Loose, rattly knobs

JerkMoans

comrades!

I seek counsel. The knobs on my LPJ are so loose in the turn that the slightest accidental contact will cause them to shift, modifying my hard-won toanz. 

Matters have now evolved to the state that they vibrate/resonate to certain bad-ass riff frequencies: irksome when twanging unplugged.

My first thought was to pull ‘em off and tape the shafts before replacing, although while that might deal with the resonance i dont think it would stiffen up the lack of resistance to being turned. All academic though ‘cos all manner of hopeful tugging has failed to get a knob off (fnarr).

May i ask whether anyone has any bright ideas? 

Apols cant embed pics from phone while commuting. Will resolve later.

https://imgur.com/a/bttKO7C

Alegree

CTS pots have larger ends than import style. If you've got knobs for CTS pots and import pots that could cause a similar issue.

Funkfingers

Is it the plastic knobs that are shifting around the pot shafts or the pot shafts themselves?

On splined shaft pots, the traditional remedy is PTFE tape.

It is possible that the knobs have been pushed on too firmly, crushing the split portions of the shaft inwards and reducing their grip. It is possible to gently reverse the bending. It might help to wedge something into the shaft split to resist the crushing. (e.g. Card.)

JerkMoans said:

all manner of hopeful tugging has failed to get a knob off (fnarr).

Prise them off with a pronged tool and something to protect the surface of the guitar body. I often use the tool for tightening Switchcraft toggle switches. 

ESBlonde

In terms of spinning at the slightest touch, I have heard of people taking off the knob and inserting a felt washer under the knob before replacing. It provides some friction/resistance against the scratchplate or guitar surface to the rotation without risking any internal electrical damage. Pumping the pot full with white grease is another more invasive trick. You need to address the floppy knob issue too, @Funkfingers has given you the right stear there.

scrumhalf

Another vote for PTFE tape here.

WezV

I thought everyone just used glue.  I see it on so many guitars where I need to remove the knobs, always fun.

JerkMoans

Funkfingers said:

Is it the plastic knobs that are shifting around the pot shafts or the pot shafts themselves?

On splined shaft pots, the traditional remedy is PTFE tape.

It is possible that the knobs have been pushed on too firmly, crushing the split portions of the shaft inwards and reducing their grip. It is possible to gently reverse the bending. It might help to wedge something into the shaft split to resist the crushing. (e.g. Card.)

JerkMoans said:

all manner of hopeful tugging has failed to get a knob off (fnarr).

Prise them off with a pronged tool and something to protect the surface of the guitar body. I often use the tool for tightening Switchcraft toggle switches. 

It’s the pot shafts themselves that spin too easily : the knobs are firmly anchored, and spinning them still adjusts the *timbre* and the volume. So it’s not that the knobs are loose on the shafts.

i do wonder whether tightening the nut holding the potentiometer in place might help... 

JerkMoans

ESBlonde said:

In terms of spinning at the slightest touch, I have heard of people taking off the knob and inserting a felt washer under the knob before replacing. It provides some friction/resistance against the scratchplate or guitar surface to the rotation without risking any internal electrical damage. Pumping the pot full with white grease is another more invasive trick. You need to address the floppy knob issue too, @Funkfingers has given you the right stear there.

Now there’s an idea. 

JerkMoans

Exciting update!

I got the knobs off and the issue is identified as the pot shafts being a bit loose and rattly. Gonna apply Vaseline to the shafts and see whether that assists with the red-hot action.

JerkMoans

...aaaand we have a solution. With thanks to all and especially @ESBlonde I finally solved it by slicing a rubber washer in half round the equator, and shoving the resulting thin rubber rings onto each shaft before jamming the knobs back on. Resonant rattling terminated; non-futile resistance to turning achieved.

scrumhalf

It strikes me that "loose, rattly knobs" is about as close as you can get to a perfect description of the average FB'er.

I vote that it goes under the FB logo at the top of every page.

FelineGuitars

Ok - the problem is that that guitar has the BKP labelled 550k pots which have a really loose friction 
A felt washer may slow down the movement.

Or you could have them swapped out for regular CTS 500k ones which are way stiffer to turn.

The knobs are not the issue - simply the build of the pots

JerkMoans

FelineGuitars said:

Ok - the problem is that that guitar has the BKP labelled 550k pots which have a really loose friction 
A felt washer may slow down the movement.

Or you could have them swapped out for regular CTS 500k ones which are way stiffer to turn.

The knobs are not the issue - simply the build of the pots

Thanks Jon: bodged home fashioned rubber washers did the job unobtrusively

Funkfingers

JerkMoans said:
Gonna apply Vaseline to the shafts and see whether that assists with the red-hot action.

I cannot believe that Bridgehouse has failed to comment on this.