replacing knobs?

Kindofblue · #1 08-23-2010, 12:49 AM

I recently got 3 chrome p bass knobs and want to replace the plastic volume knobs on my jazz bass. What is the best way to do this? I pulled on them a bit but it was hard to pull them so I stopped incase anything would break. Can anyone help me out?

C.Linton · #2 08-23-2010, 08:01 AM

Ther are two types of shafts on volume/tone controls. Either a "split-shaft" control with which you use push-on type knobs, and "solid shaft" controls which require knobs with set-screws. You need to make sure whether or not the knobs are just pushed on or if they have a set screw. Make sure you have the right kind of knob before switching them out. Not a good idea to mix the two.
Look on the sides of the knob, and if you see a hole there, you need to get a proper sized allen wrench and loosen the set screw in order to get the knob off. I don't know the right size off hand, I'm sure someone else here could help with that.

rojo412 · #3 08-23-2010, 08:25 AM

If we are talking about the Strat style knobs, which have the numbers and "volume" or "tone" written on them, then you have a tight fit. I've done a lot of these...

Use a very thin screwdriver or a butterknife and slide it under the knob, alongside of the shaft, not directly into the center.
Gently pry up on it, then rotate the knob a little and pry again. It will lift off enough to where you can grab it with your fingers and pull.

If you don't care about saving the knobs, just grab the middle part with pliers and pull.

But if there is a setscrew in there, then you need to loosen that and they will pop off easy.

TGLbass · #4 08-23-2010, 11:44 AM

Sorry--that guy has to be kidding--Right?

C.Linton · #5 08-23-2010, 12:57 PM

Who, me? Or the OP? What do you mean "kidding"?

TGLbass · #6 08-23-2010, 03:20 PM

Not you Mr Clinton. I just thought maybe the guy was messing with us. But forgive me if I am wrong, guy with the knobs.

C.Linton · #7 08-23-2010, 05:34 PM

I don't think he was. It seems a legit question to me, if you're a person who's not familiar with the two types of knobs.

202dy · #8 08-23-2010, 08:19 PM

Insert two small prying devices opposite on another and lift at the same time. Screw drivers can scratch a finish or pick guard if you're not careful. Popsicle sticks are safer for novice tool users.

Alternate prying on one side and then the other is a good way to break a knob, the potentiometer shaft, or both.

C.Linton · #9 08-23-2010, 08:42 PM

Quote:

Originally Posted by 202dy

Inset two small prying devices opposite on another and lift at the same time. Screw drivers can scratch a finish or pick guard if you're not careful. Popsicle sticks are safer for novice tool users.

Alternate prying on one side and then the other is a good way to break a knob, the potentionmeter shaft, or both.

And he still needs to determine FIRST if they are push-on or set-screw knobs before he starts ANY kind of prying or pulling.

202dy · #10 08-23-2010, 09:14 PM

Quote:

Originally Posted by C.Linton

And he still needs to determine FIRST if they are push-on or set-screw knobs before he starts ANY kind of prying or pulling.

Of course.

TGLbass · #11 08-24-2010, 06:01 AM

wrapping a screwdriver with a rag (enough wraps to get it under the knob without scratching anything) works too. Hold on to the knob with one hand and pry with the other.

He hasn't come back to respond.(op) I bet he already got those puppies off there. Personally I like Jazz knobs on a Jazz.

ejaggers · #12 08-24-2010, 07:44 AM

I'm with you TGLbass, I'd leave Jazz knobs on a Jazz. P knobs on a Jazz would probably look out of place.

C.Linton · #13 08-24-2010, 08:01 AM

Well, P-knobs on a Jazz to you and me might look out of place (that's why I replaced the P-type knobs on my Squier VM Jazz with proper Jazz type knobs), but if the OP wants P-type knobs on his Jazz , then that's what he wants.
Nothing wrong with that.

mulchor · #14 08-24-2010, 08:52 AM

I kinda like P-type on J, too.

And on the topic, I've never done it, but I could totally see myself strong-arming to pull off a knob that had a set screw. I remember putting a set-screw knob on and being frustrated that it was loose, 'til I finally stopped to look at it.

:O

C.Linton · #15 08-24-2010, 09:30 AM

Yah. Put a set-screw knob on a split shaft and it will compress the two halves of the shaft and will be way off center at the very least, and you may not be able to tighten it down enough at all to begin with. Use a push on knob with a solid shaft, it will either not fit at all or will be too loose. Yanking at a set-screw knob could possibly break it (or the pot itself even).

TGLbass · #16 08-24-2010, 02:41 PM

Jaco had P bass knobs on his jazz bass.

Kindofblue · #17 08-26-2010, 05:37 PM

Quote:

Originally Posted by TGLbass

Sorry--that guy has to be kidding--Right?

Is this not what talkbass is for? discussion and questions? I didn't know it was about discussing PEOPLES questions.

T-Bird · #18 08-27-2010, 12:36 AM

Hi.

I've said it before and I'll say it again:

If a plastic splined shaft knob won't budge with moderate force, break it. Unless it's a vintage one, in that case break the potentiometer instead.

Splined shaft potentiometers aren't IME designed for changing the knobs. Too much axial force, and the wiper plate will detach itself from the shaft.

IF OP has a set-screw knob on a solid shaft, the job may become easier.

Just my 0.02€
Sam

Scott1 · #19 08-27-2010, 01:52 AM

Quote:

Originally Posted by Kindofblue

I recently got 3 chrome p bass knobs and want to replace the plastic volume knobs on my jazz bass. What is the best way to do this? I pulled on them a bit but it was hard to pull them so I stopped incase anything would break. Can anyone help me out?

Get a rag. Pull the fabric taut and slip it under the knob, wrapping the fabric all the way around. Twist once to close the loop around the knob and firmly pull up. The knob will come up easier than you'll expect.

C.Linton · #20 08-27-2010, 08:53 AM

Quote:

Originally Posted by Scott1

Get a rag. Pull the fabric taut and slip it under the knob, wrapping the fabric all the way around. Twist once to close the loop around the knob and firmly pull up. The knob will come up easier than you'll expect.

Unless it's a set-screw knob. The OP has never bothered to inform us whether or not he has determined this. It would be a mistake to try and pull the knob like that if it's a set-screw. It's posssible he could damage it or the control. If it IS a push-on knob, the t-shirt trick should work.