Pinball Rehab

pinball repair and restoration

Cleaning and Polishing Plastics Cleaning and Polishing Plastics Hot

For basic cleaning of playfield plastics I use Mean Green, which you can get at Dollar Tree (for a dollar in case you're not good with math).  It's not as good a cleaner as Simple Green, but it's safe on plastics and since I spray it on heavily to flush off dirt and grit, the cheaper the better. 

It's important to flush the grit off of the plastics using a heavy amount of cleaner.  That black stuff is actually very small granules of metal that will scratch the plastic if not washed off before wiping.  Wipe dry with a microfiber towel after cleaning.

Note: Some pinballers clean their plastics in a dishwasher.  This works fine if you have a large quantity to clean, just make sure they can't fall down into the bottom of the dishwasher and the heat cycle is turned off.

If you don't have any scratches in the plastic, follow-up the initial cleaning using Novus 1 and a microfiber towel.  See Image 1 for an example of some plastics from a WIlliams Dracula.  Notice the reflection of the Novus 1 bottle on the long purple plastic on the left side of the image.

If there are scratches in the plastic continue reading.

Image Gallery

Cleaning and Polishing Plastics
Cleaning and Polishing Plastics
Cleaning and Polishing Plastics
Cleaning and Polishing Plastics
Cleaning and Polishing Plastics

Evaluating Scratches

Since the approach you take depends on the scratch depth here's how to quickly check.  If you pull your fingernail across the area and it catches on the scratches you have major scratches.  If your fingernail skips across the scratches, like a record needle skipping, you have medium scratches.  If your fingernail does not catch but you can feel surface irregularities when rubbing a finger across the area you've got minor scratches.

General Polishing/Sanding Guidelines

Always work with a circular motion and don't stay in one spot or you'll create a depression.  You want to replicate the movement of an orbital buffer.  Start with a medium grit (rouge, polish or sandpaper) and then move to a rougher grit if needed.  Move progressively from rougher to finer grits and slightly enlarge the area you are working with each change.

Minor Scratches

For minor scratches use Novus 2 or 3 and a microfiber towel.  Start with Novus 2 and if it's not working give 3 a try.  If you started with 3, move on to Novus 2 once the scratches are pretty much eliminated.  Novus 2 will only remove very minor scratches without a lot of work.

Polish the area with Novus 2 until it is smooth and shiny.  If you're not making much headway go back to the Novus 3.   Do a final polish with Novus 1 and you're done.

See Image 2 for a ramp before cleaning and Image 3 after cleaning with Novus 3, then 2 and then 1.  It took about 5-10 minutes to complete the ramp, which had very heavy ball tracks, and the result is dramatic.

You can also use either of the buffer methods described below.

Medium Scratches

In the case of medium scratches you'll have to start with sandpaper, although it never hurts to give Novus 3 a try first.  Always use a small piece of sandpaper and rather than a sanding block I use my finger to better control the area I'm sanding.

Note: Once you start sanding the plastic will look worse than before you started.  Don't worry it will get better as you progress.

Start out with 400 grit sandpaper and then move to 800 grit and finally 1200 or 1500 grit.  It's impossible to explain when to move to a finer grit, but if you're not seeing visible improvement after a couple of minutes go back to the previous grit.  Once the area looks hazy (like a ball track on a plastic ramp) change over to the Novus products as described above.

I find is slightly easier to use wet/dry sandpaper with water, but either wet or dry will get the job done.

You can also use either of the buffer methods described below.

Major Scratches

The first thing to be aware of with major scratches is that you can easily end up with a divot in the plastic unless you sand a large area and feather out the edges.  Anything more than about a 1/16 inch deep scratch and the area will be noticeably lower after sanding.  Generally you're better off just leaving the scratch alone.

Buffer Method 1

Although a little setup is required this is my preferred method for buffing out minor to medium scratches.  First you'll need a rubber hobby mat or a rubber liner like they use on shower surrounds from Home Depot or Lowe's (see Image 4).  This will keep the plastic from moving around while you're working.

I use a Ryobi 6 Inch Orbital Buffer, but you could use a smaller 3 inch buffer like this one, which would actually work better.  Although not as good a choice as an orbital buffer you could use a buff, or polishing, ball like those from Flitz (see Image 4).  If you're using an orbital buffer use a "light cutting" or "cutting/polishing" foam pad or a wool pad.

I use Meguiar's ultimate compound because I think it works better, but Novus 2 would be fine (Novus 3 if the plastic is heavily scratched).

Clamp the plastic to a bench or table with the rubber mat under the plastic and some wax paper and a block of wood on top of the plastic to protect it from the clamp (see Image 5).  You'll have to work one end, turn the plastic 180 degrees and do the other end.  Make sure the plastic is not moving around on the mat and that no polish gets under the plastic (both will damage the plastic's decal).

You could also use a piece of plywood and some wood screws to mount the plastic.  I would still put the rubber mat underneath to protect the decal.  Also make sure the top of the wood screws are flush with the plastic or you'll tear up your buffer's pad.

Apply your preferred polish and turn the power on.  If you're using a polishing ball be sure and keep it moving in a circular motion.  After a few minutes you should have a nice shiny pinball plastic.

This method is very efficient if you're doing an entire set of plastics.

Buffer Method 2

You can also remove scratches using a buffing wheel on a bench grinder/polisher or a Dremel tool with a buffing/polishing wheel.  With either method be careful since it is easy to create a groove if you polish too long in one spot.  You can also overheat the plastic with this method so make sure your plastic isn't heating up.  Use a white or blue rouge for removing scratches.

This method takes some technique and as mentioned, especially with the Dremel tool, can groove or overheat the plastic.  I don't recommend it for beginners.