# Son of Ben / 2M Pot



## almondcity (Jul 1, 2021)

I cannot find any 2M PCB mount pots right now.  I've bought a B1M pot for now with the thought of just installing it and missing the last half of that knob.

Is there a way of potentially inserting a 500K resistor in series with the pot in order to "shift" the range of my B1M pot towards where it should be?  Like I would be OK if I can't turn my bass all the way to 0 or 10, but I would be OK with it going from 2.5 to 7.5.  Forgive me if I'm talking nonsense


----------



## Bricksnbeatles (Jul 1, 2021)

You can buy a comparable solder lug potentiometer, and transfer the resistive wafer to the housing of the PCB mount pot. It’s a bit of effort and it might take a few tries if you’ve never done it before, but after a while it becomes like second nature


----------



## Robert (Jul 1, 2021)

You can use a B1M dual potentiometer with a simple modification to the lugs.   

By putting the two gangs in series you'll effectively have a B2M pot.









						1M OHM Linear Dual Taper Potentiometer PCB Mount Round Shaft Dia: 6.35mm
					

ALPHA - Get It Fast - Same Day Shipping




					www.taydaelectronics.com


----------



## almondcity (Jul 1, 2021)

Do you mean to just get both lugs in each hole on the PCB? Or solder one pair to the other and insert just one set?


----------



## Feral Feline (Jul 3, 2021)

signal > lug 3 top gang, Output the top gang (lug 2) > lug 3 of the bottom gang, lug 2 > out. I think


----------



## Stew (Dec 29, 2021)

Bringing this one back from the dead. Have had my version 2 board for a while but only now getting time to put it together over Christmas.

Soooo ... follow Feral Feline's suggestion, does that mean lug 1 of a dual B1M doesn't get connected?


----------



## almondcity (Dec 29, 2021)

FYI I ended up using a 2M solder lug pot and just running wires to the pads to avoid thinking about it


----------



## spi (Dec 29, 2021)

Somebody posted this a while ago


----------



## Mike McLane (Jan 4, 2022)

For the SoB I just got a standard solder lug or vertical mount pcb pot and soldered hookup wire to it to extend to the mounts in the PCB.  Solid core works great, but if braided just solder the entire extent of the wire.  You've got three other pots that will secure the PCB in the enclosure.


----------



## spi (Jan 4, 2022)

I just built my SoB last weekend using a PCB mount Dual 1MB, modified as the picture above. 

I left the outer leads 1 and 2 alone.   They go right into the PCB.
I clipped off the inner lead 1. It is not needed.
I bent the inner lead 2 and outer lead 3 toward each other, until they were flat and touching, then I soldered them together.   Now they are joined and out of the way of the PCB.
I extended the inner lead 3 with a clipped diode leg to reach the PCB hole.
Then I soldered leads 1 and 2, and the extension of 3 to the PCB.

I should've taken a picture of it, hopefully this explanation made sense without the picture.


----------



## Preverb (Jan 5, 2022)

spi said:


> I just built my SoB last weekend using a PCB mount Dual 1MB, modified as the picture above.
> 
> I left the outer leads 1 and 2 alone.   They go right into the PCB.
> I clipped off the inner lead 1. It is not needed.
> ...


So basically like your diagram in post #8??


----------



## jwyles90 (Feb 11, 2022)

Mike McLane said:


> For the SoB I just got a standard solder lug or vertical mount pcb pot and soldered hookup wire to it to extend to the mounts in the PCB.  Solid core works great, but if braided just solder the entire extent of the wire.  You've got three other pots that will secure the PCB in the enclosure.


Sorry to hop into this so late, but I'm collecting parts for doing this build and can only find the standard solder lug pots as well. Was it pretty easy to solder wire from the pot into the PCB mount holes? It looks like those openings are larger than the other through holes so I'm curious if you did anything differently when soldering the connections.


----------



## Feral Feline (Feb 25, 2022)

Stew said:


> Bringing this one back from the dead. Have had my version 2 board for a while but only now getting time to put it together over Christmas.
> 
> Soooo ... follow Feral Feline's suggestion, does that mean lug 1 of a dual B1M doesn't get connected?




For some reason I missed this thread’s replies for a while…

I think it would be good to short the top gang’s lug 1 to top gang lug 2.

The lower gang’s lug 1 would go to the PCB’s pad-1 (be that in turn connected to ground or a resister etc depending on the circuit used.


----------



## space2001odyssey (Mar 12, 2022)

Bringing this thread up again since I have a short question:
I have a B2M at hand and the introduction says to bridge the two small extra solder pads between lugs 2 and 3 with solder. Since my lead-free solder is a bit difficult, I just bridged lugs 2 and 3 of the top row with a clipped diode wire - assuming this would have the same effect: is this correct?


----------



## jwyles90 (Mar 29, 2022)

space2001odyssey said:


> Bringing this thread up again since I have a short question:
> I have a B2M at hand and the introduction says to bridge the two small extra solder pads between lugs 2 and 3 with solder. Since my lead-free solder is a bit difficult, I just bridged lugs 2 and 3 of the top row with a clipped diode wire - assuming this would have the same effect: is this correct?


That should work! If you had any 60/40 solder on hand it's also pretty easy to create a bridge between the two pads with just that.


----------



## Raspymcnasty (Apr 10, 2022)

@Chuck D. Bones  helped me out a while back

Here’s the response he gave:

“


Chuck D. Bones said:


> There is another way.  Rescale some of the components so that B1M is the right value for the BASS pot.
> 
> C2 = 47nF
> R6 = 220K
> ...


----------



## gheorge77 (Apr 10, 2022)

Raspymcnasty said:


> @Chuck D. Bones  helped me out a while back
> 
> Here’s the response he gave:
> 
> “


Fyi. Small bear has the 2m in stock. I ordered a few on Friday.


----------

