rockmanrock

On a German forum they said the early M-Audio Oxygen ones were developed or made by Taiwanese company Midiplus. https://www.midiplus.com.tw/en/

One of the reason I bought this old one was because quite often things get cheapened over time. They certainly have cut down on the metal and heft but some people seem to be saying that the MK3 feels better than the old ones. I can get 127 on mine too. I think I could manage with not hitting the really low values but not getting to 127 would be annoying. Maybe they didn't account for the weights removal in the new one! I think the main complaint about all these cheap MIDI controllers is the lack of velocity consistency. There's a video by Merriam pianos on Youtube where he shows it's harder to control than a fancier keyboard action. This one:

With mine, after I'd taken it apart the second time I used some tape to hold it together until I've completely finished (yet to happen!). I got the soapy water tip from a Youtube video. I can't find it now but I think it was someone who was connected to one of these Chinese keyboard manufacturers. If the silicone rubber isn't ripped and the dot is still in place and not worn I think soapy water should be enough. I did see some repair videos where the dot had been worn off, must have been some heavy hitters. I think the idea is to thoroughly clean any debris out that would fall onto and mess up the contact. Sounds like you had the same trouble refitting the scanning PCB. Good tip with the paper clip. I had to take the rails off as the red mist was descending by that point. As I was doing it I thought this is probably how it was assembled in the factory, the PCB would go on then the rails. As for the screws into plastic, yes they're a bit dodgy - the outer case ones seem the most fragile to me. Hope you have noticed there are two self-tapper sizes, the ones along the front by the keys are short ones. If the threaded holes got really chewed up or cracked I think some epoxy putty (Milliput here in the UK) would fix it well.

They do have some weights in there, in your photo the rectangular end of the white keys and the circular part of the black ones have them moulded in. I've just removed and checked a white key of mine with a magnet! I think just taking off the rubber contacts, washing them and giving the carbon contacts a wipe would probably sort out any trouble. It would involve taking off every key but that's not too bad. This one I have was so filthy I had to go for a full wash. It really is time consuming doing this stuff though.

When I had mine to bits I washed the rubber contacts in mild soapy water and cleaned the PCB gently with IPA. I washed all the keys too, quite a job. You probably know this but the rubber contacts have a high and low side so make sure they go back on the right way.

Hi Reezekeys I bought one of these recently and did a big cleaning job on it. I agree, it is an okay keyboard to play. Not amazing but usable. When I had it open I rotated the black rubber key bushings and added some dabs of silicone lube and that improved the clackiness. I'm pretty sure it's not a Fatar, it's made in Taiwan or China so I would bet it's a Medeli, Huaxin, Ringway or similar. I've looked at the Mk3 quite closely on a Youtube video and I think it's an evolution of this one. People say they've made it lighter to play and it's certainly lighter in weight as it's now 6/7kg vs 11kg. I think they removed those steel rails and made them part of the plastic case moulding. They've also removed the steel weights from the keys. Have a look at 1 min into this vid: That little PCB you have removed from the keyboard is the key scanning one. I had a hell of a job putting it back on mine, I ended up unscrewing the steel rails. Another big problem I had was the pitch bend pot was worn and was constantly sending pitch bend. I bought another pot (Alps 10k linear RK11 series) but realised it has to be a special pitch bend one that has the resistance over a more limited rotation than a normal pot. M-Audio couldn't help with spares so I ended up getting one from a certain inNovative synth company as they use them in their controllers. They very generously sent me one for free. M-Audio had glued the pitch bend wheel onto the pot so that had to be drilled out to remove it. Still in the process of fitting it all back together. With hindsight I think I should have bought the new one!