Thermal spray/spray welding/metalizing resources for artwork?

Hi guys,

Unusual question I'm sure but after considerable research I can't find a lot of information. I know what metalizing is used for normally so I figured I'd ask in here.

I make artwork and weapons and similar things out of metal, steel mostly. I have some ideas for using a thermal spray gun to do some interesting effects and/or for rust prevention when things like paint/powdercoat are not a desired option. However, I cannot find any good information on brands, models, how-to guides, buying guides, nothing. Even on youtube the only related info was from guys like Abom79 who just show the process (for machining) and that's it.

Anyone have any good resources that I might be able to dive into? I'm looking to buy a cheap used setup (Metco seems to be the most popular) on ebay or CL and use some different powders to experiment with my artwork. I just don't want to drop $1k on a used setup when I have no idea what else I'd need, how to use it, dangers to avoid, you name it. I do have an O/A setup and an air compressor so I believe I have the components I need. Weird in this day and age when I can't find something like that, must be a somewhat obscure art or perhaps only confined to the big boys who aren't exactly making youtube videos or how-to guides?

Thanks,
Dope

What exactly are you trying to do? There are several categories of spraying: Flame spray that is low speed which melts the powder/wire (or almost melts), HVOF which sprays the powder/wire at high speed - faster than Mach 1, and plasma which is probably not interesting for you.

Thermal spraying is good at low melting point metals like zinc and pre-applying hardfacing that is later heated to melt the binder. For higher melting point metals the adhesion to the base metal is a mechanical bond and the coating is likely to flake off if the sub straight flexes.

Dangers are similar to welding - but with much more fumes. The couple of times I saw it done in person the operators were wearing full respirator masks and ear muffs. HVOF is like having a small jet engine in your hand.

I know an artist who does a fair amount of metal spraying. He, like everybody else I know who has tried it, says "cheap" and metalspraying do not go together in the same sentence.
Its an expensive process, and your results with a 50 year old used rig will most likely be unsatisfactory.
Usually, in industry, the spray deposition is machined off again- so they dont care about cosmetic appearance, just good bonded metal buildup- hence there is virtually no industry info about getting a good cosmetic finish.
As I recall, the artist I knew was using a rig that cost several thousand dollars, a wire feed deposition system, and the wire itself was quite expensive, too.
He had to basically invent his own techniques, and spent several years perfecting it.

Can you do it?
Sure.
But it wont be cheap, and you will have to experiment a lot.

A metal powder metallizing torch might be of use. I have a UTP torch system.

In real world usage, there is a lot of concern about prepping the surface so the coating will adhere. This may not be an issue for art work where likely nothing will be banging against the deposit that might loosen it up. But generally, sand blasting would be the initial prep if the part cannot be rough machined.

The 'looks' of a sprayed deposit is not particularly pretty unless it is machined. It looks like a medium grit sandpaper. It doesn't flow and fill at all, it is just a bunch of particles globbing onto each other.

The part you are metallizing also has to stand up to considerable heat, so that may restrict your base materials.

I can also spray a polyetheylene powder with my torch. These powders are available in various colors. Application might be compared to spray painting as these do actually melt and flow a slight bit and you can't dwell anywhere with the torch for fear of starting the deposit on fire. The result is comparable to powder coated metal, the adhesion is strong.

I have a Metco 5P oxy/fuel powder setup with a lot of supplies that I've been meaning to put on ebay if you are interested, and I can help you get started. I bought it new and did metallizing part repair as a service for a while. I did a little coating, I sprayed aluminum on car headers and sprayed thermal coatings on piston domes, but that didn't become productive because there were soon better ways of doing both things. Once you have a setup like this all it costs is powder and gases, but the powder is expensive by the pound. There are rust resistant materials like aluminum (sprayed with hydrogen as fuel), stainless, nickel, etc but the main focus of the manufacturer seemed to be machine repair. A cheaper system materials-wise is a wire fed system, but it's much bulkier and there's fewer materials available in wire than in powder.

