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Electronics Repair (sci.electronics.repair) Discussion of repairing electronic equipment. Topics include requests for assistance, where to obtain servicing information and parts, techniques for diagnosis and repair, and annecdotes about success, failures and problems. |
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#1
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Obviously I've come acros melting/burning, starting from bad connection
arcing , but not this amount of damage, so am requesting other opinions. A superfluity of mains fuses all ok, on 240V UK mains, 5 amp in plug, 4 amp chassis mounted and internal 5 amp all in series. Mains transformer seems right sort of primary and secondary resistance. All other internal fuses ok and no other visually obvious problems. Burning right thru the pcb for 1/2 inch around the L pin of the IEC, melting of the plastic of the IEC above the burning and even the linecord plug surrounding the L pin melting where heat conducted through the pin presumably. Remainder of IEC receptacle distorted from heat but holding together. The N pin soldering at the pcb is bad, but has continuity, I assume pre-existing rather than from heat damage as 3/4 inch from the main L arcing, so temp would not have reached solder melt point on the N pin. I assume the L pin solder was worse and initial cause of arcing. Amp was just idling , with no sound throughput, is that why so much damage as only tens of mA passing in the arcs. ? If 0.5 amp or more, then the damage would have been more extreme , but shorter duration, before total break in pcb track or solder joint meant a fuse action in effect, before greater heat damage could take effect. The remnant pcb charring is not obviously conductive (30 M ohm DVM) Incidently the earth pin soldering although smoke stained looks fine, coincidence? or passing of electricity have an initiation effect on good solder to become bad or does it require porous solder or something inherently bad with it for a heating effect to come into play, long before any full arcing? -- Diverse Devices, Southampton, England electronic hints and repair briefs , schematics/manuals list on http://home.graffiti.net/diverse:graffiti.net/ |
#2
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fuses are 5A mains,2AT,5AQ
after cleaning away as much grime as possible , any suggestions for disguising/absorbing the remanant pong ? |
#3
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N_Cook wrote:
Obviously I've come acros melting/burning, starting from bad connection arcing , but not this amount of damage, so am requesting other opinions. A superfluity of mains fuses all ok, on 240V UK mains, 5 amp in plug, 4 amp chassis mounted and internal 5 amp all in series. Mains transformer seems right sort of primary and secondary resistance. All other internal fuses ok and no other visually obvious problems. Burning right thru the pcb for 1/2 inch around the L pin of the IEC, melting of the plastic of the IEC above the burning and even the linecord plug surrounding the L pin melting where heat conducted through the pin presumably. Remainder of IEC receptacle distorted from heat but holding together. The N pin soldering at the pcb is bad, but has continuity, I assume pre-existing rather than from heat damage as 3/4 inch from the main L arcing, so temp would not have reached solder melt point on the N pin. I assume the L pin solder was worse and initial cause of arcing. Amp was just idling , with no sound throughput, is that why so much damage as only tens of mA passing in the arcs. ? If 0.5 amp or more, then the damage would have been more extreme , but shorter duration, before total break in pcb track or solder joint meant a fuse action in effect, before greater heat damage could take effect. The remnant pcb charring is not obviously conductive (30 M ohm DVM) Incidently the earth pin soldering although smoke stained looks fine, coincidence? or passing of electricity have an initiation effect on good solder to become bad or does it require porous solder or something inherently bad with it for a heating effect to come into play, long before any full arcing? Has someone spilled liquid into it? If you measured the resistance of the charring with low voltage, you might have had a false high reading; with 240v you could find that it flashes over or sputters badly. What would the normal running current and the maximum fault current from a shorted transformer secondary have been? A bad joint of 5k-ohms in a circuit carrying 20 mA will develop 2 watts, which is enough to char a PCB. I have come across some connector pairs purporting to be IEC-compliant, where the pins and the socket connections hardly touched. I submitted them to Trading Standards and was told that both halves did comply with the specification - so you might have come across a similar problem to that; and the fault may not be in the soldering. -- ~ Adrian Tuddenham ~ (Remove the ".invalid"s and add ".co.uk" to reply) www.poppyrecords.co.uk |
#4
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Adrian Tuddenham wrote in message
