Blasting media

[Fred n' Ethel]

Hi Folks.
A basic search didn't help me much.
I have a blast cabinet and one of the import blast pots.
Quite a selection of media out there. Black Diamond, glass beads, sand, soda, ......... and ...
Questions:
What do you typically use, and where ?

Frame, heavy metal components ?
Under body, floor pans, etc.
Outer body panels, the pretty parts.

I have seen mentioned that careful techniques produce great results with minimal/no warpage. Any tips regarding specific procedures ?

Thanks very much,
Fred

[dsraven]

I have an el cheapo deluxe blast cabinet that I use for misc cleaning of parts in the shop. mostly brake mounting hardware as I do mechanical repairs as a sideline to firefighting. I use the regular sil sand for that. if I am doing something of importance or that will be finer I can change to glass beads. I have tried the glass beads but found they turn to powder quickly so for the rough work of regular shop cleaning and rust removal on brakes etc they seemed like a waste. I also have a small pressure pot but haven't used it yet due to weather outside right now and the mess it would make inside my shop if I came inside with it. I was wondering about how to set up the pot but that will become evident when I start blasting I suppose, trial and error.
when doing some industrial style blasting of bodywork over the years, at a do it yourself place, I have found that keeping a good distance, like a couple of feet, moving around a lot and blasting at an angle will remove paint and rust etc but not warp the panels. even on some newer vehicles with thin metal this worked on doors and roofs. thinner metal = further away with the nozzle and move around quicker. on large flat panels this is particularly important. heat can build up fast plus the action of "pushing" with the product. on things like wheels it isn't so important. heat can dissipate quicker into the thicker metal.

[dsraven]

the sil sand can cause problems with paint adhesion due to it's silicone base. it also leaves a profile that will need to be sanded down prior to epoxy primer coating. personally I haven't had the paint adhesion problem although I have sandblasted a few vehicles in my day prior to paint. maybe it is because I have cleaned and sanded so much after the blasting and before the epoxy primer.this is my regimen
pound out the larger dents etc
sandblast
bring inside to warm dry shop
do basic metal bodywork-pound out the big stuff that may be left or found after blasting old bodywork
clean liberally with silicone wax and grease remover and clean rags
sand the area to knock down the blasting profile
spray epoxy primer
do finishing bodywork and any small amounts of filler
spray another coat of epoxy primer to cover any bare metal parts and seal the area
spray primer surfacer and block sand. spray high build, block sand, repeat
the filler should go on over top of epoxy because filler is a porous material and has an affinity for moisture so there should be a barrier between it and the bare steel. it would be best to do a smaller part of the project at a time. that way you can control the time between blasting and epoxy coating. if you have a big project that gets blasted all at once then you could epoxy the whole thing and then do body work and open to bare metal as you do the smaller areas. then epoxy those parts as you finish them
just my method, right or wrong

[Fred n' Ethel]

Thanks for the input, very helpful.
My local store has Black Diamond Coal Slag for single cycle, $8 per bag
Also, Black Diamond Aluminum Oxide for 6-7 cycles, $75 per bag.
Maybe the Al. Oxide would be best for the cabinet, and the coal for outside where I can just let it go after 1 cycle, no need to collect it for reuse.

Thanks again !

[dsraven]

worth a try since it's cheap enough. some guys will lay a tarp down and collect what they can. run it through an old window screen in a frame so you can parse out the chunks.
let us know how it works out.

[b-mac]

First things first, I hate it unless it's the cabinet. Nasty job. Probably took years off my life.

I use the Black Diamond coal slag. I've used sand, but it's more dangerous for your lungs (silica), and it seemed to hold moisture more than the coal, resulting in clogs in the pot blaster, and bad pickup in the cabinet.
I've tried glass bead, but it's for cleaning carbs and other delicate parts. Not aggressive at all.

I also upgraded my blast cabinet gun from the HF one that came with it, to something like this.
https://www.tractorsupply.com/tsc/pr...ndblasting-kit
Works much better. I wonder how long it will last.

The pot blaster has always been a pain in the a$$. I have upgraded the valve and all hoses to larger sizes. I also built a moisture mitigation system with 20 feet of rigid pipe, and valves. Nothing seemed to help the clogging. When I blasted the inside of my cab, I duct taped my saws-all (no blade) to the legs of my blaster pot to keep it constantly shaking. What I pain. Pay to have it done.

[mongocanfly]

the coal slag works very good...the black aluminum costs way to much...ive got one of the cardboard freight pot blasters that works good for small jobs ...the bigger stuff I take to a blast guy....

[Jemezcrusher]

In my experience, the Black Diamond stuff leaves the surface too rough, requiring another sanding. I use glass beads for stuff that will fit in the cabinet, or take it to the pros for the big stuff

[BIGglaSS]

Blasting does NOT CREATE HEAT!!!!!!!!!!!!!

It is the equivalent of beating the tar out of it with a ball peen hammer, stretching the surface, that causes warping. Therefore, lower the air pressure and blast at an angle to strip off paint coatings.

Pot blasting is too messy and a pain in the rear to do at home. Money well spent to drop off my parts at a professional blaster. Only time I use the pot blaster at home is when I have something small that needs to be blasted before welding in a patch panel. Sometimes it is not practical to haul something to the blaster that would only take 2 minutes.

