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#1
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Bourns Pot Shafts Not Long Enough!
https://www.mouser.com/datasheet/2/54/tv09-777818.pdf
The length "L" is from where the pot sits on the PCB board, to the end of the shaft, but it looks like this L maxes out at 30mm, and I need 35mm. I'm fairly sure the original is a Bourns pot, because the bottom of it says "B202", which shows the taper profile, and the resistance value. What to do? Maybe I could cut off the tip of the original shaft, and just epoxy it onto the new one? |
#2
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Bourns Pot Shafts Not Long Enough!
On 10/12/2018 7:49 PM, Paul wrote:
https://www.mouser.com/datasheet/2/54/tv09-777818.pdf The length "L" is from where the pot sits on the PCB board, to the end of the shaft, but it looks like this L maxes out at 30mm, and I need 35mm. I'm fairly sure the original is a Bourns pot, because the bottom of it says "B202", which shows the taper profile, and the resistance value. What to do?Â* Maybe I could cut off the tip of the original shaft, and just epoxy it onto the new one? And the longest one that Digikey has in stock, is only 20mm long: https://www.digikey.com/product-deta...202-ND/3781125 But if I'm gonna epoxy the tip of the old shaft, onto the new one, it won't matter too much how short the new one is. |
#3
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Bourns Pot Shafts Not Long Enough!
On 10/12/2018 9:37 PM, Paul wrote:
On 10/12/2018 7:49 PM, Paul wrote: https://www.mouser.com/datasheet/2/54/tv09-777818.pdf The length "L" is from where the pot sits on the PCB board, to the end of the shaft, but it looks like this L maxes out at 30mm, and I need 35mm. I'm fairly sure the original is a Bourns pot, because the bottom of it says "B202", which shows the taper profile, and the resistance value. What to do?Â* Maybe I could cut off the tip of the original shaft, and just epoxy it onto the new one? And the longest one that Digikey has in stock, is only 20mm long: https://www.digikey.com/product-deta...202-ND/3781125 But if I'm gonna epoxy the tip of the old shaft, onto the new one, it won't matter too much how short the new one is. The alternative, is to just get a panel mounted pot, instead of a board mounted one like the original. Then I could just screw it onto the back panel: https://dt7v1i9vyp3mf.cloudfront.net...4yNFN9_s1a.jpg The screw and the washer will partially cover up the -20dB, -5dB, and MAX indicators that are on the back panel sticker, but the pot will function the exact same way, and quite possibly will last longer, as the panel mount pots are bigger. Any feedback is appreciated. |
#4
Posted to rec.audio.pro
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Bourns Pot Shafts Not Long Enough!
Paul wrote:
https://www.mouser.com/datasheet/2/54/tv09-777818.pdf The length "L" is from where the pot sits on the PCB board, to the end of the shaft, but it looks like this L maxes out at 30mm, and I need 35mm. I'm fairly sure the original is a Bourns pot, because the bottom of it says "B202", which shows the taper profile, and the resistance value. ** "B:" ios the cobe letter for "linear and 202 = 2000 ohms. What to do? Maybe I could cut off the tip of the original shaft, and just epoxy it onto the new one? ** Why not just saw a slot in the top of the new pot and adjust it with a small screwdriver ?. ..... Phil |
#5
Posted to rec.audio.pro
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Bourns Pot Shafts Not Long Enough!
In article , Paul wrote:
What to do? Maybe I could cut off the tip of the original shaft, and just epoxy it onto the new one? Epoxy won't work. Silver solder will for carbon pots, but it's hard not to damage conductive plastic ones. (I mean hard jeweler's solder, not the 2% kind for Tek scopes). Back in 1975, you could get replacement pots onesie-twosie from the shops that catered to TV repair stores, and they came with outrageously long shafts that you were expected to cut down to size. Those days are long gone. Mod-Pot is likely the only solution for longer shafts in onesie-twosies but you can try doing a search for length on digi-key. Today just about every pot is a custom item, making replacement a pain. Which is why I recommend it only as a last resort when cramolin and rebuilding won't help. --scott -- "C'est un Nagra. C'est suisse, et tres, tres precis." |
#6
Posted to rec.audio.pro
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Bourns Pot Shafts Not Long Enough!
