JTV59 knobs (Model Selector and Alt Tuning) need to be pulled up to work

[SixtiesPopMan]

Testing my newly acquired JTV59, the Model Selector knob would not light up when pressed down. The guitar was powered by the XPS-AB power supply with two green LED indicating power was being supplied.

 

After some web searching, I gently pulled the knob up, and then pressed down - it worked! Same with alternate tuning knob

 

It seems that I have to do this every time when powering on the JTV59.  Not an immediate concern but at some point, with wear and tear, the knob's grip on the pot shaft might loosen. 

 

Are there any solutions or recommendations to address this?

[silverhead]

Sometimes those knobs can get a bit stuck because the edge can make contact with the guitar body. A common solution is to gently pry the knobs off the shaft (use a couple of spoons with a cloth beneath them to prevent damage to the body), stick a small wad of paper into the bottom of the knob, and replace it onto the shaft. This has the overall affect of raising the knob above the guitar body just enough to prevent the sticking.

[SixtiesPopMan]

@silverhead Many thanks for that solution!

 

From web reading, I'm guessing that my 2011 model has the short pot shafts.

 

Before I read your post, I cut thick grocery bag paper into a thin strip and then rolled it up it maybe a 3/8" thick plug. After inserting it into plastic knob shaft, the knob now has enough space to toggle on/off.

 

If the paper start to wear down and the problem returns, then at the point, I'll implement your solution. In the meantime, your solution has been added to my text doc survival guide.

 

So far, I'm off to a great start with the new/used Variax. Years ago, I had the cherry finish version.

 

Cheers!!!

[SixtiesPopMan]

On 8/6/2025 at 10:17 AM, SixtiesPopMan said:

maybe a 3/8" thick plug

Meant to say more like a 3/16" plug.

[SixtiesPopMan]

In today's episode of popular woodworking, we're going go over how to use a 3/8 inch diameter oak dowel from a big box store to create more durable spacers for the Variax Model Selector and Alt Tuning knobs.

 

Suggested tools

- a vice

- a very sharp chisel

- a small hand saw (I used a Japanese pull saw)

- fine grit sandpaper

 

About a two inch length of the dowel was cut and placed in a vice at about the midpoint of the diameter. ( I could have taken the time to measure the model selector stem and then mark both ends of the dowel with that dimension, to better approximate the actual contour of  the stem. I didn't do that as this procedure was intended as an exploration but in fact, ended up being the final setup.)

 

Using a very sharp chisel, the exposed surface of the dowel was shaved off flat.

 

The dowel in the knob shaft.

 

My initial paper spacer was about 3/16th, so I thought maybe double that would be a better length.

 

The ends were sanded down before inserting them into the knobs. As you can see in image below, I must have sanded the model selector spacer more aggressively as it sits lower to the surface.  The raised alt tuning knob was noticed immediately but what mattered more was that it worked!!! Based on this, a suggestion is to aim for a 5/16th length dowel spacer that will be a bit shorter after lightly sanding the ends, before insertion.