CTS 500K pots the Long & Short Explained with Pics

[jonesy]

CTS makes both long and short shaft 500K pots, and many people seem to be unclear what to use in their Les Pauls so I thought this pictorial might help shed some light on the differences between the two and what guitars they are used in. The long pots have 3/4" long threads and the short pots have 3/8" long threads. That is just the threaded portion and does not include the shaft or drum.

Originally all Gibson LP's used the short shaft pots, as do the Historic series R8,R9 etc. but then in 1977 Gibson started using the long pots and mounted them inside the control cavity on a metal plate. Even if you remove the metal plate you will still need long shaft pots because of the thickness of the maple cap.

After 1977 all these guitars use the long shaft pots, Les Paul Custom, Standard, Studio, Traditional, Classic, Double Cut.

These guitars still use the short shaft pots: SG, 335, LP Special, LP Jr., the Paul, Flying V, Explorer, and Firebirds as well as all epiphone LP's.

In 2008 Gibson replaced the metal plate with the PCB board and mounted the long pots right into that.

The short shaft pots usually use one star washer, one flat washer and a control nut. Another nut can be put on first as a spacer if the short pots are being mounted into a pick guard or control plate.

The long shaft pots come with two nuts so you can adjust how far the threads stick through the carved top as it varies in thickness by V & T knobs holes. The nut goes on first, then the star washer, then the flat washer and nut goes on topside. Adjusting the bottom washer will allow how far the threads stick through the wood. You will need at least 3 threads to be able to get the washer and nut on.

There are always exceptions and probably a good idea to measure the thickness of the top or length of the old pots if you are not sure what your guitar needs.

 

[nicolasrivera]

In the classifieds there are some members asking for this, hope they contact you as me and other have been heading them your way!

 

[jonesy]

Yeah I'd be glad to try and help out if anyone has any questions.

 

[OBX351]

Thanks for the post!

 

[matt@msscguitar]

Good post. I think one of the most key things to take away from the original content is that there are exceptions. For example, the '68 RI Historic takes long shaft, whereas all other Historic LPs take short.

Further, this past weekend, I installed a harness for Maplehead872 in his 1975 Deluxe. To my surprise, it had Long Shaft pots, not short. Pretty strange. The stock harness was definitely stock.

Lastly, and I don't know the exact model and year, but some Epiphones do require long shaft pots. This was a complete surprise, but Malikon can shed some light on this because he was the first one of our customers to discover this.

As a safe rule of thumb, when your taking about LPs, long shaft is usually a safe bet since you can always use an extra hex nut to tailor how much of the pot shaft protrudes through the guitar.

Good post, Jonesy.

 

[jonesy]

Good post. I think one of the most key things to take away from the original content is that there are exceptions. For example, the '68 RI Historic takes long shaft, whereas all other Historic LPs take short.

<snip>
Good post, Jonesy.

Thanks Martin, yeah there are always exceptions to the rule for sure. I think some of the 60's Tribute LP's may even take the long shaft pots as well. Always best to double check what you need before hand just to be sure.

 

[matt@msscguitar]

Thanks Martin, yeah there are always exceptions to the rule for sure. I think some of the 60's Tribute LP's may even take the long shaft pots as well. Always best to double check what you need before hand just to be sure.

No doubt. I swear Gibson does this stuff on purpose to drive guys like us crazy Lol!

 

[Ayton]

The long shaft pots come with two nuts so you can adjust how far the threads stick through the carved top as it varies in thickness by V & T knobs holes. The nut goes on first, then the star washer, then the flat washer and nut goes on topside. Adjusting the bottom washer will allow how far the threads stick through the wood. You will need at least 3 threads to be able to get the washer and nut on.

In the order highlighted above, where do the plate and maple top go? Can we spell it out linearly, all the way from pot to knob, for people like me? As so:

Pot / nut / star washer / plate / maple / flat washer / nut / knob

I'm putting one of these cavities back together after a rewire. 90s Standard with the plate, CTS 500k longs all around. Some have three nuts which can't be right.

 

[jonesy]

I'm putting one of these cavities back together after a rewire. 90s Standard with the plate, CTS 500k longs all around. Some have three nuts which can't be right.

The thickness of the top varies from hole to hole because of the carved top so Gibson may have used an extra nut as a spacer where the top was thinner, I have seen that before with pots mounted to the metal plate.

 

[Ayton]

The thickness of the top varies from hole to hole because of the carved top so Gibson may have used an extra nut as a spacer where the top was thinner, I have seen that before with pots mounted to the metal plate.

Okay, cheers. Is the order I posted correct? It was kind of a guess.

 

[jonesy]

Okay, cheers. Is the order I posted correct? It was kind of a guess.

No, the pots set right on the metal plate or sometimes there is a flat washer in between, then there is a nut on the bottom of the plate to hold the pot tight. Then there are the spacers nuts, washers and top control nut etc. It varies a little from year to year from what I have seen. I pulled this metal plate out of a 2008 Left handed Les Paul Standard, it did not have the PCB board in it, maybe because it was a Lefty?

 

[patrickBOOTH]

Good post. I think one of the most key things to take away from the original content is that there are exceptions. For example, the '68 RI Historic takes long shaft, whereas all other Historic LPs take short.

Apparently this isn't true. The majority of the 68 Custom RI owners on here found short shaft pots in their guitars.

 

[matt@msscguitar]

Apparently this isn't true. The majority of the 68 Custom RI owners on here found short shaft pots in their guitars.

Interesting since we've personally seen 2 that were in fact long shaft. No surprise though really, Gibson is all over the place with this stuff.

As I already mentioned Maplehead872's 1975 Deluxe should have had short shaft, yet the stock wiring was long. Go figure.

 

[Ayton]

Thanks for the pics, Jonesy – exactly what I failed to find on Google image search!

Of course, now I'm more confused as they each have three nuts and no lock washer. Maybe it's under the plate?

I do know that I need to redo mine again, as some stick up too much and some barely have a thread above the maple. I'd thought the neck controls would have the most wood to go through, but they've come out too high and the bridge controls too low.

This time maybe I will be a genius and check them before resoldering the bridge ground.

 

[siggy14]

I am bit confused, if you remove the metal plate why would you still need long shaft? Is the maple cap that much thicker on the later les pauls?

 

[jonesy]

I am bit confused, if you remove the metal plate why would you still need long shaft? Is the maple cap that much thicker on the later les pauls?

The holes by the neck volume and tone are to thick for the short shaft pots (carved top) so you need the long. The metal plate is just an easy way for the factory to mount the controls.

 

[siggy14]

OK thanks, so on the historics they keep maple top thinner I take it.

The holes by the neck volume and tone are to thick for the short shaft pots (carved top) so you need the long. The metal plate is just an easy way for the factory to mount the controls.

 

[leocuellar]

Hello, great information here. Does anyone know what kind of pots are in the 2012 Gibson LP Standards? long or short?

Thank you!

Leo.

 

[matt@msscguitar]

Hello, great information here. Does anyone know what kind of pots are in the 2012 Gibson LP Standards? long or short?

Thank you!

Leo.

Long

 

[jonesy]

OK thanks, so on the historics they keep maple top thinner I take it.

Yeah around 1976-77 or so the carved maple tops got a little thicker and Gibson went to the long shaft pots mounted on the metal plate for the LP Customs and Standards.