On 10/13/2018 9:57 AM, Scott Dorsey wrote:
Epoxy won't work. Silver solder will for carbon pots, but it's hard not to damage conductive plastic ones. (I mean hard jeweler's solder, not the 2% kind for Tek scopes). Another possibility is to get a coupling - a short piece of thick wall tubing with two set screws - and couple another piece of rod of the correct diameter to the existing pot shaft. You could cut the shaft off the old pot that you're replacing and use that as the extension. You may have to cut off a piece of shaft off the new pot to make room for the length of the coupling. Really, though, I was going to suggest what Phil did - cut a slot in the end of the new pot's shaft to make it screwdriver-adjustable. I take it this it a replacement for the input gain control on the Event speakers, so it's not something you'll be changing often. -- For a good time, call http://mikeriversaudio.wordpress.com |
#7
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Bourns Pot Shafts Not Long Enough!
In message , Mike Rivers
writes Another possibility is to get a coupling - a short piece of thick wall tubing with two set screws - and couple another piece of rod of the correct diameter to the existing pot shaft. You could cut the shaft off the old pot that you're replacing and use that as the extension. You may have to cut off a piece of shaft off the new pot to make room for the length of the coupling. I remember those sleeves, with 4 rather than two set screws. There appear to be pot shaft extenders of various types on both US and UK ebay. -- Bill --- This email has been checked for viruses by AVG. https://www.avg.com |
#8
Posted to rec.audio.pro
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Bourns Pot Shafts Not Long Enough!
On 10/13/2018 6:57 AM, Scott Dorsey wrote:
In article , Paul wrote: What to do? Maybe I could cut off the tip of the original shaft, and just epoxy it onto the new one? Epoxy won't work. Silver solder will for carbon pots, but it's hard not to damage conductive plastic ones. (I mean hard jeweler's solder, not the 2% kind for Tek scopes). Back in 1975, you could get replacement pots onesie-twosie from the shops that catered to TV repair stores, and they came with outrageously long shafts that you were expected to cut down to size. Those days are long gone. Mod-Pot is likely the only solution for longer shafts in onesie-twosies but you can try doing a search for length on digi-key. Today just about every pot is a custom item, making replacement a pain. Which is why I recommend it only as a last resort when cramolin and rebuilding won't help. --scott "Rebuilding" as in trying to fix the original pot? Ok, I've cracked it open. There are two fingers for the variable resistance wiper, and two for the center pin. I will try to gently bend these metal fingers up, so that they touch the traces again, and then clean with the Deoxit Gold that I just bought (the guy at the store said everyone swears by it!). I'll let you know how it goes....but that's a good suggestion, after considering the alternatives! |
#9
Posted to rec.audio.pro
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Bourns Pot Shafts Not Long Enough!
On 10/13/2018 7:21 AM, Mike Rivers wrote:
On 10/13/2018 9:57 AM, Scott Dorsey wrote: Epoxy won't work.Â* Silver solder will for carbon pots, but it's hard not to damage conductive plastic ones.Â* (I mean hard jeweler's solder, not the 2% kind for Tek scopes). Another possibility is to get a coupling - a short piece of thick wall tubing with two set screws - and couple another piece of rod of the correct diameter to the existing pot shaft. You could cut the shaft off the old pot that you're replacing and use that as the extension. You may have to cut off a piece of shaft off the new pot to make room for the length of the coupling. Really, though, I was going to suggest what Phil did - cut a slot in the end of the new pot's shaft to make it screwdriver-adjustable. I take it this it a replacement for the input gain control on the Event speakers, so it's not something you'll be changing often. That is correct, this is the sensitivity/gain pot on the Event TR5. Agreed, I could do that, although the pots that Digikey have in stock are the "D" type shafts, so that would make it harder to adjust with a screwdriver. Plus, re-sale value is lower, when repairs are visible, and the speakers no longer match. I'm trying to repair the original pot now....stay tuned! |
#10
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Bourns Pot Shafts Not Long Enough!