valid.invalid... N_Cook wrote: Obviously I've come acros melting/burning, starting from bad connection arcing , but not this amount of damage, so am requesting other opinions. A superfluity of mains fuses all ok, on 240V UK mains, 5 amp in plug, 4 amp chassis mounted and internal 5 amp all in series. Mains transformer seems right sort of primary and secondary resistance. All other internal fuses ok and no other visually obvious problems. Burning right thru the pcb for 1/2 inch around the L pin of the IEC, melting of the plastic of the IEC above the burning and even the linecord plug surrounding the L pin melting where heat conducted through the pin presumably. Remainder of IEC receptacle distorted from heat but holding together. The N pin soldering at the pcb is bad, but has continuity, I assume pre-existing rather than from heat damage as 3/4 inch from the main L arcing, so temp would not have reached solder melt point on the N pin. I assume the L pin solder was worse and initial cause of arcing. Amp was just idling , with no sound throughput, is that why so much damage as only tens of mA passing in the arcs. ? If 0.5 amp or more, then the damage would have been more extreme , but shorter duration, before total break in pcb track or solder joint meant a fuse action in effect, before greater heat damage could take effect. The remnant pcb charring is not obviously conductive (30 M ohm DVM) Incidently the earth pin soldering although smoke stained looks fine, coincidence? or passing of electricity have an initiation effect on good solder to become bad or does it require porous solder or something inherently bad with it for a heating effect to come into play, long before any full arcing? Has someone spilled liquid into it? If you measured the resistance of the charring with low voltage, you might have had a false high reading; with 240v you could find that it flashes over or sputters badly. What would the normal running current and the maximum fault current from a shorted transformer secondary have been? A bad joint of 5k-ohms in a circuit carrying 20 mA will develop 2 watts, which is enough to char a PCB. I have come across some connector pairs purporting to be IEC-compliant, where the pins and the socket connections hardly touched. I submitted them to Trading Standards and was told that both halves did comply with the specification - so you might have come across a similar problem to that; and the fault may not be in the soldering. -- ~ Adrian Tuddenham ~ (Remove the ".invalid"s and add ".co.uk" to reply) www.poppyrecords.co.uk Where the pins of the IEC chassis part go through the plastic there is no melting or burning but the linecord plug (softer plastic) shows signs of melting around the line pin , no burning. So the initial problem not mis-mating of IEC pins. Downstream problems , transformer, ps etc is possible I suppose , no blown fuses though. -- Diverse Devices, Southampton, England electronic hints and repair briefs , schematics/manuals list on http://home.graffiti.net/diverse:graffiti.net/ |
#5
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N_Cook wrote:
Adrian Tuddenham wrote in message valid.invalid... N_Cook wrote: Obviously I've come acros melting/burning, starting from bad connection arcing , but not this amount of damage, so am requesting other opinions. A superfluity of mains fuses all ok, on 240V UK mains, 5 amp in plug, 4 amp chassis mounted and internal 5 amp all in series. Mains transformer seems right sort of primary and secondary resistance. All other internal fuses ok and no other visually obvious problems. Burning right thru the pcb for 1/2 inch around the L pin of the IEC, melting of the plastic of the IEC above the burning and even the linecord plug surrounding the L pin melting where heat conducted through the pin presumably. Remainder of IEC receptacle distorted from heat but holding together. [...] I have come across some connector pairs purporting to be IEC-compliant, where the pins and the socket connections hardly touched. I submitted them to Trading Standards and was told that both halves did comply with the specification - so you might have come across a similar problem to that; and the fault may not be in the soldering. Where the pins of the IEC chassis part go through the plastic there is no melting or burning but the linecord plug (softer plastic) shows signs of melting around the line pin , no burning. Some of those IEC chassis connectors are almost indestructible. I have tried to melt one of the pins out of one with a soldering iron and it simply would not move. I had to tear the rivetted tag off the back with a vice, then file down the remains of the pin and punch it out. I can quite believe that the items each side could be damaged by heat but the connector in the middle would show no signs of burning. So the initial problem not mis-mating of IEC pins. Downstream problems , transformer, ps etc is possible I suppose , no blown fuses though. If the direct cause of the heat was a high resistance joint, you wouldn't expect a blown fuse. A shorted secondary on a small transformer wouldn't necessarily blow the fuse either. It has occurred to me that if a solder joint had gone high resistance, the increase in temperature would either melt it back together or blow it open before the board became damaged. I still think a poor plug/socket connection is a likely cause. -- ~ Adrian Tuddenham ~ (Remove the ".invalid"s and add ".co.uk" to reply) www.poppyrecords.co.uk |