Black beauty is only good for about 2-3 cycles, and is cheap. The blaster I take my stuff to uses aluminum oxide. However, don't let them do it on a flat surface like a roof, door or quarter panel. That gets done with 80 grit D/A sander.

I use black beauty in the pot blaster, and aluminum oxide in the blast cabinet.

[Fred n' Ethel]

Thank you all for the info, very helpful.

I cannot find a blaster near me.
I see on TV folks have a dedicated building with rotisserie's and other fixtures just for blasting.
What is the going rate where you get yours done ?
Are there flat rates ? or is it just estimated, then by the hour ?
Average price for say, a frame ?
Stripped cab ?
Average size car body ?
Ballpark, just for reference.
Thanks

[mongocanfly]

look for somebody that does powdercoating...they will have or know someone who blasts....the guy I use charges by the hour. ...for instance. ..I took my hood, both front fenders ,radiator support, grill and both inner fenders, and tailgate to him...cost was 310
I took the bed , rear fenders and seat frame...cost was 250...that's blasting both sides of each piece, top and bottom...all I've got left is the cab and frame...I'm guessing another couple hunerd for that...
make darn sure whoever you use has experience with blasting body panels. ..what was good can be ruined in a split second.....don't ask how I know.....even experience doesn't mean it can't be messed up...

[Fred n' Ethel]

Hi Greg.
I do have local powder coaters, but they only do the smaller items, mainly bike sized stuff, and don't have any better set-up than me for sand blasting larger pieces.

I'm going to give it a whirl .... what could possibly go wrong ? (famous last words ....)
Thanks.

[mongocanfly]

Fred. ..not sure where your at but I just googled (eastern wv powdercoating) and several popped up....you may have to travel a little...my guy uses coal slag ..that shouldn't be hard to find where you are....

[roger55]

This is how I blast frames. It's an HF pot blaster and I use Black Diamond media.

This one is my '55 Bel Air frame. I just flipped it over so it's about 3/4 done here:



Here's my '57 3200 frame with just a little more needed to finish it off:



Here's the cab bottom after I just finished blasting it:



The Black Diamond leaves a perfect profile for epoxy primer:





I generally do not wholesale blast outer body panels. I strip with a D/A using 80 grit or use a stripping disc on a 4 1/2" angle grinder. Then I blast what the D/A or stripping disc cannot reach or is just impractical to use like the firewall, door jambs and cab interior.

[BIGglaSS]

$225 to have my 57 cab blasted inside/out. I mounted it to a tip dolly so they could get underneath. Highly recommend having it done, they can get into areas that you cant with a D/A.

[Fred n' Ethel]

Great info folks, thanks.

225 seems very reasonable for an cab, inside AND out. That might be a "no brainer" .... depending on the distance.

That dolly looks extremely handy ! Does it enable a single human to flip the cab ? or is a crew required ? Are there any sketches, details on the construction of the dolly(s) ? I have seen the glimpse of others made of lumber (2x4's ? ).

Thanks again guys.

[roger55]

I agree. Blasting is the only way to get it all clean.
It's just not necessary to blast outer panels that can be stripped and cleaned with a D/A or stripping disc.

This is me a couple of weeks ago blasting the perimeter of the hood on my current project:



The top side was stripped using a stripping disc as was most of the car. When I use a stripping disc, I still follow up with a D/A and 80 grit to get the right profile before epoxy primer. Both 80 grit on a D/A and the finish after blasting leave a profile epoxy primer needs.

Here's my current project just finished with the stipping disc:



And here it is after the follow up with the D/A:



I used the stipping disc inside the bed the best I could get and then blasted to finish it up:



Btw, these are the tools I use for stipping:



I buy those stripping discs online in a box of 10.

My blaster is an old HF model. Only mod I made was to remove the lever and stopper and added a 1/4 ball valve behind.



I reclaim my media, and screen it before putting back in. I screen the fresh media too. I usually add about 25% new media to the reclaimed when loading the blaster.

I think to blast everything I needed to blast on my pickup including the frame, I used 7 or 8 bags of $8 per bag Black Diamond. Very cheap. As far as those stripping discs, with care by not using the edges much, a box of 10 should strip an entire vehicle. I get them from Roark Supply. They have the best price.

So yes, I can do this on the cheap. The labor isn't too bad but I won't blast in the Texas summer heat so I schedule my projects as not to need to do that.
The key is have the space to do it and a large enough air compressor to run a blaster.

[mongocanfly]

fred...there was a guy on the 67-72 side that had plans for a cab dolly that would let you flip it front to back and side to side.....

[mongocanfly]

here it is....tip and flip......http://67-72chevytrucks.com/vboard/s...d.php?t=192185

[roger55]

Originally Posted by mongocanfly

fred...there was a guy on the 67-72 side that had plans for a cab dolly that would let you flip it front to back and side to side.....

I dealt with that issue by having both a dolly and a table with wheels.
I just roll the cab off the dolly onto the table. Need 1 helper is all.

My good friend and neighbor (clay54 on this site) made this dolly for me:



The table was something my wife put together for moving plants inside the garage in the winter. I temporarily pilfered it and added the wheels:



Cab rolled on it's back on the table cutting all the rusted areas out: