'The Mod'

Remember I said to try and not get lubricant on the center contact? This is why... we're going to solder it back into place.

Add a little flux to make the solder flow easily between the contact and the rivet beneath.
The potentiometer housing is typically heat resistant, but don't linger there too long. Just make sure that a little solder gets down to the rivet and call it good.
Give the shaft a twirl to make sure that it rotates without binding.

Perfecto!
Time to modify the driver.
Touch the wires with a hot soldering iron and brush them away.
We're going to trick the servo driver into thinking that the potentiometer is always at a center-position with a pair of resistors.
Not just any resistors... we will need some high-precision resistors to make sure that we won't have to tweak software to account for drift.

It's hard to see, but these are .1% resistors. They are a little expensive, but well worth it for what work they will save you in the end.
You should be able to use any two off the tape... but I like to go the extra mile and find a matching pair.

Sure enough, they are what they say on the package!
It will take a steady hand to get the 0805 components in place... it doesn't need to be pretty - just functional.

Your trusty flux pen should help solder flow more easily if the tiny connections start to give you attitude.
This guide was first published on Nov 04, 2013. It was last updated on Nov 04, 2013. This page ('The Mod') was last updated on May 19, 2019.