If you dig around on Youtube with "Pressure washer sandblasting"...you will find that numerous companies make siphons and kits...not just DeWalt.

More than one has noted that around 4.0 gpm and 3500-4000 psi is kind of the happy medium as you get high flow and decent abrasion. The next higher stage up will have to have 4500-5000 psi and can then get away with about 3.5 gpm....which is pretty much what you have to get away with because unless you have a MONSTER industrial pressure washer....the average medium to high end pressure washer that can make 5000 psi....will naturally reduce its gpm flow when you throttle it up. Ray

Sat Oct 07, 2017 1:04 pm

I did this with a kit from Northern Tool:

http://www.northerntool.com/shop/tools/product_200660204_200660204

Works great with some modifications. I made my own hopper out of a plastic 55 gallon drum. I used glass media. The brass tip wears out and it's about $30 to replace. I went through two tips doing the chassis.

Used with a Ryobi pressure washer.
Works well. Didn't warp the floor pans. But I did not try it on the body so I don't know if it would warp them since they are made of a thinner metal.
Sprayed it with phosphoric acid afterwards to prevent from rusting.

Sat Nov 18, 2017 8:59 pm

raygreenwood wrote: I am sure that somewhere this has been explored before in this forum....BUT...I think this would be ideal for someone like me.

Don't get bored with the opening. You can skip to about 1:21 if you want

https://www.youtube.com/watch?v=mYtbPG1RKgY

I will probably not be restoring any other cars other than the one I have now. Its a 15 year project as it is. I need limited sand blasting. Its not the type of project that I can get done all at once or entrust to the average blasting shop.

With a full unibody and too many parts that are just not made....there are things that cannot be removed to get to some of the areas I need.

Then there is the issue of needing a large compressor....a good one....and 230V hook up. Outside of sandblasting or painting cars I would have no use for a compressor that large after I have done what I need. BUT....I could use a good sized pressure washer later as well.
And then there is the dust control.....and the generated heat from sand or media blasting.

So for doing segments....this looks like pretty good option.

Ray You do know that an alternative to a larger compressor would be a gas powered "contractor" compressor unit. A friend of mine bought 1 and used it for everything air powered. It worked great for painting too, not to mention using it for it's original purpose... an air nailer. He would take it to the track to air his tires back up after making a few passes, and it was great for rescuing cars out of peoples back yards. He ended up selling it for almost what he paid for it when he moved, as he didn't want to haul it, and needed the extra money for the new place. Just a thought. Another thought would be renting a big mobile air compressor (1/2 a V8 ). There's plenty of those that can be had for a day or 2 at a time.

Sat Nov 18, 2017 9:42 pm

Bobnotch wrote: raygreenwood wrote: I am sure that somewhere this has been explored before in this forum....BUT...I think this would be ideal for someone like me.

Don't get bored with the opening. You can skip to about 1:21 if you want

https://www.youtube.com/watch?v=mYtbPG1RKgY

I will probably not be restoring any other cars other than the one I have now. Its a 15 year project as it is. I need limited sand blasting. Its not the type of project that I can get done all at once or entrust to the average blasting shop.

With a full unibody and too many parts that are just not made....there are things that cannot be removed to get to some of the areas I need.

Then there is the issue of needing a large compressor....a good one....and 230V hook up. Outside of sandblasting or painting cars I would have no use for a compressor that large after I have done what I need. BUT....I could use a good sized pressure washer later as well.
And then there is the dust control.....and the generated heat from sand or media blasting.

So for doing segments....this looks like pretty good option.

Ray You do know that an alternative to a larger compressor would be a gas powered "contractor" compressor unit. A friend of mine bought 1 and used it for everything air powered. It worked great for painting too, not to mention using it for it's original purpose... an air nailer. He would take it to the track to air his tires back up after making a few passes, and it was great for rescuing cars out of peoples back yards. He ended up selling it for almost what he paid for it when he moved, as he didn't want to haul it, and needed the extra money for the new place. Just a thought. Another thought would be renting a big mobile air compressor (1/2 a V8 ). There's plenty of those that can be had for a day or 2 at a time.

Sure...but that is still sandblasting or media blasting.

Its too easy to wreck something with sandhlasting especially on q car like mine with long quater panels.

I have since spoken to numerous people who have used water/sand blasting. While a lite slower than sand on some things....its faster on others. And....it does not get hot ....though you do have ro be careful of angles on thib long panels. A atraight on shot can,start the panel vibrating.....and flexing because tne water and sand has so much mass.

And then there is the dust issue with sandblasting.

