The paint on my car door handle was fading and rather than painting it again, I decided to powder coat it for a more durable finish. This will give you the step by step details on how to powder coat any part. I made this at Tech Shop. You can sign up for a Tech Shop here: www.techshop.ws
Teachers! Did you use this instructable in your classroom?
Add a Teacher Note to share how you incorporated it into your lesson.
Step 1: Remove the Old Paint
The first step is to remove the old paint. There are several ways you can do this but I used an 80 grit sandpaper to take the door handle down to the bare metal. It doesn't have to be perfect but you want to get most of it off.
Step 2: Sandblast to Remove the Scratches
After sanding with 80 grit, the part will have a lot of scratches that need to get smoothed out before powder coating. I used a sand blasting cabinet at my local Tech Shop. Be sure to pay extra attention to the edges and crevices. The more time you spend on the prep work, the better your part will look so don't get impatient. You can see the difference the sand blaster makes in the photos.
Step 3: Clean the Part
Now that you've spent all that time preparing the surface, getting it nice and smooth, you'll want to make sure there are no surface impurities that will show up later. Make sure to wear latex gloves for this step as any fingerprints will ruin your part. Clean it once using TSP, rinse it, and then wipe it down with acetone. Make sure the surface is completely clean and dry.
Step 4: Preheat the Part
This step is very important for cast metal parts like mine and I didn't do it. As a result, all my work was for nothing and will have to be redone. Cast metal parts will release gas bubbles as they're heated. If you don't preheat them, these bubbles will show up under your otherwise beautiful powder coat. Put the part in your powder coat oven at the same temperature your powder calls for and let it outgas for a while. The length of time will depend on how much mass your part has. For my part, I should have done this for about 30 minutes and I would have been fine. Don't make the same mistake I did.
Step 5: Spray the Powder
This is the step you've been waiting for. Hang the part using a metal wire and attach your ground. Using about 8-10psi of pressure (I used 10psi because it drops to around 8 when you pull the trigger), spray your part with the powder, making sure to cover it evenly and to get all the edges and crevices. Use enough powder to cover the part but try not to use too much as this will cause wrinkling or orange peel.
Step 6: Cure in an Oven
The final step is to put your part back into the oven to cure. Use the time and temperature recommended by the powder manufacturer. When the time is up, take it out and let it cool. If you've put in the work and taken your time with the prep, it should look great. Mine had bubbles from the outgassing so I'll be doing it again.