"shafted" with Weber potentiometers?

[cdw2000]

A question for those that have built Weber amp kits or have purchased Weber parts: Are the solid-type potentiometer shafts the standard 1/4" diam? In other words have you successfully used standard non-Weber knobs on them?

The reason I ask is that I bought several pots from Weber along with several other parts to use in my own-design tube amp. I just received some chickenhead knobs that I purchased off e-bay and when I tried to install them, to my surprise, they would not fit. The shaft diameter was too big.

Just to be sure I tried the knobs on some Alpha and CTS pots that I had on hand and they fit fine, so the knobs are OK.

So I'm wondering if others have had this problem or did Weber happen to get a mis-marked lot (metric vs. english)?

I sent an email to Weber but have not yet received a response.

[Don]

Metric pots usually have a 6,0mm [.236"] shaft compared to inch pots that have a 1/4" [6,35mm] shaft. So inch knobs usually end up being loose on metric pots. Maybe yours have 6,5mm [.256"] shafts?

I believe that I have Weber sourced pots on my 5E3 clone (I didn't build it). The shafts are 1/4" and Fender branded knobs fit perfectly, though the threaded bushing is metric (maybe 8,0mm [.315"] dia.) and the cheesy die-cast nuts are 10mm.

I like their taper better than the taper on CTS audio taper pots.

[JAM]

There was a problem with the chicken head knobs not fitting the pots on the Weber kit (both pots and knobs from Weber). Ted had some comments that the knob maker had a very close tolerance on the holes and they needed to be chased with a 1/4" drill. I've never tried any other knobs on the Weber pots though.

[edited to add]

Ok, I measured the shafts with a digital micrometer and the pot shafts measure .2495".

[cdw2000]

Thanks for taking that measurement. That prompted me to check the knobs again.

It turns out I ASSUMED the control shafts were not correct, but after your response I found that a 1/4" drill bit will not fit into the knobs. I drilled one knob out and it now fits.

The knobs are most likely metric as are the other pots I tried them on.

My apologies to Ted Weber and company. I guess I will need to drill the knobs out to fit.

Me =

[Don]

There was a problem with the chicken head knobs not fitting the pots on the Weber kit (both pots and knobs from Weber). Ted had some comments that the knob maker had a very close tolerance on the holes and they needed to be chased with a 1/4" drill. I've never tried any other knobs on the Weber pots though.

Now that you mention it, I have noticed that knobs from Weber are very tight on pots from Weber. This was the case with their chicken head knobs as well as the white knobs used in the Cattledrive kit.

[NTBluesGuitar]

I just put a set of Weber's knobs on Alpha pots.

At first they wouldn't fit, then I noticed that there was some metal sticking out from where the set screws were machined in. Once I scraped it away, the knobs fit...snugly, but they fit.

[cdw2000]

Just to clarify with my original problem - my knobs are not from Weber. Only the pots were.

The pot shafts appear to be exactly 1/4". The knobs are smaller, I think they are for 6mm shafts. Drilling one out with a 1/4" drill, I could partly get the knob on and it was very tight, so I used a 17/64" drill.

[NTBluesGuitar]

My bad...I was thinking the other way around.

[yankeerob]

I have found that the metal shafted Alpha pots are pretty damned good - I've also gotten some plastic shafted Alpha's from Rapid and they're not bad either - the problem I have is that 10mm star washers slip around and don't seat the pots correctly and 8mm's are too small so I have to drill 8mm's out 'cause I can't get 9mm ones - it's a game - innit!