anyone experienced any problems with the rotary button on the mk.2 ?

i have the problem that the plastic button is sliding on the metal and i have to "turn" direct the metal without the button on it. i think it's a heat problem? any ideas about that?

It's a heat problem - we're looking into it.

Was your player in direct sunlight at the time?

Rob

Argh !

Today i had the same problem !
The player wasn't in direct sunlight, but it was pretty hot in the car as i closed the roof of my convertible, and as my car is black it heated up quite much.

Eeeek, this was not pleasant, maybe we get knobs made of metal ??

Nils


P.S. I said it before and i say it now: Metal rules ...

hmmm.. at the time yes.. but now i have the problem all the type and i've removed the knob... i hope that you'll get a solution for that soon.. 'cause the empeg does not look very nice without the knob

KoS

Wouldn't metal suck because you would burn yourself on it? I know here (Phoenix), even plastic can get hot enough to feel like its burning.

I noticed this some time ago and Rob is looking in to it.

In the meantime, try making a tiny batch of araldite or similar two part epoxy adhesive. put 2 tiny drops on the control stalk, with enough room for the inner splines of the button to slide between.

I did this and it works like a charm. I just don't know how it sits with waranty.



Murray 06000047
____________________

i don't want ANY metal there.. i will the knob back ! ;-)

hey rob.. why is the metal stalk round and not flat from one site, so that if you had a knob which has the same shape it would sit perfectly on the stalk and why would never got to this problem ?
any solutions (without araldit) yet ? 'cause at the moment i can ONLY use the 4 buttons :-((

...any solutions (without araldit) yet ?

I betcha if you were to just wrap a piece of thin tape around the shaft, the knob would fit tightly enough not to slip. If regular tape is too thick, try that non-sticky teflon tape that plumbers use on pipe threads.

tanstaafl.

"There Ain't No Such Thing As A Free Lunch"

The button isn't flat on one side simply because the ones we use aren't available with flats on the shaft.

We're looking at other options for future batches. We have no problem with you doing mods to the shaft in order to make it grip better (eg, the teeny blobs of epoxy for example). This won't void you warranty, as long as you can get the knob off for servicing :)

Hugo

The knob is already a very tight fit. We actually had to make it less tight than the original protoype, as it ripped the switch apart when you tried to remove it!

The problem is that the properties of the material change with heat. Therefore we are looking to change the material.

Rob

> why is the metal stalk round and not flat

That's exactly what we asked the manufacturer. What a stupid design decision for a rotary control!

Unfortunately we couldn't find an alternative in time for the Mk.2 production run, and dropping the rotary control was not an option. I'm sure our plastics guys will have a solution soon.

Rob

uuppps.. i have already done this with the tape around the shaft..hmm... we'll be very carefully when i have to remove it.. shouldn't be a big problem.

Hmm. I hadn't even really used the volume control seriously until reading this thread and playing with it a few minutes.

Now, its pretty much useless, after playing with it for a few minutes.

Its on my desk here at work at the moment, in an air-conditioned environment. The player has been running for about a half hour, and the steel rotary stalk is quite warm on its own. So it seems the heat generated by the system, communicated through the steel is sufficient to loosen the plastic.

Also, it might be a case of the plastic not being hard enough, not just a grip issue: it seems that once you get it to break friction once, it takes less force every time thereafter to break friction, as if the fins themselves wear down quickly. Looking at the steel shaft under bright light, it has a fine powder on it now, which I believe is probably the remains of the original contact-edge of the plastic fins.

As a waiting-for-new-button solution, how about getting a clamp or crimper that will leave splines or knurl marks on the steel shaft itself (preferably splines) for the plastic knob to grip better? Hmm. It might be hard not to torque the shaft applying that kind of force.

Instead of re-thinking the button plastic, or deforming the shaft, how about fabricating a cylindrical steel shim that slides over the shaft tightly and that has splines on its outer surface?

The shim can fit very tightly, and still allow the button to fit loose (and thereby still allow disassembly), since it would be the splining on its outer edge providng the grip against the plastic fins inside the button, and not steel-plastic friction...

Plan: when I get home, I am going to find some thin (THIN!) copper tubing (with an interior diameter of at least 0.5mm LESS than the empeg's volume shaft's diameter), cut about a half inch of it, slice it down the side, slide it over a wooden dowel, crimp the HELL out of it with Vise-Grips (to leave spline marks) and then slide it over the empeg's steel volume shaft and see how grippy the volume button is after that.