#6
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Adrian Tuddenham wrote in message
valid.invalid... N_Cook wrote: Adrian Tuddenham wrote in message valid.invalid... N_Cook wrote: Obviously I've come acros melting/burning, starting from bad connection arcing , but not this amount of damage, so am requesting other opinions. A superfluity of mains fuses all ok, on 240V UK mains, 5 amp in plug, 4 amp chassis mounted and internal 5 amp all in series. Mains transformer seems right sort of primary and secondary resistance. All other internal fuses ok and no other visually obvious problems. Burning right thru the pcb for 1/2 inch around the L pin of the IEC, melting of the plastic of the IEC above the burning and even the linecord plug surrounding the L pin melting where heat conducted through the pin presumably. Remainder of IEC receptacle distorted from heat but holding together. [...] I have come across some connector pairs purporting to be IEC-compliant, where the pins and the socket connections hardly touched. I submitted them to Trading Standards and was told that both halves did comply with the specification - so you might have come across a similar problem to that; and the fault may not be in the soldering. Where the pins of the IEC chassis part go through the plastic there is no melting or burning but the linecord plug (softer plastic) shows signs of melting around the line pin , no burning. Some of those IEC chassis connectors are almost indestructible. I have tried to melt one of the pins out of one with a soldering iron and it simply would not move. I had to tear the rivetted tag off the back with a vice, then file down the remains of the pin and punch it out. I can quite believe that the items each side could be damaged by heat but the connector in the middle would show no signs of burning. So the initial problem not mis-mating of IEC pins. Downstream problems , transformer, ps etc is possible I suppose , no blown fuses though. If the direct cause of the heat was a high resistance joint, you wouldn't expect a blown fuse. A shorted secondary on a small transformer wouldn't necessarily blow the fuse either. It has occurred to me that if a solder joint had gone high resistance, the increase in temperature would either melt it back together or blow it open before the board became damaged. I still think a poor plug/socket connection is a likely cause. -- ~ Adrian Tuddenham ~ (Remove the ".invalid"s and add ".co.uk" to reply) www.poppyrecords.co.uk The half inch radius destruction was total , burning down to glass mat , the thickness of the board. I just cannot see that happening due to an arcing contact inside the mated plug and socket and the heat conducted through an inch or so of metal conductor , with only marginal melting to the line cord plug. Without carving into the line plug I cannot see the surface of the female part but the male pins in the chassis section show no pitting or sign of arcing. -- Diverse Devices, Southampton, England electronic hints and repair briefs , schematics/manuals list on http://home.graffiti.net/diverse:graffiti.net/ |
#7
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![]() N_Cook wrote: Without carving into the line plug I cannot see the surface of the female part but the male pins in the chassis section show no pitting or sign of arcing. If you're reading my posts ( which I doubt since you ask so many daft questions the answers to which that you ought to *know ) do these thing. Insert the apparently undamaged part into a new mating half. Does it hold firm ? Apply a serious current through each contact and measure the volt drop. That'll tell you the contact resistance from which much can be deduced. And when bands bring in gear with 'tatty' mains leads, replace them and destroy the defective one ( hand it back in a bag). They cost bugger all and could save a life. Also check the plugtop fuse rating fitted. It's easy to put a 13A fuse in the plug of a 5A lead. And VERY stupid. Graham |
#8
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![]() Adrian Tuddenham wrote: I still think a poor plug/socket connection is a likely cause. Loose contact pressure high resistance joint. I've heard of it and had it reported to me but never seen it personally. It happens when cheapskate bands treat their kit like **** and don't look after cables and their own personal safety. Graham |
#9
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Another maybe relevant factor. The IEC socket was rivetted to the pcb and