On 10/13/2018 1:07 PM, Paul wrote:
On 10/13/2018 6:57 AM, Scott Dorsey wrote: In article , PaulÂ* wrote: What to do?Â* Maybe I could cut off the tip of the original shaft, and just epoxy it onto the new one? Epoxy won't work.Â* Silver solder will for carbon pots, but it's hard not to damage conductive plastic ones.Â* (I mean hard jeweler's solder, not the 2% kind for Tek scopes). Back in 1975, you could get replacement pots onesie-twosie from the shops that catered to TV repair stores, and they came with outrageously long shafts that you were expected to cut down to size.Â* Those days are long gone. Mod-Pot is likely the only solution for longer shafts in onesie-twosies but you can try doing a search for length on digi-key. Today just about every pot is a custom item, making replacement a pain. Which is why I recommend it only as a last resort when cramolin and rebuilding won't help. --scott Â*Â*Â* "Rebuilding" as in trying to fix the original pot? Â*Â*Â* Ok, I've cracked it open.Â* There are two fingers for the variable resistance wiper, and two for the center pin.Â* I will try to gently bend these metal fingers up, so that they touch the traces again, and then clean with the Deoxit Gold that I just bought (the guy at the store said everyone swears by it!). Â*Â*Â* I'll let you know how it goes....but that's a good suggestion, after considering the alternatives! Â*Â*Â* Ok, it turns out the wiper fingers are not at fault: The center pin trace is not connected to the center trace! There is continuity to both outer pins 1 and 3, but the center pin 2 is an open, which is somewhere embedded within the plastic housing! Dammit! I'm SOL! |
#11
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Bourns Pot Shafts Not Long Enough!
On 10/13/2018 1:39 PM, Paul wrote:
On 10/13/2018 1:07 PM, Paul wrote: On 10/13/2018 6:57 AM, Scott Dorsey wrote: In article , PaulÂ* wrote: What to do?Â* Maybe I could cut off the tip of the original shaft, and just epoxy it onto the new one? Epoxy won't work.Â* Silver solder will for carbon pots, but it's hard not to damage conductive plastic ones.Â* (I mean hard jeweler's solder, not the 2% kind for Tek scopes). Back in 1975, you could get replacement pots onesie-twosie from the shops that catered to TV repair stores, and they came with outrageously long shafts that you were expected to cut down to size.Â* Those days are long gone. Mod-Pot is likely the only solution for longer shafts in onesie-twosies but you can try doing a search for length on digi-key. Today just about every pot is a custom item, making replacement a pain. Which is why I recommend it only as a last resort when cramolin and rebuilding won't help. --scott Â*Â*Â*Â* "Rebuilding" as in trying to fix the original pot? Â*Â*Â*Â* Ok, I've cracked it open.Â* There are two fingers for the variable resistance wiper, and two for the center pin.Â* I will try to gently bend these metal fingers up, so that they touch the traces again, and then clean with the Deoxit Gold that I just bought (the guy at the store said everyone swears by it!). Â*Â*Â*Â* I'll let you know how it goes....but that's a good suggestion, after considering the alternatives! Â*Â*Â*Â* Â*Â*Â*Â*Â*Â* Ok, it turns out the wiper fingers are not at fault:Â* The center pin trace is not connected to the center trace! Â*Â*Â*Â*Â*Â* There is continuity to both outer pins 1 and 3, but the center pin 2 is an open, which is somewhere embedded within the plastic housing! Â*Â*Â*Â*Â*Â* Dammit!Â* I'm SOL! Â*Â*Â*Â*Â*Â* Ok, since I'm pretty sure this original pot is a Bourns one, because the dimensions are very close, would it be possible to buy a new pot, and replace the too-short shaft with the older, longer shaft? The wiper/finger metal looks to be in good shape still. Has anyone ever successfully done this before? |
#12
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Bourns Pot Shafts Not Long Enough!
