Media Blasting

[Photon440]

Has anyone out there heard of or use dry ice blasting? Is it effective, how does it compare pricewise, rust removal, etc. Thanks

I don't know the price, but it's good for delicate surfaces. When the aluminum body on the original Boeing 707 prototype was restored, dry ice blasting was used.

 

[Donny]

This process looks appealing. Not too sure how it will act on rusty crappy metal?

 

[fatecaptured]

Wow. Looks like this may be a good field to get into Donny. I've been looking for a reason to get out of the darn factory. I was wondering if you could p.m. me with the details. Have some prior experience back in the wyotech days.

 

[Donny]

I'm looking at maybe a career change; Non Destructive Testing, not to sure I want to grow Media Blasting unless I have a few workers, a kick *** dust collector about 10 times as big as the one I have now (1800cfm) and we'll see what happens!

 

[jag_mopar]

question

Donny, I just had one door and fender media blasted by a local, I think it was too harsh on the metal. I had visited him previously, looked at a finished job he did on a car, but it seems like the media must have changed or something. What I remember was a smooth surface and what I got was very rough. I grabbed the empty bag from the garbage ato see what he uses and found this. Barton grade 60 HPA, Almandite Garnet. I think he thined the metal too much. I am about to call him.

Your input appreciated

Thanks
JAG

 

[RustyRatRod]

Did I read that right? Are you blasting at 20psi? How does that work?

 

[Donny]

Garnet is a mineral, rather harsh if used straight, and at a high pressure, really good on I Beams, really not so good on sheet metal. Smooth surface is not always ideal. Much of the time these projects go straight to epoxy primer, or self etch (customers preference) and the profile on the metal is always key to getting good adhesion. I would think this Garnet (if used richly) would leave it very rough, workable for sure, usually blasters like to do it fast, sometimes doing it fast isn't the best way. He will likely assume you're challenging him if you call him, this is why I show customers the media I use, and the surface of a product AFTER I media blast it with the same media, then, ask them if this is what they envisioned and expect -- cover all the bases before a problem can arise is what I do, especially when they always bitch about how I must be getting rich charging $150.00 per hour

20psi works fine as long as you have 180 or so CFM backing it up, but, this is the key in this business; C effin' M baby!

 

[jag_mopar]

Thanks Donny, I made sure I visited him several months ago, but I do not remember the finish I received. the parts feel noticebly lighter from when I brought them him. there was no filler in the parts. just thinner now.

 

[Donny]

Filler hides very easily, especially when painted.

 

[jag_mopar]

only tiny dinks in the parts. I know what I gave him. I will be visiting him tomorrow with some other parts if he could tame down the harshness.

 

[Donny]

If you're looking for the 100% smooth metal, 100% plastic is required.

 

[Satellite72]

Ok Donny, I need to pick your brain for a minute if you don't mind. So I finally got off my butt and sent my door to get blasted at a local company. I understood that it would be sand blasted, but when I came to pick it up I was told that they actually Soda Blasted it. I knew that with sand, all I'd have to do is get back home and get it in epoxy, but I wasn't read-up on Soda precedure. They told me how to mix water/vinegar and do the warm-water with dawn cleaning.... what I looked up online confirmed that as well.

Well after the residue cleaning and drying was completed this is what I ended up with.... I did rough up the exterior sheetmetal skin with 100 grit and the DA sander so that my epoxy would adhere. But look at what the rear of the door did!?!.... Is this process supposed to produce Rust? or is that a chemical discoloring? I was hoping to epoxy tomorrow, but I just can't move myself to until someone with more experiance takes a look at the pictures. Any help or direction would be great. Thanks

 

[snakeyes]

for what you had done what did they charge you:eusa_think:

 

[Donny]

That inner door looks like flash rust, I would not paint over it. Soda has its own issues, leaves the metal too smooth, but, flashing like this? Man, good luck! Hope they don't try to tell you that you did something wrong causing it to flash like that! Piss poor places will. And it looks like you have to take that door the rest of the way down for the best results.

 

[Satellite72]

Thats kinda what I was afraid of. I really don't think I did anything wrong in the cleansing process, but I have to admitt... my first thoughts were that any sort of water couldn't be good for bare metal even if with vinegar. I paid $125 to have it done. I've never been to picky about anything really and usually just roll with the puches and work with what I've got, but I wonder if I should run it back over to them?

 

[Cranky]

Did I read that right? Are you blasting at 20psi? How does that work?

Same principal applies here as the HVLP paint system.....? Makes sense to me.

 

[70chargerkrazy]

wow i got alot to learn so when im ready do i blast every thing then start removing problem areas or remove as much as i can then blast before paint decisions decisions i live in new river az you know 2 houses down from the sun ha ha hot and dry

 

[Donny]

70chargerkrazy, huh? What are you asking (me)?

 

[super-bee_ski]

In reale-state it's Location Location Location
In media blasting it's CFM CFM CFM!
I learned THAT from Donny!
"Super-bee_ski"

 

[roadrunnerman]

70chargerkrazy, huh? What are you asking (me)?

Donny, i think he is asking if he should cut out the rust and bad areas he sees then take the part to a blaster or take the part to a media blaster first then cut out what he needs to repair before he puts any primer ao paint on.