I am still worried about those fins wearing down even more, however, in the future.


- - - - - - - - - - - - - - - - - --
MK2 #141, green, 12GB

I wasn't aware that the problem was that bad. The only player we've had with a loose knob has been Hugo's, whilst used in his MX5 with the roof down on a sunny day.

I'll give the plastics people a call tomorrow and check on their progress.

We can't knurl or otherwise machine the shaft of the switch - that's something the switch manufacturers would have to do before assembling the rest of the mechanism. We have now sourced a new switch with a flat shaft, but obviously we'll still come up with a fix for the current players.

Rob

I'll refrain from trying to mash the shaft then.

Either the unit has become so hot (about 2 hours solid operation, on my desk) or I've sufficiently shredded the fins inside the knob, but there's barely enough friction to hold it on.

If there is an interim fix that seems/works the best, could people submit them and have it be a FAQ until a new knob is shipped?

I guess the problem is compounded when the user is forced to twist the shaft with their fingers, getting oils and sweat on it, further reducing any friction.

- - - - - - - - - - - - - - - - - --
MK2 #141, green, 12GB

Hmmm.... just a thought that might work.

Try gluing the knob onto the shaft with rubber cement. It might hold it tightly enough to keep from slipping, but will still allow removal of the knob for disassembly.

tanstaafl.

"There Ain't No Such Thing As A Free Lunch"

Not a bad suggestion, Doug.

I have another suggestion/question. I don't own a Mk2, so I don't know the way the knob is constructed. But the knobs you get at Radio Shack have a little laterally-mounted "set screw" to tighten down upon the shaft. What about drilling a hole in the knob laterally and inserting a self-threading screw of some kind?

The Ratshack knobs have an advantage in that the screw has a metal sleeve so you can give it extra torque. So maybe this would be too much for it. This is just a suggestion, I dunno if it would work since I don't know what kind of plastic the Mk2 knob is made of and whether its shape would allow this kind of modification.

___________
Tony Fabris

Oh no!!! I did as Hugo suggested (a couple of blobs of epoxy) to make the round knob turn the shaft (it wouldn't turn it even sitting on my desk inside, let alone in the car)

Unfortunately the push-to-select part of the knob didn't work after that, I may have put it back on too tight with the glue. I just tried to remove the knob from the shaft, or at least to loosen it up, and the display of the empeg has just gone dead :( :( :(

I highly recommend to anyone to leave this alone until empeg come up with a better solution than glue seeing how easy it is to blow the display trying to remove a glued knob (e.g. to change the display color). Trust me, a non-working knob is better than no display.

The unit still appears to work fine, plays music, remote seems to work, but no display at all. Gonna send an e-mail to Rob in a moment to find out how to get this fixed.

Hoping this is covered under warranty... given I was following an empeg suggested fix to a problem.

I just tried to remove the knob from the shaft...

Yeah, I was figuring something like that might happen with the epoxy trick. That's why I thought the rubber cement might be better. The problem with rubber cement wouldn't be that the knob stuck too tightly, but that the rubber cement might not hold tightly enough to do any good.

Tony's idea with the set screw might be the way to go, it wouldn't have to be tightened down very much at all -- just a little more grip is all the knob needs -- but the way the knob is recessed within the faceplate leaves little room to get an allen wrench into the knob to tighten the setscrew, and the shaft might not extend far enough into the knob for the setscrew to reach it. Might not be mechanically possible to do that.

Sorry about your display hope it doesn't prove too difficult to fix.

tanstaafl.

"There Ain't No Such Thing As A Free Lunch"

I didn't actually mean glue the knob to the shaft, the epoxy comment meant putting a couple of little (ie, small enough to fit through the splines on the plastic) blobs of epoxy on the shaft, leaving it to *set*, then sliding the control onto it - ie, *not* gluing the knob on.

If the display has gone dead I suspect you've managed to pull the switch off the PCB enough that it's snapped the filler neck on the VFD. Ouch.

Hugo

Ok, so I'm an idiot :-(

I'm lucky, empeg have offered to replace my display and rotary knob as a gesture of good faith. However it's going to cost me $100+ in shipping charges and the use of my empeg for a week or two. Don't do what I did - wait for empeg to come out with an 'authorized' solution. They're not going to fix too many (any?) more under warranty.

