Yahoo Groups archive
Thread
2005-01-15 by RMC
Hello All I need to get one of the MS-10 or MS-20 "large" knobs (small style will do at a pinch), as used on the VCO waveform select or filter cut-off etc. If I can't buy one I might have a go at trying to mould one. the outside shouldn't be too difficult to get right but the inside "spine" hole might be beyond my meagre skills. Has anyone got one for sale please? If so, could they contact me off-list. Thanks RMC, England
2005-01-16 by Marvin Kaye
Hi RMC, I saw your post about the missing knob on your Korg. I wish I was writing you with good news, like I have one for you, but alas, that is not the case. Instead I am writing to commiserate with you, as I have a pair of Yamaha DMP11 mixers, one of which is missing a slider knob, a part which is not available from the Yamaha legacy hardware support depot here in "the colonies". It occurred to me as well that I might have to wind up molding my own, if one can't be found from the Yamaha factory in Japan (still awaiting reply to that post.) If, in fact, you do find yourself molding a knob, if you would be kind enough to share your method and materials selection with me, I would be happy to do the same. I have been considering creating the mold from that rubber-like molding material (much like silicone sealant, only a bit harder on the Rockwell C-scale of durometer), and have the same issues as yourself... getting a mold of the outside is simple, but the internals (being a slot surrounded by a pair of square depressions rather than a circular opening) are a bit more challenging. Do you have any further thoughts on the matter? If so, I would enjoy hearing from you. Good luck with your search and/or other solution. Thanks for your time. <Marv> --- In oldsynths@yahoogroups.com, "RMC" <rmc@r...> wrote: > Hello All > > I need to get one of the MS-10 or MS-20 "large" knobs (small style will do > at a pinch), as used on the VCO waveform select or filter cut-off etc. > > If I can't buy one I might have a go at trying to mould one. the outside > shouldn't be too difficult to get right but the inside "spine" hole might be > beyond my meagre skills. > > Has anyone got one for sale please? If so, could they contact me off-list.
> > Thanks > > RMC, England
2005-01-16 by RMC
Marv You and I are in the same boat - we need something idiot-proof if we want to mould our own. I reckon the only way I can do the insides of my Korg knob is to use a process similar to that used in car tyre "re-treads"; you take a part-worn tyre and coat the outside in fresh rubber into which you cut the tracks. My "plan" is to find a knob whose mating mechanism is suitably similar or identical to the spline approach that my Kog uses. I'll take it to work and get it turned down on a lathe if necessary. Then I will make a mould of my existing knob, try to find a suitable plastic to cast a replica, and then suspend my donor knob in the middle of the mould and cast it into the middle of a new copy. If you can find something that fits your DMP11, even if it is wrong, I think a similar half-way house approach might work. As far as moulding is concerned, there are "alginate" based (seaweed) jellies that give very high resolution, and also the silicon-elastomer type that you refer to. The tricky but for me will to find a thermosetting plastic that is self coloured and looks just right. If I am going to make a copy it *has* to be perfect. Otherwise I might as well just stick some bakelite knob off a 1942 valve wireless on the front! if I do get anywhere with making a mould, I will let you know. Thanks for getting in touch - at least we both know we aren't alone in our feeble quest! Cheers Richard Craven England ----- Original Message -----
From: "Marvin Kaye" <marv@...> To: <oldsynths@yahoogroups.com> Sent: Sunday, January 16, 2005 6:27 PM Subject: [oldsynths] Re: WTB: replacement knob for Korg MS-10 or 20 etc. > > > Hi RMC, > > I saw your post about the missing knob on your Korg. I wish I was > writing you with good news, like I have one for you, but alas, that > is not the case. Instead I am writing to commiserate with you, as I > have a pair of Yamaha DMP11 mixers, one of which is missing a slider > knob, a part which is not available from the Yamaha legacy hardware > support depot here in "the colonies". It occurred to me as well that > I might have to wind up molding my own, if one can't be found from > the Yamaha factory in Japan (still awaiting reply to that post.) If, > in fact, you do find yourself molding a knob, if you would be kind > enough to share your method and materials selection with me, I would > be happy to do the same. I have been considering creating the mold > from that rubber-like molding material (much like silicone sealant, > only a bit harder on the Rockwell C-scale of durometer), and have the > same issues as yourself... getting a mold of the outside is simple, > but the internals (being a slot surrounded by a pair of square > depressions rather than a circular opening) are a bit more > challenging. Do you have any further thoughts on the matter? If so, I > would enjoy hearing from you. Good luck with your search and/or other > solution. Thanks for your time. > > <Marv> > > > --- In oldsynths@yahoogroups.com, "RMC" <rmc@r...> wrote: >> Hello All >> >> I need to get one of the MS-10 or MS-20 "large" knobs (small style > will do >> at a pinch), as used on the VCO waveform select or filter cut-off > etc. >> >> If I can't buy one I might have a go at trying to mould one. the > outside >> shouldn't be too difficult to get right but the inside "spine" hole > might be >> beyond my meagre skills. >> >> Has anyone got one for sale please? If so, could they contact me > off-list. >> >> Thanks >> >> RMC, England > > > > > > > > Yahoo! Groups Links > > > > > > >
2005-01-16 by Marvin Kaye