very firm but the section that is chassis mounted had much smaller diameter screws than I would normally expect. Although star washers under the nuts they undid easily. Maybe that due to the heating but also could be due to normal inserting of cord into socket straining the pcb solder connections over years of use/stowage. Would also explain why no obvious bad solder on the ground pin as that is mechanically more remote by another half inch of conductor compared to the active conductor lengths. -- Diverse Devices, Southampton, England electronic hints and repair briefs , schematics/manuals list on http://home.graffiti.net/diverse:graffiti.net/ |
#10
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![]() N_Cook wrote: Another maybe relevant factor. The IEC socket was rivetted to the pcb and very firm but the section that is chassis mounted had much smaller diameter screws than I would normally expect. Although star washers under the nuts they undid easily. Maybe that due to the heating but also could be due to normal inserting of cord into socket straining the pcb solder connections over years of use/stowage. Would also explain why no obvious bad solder on the ground pin as that is mechanically more remote by another half inch of conductor compared to the active conductor lengths. Look for the basics instead of pontificating. That's where it'll be. Getting on for 40 yrs experience tells me that. Graham |
#11
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![]() Adrian Tuddenham wrote: Has someone spilled liquid into it? If built to BSEN60065 properly it wouldn't matter. Fault currents should be dealt with by blowing fuses or adequate copper foil thickness / area to withstand the current. I'll bet some clot replaced a fuse with some ali foil. Graham |
#12
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On May 21, 2:59*am, "N_Cook" wrote:
Obviously I've come acros melting/burning, starting from bad connection arcing , but not this amount of damage, so am requesting other opinions. Burning right thru the pcb for 1/2 inch around the L pin of the IEC, melting of the plastic of the IEC above the burning and even the linecord plug Yep, ring crack around a power solder connection, generates lots of heat. If you can clean away the char, do it (I've used glass bead blasting to good effect). Paint the affected region with Q-dope/styrene varnish/corona dope when cleaning/soldering/flux cleaning is done. Replace any AC fittings that look damaged, of course. |
#13
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![]() whit3rd wrote: On May 21, 2:59 am, "N_Cook" wrote: Obviously I've come acros melting/burning, starting from bad connection arcing , but not this amount of damage, so am requesting other opinions. Burning right thru the pcb for 1/2 inch around the L pin of the IEC, melting of the plastic of the IEC above the burning and even the linecord plug Yep, ring crack around a power solder connection, generates lots of heat. Possible. A victim of lead-free soldering ? http://en.wikipedia.org/wiki/Tin_pest Note that pure tin solder degrades below 13C. Yes that's right. And turns to dust. Adding a little copper doesn't stop it but slows it some but not enough. The EU Commission should be strung by their necks from lamp-posts for being a bunch of technically ignorant ****s. Why do they think lead was used in solder in the first place ? For fun ? Graham |
#14
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![]() "Eeyore" wrote in message ... whit3rd wrote: On May 21, 2:59 am, "N_Cook" wrote: Obviously I've come acros melting/burning, starting from bad connection arcing , but not this amount of damage, so am requesting other opinions. Burning right thru the pcb for 1/2 inch around the L pin of the IEC, melting of the plastic of the IEC above the burning and even the linecord plug Yep, ring crack around a power solder connection, generates lots of heat. Possible. A victim of lead-free soldering ? http://en.wikipedia.org/wiki/Tin_pest Note that pure tin solder degrades below 13C. Yes that's right. And turns to dust. Adding a little copper doesn't stop it but slows it some but not enough. The EU Commission should be strung by their necks from lamp-posts for being a bunch of technically ignorant ****s. Why do they think lead was used in solder in the first place ? For fun ? Graham Just what I've been saying since they first mandated the hateful stuff ... Arfa |
#15
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Arfa Daily wrote in message
... "Eeyore" wrote in message ... whit3rd wrote: On May 21, 2:59 am, "N_Cook" wrote: Obviously I've come acros melting/burning, starting from bad connection arcing , but not this amount of damage, so am requesting other opinions. Burning right thru the pcb for 1/2 inch around the L pin of the IEC, melting of the plastic of the IEC above the burning and even the linecord plug Yep, ring crack around a power solder connection, generates lots of heat. Possible. A victim of lead-free soldering ? http://en.wikipedia.org/wiki/Tin_pest Note that pure tin solder degrades below 13C. Yes that's right. And turns to dust. Adding a little copper doesn't stop it but slows it some but not enough. The EU Commission should be strung by their necks from lamp-posts for being a bunch of technically ignorant ****s. Why do they think lead was used in solder in the first place ? For fun ? Graham Just what I've been saying since they first mandated the hateful stuff ... Arfa This is a 1998 amplifier, made in China so conventional solder ? does not look "volcanic" or tin-pesty dusty grey solder points on the boards. -- Diverse Devices, Southampton, England electronic hints and repair briefs , schematics/manuals list on http://home.graffiti.net/diverse:graffiti.net/ |
