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Another pic of the end result---What do ya think????

How much was it? Looks pretty good to me.

Is it possible to powdwecoat over existing powdercoating? O does the piece need to be sandblasted then prime and powdercoat?

Powder will stick to its self. Not sure exactly how it works though.
I know it can be touched up, and am told it blends well.
What I wander about is if the existing powder would take continuous coats.
One of the great things about powder coating is the uniform coverage.
I was under the impression that this was achieved because the charged
metal part would attract a finite thickness of powder and once that was
achieved, no more powder would be held.

The last time I had some stuff coated, the guy showed my some stuff that had
a candy finish, which used a chrome powder base and an additional translucent
powder candy over the top. I don't know how many coats can be built up though.

Did a little Google action, there are 2 types of powders.
Thermosetting and thermoplastic.
The thermoplastic will re melt when heated, thermoset will not.
Interesting.

chargerandpowerwagon wrote:Is it possible to powdercoat over existing powder coating? O does the piece need to be sandblasted then prime and powdercoat?

It is possible to coat over existing powder coating, however it is always best to blast to bare steel, zinc-rich powder prime (or use zinc/iron phosphate pretreatment), and then apply your color/topcoat.
Any competent Powder coating shop would strongly recommend this over just sanding and re-coating, as they have no way to tell how good the adhesion between the first coat and the steel is. Also, when applying multiple coats of powder, the lower coat should only be partially cured so that the top coat can chemically bind to the lower coat.

As for any special effect and multiple coat applications, the variety and selection out there is enough to make your head spin.

nfury8 wrote:Powder will stick to its self. Not sure exactly how it works though.
I know it can be touched up, and am told it blends well.
What I wander about is if the existing powder would take continuous coats.
One of the great things about powder coating is the uniform coverage.
I was under the impression that this was achieved because the charged
metal part would attract a finite thickness of powder and once that was
achieved, no more powder would be held.

The last time I had some stuff coated, the guy showed my some stuff that had
a candy finish, which used a chrome powder base and an additional translucent
powder candy over the top. I don't know how many coats can be built up though.

Did a little Google action, there are 2 types of powders.
Thermosetting and thermoplastic.
The thermoplastic will re melt when heated, thermoset will not.
Interesting.

The powder is what gets charged and the part is grounded.

Once you go past 2 coats, the insulating effect of the powder coating starts to affect the way the powder sticks to the part and you'll start to have problems with uneven film build and cratering (think big ugly fisheyes). powder can be applied to various thicknesses, and can definitely be put on too heavy, causing runs and sags during the cure cycle.
(I've trained rookie coaters who did horrendous things with powder guns)

The variety of powders include Polyesters, Urethanes, Hybrids, Acrylic Hybrids and Epoxies, all of which fall in the thermosetting category. Most of the automotive aftermarket coatings you'll encounter will be polyester powder. I have little experience with Thermoplastic powders apart from some nylon powders.