cutting into a pot cover

[pucho812]

I have a pot that is dirty. I would spray it with cleaner but it's sealed up. I excercised for 10 minutes and although it makes it better I really got to get detox in there.

Any problem with  cutting into the top of the back cover to make a slit so I can get spray in there.  outside of being careful and yes replace the pot does anyone see a problem?

 

[tomelectro]

What kind of pot? I've had success peeling open or drilling small holes in various types of pots for cleaner, but you need to be careful not to drill into the track or wiper mechanism.  I figure, if the only alternative is to replace it anyway, then what's the harm in trying?

 

[pucho812]

What kind of pot? I've had success peeling open or drilling small holes in various types of pots for cleaner, but you need to be careful not to drill into the track or wiper mechanism.  I figure, if the only alternative is to replace it anyway, then what's the harm in trying?

I was trying to peel part the cover off with no luck. It's the 600 ohm t bridge attenuator on an 1176 reissue. It is sctrachy.

 

[bruno2000]

I have a very old device called a Goesinta that has a threaded bushing on one end that is screwed onto the bushing of the pot, and the other end of the bushing terminates to a little red plastic piece that fits the opening in the valve of a spray can.  The theory is that the cleaner is forced between the pot shaft and the pot bushing.  It works well, but uses a LOT of cleaner/lubricant to get the job done.
Bruno2000

 

[sodderboy]

Yeah, and it washes all the thick grease out of the bushing.
If it is a can, drill into the side with a PCB drill.  If it is a Sfer or Clarostat plastic box, replace it. 
And I would call Universal and let them know.  Heck, you can walk over there, right?  If they are like Empirical Labs, they will offer to replace it gratis.
Big props to Empirical who send pots for free, and do major repairs for free.
Mike

 

[pucho812]

walking there would take a week as they are up north, way up north like a 5 hour drive up north.

It's  a pot like this

http://www.studioelectronics.biz/sunshop/images/products/detail_1151_600_ohm_bridgeT.jpg

the unit is almost 2 years old....  lets see what damage I can do.

 

[Walrus]

Having just this week drilled a hole in one of our 1176 pots, I can tell you the metal they use for the cover is bloody hard!!!!!!!!
Took a good 2 minutes of constant drilling with a good cordless and new sharp drill bit.

I gave up drilling on the second unit and managed to get the covers off to spray. Didn't think of trying to hacksaw a small cut into it. :
There is plenty of clearance to do this, and thats what I'll do on the others we have when required.

 

[pucho812]

I got through the input 600 ohm attenuator without issue and without ******* it up. I ****** up the 250K going to far and hitting the carbon.  Replaced the 250K and sprayed the 600 600 ohm attenuator. working great now. However this unit has other issues now, most likely because someone named Pucho accidentally fed 48V phantom into the output jack. an honest mistake by  being careless and worried about other things at that moment and being distracted. So now the unit shows it's compressing via gr meter but I don't hear compression/ and the unit has high hiss when no audio present.  back at it with a fresh mind later on....


fwiw if you plan to do this make sure the pot is full clockwise i.e. volume down all the way as there is less chance to hit the carbon that way.

 

[tv]

most likely because someone named Pucho accidentally fed 48V phantom into the output jack.

Hahaha... this has been done on several occasions to my bass. I ended up designing a low out. impedance preamp so that if somebody eventually fed me a phantom, all it could do is hurt itself..

 

[pucho812]

most likely because someone named Pucho accidentally fed 48V phantom into the output jack.

Hahaha... this has been done on several occasions to my bass. I ended up designing a low out. impedance preamp so that if somebody eventually fed me a phantom, all it could do is hurt itself..

if I **** it up, I own up to it... And sure enough I find a bad transistor.... If the trasistor pcb numbers on the UA units match the urei 1176 ln version then it makes perfect sense as that would be the first transistor going backwards from the output....

 

[schmidlin]

I learned this from fixing sealed wah pots.  DON'T drill into it.  Grab a dremel and a 1/2" silicon grinder bit.  Buzz into a corner of the metal can and go just a bit into the interior area.  This will NOT throw metal shavings into the pot, as the inside metal will *heal* itself creating a thin barrier.  Then take an Exacto blade and cut 3 sides of the healed barrier and peel it back.  Shoot in some silicon juice, peel it back and top it off with some superglue.  Magic!