In article , Paul wrote:
"Rebuilding" as in trying to fix the original pot? Ok, I've cracked it open. There are two fingers for the variable resistance wiper, and two for the center pin. I will try to gently bend these metal fingers up, so that they touch the traces again, and then clean with the Deoxit Gold that I just bought (the guy at the store said everyone swears by it!). Before doing that, you should have tried just squirting some cleaner in there. There's seldom any need to actually take the pot apart. You don't want the Deoxit Gold, you want the less aggressive stuff that has a lubricant in it, like FaderLube, which is also a Caig product and should have been on the same shelf. But try the gold cleaner and see. --scott -- "C'est un Nagra. C'est suisse, et tres, tres precis." |
#13
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Bourns Pot Shafts Not Long Enough!
In article , Paul wrote:
Ok, it turns out the wiper fingers are not at fault: The center pin trace is not connected to the center trace! There is continuity to both outer pins 1 and 3, but the center pin 2 is an open, which is somewhere embedded within the plastic housing! Yes, because the moving contact point is gunked up. Flush the whole thing with cramolin and it will likely be fine. Spray it in, work it back and forth, spray some more, work it back and forth. Dammit! I'm SOL! No, you aren't. You should just follow the advice I gave in my first message and flush the thing out with cramolin. Or Callube or FaderLube, or, as I said, whatever the currently fashionable Quietrole replacement is. --scott -- "C'est un Nagra. C'est suisse, et tres, tres precis." |
#14
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Bourns Pot Shafts Not Long Enough!
On 10/13/2018 2:29 PM, Scott Dorsey wrote:
In article , Paul wrote: Ok, it turns out the wiper fingers are not at fault: The center pin trace is not connected to the center trace! There is continuity to both outer pins 1 and 3, but the center pin 2 is an open, which is somewhere embedded within the plastic housing! Yes, because the moving contact point is gunked up. Flush the whole thing with cramolin and it will likely be fine. Spray it in, work it back and forth, spray some more, work it back and forth. Dammit! I'm SOL! No, you aren't. You should just follow the advice I gave in my first message and flush the thing out with cramolin. Or Callube or FaderLube, or, as I said, whatever the currently fashionable Quietrole replacement is. --scott No, you are misunderstand the situation. With the wiper and shaft taken off, there are two traces on the pot: one trace for the variable resistance, and one trace for the center pin. The trace for the center pin is NOT connected to pin 2. There is an open there, and it's somewhere embedded inside the plastic moulding. There's nothing I can do with it, without destroying it. I have ordered a few of the 2K Bourns pots, with the intention of taking apart one of them, and seeing if I can replace the too-short new shaft, with the older, but longer shaft. It might work. If it doesn't, I'll just cut a slot in the shaft, and use a screwdriver to adjust it, as has been suggested. Stay tuned. |
#15
Posted to rec.audio.pro
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Bourns Pot Shafts Not Long Enough!
On 14/10/2018 3:21 AM, Mike Rivers wrote:
On 10/13/2018 9:57 AM, Scott Dorsey wrote: Epoxy won't work.Â* Silver solder will for carbon pots, but it's hard not to damage conductive plastic ones.Â* (I mean hard jeweler's solder, not the 2% kind for Tek scopes). Another possibility is to get a coupling - a short piece of thick wall tubing with two set screws - and couple another piece of rod of the correct diameter to the existing pot shaft. You could cut the shaft off the old pot that you're replacing and use that as the extension. You may have to cut off a piece of shaft off the new pot to make room for the length of the coupling. Really, though, I was going to suggest what Phil did - cut a slot in the end of the new pot's shaft to make it screwdriver-adjustable. I take it this it a replacement for the input gain control on the Event speakers, so it's not something you'll be changing often. Or would a countersunk or different knob somehow reach the shaft. may have to enlarge the panel-hole if pcb-mounted pot. geoff |
#16
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Bourns Pot Shafts Not Long Enough!