HuFlungDung said:

I can also spray a polyetheylene powder with my torch. These powders are available in various colors. Application might be compared to spray painting as these do actually melt and flow a slight bit and you can't dwell anywhere with the torch for fear of starting the deposit on fire. The result is comparable to powder coated metal, the adhesion is strong.

Click to expand...

That's got to hurt like all get out when you get it on your fingers....OUCH !

Dave G. said:

What exactly are you trying to do? There are several categories of spraying: Flame spray that is low speed which melts the powder/wire (or almost melts), HVOF which sprays the powder/wire at high speed - faster than Mach 1, and plasma which is probably not interesting for you.

Thermal spraying is good at low melting point metals like zinc and pre-applying hardfacing that is later heated to melt the binder. For higher melting point metals the adhesion to the base metal is a mechanical bond and the coating is likely to flake off if the sub straight flexes.

Dangers are similar to welding - but with much more fumes. The couple of times I saw it done in person the operators were wearing full respirator masks and ear muffs. HVOF is like having a small jet engine in your hand.

Click to expand...

Thanks for the info. I'd almost certainly be looking at a flame spray and probably powder due to the variety available and the relatively cheap price. This would be all artistic purposes so I'd probably be trying to use things like bronze/aluminum/zinc most likely. Hardness and damage resistance and machinability and all that is totally secondary. Producing some unique looks and finishes on my artwork is the only goal, as long as it literally doesn't just fall off by itself. Underlying material will almost always be plain old mild steel I'd say.

Ries said:

I know an artist who does a fair amount of metal spraying. He, like everybody else I know who has tried it, says "cheap" and metalspraying do not go together in the same sentence.
Its an expensive process, and your results with a 50 year old used rig will most likely be unsatisfactory.
Usually, in industry, the spray deposition is machined off again- so they dont care about cosmetic appearance, just good bonded metal buildup- hence there is virtually no industry info about getting a good cosmetic finish.
As I recall, the artist I knew was using a rig that cost several thousand dollars, a wire feed deposition system, and the wire itself was quite expensive, too.
He had to basically invent his own techniques, and spent several years perfecting it.

Can you do it?
Sure.
But it wont be cheap, and you will have to experiment a lot.

Click to expand...

I don't mind the experimentation but unfortunately I don't have thousands as I'm just a solo hobbyist artist who doesn't even break even on his sales at this point. Thanks for posting, definitely something to consider. Does the artist you knew have any sort of social media accounts or galleries or anything? I'd be curious to see his work, I previously had never heard of anyone using such a technique.

HuFlungDung said:

A metal powder metallizing torch might be of use. I have a UTP torch system.

In real world usage, there is a lot of concern about prepping the surface so the coating will adhere. This may not be an issue for art work where likely nothing will be banging against the deposit that might loosen it up. But generally, sand blasting would be the initial prep if the part cannot be rough machined.

The 'looks' of a sprayed deposit is not particularly pretty unless it is machined. It looks like a medium grit sandpaper. It doesn't flow and fill at all, it is just a bunch of particles globbing onto each other.

The part you are metallizing also has to stand up to considerable heat, so that may restrict your base materials.

I can also spray a polyetheylene powder with my torch. These powders are available in various colors. Application might be compared to spray painting as these do actually melt and flow a slight bit and you can't dwell anywhere with the torch for fear of starting the deposit on fire. The result is comparable to powder coated metal, the adhesion is strong.

Click to expand...

Good to know. I have a sandblaster and a lot of my artwork ends up with a very rough surface finish at some stage anyway (usually sanded with 16 or 24 grit). Especially good to know about the surface finish, I was hoping for something at least somewhat smooth and self-filling/leveling. Something that looks like sandpaper isn't that great. The polyetheylene powder does sound right up my alley however. How much does a rig like yours cost ballpark? Just curious.