HI again, Richard, I've been kicking around the idea of molding up some other (non- musical) parts for awhile, and this little episode has finally pushed me over the edge. I went ahead and ordered some molding silicone, release agent, and black urethane casting resin. I imagine I'll have all the "fixins" by next weekend. Naturally I had to order enough to make 200 slider knobs, but if I have good luck with my parts I'll be glad to make you a copy of yours... although all that shipping back and forth across the pond could make this a very long process. I've been working with composites for a number of years, although this will be my first venture into do-it-yourself injection molding, so I'm looking forward to the new challenge. My slider knob has a 1mm thick white (pointer) line that runs horizontally around its circumference that adds a bit more challenge to the project... I'm thinking I'll make an initial cast part into which I can mill the 1mm slot around its middle (it's nice to have a machine shop at hand) and use that to create a new exterior mold, then use an actual knob to mold the rear, with the notch for the slider shaft. One advantage to this approach is that the parting line will be at the exact back of the knob, so any flash will be removed invisibly. Once the black part is released from the mold I can apply some white casting resin to the slot, sand away the excess and polish off the whole thing once it's all cured up. A ton of work to duplicate a 50 cent part, but at least it will be right. I just hope the casting resin's black matches the black of the original knob. We'll see. <marv> --- In oldsynths@yahoogroups.com, "RMC" <rmc@r...> wrote: > if I do get anywhere with making a mould, I will let you know. Thanks for > getting in touch - at least we both know we aren't alone in our feeble
> quest! > > Cheers > > Richard Craven > England
2005-06-21 by ascii_me
Can you send me a pic of the knob you are looking for? I may have it. Email to rorymcd@... Thanks Rory McDonald OldSynths Moderator --- In oldsynths@yahoogroups.com, "Marvin Kaye" <marv@l...> wrote:
> > HI again, Richard, > > I've been kicking around the idea of molding up some other (non- > musical) parts for awhile, and this little episode has finally pushed > me over the edge. I went ahead and ordered some molding silicone, > release agent, and black urethane casting resin. I imagine I'll have > all the "fixins" by next weekend. Naturally I had to order enough to > make 200 slider knobs, but if I have good luck with my parts I'll be > glad to make you a copy of yours... although all that shipping back > and forth across the pond could make this a very long process. I've > been working with composites for a number of years, although this > will be my first venture into do-it-yourself injection molding, so > I'm looking forward to the new challenge. My slider knob has a 1mm > thick white (pointer) line that runs horizontally around its > circumference that adds a bit more challenge to the project... I'm > thinking I'll make an initial cast part into which I can mill the 1mm > slot around its middle (it's nice to have a machine shop at hand) and > use that to create a new exterior mold, then use an actual knob to > mold the rear, with the notch for the slider shaft. One advantage to > this approach is that the parting line will be at the exact back of > the knob, so any flash will be removed invisibly. Once the black > part is released from the mold I can apply some white casting resin > to the slot, sand away the excess and polish off the whole thing once > it's all cured up. A ton of work to duplicate a 50 cent part, but at > least it will be right. I just hope the casting resin's black > matches the black of the original knob. We'll see. > > <marv> > > > --- In oldsynths@yahoogroups.com, "RMC" <rmc@r...> wrote: > > > if I do get anywhere with making a mould, I will let you know. > Thanks for > > getting in touch - at least we both know we aren't alone in our > feeble > > quest! > > > > Cheers > > > > Richard Craven > > England
2005-06-21 by RMC
Rory Thanks for offering to help, but in the end I found someone at work who has a hobby interest in making plastic items. He has made a handful of perfect replicas for me, indistinguishable from the originals! Cheers Richard Craven England ----- Original Message -----
From: "ascii_me" <rorymcd@...> To: <oldsynths@yahoogroups.com> Sent: Tuesday, June 21, 2005 3:30 PM Subject: [oldsynths] Re: WTB: replacement knob for Korg MS-10 or 20 etc. > Can you send me a pic of the knob you are looking for? > I may have it. > Email to rorymcd@... > Thanks > Rory McDonald > OldSynths Moderator > > > --- In oldsynths@yahoogroups.com, "Marvin Kaye" <marv@l...> wrote: >> >> HI again, Richard, >> >> I've been kicking around the idea of molding up some other (non- >> musical) parts for awhile, and this little episode has finally pushed >> me over the edge. I went ahead and ordered some molding silicone, >> release agent, and black urethane casting resin. I imagine I'll have >> all the "fixins" by next weekend. Naturally I had to order enough to >> make 200 slider knobs, but if I have good luck with my parts I'll be >> glad to make you a copy of yours... although all that shipping back >> and forth across the pond could make this a very long process. I've >> been working with composites for a number of years, although this >> will be my first venture into do-it-yourself injection molding, so >> I'm looking forward to the new challenge. My slider knob has a 1mm >> thick white (pointer) line that runs horizontally around its >> circumference that adds a bit more challenge to the project... I'm >> thinking I'll make an initial cast part into which I can mill the 1mm >> slot around its middle (it's nice to have a machine shop at hand) and >> use that to create a new exterior mold, then use an actual knob to >> mold the rear, with the notch for the slider shaft. One advantage to >> this approach is that the parting line will be at the exact back of >> the knob, so any flash will be removed invisibly. Once the black >> part is released from the mold I can apply some white casting resin >> to the slot, sand away the excess and polish off the whole thing once >> it's all cured up. A ton of work to duplicate a 50 cent part, but at >> least it will be right. I just hope the casting resin's black >> matches the black of the original knob. We'll see. >> >> <marv> >> >> >> --- In oldsynths@yahoogroups.com, "RMC" <rmc@r...> wrote: >> >> > if I do get anywhere with making a mould, I will let you know. >> Thanks for >> > getting in touch - at least we both know we aren't alone in our >> feeble >> > quest! >> > >> > Cheers >> > >> > Richard Craven >> > England > > > > > > > Yahoo! Groups Links > > > > > > > -- > This email has been verified as Virus free > Virus Protection and more available at http://www.plus.net