On 14/10/2018 9:07 AM, Paul wrote:
On 10/13/2018 6:57 AM, Scott Dorsey wrote: In article , PaulÂ* wrote: What to do?Â* Maybe I could cut off the tip of the original shaft, and just epoxy it onto the new one? Epoxy won't work.Â* Silver solder will for carbon pots, but it's hard not to damage conductive plastic ones.Â* (I mean hard jeweler's solder, not the 2% kind for Tek scopes). Back in 1975, you could get replacement pots onesie-twosie from the shops that catered to TV repair stores, and they came with outrageously long shafts that you were expected to cut down to size.Â* Those days are long gone. Mod-Pot is likely the only solution for longer shafts in onesie-twosies but you can try doing a search for length on digi-key. Today just about every pot is a custom item, making replacement a pain. Which is why I recommend it only as a last resort when cramolin and rebuilding won't help. --scott Â*Â*Â* "Rebuilding" as in trying to fix the original pot? Â*Â*Â* Ok, I've cracked it open.Â* There are two fingers for the variable resistance wiper, and two for the center pin.Â* I will try to gently bend these metal fingers up, so that they touch the traces again, and then clean with the Deoxit Gold that I just bought (the guy at the store said everyone swears by it!). Â*Â*Â* I'll let you know how it goes....but that's a good suggestion, after considering the alternatives! Â*Â*Â* DeOxit Gold is great for what it's for, but treating/lubing pots isn't it. You need Caig FaderLube, or whatever it's current name is. It is a totally different thing to DeOxit Gold. geoff |
#17
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Bourns Pot Shafts Not Long Enough!
In article , Paul wrote:
No, you are misunderstand the situation. With the wiper and shaft taken off, there are two traces on the pot: one trace for the variable resistance, and one trace for the center pin. The trace for the center pin is NOT connected to pin 2. Right. There is a contact connected to the center pin which touches that trace. But the contact is bad, or that trace is dirty. Sometimes instead of having that second trace, there is a contact that connects to the side of the rotating shaft in order to provide the connection to the sliding element. Remember: the sliding element moves, the pin is static. Therefore there is a moving contact between the two. Moving contacts go bad. There is an open there, and it's somewhere embedded inside the plastic moulding. There's nothing I can do with it, without destroying it. There's an open there. Flood it with cramolin. Get cramolin behind the plastic molding. Everything that moves, get cramolin on it. Just pump it full until it comes squirting out. You can usually do this without taking the pot apart. What you are describing is one of the more common pot failure modes. --scott -- "C'est un Nagra. C'est suisse, et tres, tres precis." |
#18
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Bourns Pot Shafts Not Long Enough!
Paul wrote:
I have ordered a few of the 2K Bourns pots, with the intention of taking apart one of them, and seeing if I can replace the too-short new shaft, with the older, but longer shaft. ** That seems worth a try. It might work. If it doesn't, I'll just cut a slot in the shaft, and use a screwdriver to adjust it, as has been suggested. ** Once came across some fancy pots that uses 1/8inch metal shafts - but original knobs were missing. So, I converted /4 inch, plastic knitting needles into sleeves by drilling 1/8 inch holes up the centre of a few short pieces. Standard knobs then fitted fine. ..... Phil |
#19
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Bourns Pot Shafts Not Long Enough!
On 10/13/2018 5:17 PM, Scott Dorsey wrote:
In article , Paul wrote: No, you are misunderstand the situation. With the wiper and shaft taken off, there are two traces on the pot: one trace for the variable resistance, and one trace for the center pin. The trace for the center pin is NOT connected to pin 2. Right. There is a contact connected to the center pin which touches that trace. But the contact is bad, or that trace is dirty. Sometimes instead of having that second trace, there is a contact that connects to the side of the rotating shaft in order to provide the connection to the sliding element. Remember: the sliding element moves, the pin is static. Therefore there is a moving contact between the two. Moving contacts go bad. There is an open there, and it's somewhere embedded inside the plastic moulding. There's nothing I can do with it, without destroying it. There's an open there. Flood it with cramolin. Get cramolin behind the plastic molding. Everything that moves, get cramolin on it. Just pump it full until it comes squirting out. You can usually do this without taking the pot apart. What you are describing is one of the more common pot failure modes. No, there's nothing more can do at this point, which is why I ordered new pots. Look at this pic: https://encrypted-tbn0.gstatic.com/i...NGiz_quRoJu2nQ See the center ring? That's supposed to be connected to the center pin. In my case, it's an open, and unlike this picture, the trace disappears into the plastic moulding. The ring itself is clean, and has good continuity, but there is an open EMBEDDED INSIDE THE PLASTIC. I could try to break the plastic apart, but then the whole thing will be toast! I think my chances are decent, to replace a new shaft with the old one. |
#20
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Bourns Pot Shafts Not Long Enough!
