How to Increase Potentiometer Pot Values

You can increase the resistance value of a potentiometer (pot) using the steps below. In the tutorial we take a 467K pot and change it to a 500K (exact) pot. NO electrical skills are necessary. Just patience.

Click on any photo below to see a larger version.
Here we have a CTS brand pot rated at 500K resistance. Increase Pot Value
The actual value of the pot is 467K. This is normal. I've never had a 500K pot out of the bag that was really 500K. Some are lower and some are higher. Thats just the way of the potentiometer. Increase Pot Value
You need to take the pot apart before we can change its resistance.

On the top of the pot there are four tabs that hold the top sleeve on the bottom of the pot.
Increase Pot Value
Use a small screwdriver or similar device to pry up the four tabs. Increase Pot Value

You can now lift the pot from its bottom and separate its three parts.
Increase Pot Value

Increase Pot Value
Use a razor blade held a slight angle to scrape around the outside edge of the circular carbon track. Be careful and move in small increments. It is very easy to move too far at once or with too much pressure and accidentallly zip the razor blade across the track. Don't do that as it may make the pot unusable. Increase Pot Value
After one full scrape around the carbon track the pot value is now 488K. A 20K increase. It's still not 500K though, so let's get more. Increase Pot Value
You could do another scrape around the outside edge with the razor blade held a little more at an angle than before. For this example though, scrape around the inside edge of the carbon track. Same rules as before. Position the blade at a slight angle and move in small increments. Increase Pot Value
After two scrapes, one outside and one inside, the pot reads 500K. Increase Pot Value
Put everything back together. Increase Pot Value
We now have a 500k pot. Pretty cool, hmm? Increase Pot Value