#16
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N_Cook wrote:
Arfa Daily wrote in message ... "Eeyore" wrote in message ... whit3rd wrote: On May 21, 2:59 am, "N_Cook" wrote: Obviously I've come acros melting/burning, starting from bad connection arcing , but not this amount of damage, so am requesting other opinions. Burning right thru the pcb for 1/2 inch around the L pin of the IEC, melting of the plastic of the IEC above the burning and even the linecord plug Yep, ring crack around a power solder connection, generates lots of heat. Possible. A victim of lead-free soldering ? http://en.wikipedia.org/wiki/Tin_pest Note that pure tin solder degrades below 13C. Yes that's right. And turns to dust. Adding a little copper doesn't stop it but slows it some but not enough. The EU Commission should be strung by their necks from lamp-posts for being a bunch of technically ignorant ****s. Why do they think lead was used in solder in the first place ? For fun ? Graham Just what I've been saying since they first mandated the hateful stuff ... Arfa This is a 1998 amplifier, made in China so conventional solder ? does not look "volcanic" or tin-pesty dusty grey solder points on the boards. It probly started off as a hairline crack around one of the soldered joins, caused by repeated connecting and disconnecting. It started 'fizzling', no one noticed (or cared) until the amp failed to work by which time there was a socking great hole in the board and a nasty smell. It`a amazing how long a lot of musicians will put up with faulty gear, prefering to ignore problems till the item stops working. Doesn't really need a post mortem. Ron(UK) |
#17
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![]() "Meat Plow" wrote in message ... On Fri, 22 May 2009 01:49:59 +0100, "Arfa Daily" wrote: "Eeyore" wrote in message ... whit3rd wrote: On May 21, 2:59 am, "N_Cook" wrote: Obviously I've come acros melting/burning, starting from bad connection arcing , but not this amount of damage, so am requesting other opinions. Burning right thru the pcb for 1/2 inch around the L pin of the IEC, melting of the plastic of the IEC above the burning and even the linecord plug Yep, ring crack around a power solder connection, generates lots of heat. Possible. A victim of lead-free soldering ? http://en.wikipedia.org/wiki/Tin_pest Note that pure tin solder degrades below 13C. Yes that's right. And turns to dust. Adding a little copper doesn't stop it but slows it some but not enough. The EU Commission should be strung by their necks from lamp-posts for being a bunch of technically ignorant ****s. Why do they think lead was used in solder in the first place ? For fun ? Graham Just what I've been saying since they first mandated the hateful stuff ... Arfa Glad I stockpiled enough 60/40 to last me a lifetime. I could probably sell it on Ebay for an exuberant price one day :-) This Tin Pest stuff sounds like a serious problem though. 60/40 is still readily available here in pretty much all of the varieties that it always was - I got a new roll just a couple of weeks ago. What was interesting though, is that they have jacked up the price to match - almost exactly - the cost of the dreaded lead-free, which up until recently, was like 50% more expensive. Arfa |
#18
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Arfa Daily wrote in message
... "Meat Plow" wrote in message ... On Fri, 22 May 2009 01:49:59 +0100, "Arfa Daily" wrote: "Eeyore" wrote in message ... whit3rd wrote: On May 21, 2:59 am, "N_Cook" wrote: Obviously I've come acros melting/burning, starting from bad connection arcing , but not this amount of damage, so am requesting other opinions. Burning right thru the pcb for 1/2 inch around the L pin of the IEC, melting of the plastic of the IEC above the burning and even the linecord plug Yep, ring crack around a power solder connection, generates lots of heat. Possible. A victim of lead-free soldering ? http://en.wikipedia.org/wiki/Tin_pest Note that pure tin solder degrades below 13C. Yes that's right. And turns to dust. Adding a little copper doesn't stop it but slows it some but not enough. The EU Commission should be strung by their necks from lamp-posts for being a bunch of technically ignorant ****s. Why do they think lead was used in solder in the first place ? For fun ? Graham Just what I've been saying since they first mandated the hateful stuff .... Arfa Glad I stockpiled enough 60/40 to last me a lifetime. I could probably sell it on Ebay for an exuberant price one day :-) This Tin Pest stuff sounds like a serious problem though. 60/40 is still readily available here in pretty much all of the varieties that it always was - I got a new roll just a couple of weeks ago. What was interesting though, is that they have jacked up the price to match - almost exactly - the cost of the dreaded lead-free, which up until recently, was like 50% more expensive. Arfa Do you know the most authorative source/group, academic or industry expert/s, on tin-pest, lead-free solder, in-service degradation of solder in connjunction with temperature and vibration. ie those issues, as distinct from tin whiskers aspect that seems to have more coverage. -- Diverse Devices, Southampton, England electronic hints and repair briefs , schematics/manuals list on http://home.graffiti.net/diverse:graffiti.net/ |
