Keithley 2015 Benchtop DMM Display Polish

[2bluesc]

Hey all,

I purchased the infamous Keithley 2015 from eBay for standard DMM duty and some audio projects.  It showed up in good electrical shape and has calibration stickers on it from 2014 and 2015 and agrees with my other test equipment, so that's good.  But, the plastic display was quite scratched and difficult to read the VFD behind it.  I had   heard of a number of people replacing the VFD, but I didn't think mine was that dim and thought some polish might help.

Figured this is pretty generic process and anyone with a tired looking DMM could follow similar steps.  Except of course those with proper glass displays that don't get scratched by just looking at them... but hey, it's only a $4k DMM. 

After some disassembly I restored it in a few steps:

• Mask off the edge of the display, Keithley Logo, and Model text to avoid removal during sanding
• Wet sand the display flat with 2000 grit sandpaper and a Dura-Block AF4400 I cut down to size to get the deep scratches out and while keeping the display flat and not wavy
• NOVUS 3 Heavy Plastic Heavy Scratch Remover
• NOVUS 2 Heavy Plastic Fine Scratch Remover
• NOVUS 1 Plastic Clean and Shine
• Back to work!

When you're done with the Dura-Block AF4400 makes an ok DMM stand to prop it up for easier reading since almost none of these have the original handle anymore.

The display is hard to photograph because it either looks bad or it looks fine with little in the middle.  But, in use it's a night and day difference.  The DMM went from feeling used and abused to aged and dignified, as any VFD display should feel these in this day and age.

If I could do it over again, I'd spend a little bit of time sanding the edges of the display. They look ugly and rough in the photos, but aren't noticeable in real life. 

I've attached the highlight photos but have a bunch of pictures in an Imgur album.

Thoughts?

[nctnico]

In a similar case I used regular scratch remover intened for cars. That seems to work equally well with much less work.

[xrunner]

I think it's a fine job, nice work saving the logos too. 

[TiN]

Good job 

[HighVoltage]

Looks really nice.
This must have taken a lot of time to get it so nice and not touching the name and model number writings.
 

[2bluesc]

Looks really nice.
This must have taken a lot of time to get it so nice and not touching the name and model number writings.

Thanks.  Most of the magic was having the foresight to mask the logos with some tape over them before I started.  On the final polish, I removed the tape so there were no edges visible.

[Zucca]

I would have try to polish with toothpaste and to get the shiny back mineral oil...

[coromonadalix]

just done a meter  for this problem,  i've taken a 1000 grit sand paper with water,  made a good run all around in circular motion the plastic 3 times,  taken a 2000 grit with water, circular motion  3 times,  after that aplied novus 2  3 times, and bam    like new finish

Tried the tooth paste for my car headbeams, applied 5 times with humid cloth, worked like a treat loll   the Aim brand  seemed like a fine grit ...