Virus surgery: Re-Potting 101 (warning - many photos!)

[riverman]

Step 1.
Does your cat look like this?

or like this?

No? Then rub it on its chin, between the ears, or on its belly until it starts smiling, then continue to step 2.

Step 2.
Place JB weld on either side of the pots like in the picture below.

less is more, but less than I have pictured is less in a bad way. more than I have is probably alright for a B/classic, as the threaded portion does not even make it to the faceplace. two out of four corners of each pot will have an empty hole, and the other two will have blue plastic knobs poking out. I am not sure how much JB weld you can pour into those holes before the pot is garbage, but unless you are good with a soldering iron, I recommend being careful. a few of my pots were had a bit seep into those holes, but I wasn't to concerned because I've been repairing electronics for a decade anyhow. Only one of the pots pictured was solid enough to not bother JB welding. I applied it to the pots like in the above picture (both sides, not just the pictured side) to about 75% of my pots, and they are solid as new.

How sturdy is this fix? Well, as long as you mixed the JBweld properly and gave it a good 24 hours to cure, it should outlast the pots themselves, based on my experience with this stuff (I've gone through probably five litres of this stuff over the years).

Step 3.
Why does this happen?


Well, two main reasons. One, is that the metal part you can see here should protrude through the faceplate, and a washer and a nut should adhere it to the faceplace for added rigidity. If your pot is really shaky, pop off the knob and move it back and fourth. if th black plastic post moves but there is ABSOLUTELY ZERO play in the threaded metal part you can see in the picture, then this JBweld job won't do crap, and the plastic components of the pot are worn out. If the threaded cylinder does have any sort of play, it is because it wasn't mounted to a sturdy surface in the first place which is definitely access' fault. This is probably a fault you will find in other modern synths as well, and you can check to see if this design defect affects any synth by simply pulling off the knob and looking in. Is the inside of the shaft threaded? it was almost positively designed to be mounted around the collar.

The second complaint is the plastic posts used in these pots. they definitely skimped out on the pots for these, and for an extra $5 worth of parts could have installed pots with a metal post. If you treat your knobs properly and the threaded collars were properly locked down, these pots would last a reasonable amount of time, so this minor complaint is greatly surpassed by the first one. If I ever break a pot completely, I'm going to order a few sturdier metal pots to experiment with, but I'm pretty sure my fix will outlast me.

Step Namnibor.
Please continue treating electronic devices with respect, like most people should but nobody does. It is usually pretty obvious (to completely biased me) how mechanical things are intended to be treated, so anything that twists but doesn't have any functionality by rocking should be turned, not rocked. It was after getting my virus back from lending it out that I had to fix half the pots in the first place, but to be fair, they wouldn't have done this if they were properly mounted in the first place. Again, you can see if this common design flaw exists in any knobbed thing by popping off the knob itself and seeing if the collar is threaded (most are), and if there is a nut holding that collar to something rigid as per its design.

Step Future Plans.
I'm not sure how you fellas feel about mods, but this summer's mod project is a pair of TOTALLY FUNKY ears for this sucker. left ear will have a pitch/mod wheel and a rather basic 16 step sequencer, and the right ear will have a one or two octave keyboard in the style of an accordion. if people on here are into that sort of thing, I'll start a thread when I'm starting on it.

Step Other Questions.
If I'm forgetting something or not specific enough about something, let me know.

[namnibor]

This may seem a bit ~*mad*~ but perhaps an even easier and pragmatic way to *keep* the pot stems upright ALL the time, no matter what:

Without even having to open-up the Virus, providing one's pots are all okay or have been fixed per this great post--could one just remove only the knobs and place simple black anodized flat washers that are small enough to where one would not see it once knob is replaced, making sure the center hole in washer *just fits* diameter of encoder/pot stem, and affix flat washer to flat Virus fascia, centered, thus not ALLOWING any side to side play in first place?

Plastic washers can even be found if friction of metal against plastic stem is a worry and super glue GEL would spread less and on that note, less of course is best, making sure it's adhered by four equal points. The tubes allow you to have needle-sized applicator.

Am considering doing this as a preventative measure since both the KB and KC are far out of warranty and in event some day it were necessary to open the hood and the tolerance would not allow this as freely, they would be simple enough to remove/replace. However, even if the washer's inner circumference is not *right on shaft*, having less tolerance for eventually moving can only help.

This would give stability but cannot stress how important it is to not use undue downward pressure on ANY encoder/pot as well to avoid calamity.

Lastly, never loan your Virus out to anyone in first place !

Feedback and criticism on this caffeinated A-ha Moment is most welcome!!