EMG BTC extra knobs - fit CTS?

[1bassleft]

I'm replacing all the electronics in an OLP MM3 5-string. My parts bag has an EMG BTC with black concentric knobs and a couple (I only need one) matching knobs for additional pots.

Seeing as I'm doing this work, I want to put in a quality vol pot such as a CTS audiio 500k. My problem is that I'm not sure that the knobs fit. The EMG site is a bit confusing, if anything I'm under the impression they're for 8mm shafts, and they haven't replied to an email. Annoyingly, I've left the gear at my workplace.

Can anyone who's fitted the BTC let me know that the spare knobs fit, and if I should get the CTS with solid or split shaft. The knobs have a locking screw, although CTS shafts have no flattened edge so the fit has to be reasonably good to begin with. EMG's own pots are considerably more expensive than CTS.

Any reply appreciated so I can order to minimize delay, thanks.

[joelb79]

Solid shaft pots that are rounded (no flat side) will take a screw set knob just fine. As long as the knob fits over the shaft and the scew tightens (get it on there good of course) then it should be fine. FWIW, the knobs that came off CTS pots attach just fine to the top of the EMG BTC that I have, and those knobs fit CTS pots just fine as long as the screw is there of course. I assume you using the non-concentric knob for a CTS pot? The EMG solid shaft pots are identical in shaft size to CTS's from what I can see. hope that answers your question.

Originally Posted by 1bassleft

Can anyone who's fitted the BTC let me know that the spare knobs fit, and if I should get the CTS with solid or split shaft. The knobs have a locking screw, although CTS shafts have no flattened edge so the fit has to be reasonably good to begin with. EMG's own pots are considerably more expensive than CTS.

Any reply appreciated so I can order to minimize delay, thanks.

[1bassleft]

Thanks for the reply. I tried out the EMG single knob on the split-shaft currently on the OLP. Good, tight push fit and the knurl should help the screw to grip. That was my only worry about the purely cylindrical solid shaft CTS. I placed an order for the split-shaft CTS from work, before I saw your reply. Should do the trick.

[1bassleft]

Just to tidy up a loose thread (groan). EMG's additional vol knobs push down snugly onto the CTS split-shaft and the screw should properly secure it. Saves me buying a chrome concentric to match the OLP standard.

[Hopkins]

I had to drill the brass out to 1/4 for the EMG knob that came with my BTC to fit a solid shaft CTS pot.

The knobs are kind of ugly, but I used them anyway, because I wasn't sure if a regular concentric knob set would fit on the BTC control.

[1bassleft]

aah, that's interesting. The solid-shaft I nearly ordered was 1/4" but the split was listed as 6mm. I assumed that the seller was rounding down from 6.35mm (1/4") but, going by what you say, maybe I got a 6mm CTS for the European market. I don't know, but I got lucky. Drilling out would be a pain. The EMG knobs are a bit un-pretty, but seem to work with the black OLP.

A standard (6/8mm) chrome concentric for $2.59 from Shen Zhen looks like it could've saved you the trouble

[Hopkins]

Drilling them is easy, it took all of 15 seconds. I tightened them in a vice and drilled into the brass with a 1/4 drill bit. It cut through the soft brass almost as easily as if it were wood.

[1bassleft]

Having fitted the EMG-supplied knobs, I'm looking at that Shen Zhen chrome concentric on the 'bay. I said the EMG vol was a bit unpretty, but at least it felt OK. Their concentric knob is more plasticky to the touch, especially the lower ring. Looks alright from a distance, but feels cheap.

I'll shell out $2.59 (incl shipping) for some chrome and see which I prefer. (BTW, I take your point about drilling out - it's quite a thick, smooth bore; nothing tricky.