In article , Paul wrote:
https://encrypted-tbn0.gstatic.com/i...NGiz_quRoJu2nQ See the center ring? That's supposed to be connected to the center pin. In my case, it's an open, and unlike this picture, the trace disappears into the plastic moulding. The ring itself is clean, and has good continuity, but there is an open EMBEDDED INSIDE THE PLASTIC. I could try to break the plastic apart, but then the whole thing will be toast! This is typical construction; there is a rivet used to make the connection betwen the phenolic board and the pin. What happens is that the rivet contact corrodes and becomes open. Guess what you can do in order to clean that up? Just because the contact is embedded in the plastic doesn't mean it can't be cleaned up. --scott -- "C'est un Nagra. C'est suisse, et tres, tres precis." |
#21
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Bourns Pot Shafts Not Long Enough!
On 10/15/2018 6:48 AM, Scott Dorsey wrote:
In article , Paul wrote: https://encrypted-tbn0.gstatic.com/i...NGiz_quRoJu2nQ See the center ring? That's supposed to be connected to the center pin. In my case, it's an open, and unlike this picture, the trace disappears into the plastic moulding. The ring itself is clean, and has good continuity, but there is an open EMBEDDED INSIDE THE PLASTIC. I could try to break the plastic apart, but then the whole thing will be toast! This is typical construction; there is a rivet used to make the connection betwen the phenolic board and the pin. What happens is that the rivet contact corrodes and becomes open. Guess what you can do in order to clean that up? Just because the contact is embedded in the plastic doesn't mean it can't be cleaned up. I have tried flooding it with contact cleaner, and still no go. Contact cleaner is NOT going to bridge an open gap between conductors. There are limits! But it's a moot point now....New pots from Mouser! |
#22
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Bourns Pot Shafts Not Long Enough!
On 16/10/2018 2:48 AM, Scott Dorsey wrote:
In article , Paul wrote: https://encrypted-tbn0.gstatic.com/i...NGiz_quRoJu2nQ See the center ring? That's supposed to be connected to the center pin. In my case, it's an open, and unlike this picture, the trace disappears into the plastic moulding. The ring itself is clean, and has good continuity, but there is an open EMBEDDED INSIDE THE PLASTIC. I could try to break the plastic apart, but then the whole thing will be toast! This is typical construction; there is a rivet used to make the connection betwen the phenolic board and the pin. What happens is that the rivet contact corrodes and becomes open. Guess what you can do in order to clean that up? Just because the contact is embedded in the plastic doesn't mean it can't be cleaned up. --scott I've had luck (luck that it 'took') simply flowing solder from the rivet to the metalised track. Should conside that as short-term relief only, and may or may not work with some makes of pot. geoff |
#23
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Bourns Pot Shafts Not Long Enough!
On Tue, 16 Oct 2018 07:54:47 +1300, geoff
wrote: On 16/10/2018 2:48 AM, Scott Dorsey wrote: In article , Paul wrote: https://encrypted-tbn0.gstatic.com/i...NGiz_quRoJu2nQ See the center ring? That's supposed to be connected to the center pin. In my case, it's an open, and unlike this picture, the trace disappears into the plastic moulding. The ring itself is clean, and has good continuity, but there is an open EMBEDDED INSIDE THE PLASTIC. I could try to break the plastic apart, but then the whole thing will be toast! This is typical construction; there is a rivet used to make the connection betwen the phenolic board and the pin. What happens is that the rivet contact corrodes and becomes open. Guess what you can do in order to clean that up? Just because the contact is embedded in the plastic doesn't mean it can't be cleaned up. --scott I've had luck (luck that it 'took') simply flowing solder from the rivet to the metalised track. Should conside that as short-term relief only, and may or may not work with some makes of pot. geoff Sometimes conductive paint works to repair this issue. |
#24
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Bourns Pot Shafts Not Long Enough!