Mud said:

I have a Metco 5P oxy/fuel powder setup with a lot of supplies that I've been meaning to put on ebay if you are interested, and I can help you get started. I bought it new and did metallizing part repair as a service for a while. I did a little coating, I sprayed aluminum on car headers and sprayed thermal coatings on piston domes, but that didn't become productive because there were soon better ways of doing both things. Once you have a setup like this all it costs is powder and gases, but the powder is expensive by the pound. There are rust resistant materials like aluminum (sprayed with hydrogen as fuel), stainless, nickel, etc but the main focus of the manufacturer seemed to be machine repair. A cheaper system materials-wise is a wire fed system, but it's much bulkier and there's fewer materials available in wire than in powder.

Click to expand...

Yeah that's the dilemma that I've been seeing. Is the applied surface finish of wire fed vs powder systems any different? Do you just use normal O/A tanks and fittings or is there some sort of middleman setup to mate them together? Or am I way off on even assuming that I'd be able to use my normal O/A tanks/regulators and such?

Dope

Is the applied surface finish of wire fed vs powder systems any different?

Click to expand...

Not that I've ever seen. The wire is melted and sprayed the same way the powder is melted and sprayed and produces the same surface. Higher tech application methods can produce harder coatings, electric arc and plasma systems can apply more durable thermal barriers and harder wear surfaces than fuel gas systems.

Do you just use normal O/A tanks and fittings or is there some sort of middleman setup to mate them together? Or am I way off on even assuming that I'd be able to use my normal O/A tanks/regulators and such?

Click to expand...

The tanks and regulators and standard. My Metco setup uses flowmeters between the regulators and the gun to control the flame adjustment. The gun has an on/off valve, and you set the flowmeter according to published parameters for the material you are spraying. I believe this is to take the subjective flame adjustment out of the hands of the operator. Some materials use alternative fuels, like the pure aluminum using hydrogen for fuel.

found his site- he is a nice guy, he would probably answer questions.
Maiden Metals Foundry
and other metal workings

Mud said:

Not that I've ever seen. The wire is melted and sprayed the same way the powder is melted and sprayed and produces the same surface. Higher tech application methods can produce harder coatings, electric arc and plasma systems can apply more durable thermal barriers and harder wear surfaces than fuel gas systems.



The tanks and regulators and standard. My Metco setup uses flowmeters between the regulators and the gun to control the flame adjustment. The gun has an on/off valve, and you set the flowmeter according to published parameters for the material you are spraying. I believe this is to take the subjective flame adjustment out of the hands of the operator. Some materials use alternative fuels, like the pure aluminum using hydrogen for fuel.

Click to expand...

Thanks. If you do decide to sell your setup (at poverty prices ) let me know, or at least send me the ebay link if that's the direction you go in. Much appreciated!

Ries said:

found his site- he is a nice guy, he would probably answer questions.
Maiden Metals Foundry
and other metal workings

Click to expand...

Wow, thank you! I'm gonna drop him a line.

Dope

It's for sale now, I'll take $2K for it and there's probably that much in powder with it.

Hey Dope,
Not sure if you figured the thermal spray thing out, but I own a thermal spray shop in Eastern Mass. falmer.com Feel free to give me a call if we can be of help.

Dope said:

This would be all artistic purposes so I'd probably be trying to use things like bronze/aluminum/zinc most likely.Dope

Click to expand...

If you want to play with zinc get a can of galv-viz. It is a 1/4" square stick of zinc that you warm the part with a torch and rub onto the metal. It is used to add galvanzing to a weld done on galvanized parts. If you are quick with it after you make the weld, wire brush weld and rub on the zinc stick and smear it arround with a hand wire brush. Have to be quick before the weld cools or you come back later with torch to heat it up. It is hard to see the galv has been "repaired" if done right.

May be a little on the expensive side, but these guys arguably have the best cold spray setup if your bond is critical.
Speed Spray Metals