True Bypass/Expression Pedal

[AzzR]

I have just aquired a Boss FT-2 Dynamic Filter that I want to use for my main wah with an expression pedal but dont want to have to stomp the pedal before moving my foot over to the rocker.

I want to build an expression pedal for the FT that also has a true bypass box built into it so that I can stomp the expression pedal which pushes down on the DP/3PDT switch which then bypass the FT which will be continuously on.

Which is the best wah pot to use the get the quick change from treble to bass and which resistor will I need to put on it to make it the same as the one in the EV-5 (not positive what that is) and how do I wire up the minimum volume pot (not sure the value of that one either).

Also with the expression pedal shells from small bear is it difficult to fit the rack and pinion gear and the pot?

Cheers

-Dream

[ayayay!]

Hmm, that's a good idea.  There's probably a couple ways to go with that.  Thinking....

[ayayay!]

Thought I had it but was way off.  Still thinking....

[ayayay!]

Okay, you could simply build a TB Loop into your shell from Small Bear.   Or just buy a broken or cheap wah off Ebay.   I'd recommend getting that to work first, then add the LED last.

So you'd need 5 jacks.  4 for the standard TB loop like this:    http://www.indyguitarist.com/temp/tb-loop.gif    (Thx Brian) And a 5th for the Exp input.  The 5th jack never touches anything on your 3PDT.  It's just directly wired to the pot.

The expression jack would only be for the FT-2 (obviously) and I think all you would need is a 100k (or whatever) pot wired to the jack.  Should be simple.  I've tried 3 wah or volume pedals on my FT-2 and they had different pot values.  They all operated the same so the FT-2 is pretty tolerant of different pots. 

That's the quick & easy way to do it.

Bonus:  Try it with different pots, and you could wire it up to a TR-2 or Phase 90 for example (with your own added TRS expression jacks on the pedals) to change rates on the fly. 

Cool idea!   Thanks for posting it.  I'm gonna have to try this too. 

[Austin73]

the ev5 is a 10k log pot with  a 50k lin pot attached for min volume control if that helps a little. i can open mine up again and show you the wiring if you require just let me know

Aus

[AzzR]

Awesome man thanks for that. So if I get a 100K wah pot and attatch a 10k resistor will that give a 10k value in the wah pot? So far the only things in unsure of is exactly how the minimum volume pot is wired up and which components come with the small bear wah shell (obviously not the pot) in terms of rack gear and how hard it is to assemble.

Instead of a fixed resisotr on the pot could you have a pot to adjust the value of the pot so you can use it with other pedals or will this affect the travel of the pot. Thanks for your help

-Aaron

[ayayay!]

I don't think you'll need the minimum volume pot, or an extra resistor to set anything.   I know that's built into your EV-5, but in this case it would just be a distraction.     In other words, you don't need if for this project. 

You could always add the minimum volume pot later though.  For now let's skip it. 

Other than that, yeah get a 100k wah pot, and a Small Bear "shell kit."  I don't know exactly what's in the kit, so you'd have to ask Steve or whomever at Small Bear.  Looking at the pics on the site it looks like one of the kits comes with at least the rack (long "toothed" arm) and the flange (P shaped plastic piece that puts pressure on the rack) but you need to check on that.  The pinion (toothed wheel) is built onto the wah pot. 

Back to the pot, the standard Hot Potz II is more than adequate, and so is anything Steve sells @ Small Bear. 

[AzzR]

Cool so the shell shouldn't be too hard. Will attaching the resistor to the wah pot affect the travel at all?

[ayayay!]

I would leave the resistor out of it for now.  Yes, that will probably impact the travel of the pot in a negative way. 

Try it the way we talked about first, then we can take if from there.