On 10/15/2018 12:17 PM, Chuck wrote:
On Tue, 16 Oct 2018 07:54:47 +1300, geoff wrote: On 16/10/2018 2:48 AM, Scott Dorsey wrote: In article , Paul wrote: https://encrypted-tbn0.gstatic.com/i...NGiz_quRoJu2nQ See the center ring? That's supposed to be connected to the center pin. In my case, it's an open, and unlike this picture, the trace disappears into the plastic moulding. The ring itself is clean, and has good continuity, but there is an open EMBEDDED INSIDE THE PLASTIC. I could try to break the plastic apart, but then the whole thing will be toast! This is typical construction; there is a rivet used to make the connection betwen the phenolic board and the pin. What happens is that the rivet contact corrodes and becomes open. Guess what you can do in order to clean that up? Just because the contact is embedded in the plastic doesn't mean it can't be cleaned up. --scott I've had luck (luck that it 'took') simply flowing solder from the rivet to the metalised track. Should conside that as short-term relief only, and may or may not work with some makes of pot. geoff Sometimes conductive paint works to repair this issue. Either solder or conductive paint will not work in this case. Again, my case is different than the photo I posted, as the trace and the center pin connection is embedded within the plastic housing of the pot. I could conceivably break open the casing, but then the pot would be destroyed! So brand new post are on the way from Mouser. |
#25
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Bourns Pot Shafts Not Long Enough!
On 10/15/2018 7:02 PM, Paul wrote:
On 10/15/2018 12:17 PM, Chuck wrote: On Tue, 16 Oct 2018 07:54:47 +1300, geoff wrote: On 16/10/2018 2:48 AM, Scott Dorsey wrote: In article , Paul wrote: https://encrypted-tbn0.gstatic.com/i...NGiz_quRoJu2nQ Â*Â*Â*Â*Â*Â* See the center ring?Â* That's supposed to be connected to the center pin.Â* In my case, it's an open, and unlike this picture, the trace disappears into the plastic moulding. Â*Â*Â*Â*Â*Â* The ring itself is clean, and has good continuity, but there is an open EMBEDDED INSIDE THE PLASTIC.Â* I could try to break the plastic apart, but then the whole thing will be toast! This is typical construction; there is a rivet used to make the connection betwen the phenolic board and the pin.Â* What happens is that the rivet contact corrodes and becomes open.Â* Guess what you can do in order to clean that up? Just because the contact is embedded in the plastic doesn't mean it can't be cleaned up. --scott I've had luck (luck that it 'took') simply flowing solder from the rivet to the metalised track. Should conside that as short-term relief only, and may or may not work with some makes of pot. geoff Sometimes conductive paint works to repair this issue. Â*Â*Â*Â* Either solder or conductive paint will not work in this case.Â* Again, my case is different than the photo I posted, as the trace and the center pin connection is embedded within the plastic housing of the pot. Â*Â*Â*Â* I could conceivably break open the casing, but then the pot would be destroyed! Â*Â*Â*Â* So brand new post are on the way from Mouser. Brand new POTS are on the way! |
#26
Posted to rec.audio.pro
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Bourns Pot Shafts Not Long Enough!
