Rejuvenating a Wah Pedal

[Lee]

I'm looking to fix my wah pedal so I can use it to record with. At the moment it makes a clicky/scratchy noise whenever it reaches the down position and touches the button. Is it more likely that I need to use some contact cleaner or does something need to be replaced? What brand of contact cleaner do people use? Any leads are greatly appreciated thanks.

[Lee]

So-far my research has established that using contact cleaner in the pot is a quick fix but eventually I would need to replace the pot with possibly a 100K Hot Potz assuming that's the problem. The pedal is a Crybaby 535Q which belonged to Kristian and I'm trying to get it sounding good again.

[Sammas]

Pots are often lubricated by the manufacturer. The crackling is often caused by the lube residing at one when of the wipers travel, usually as a result of lack of use. Before you try spraying it, see if you can remove it from the pedal and twist the pot shaft from one end to the other repeatedly to redistribute the lube.

Spraying the pot with contact cleaner will blast out any dust that might be causing the crackle, but it will also blast out the lube... if you end up going this route, caig sells a deoxit product that will relube the pot as well.

[Chris H]

......... and sometimes the crackle has nothing to do with lube or pot, and everything to do with the condition of caps in the circuit.

[waitup]

Yep... Bad caps could be leaking some DC to the pot... It's not always the poor pots fault

[Sammas]

I would have assumed that the presence of DC would have caused it to be scratchy through out the wiper travel? Not just at one end?

[Kurt]

I'm sure it could be capacitors or any number of other components but it is most likely to be the pot itself.

If you blast it out with contact cleaner you could try re-greasing it with the stuff they sell at hobby shops to grease the pots in old school remote control cars/boats etc. Alternatively you could buy a new pot for under $50 delivered off ebay.

[wez]

the pot is usually the culprit, they wear out pretty regularly. just get a new one.

however i'll make one recommendation... when i had to replace the pot on my hendrix cry baby, the replacement pot was readily available but cost about $60, which seemed excessive. after some shopping round for alternatives, i discovered the 'Whipple' wah kit for around the same price - which included a new pot, inductor, a true-bypass switch, and some replacement resistors to tailor the tone. installation was a doddle, and after trying the various resistor options, i settled on a tone that worked for me... and the pedal works and sounds better than new.

i will admit that the hendrix wah has a very specific tone, and the whipple wah does take it a little bit away from that "Achtung Baby'-era Edge/U2 sound, to something a bit more versatile.

Having said that... the 535Q is a really versatile pedal, the way you can dial in the different tones... so i'm not sure if you would want the full kit - but i would recommend it as a very cost effective option for anyone who wants to revive an ailing wah pedal.

[Lee]

Thanks guys I really appreciate all the input. I will be finishing my JLM BA2 pre's next wednesday with a tech friend of mine so I will see what he says and make a move. Thanks guys.

[Hookemeister]

it makes a clicky/scratchy noise whenever it reaches the down position and touches the button.

Hi Lee

I don't think this a cap/DC problem as it would show up as you move the pedal up and down, not just when the pedal reaches the down position.

It may not even be the pot... unless there's a crack in the carbon track. So let's see if we can determine if the pot is at fault.

First thing to do is lift the pedal up, then toggle the bypass footswitch up and down just to determine there's nothing wrong with it... make sure you've got signal going thru it.

Then remove the base plate and with signal going thru the wah, tap the circuit board with the handle end of a screwdriver and see if you hear the "clicky/scratchy noise"

The next thing I'd do is remove the geared bar that drives the gear on the pot.

Note: Before you do this, put a mark across where the pot gear and the pedal gear meet so you know where to put it when you reassemble it.

Now with signal going thru it, rotate the pot with your fingers and see if you still get the "clicky/scratchy noise". If you don't then you need to look elsewhere.

Is the pot soldered directly to the circuit board or it it connected with wires?

If it is connected directly to the circuit board then it could be an intermittent solder connection on the circuit board that's being stressed when the pedal bottoms out.

Can you post some pics of the inside of the pedal... might make it easier to figure out what the problem is.

Try the above and report back with your results.

Hope this helps

[Lee]

Wow, thanks Greg you're a legend! I will definitely follow your guide when I sit down on Wednesday to do it and report back. Thanks for your detailed reply.

[Djembe]

I have been given a Cry Baby Wah with a similar problem.
Lee, did you have any luck?
Can I just buy a 100k pot from Jaycar? Would it be any good?
Otherwise I will get one from the US when I am there shortly.