Polishing inside clear pens?

What’s it take to clean up the inside of a clear pen?
A LOT of time.  You could make a whole other pen in the time it takes to polish inside a clear section, barrel, and cap.  Am I just really slow?  Or is that really fast?  When I first started making pens it took me even longer, but I’ve sort of gotten the process down, and have a nice little routine.


I use this thing to hold sandpaper like a little flag to sand all the insides of my parts.  I try to start with 600 grit, but sometimes you have to go with a 320 to clean up some ugliness deep inside.  Really sand it out.  Keep it cool and watered down.  You don’t want to cause more problems later.  And don’t press too hard.   Light pressure for the most part.  Sand up to 1500 or 2000 grit before using polish.

I modified this rod.  I used a jeweler’s saw to cut the thin slot on the left to hold sandpaper real tight.

Also – use quality sandpaper and swap out sheets often.   Every part gets new paper.  Use a couple pieces of paper on some parts.  Use it fresh, then when it’s worn, throw it away.  Don’t try to squeeze every penny out of that little piece of sandpaper.  It’s not worth your time.  Fresh paper does a better job.

Once you’ve sanded the inside nearly perfectly with just sandpaper, and you can hold it up to the light and don’t see anymore drill marks, start polishing. Hold it up to light again. Sand some more (probably). Then polish. Then sand again oh my god when will I be done sanding!?!?! Then polish and FINALLY do the final polish with a softer paper towel on a split dowel thing.
I like to use this thing for some of the polishing.
I got it from Tar Heel Parts.
I normally hate talking on the phone, but these guys are great to deal with so give them a call, get a 6″ cartridge rod and a few of the yellow carts.  You an peel some of the cloth back to make them thinner to fit inside certain parts.  They sort of screw on to the end of the rod.  I have blue tape on mine to keep it from leaving black marks inside my parts.
I use the ultra cut with the Tar Heel rod thing, then the ultra finishing polish with the wide slot rod from above, and paper towels.  I like Bounty, but maybe you like blue shop towels better.  It just needs to be soft, and change the paper out often.  As soon as it gets chunky, change it.  Paper towels are cheap.
I get these polishes from Autozone.
It’s gonna take a long time, especially if you’re drilling on a a wood lathe.  You’ll have to sand out ugly drill marks and it can take some TIME.  On a metal lathe you can drill undersize, then use a long boring bar to clean up the heat or burn marks, then do the sanding stuff.
Alumilite is going to be very different than acrylic. It’s softer and takes a lighter touch, so 600 grit at the coarsest, maybe even start with 800 if you can. The problem I used to have was I started with 320 and then I’d spend forever getting my damn sandpaper marks out.  So you might spend a little more time starting with 600 or 800, but less time getting your 320 marks out.


Have fun, and don’t bang your head against the wall too much.  Have a nice bright light to see through your parts at all the ugly scratches you still haven’t gotten out.  Better you see it than the customer and then you have to deal with shipping back to you and working on it again when you were so glad to be done with it, but you really weren’t, so now you have to do it all over again.