Hard to say at this point. It will probably be a rental either way because once I am done iwth tue tasks at hand I have no use for either a massive compressor or pressure washer. Ray

Mon Nov 20, 2017 10:54 am

raygreenwood wrote: Bobnotch wrote: raygreenwood wrote: I am sure that somewhere this has been explored before in this forum....BUT...I think this would be ideal for someone like me.

Don't get bored with the opening. You can skip to about 1:21 if you want

https://www.youtube.com/watch?v=mYtbPG1RKgY

I will probably not be restoring any other cars other than the one I have now. Its a 15 year project as it is. I need limited sand blasting. Its not the type of project that I can get done all at once or entrust to the average blasting shop.

With a full unibody and too many parts that are just not made....there are things that cannot be removed to get to some of the areas I need.

Then there is the issue of needing a large compressor....a good one....and 230V hook up. Outside of sandblasting or painting cars I would have no use for a compressor that large after I have done what I need. BUT....I could use a good sized pressure washer later as well.
And then there is the dust control.....and the generated heat from sand or media blasting.

So for doing segments....this looks like pretty good option.

Ray You do know that an alternative to a larger compressor would be a gas powered "contractor" compressor unit. A friend of mine bought 1 and used it for everything air powered. It worked great for painting too, not to mention using it for it's original purpose... an air nailer. He would take it to the track to air his tires back up after making a few passes, and it was great for rescuing cars out of peoples back yards. He ended up selling it for almost what he paid for it when he moved, as he didn't want to haul it, and needed the extra money for the new place. Just a thought. Another thought would be renting a big mobile air compressor (1/2 a V8 ). There's plenty of those that can be had for a day or 2 at a time.

Sure...but that is still sandblasting or media blasting.

Its too easy to wreck something with sandhlasting especially on q car like mine with long quater panels.

I have since spoken to numerous people who have used water/sand blasting. While a lite slower than sand on some things....its faster on others. And....it does not get hot ....though you do have ro be careful of angles on thib long panels. A atraight on shot can,start the panel vibrating.....and flexing because tne water and sand has so much mass.

And then there is the dust issue with sandblasting.

Hard to say at this point. It will probably be a rental either way because once I am done iwth tue tasks at hand I have no use for either a massive compressor or pressure washer. Ray

I was checking out the links for "water-sand blasting" and it looked promising. However it also looked like a summer job, as I sure wouldn't want to do that in winter. As it is with regular sand/media blasting, it can be done almost any time of year.
I guess the big question is, how much do you really want blasted (stripped)? If it's the whole outer shell, then going with a "dustless" company might be the way to go. Just have to figure the cost versus time deal. I mean there was a video of the guy who stripped a 64 Impala in an hour using a dustless company, and there were other vids that people seemed to take hours doing part of a vehicle (some with the 50 lb bag of sand lasting a whole 10 minutes).
Having done my fair share of sand blasting, I know personally that I really don't care for it, but I do like the end result for working off it (bare metal). I might look into hydro blasting, but that'll be down the road, and not until spring at the earliest.

Mon Nov 20, 2017 7:04 pm

A word of advise. I just recently had my 1966 beetle body dustless blasted and the company severely warped my doors to the point of needing replacements. The warping isn't done by heat alone, but also the effect of peening and expanding one side of panel only. be very careful or you'll be replacing warped sheet metal.
By the way if your in Las Vegas don't use Cleanworks Dustless Media Blasting unless you need your panels destroyed without accepting responsibility.

Mon Nov 20, 2017 7:22 pm

I had my bug done with the pressurized water and glass flakes....1 hour bug totally stripped inside and out.....water has a rust preventer mixed...car was worked on for 3 months prior to 1st coat of primer....not 1 spec of surface rust...and NOT 1 warped panel....well worth the $$ IMO

they came to house, did the job and an hr later they were leaving....best $$ ive spent on auto prep in a longgg longgg time

Tue Nov 21, 2017 3:59 pm

air-h2o-air wrote: I had my bug done with the pressurized water and glass flakes....1 hour bug totally stripped inside and out.....water has a rust preventer mixed...car was worked on for 3 months prior to 1st coat of primer....not 1 spec of surface rust...and NOT 1 warped panel....well worth the $$ IMO

they came to house, did the job and an hr later they were leaving....best $$ ive spent on auto prep in a longgg longgg time

What is the company you used?

Wed Nov 22, 2017 12:37 pm

Local guy that had the equipment.....they always advertise on Sunday morning car channels.....the equipment used is called dustless blasting