That'll teach me to read more carefully. Well, you live and learn, otherwise you don't live.

Don't feel too much like an idiot, or to put it the other way round, most of us are idiots in that case :-)

I cannot count the times that i experimented with some expensive stuff of Hardware ( CAR or PC or DigiCAM or Scanner or empeg ) and i was just soooooo damn lucky to *not* utterly destroy everything that i belief that not humans have guardian angels, but gadgets have :-)
The guardian angel of your empeg must have been lazy at that time, so maybe also ask Hugo to replace that lazy son of a %&$§' guardian angel too !

:-)

Nils

Well - I have the same problem with the rotary button. It doesn't depend on if the car is in direct sunlight or not. It also appears by night. I already had a thought of putting a small rubber-tape between the knob and the metal. I think this would work.

TeeMcBee
Got my Mk2! # 080000143

I also ran into the problem, mine is now totaly useless, it started being a problem after i changed out my faceplate color once. I'm going to head out to the local radio shack to see if i can find a set-screw style knob. i also may talk to my machinests at work to see if they could whip up an aluminum replacement knob. :)

hey.. can i get the cad drawing for the plastic one to upload to our CMC? :)


12gig green mk2 -- 080000125

when hacking hardware, mistakes happen.. i've been a hardware tech for many years, and have done my share of damage to my personal, and customer equipment. i was simply trying to replace the CMOS batter on my 486 laptop a while back, and ended up fixing the batter, but frying the LCD panel (broke the ribon connector)..

[censored] happens

12gig green mk2 -- 080000125

Greetings!

I think everyone has. My favorites: when teaching an intro to microprocessors lab, watching students melt their circuit boards, or blow the plastic covers off of logic chips. "Ah, the smell of burning circuitry in the morning..."

My personal worst to date - installing a math coprocessor rotated by 90 degrees, and watching it turn bright orange saying "I didn't think there was an LED on it..."

Come on - someone out there has to remember the days of 387 coprocessors...



Paul G.
R# 15189

Well.. it's ugly as sin, but it atleast works, and doesn't cost much.

Radio Shack Part Number 274-415A
3/4" Hexagonal Control Knobs
1/4" shaft

slip it on.. tighten it down gently, and it works fine.. just make sure you keep it off enough so you can press the button..

empeg guys: why make the knob all plastic.. why not use a setscrew metal sleve and mold your knobs to it... maybe the guys that sell the knobs make a setscrew thing.

12gig green mk2 -- 080000125

The Empeg unit itself is generating enough heat to cause the volume knob to slip. I don't have a convertible. And the problem has presented itself on a warm day (85 deg F) while I was working on the unit in my garage. I usually drive to work at 9am and don't go home until 11pm and my drive is only 15 minutes, so heat hasn't really been a problem for a couple of weeks.

This is a design issue and I imagine that all units will need to be sent in for warranty upgrades soon, unless there is an easy knob replacement that can be mailed out. What about mounting a fan to the Empeg to get some of the heat out of it?

-Hoagy.

As a mechechanical designer I can safely say that a set screw, even tapped in plastic, will hold fine for this application. The question is can it be assembled with a set screw (ie can you get to the screw head to tighten it while the knob is in place)? A trick I've used is to score the shaft if a friction fit knob is loosening. I don't know how accessable this shaft is but a hardened prick punch (no, that's not what you do to someone hitting on your wife in a crowded bar in New Orleans) should do it. Even some 60 grit sandpaper or a steel dental pick can work. Try to get the scores running with the axis of the shaft. Be sure you support the shaft when scoring, it was not meant to take you pressing it sideways with all your might.

If you are REALLY careful you can also use an anaerobic thread lock (Loctite to you & me). The gotcha with this is if it gets into the workings of the switch you are HOSED. The Red is permanent, but Blue is probably sufficient. Try putting the smallest little bit (I'd use a medical syringe or a tiny drop on the end of a pin) in the hole near the bottom and get it on the walls a little. I was looking at the breakaway specs for this stuff earlier today, but I'm not a big enough weenie to actually have remembered the numbers.

I haven't had this happen to me yet, but I'm not to worried (I can order a new one from an stereolith house and get in under the radar for about $120 - after I model it of course).

Good luck. Radio shack knob on a new empeg...the HORROR...

;-)

-Zeke

just say you weren't paying much attention...