Anytime you’re coating a part whether it is a paint, powder, or plating you need to start with an ultra clean surface that the coating can adhere to. Liquid paints can be very particular about the cleanliness of the surface and it is best to get everything surgically clean. Powder Coating isn’t quite as bad but it does need clean surfaces to apply and cure powder over. The hard part about powder coating is that it is an extremely durable coating and when an issue arises it is usually after the powder has cured and it is difficult to remove. For this reason it is best to take precautions to assure your part is as clean as possible before coating. Below are a few cleaning techniques we suggest to use.
1: Mechanical Removal
If your part is coating in heavy grease, rust, or dirt, you will want to start by cleaning the part with some good old fashioned elbow grease. Grab a stainless wire brush or chuck a cylindrical wire brush up in your drill and quickly knock any loose or debris off of the item to be coated. Even if you have a media blaster this should be your first step to save wasting media or contaminating media in a cabinet.
2: Chemical Stripping
When you’re dealing with old or vintage parts you will find that most have been painted or coated numerous times and it can be REALLY time consuming to mechanically remove the coatings and some methods may only melt the old paint and cause a bigger mess than you started with. Using a quality chemical paint stripper like Eastwood Down To Metal Paint and Powder Stripper will allow you to save time and energy. Chemical stripping works on its own with no real labour to strip old coatings and allows you to multi-task and work on other parts of the project at the same time. Most coatings will strip down to bare metal in one coat of down to metal stripper and you can just wash the parts and clean with Eastwood PRE or Afterblast to get the parts back to fresh, clean metal.
3: Abrasive Blasting:
The most aggressive way to remove paint or powder and prepare parts is to use an abrasive media blaster. Media blasters combine a high pressure air from an air compressor and mix it with the media of your choice to blow coatings away from the surface. Powder coating also adheres best to a surface with some texture to it so an aggressive media can be used to blast the surface of a part and leave a clean part with enough texture the powder can bite in and hold. Blasters range from small job kits that don’t require a large air compressor or a lot of time to set up to blast cabinets to keep the media contained (great for small parts), and large pressure pot style blasters that you can do an entire chassis or body with. The pressure blasters do require a large compressor, but they will work the quickest on larger parts like wheels, frames, bodies, and suspension parts. Make sure you carefully look at the requirements of the blaster before purchasing so you can best match it with your pre-existing air compressor. After blasting make sure you clean all of the blasting residue off with Afterblast.
4: Parts Washer
A parts washer is good for initial clean up of a part you’re coating. It can help soak the part to remove grease and will also keep the mess contained from cleaning the parts. We offer multiple sizes of parts cleaners from bench top to stand alone washers.
5: PRE Paint Prep
PRE Paint Prep is the final step for cleaning a part before powder coating. At this point I like to wear a pair of nitrile gloves and spray the part down with PRE really well. I then use a clean, lint-free rag to wipe the part down to take any excess dirt, grease, or residue off the part. A clean part can still hold grease or dirt from just handling it and thus the need for gloves when handling the part before coating.