Pretreatment and Surface Prep for Powder Coating
Powder coating prep means removing oil, soil and oxides, then applying a conversion coating so the powder bonds and resists corrosion. CPR Systems does both in one step with a hot-water wash (pressures up to 3,000 PSI and temps up to 180 degrees, set to suit the part) that applies iron phosphate or zirconium, then recycles the water to zero discharge.
Why does pretreatment matter for powder coating?
Most powder coating failures (peeling, poor adhesion, early rust) start with poor surface prep. A clean surface plus a conversion coating is what makes the finish last.
- Clean and coat in one step
- Iron phosphate or zirconium
- Zero discharge, closed-loop recycling
Which pretreatment system fits your shop?
- Batch, large or odd-shaped parts: spray wand pretreatment.
- Conveyor line: single-step stage washer (60%+ smaller footprint than a 5-stage).
- Need a booth or containment: custom wash booth.
Powder coating prep checklist
- Remove oils, cutting fluids and shop soil
- Apply a conversion coating (iron phosphate for steel, zirconium for mixed metals)
- Rinse if your process calls for it (city, well or RO water), or use a properly titrated non-rinse system; seal if needed
- Dry fully before powder to prevent outgassing and flash rust
- Test adhesion and coating weight on a regular schedule
Powder coating pretreatment FAQ
Can I just pressure wash before powder coating?
Plain water removes dirt but leaves no conversion coating; adhesion and corrosion resistance suffer.
Is sandblasting enough prep for powder coating?
Usually not. A blasted surface can carry blast residue and has no conversion coating, and blasted parts need extra care to avoid flash rust if they're later washed. Many shops move a large share of parts out of the blast booth and into a spray wand pretreatment booth, which is faster and more economical. That relieves the blast booth bottleneck and saves blasting for parts that truly need it.
What does a pretreatment system cost?
It depends on your part size, volume and setup. Request a quote and we'll size a system to your parts.
How much space do I need?
It depends on your goals. Spray wand systems fit in a wash bay. For conveyor lines, we offer a compact 2-stage system (single-step cleaner-coater plus an optional rinse) that can expand to 3 stages with a seal coat. If you want a more traditional setup, we also build conventional 5-stage washers.
Installation, training, after care
Our pretreatment packages include installation of equipment, training at your facility and after start-up remote support via our online maintenance tracking programs.
Seeing adhesion failures or flash rust?
Send us parts and we'll show you what proper prep does on test panels, at no cost. Call 574-233-9111 or request a free panel test.
Talk to a pretreatment specialist with 35+ years in metal finishing.