On 10/15/2018 7:03 PM, Paul wrote:
On 10/15/2018 7:02 PM, Paul wrote: On 10/15/2018 12:17 PM, Chuck wrote: On Tue, 16 Oct 2018 07:54:47 +1300, geoff wrote: On 16/10/2018 2:48 AM, Scott Dorsey wrote: In article , Paul wrote: https://encrypted-tbn0.gstatic.com/i...NGiz_quRoJu2nQ Â*Â*Â*Â*Â*Â* See the center ring?Â* That's supposed to be connected to the center pin.Â* In my case, it's an open, and unlike this picture, the trace disappears into the plastic moulding. Â*Â*Â*Â*Â*Â* The ring itself is clean, and has good continuity, but there is an open EMBEDDED INSIDE THE PLASTIC.Â* I could try to break the plastic apart, but then the whole thing will be toast! This is typical construction; there is a rivet used to make the connection betwen the phenolic board and the pin.Â* What happens is that the rivet contact corrodes and becomes open.Â* Guess what you can do in order to clean that up? Just because the contact is embedded in the plastic doesn't mean it can't be cleaned up. --scott I've had luck (luck that it 'took') simply flowing solder from the rivet to the metalised track. Should conside that as short-term relief only, and may or may not work with some makes of pot. geoff Sometimes conductive paint works to repair this issue. Â*Â*Â*Â*Â* Either solder or conductive paint will not work in this case.Â* Again, my case is different than the photo I posted, as the trace and the center pin connection is embedded within the plastic housing of the pot. Â*Â*Â*Â*Â* I could conceivably break open the casing, but then the pot would be destroyed! Â*Â*Â*Â*Â* So brand new post are on the way from Mouser. Â*Â*Â*Â* Brand new POTS are on the way! It worked! I was able to disassemble one of the new 2K Bourns pots that I got from Mouser, and the old, long shaft fit perfectly! Thank god they kept the same footprint and shaft dimensions! Listen to Dark side of the moon, with my "new" speakers! Thanks for the feedback, everyone! |
#27
Posted to rec.audio.pro
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Bourns Pot Shafts Not Long Enough!
On 20/10/2018 3:58 PM, Paul wrote:
On 10/15/2018 7:03 PM, Paul wrote: On 10/15/2018 7:02 PM, Paul wrote: On 10/15/2018 12:17 PM, Chuck wrote: On Tue, 16 Oct 2018 07:54:47 +1300, geoff wrote: On 16/10/2018 2:48 AM, Scott Dorsey wrote: In article , Paul wrote: https://encrypted-tbn0.gstatic.com/i...NGiz_quRoJu2nQ Â*Â*Â*Â*Â*Â* See the center ring?Â* That's supposed to be connected to the center pin.Â* In my case, it's an open, and unlike this picture, the trace disappears into the plastic moulding. Â*Â*Â*Â*Â*Â* The ring itself is clean, and has good continuity, but there is an open EMBEDDED INSIDE THE PLASTIC.Â* I could try to break the plastic apart, but then the whole thing will be toast! This is typical construction; there is a rivet used to make the connection betwen the phenolic board and the pin.Â* What happens is that the rivet contact corrodes and becomes open.Â* Guess what you can do in order to clean that up? Just because the contact is embedded in the plastic doesn't mean it can't be cleaned up. --scott I've had luck (luck that it 'took') simply flowing solder from the rivet to the metalised track. Should conside that as short-term relief only, and may or may not work with some makes of pot. geoff Sometimes conductive paint works to repair this issue. Â*Â*Â*Â*Â* Either solder or conductive paint will not work in this case.Â* Again, my case is different than the photo I posted, as the trace and the center pin connection is embedded within the plastic housing of the pot. Â*Â*Â*Â*Â* I could conceivably break open the casing, but then the pot would be destroyed! Â*Â*Â*Â*Â* So brand new post are on the way from Mouser. Â*Â*Â*Â*Â* Brand new POTS are on the way! Â*Â*Â*Â*Â* It worked!Â* I was able to disassemble one of the new 2K Bourns pots that I got from Mouser, and the old, long shaft fit perfectly!Â* Thank god they kept the same footprint and shaft dimensions! Â*Â*Â*Â*Â* Listen to Dark side of the moon, with my "new" speakers! While in a 'moon' frame of mind, try a listen to Supertramp "Some Things Never Change" . A good workout (in many different ways) for any speaker, and great music. Jack Douglas,Fred Mandel,Jay Messina on the production/engineering side. geoff |
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