#19
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![]() "Meat Plow" wrote in message ... On Sat, 23 May 2009 02:01:09 +0100, "Arfa Daily" wrote: "Meat Plow" wrote in message ... On Fri, 22 May 2009 01:49:59 +0100, "Arfa Daily" wrote: "Eeyore" wrote in message ... whit3rd wrote: On May 21, 2:59 am, "N_Cook" wrote: Obviously I've come acros melting/burning, starting from bad connection arcing , but not this amount of damage, so am requesting other opinions. Burning right thru the pcb for 1/2 inch around the L pin of the IEC, melting of the plastic of the IEC above the burning and even the linecord plug Yep, ring crack around a power solder connection, generates lots of heat. Possible. A victim of lead-free soldering ? http://en.wikipedia.org/wiki/Tin_pest Note that pure tin solder degrades below 13C. Yes that's right. And turns to dust. Adding a little copper doesn't stop it but slows it some but not enough. The EU Commission should be strung by their necks from lamp-posts for being a bunch of technically ignorant ****s. Why do they think lead was used in solder in the first place ? For fun ? Graham Just what I've been saying since they first mandated the hateful stuff ... Arfa Glad I stockpiled enough 60/40 to last me a lifetime. I could probably sell it on Ebay for an exuberant price one day :-) This Tin Pest stuff sounds like a serious problem though. 60/40 is still readily available here in pretty much all of the varieties that it always was - I got a new roll just a couple of weeks ago. What was interesting though, is that they have jacked up the price to match - almost exactly - the cost of the dreaded lead-free, which up until recently, was like 50% more expensive. Arfa Last I bought was for copper plumbing. I tried the lead free crap and it was laughable on 1/2 inch water pipe. I have many years experience soldering and brazing but won't touch the lead free crap again. I have an acquaintance who is a plumber, and some long time ago when the stuff was first becoming mandated for electronic construction work, which was actually some time after it became so for live water systems, I asked him how he got on with it. He told me that at first they had a lot of problems getting it to 'stick' to a joint, and problems with leaks. He said that they had eventually got used to it, and that they could now make joints as good as with leaded solder. However, he said that it required rather different techniques to those conventionally used for plumbing soldering in that the surfaces to be joined must be *very* clean as opposed to just fundamentally clean, and that an aggressive flux helped. He also said that it was funny stuff to work with in that it reached its melting point very suddenly, and then had a tendency to run out of the joint, before re-setting very suddenly also, so no 'pasty' phase, which I guess would knock on the head the old technique of 'wiping' a joint. Given that copper expands very readily, it will be interesting to see if joints start breaking and leaking in 15 years' time due to the total lack of ductility that lead-free has. We've all seen the effects of rather more intense thermal cycling on the short-term integrity of electronic joints. Perhaps plumbing joints are a ticking timebomb ... :-) To N.Cook The place that I got my research material from was Tin Technology Ltd with a website of www.lead-free.org The person that I spoke to at that body, pointed me to www.dti.gov.uk/sustainability/weee/index.htm I also spoke to a Dr Goodman at ERAT Technology Ltd All of this was 3 years ago now, and I have not visited those sites since, if they still exist, but they did contain some good stuff at the time, and they might lead you where you want to go, now. Arfa Arfa |
#20
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Eeyore wrote:
The EU Commission should be strung by their necks from lamp-posts for being a bunch of technically ignorant ****s. Why do they think lead was used in solder in the first place ? For fun ? In the past I have many times agreed with your facts, but I have often disagreed with your way of expressing them. On this occasion I am with you all the way. Let's hope the first aeroplane to crash because of lead-free solder has only Brussels diplomats and anti-lead campaigners on board. -- ~ Adrian Tuddenham ~ (Remove the ".invalid"s and add ".co.uk" to reply) www.poppyrecords.co.uk |
#21
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![]() "Adrian Tuddenham" wrote in message alid.invalid... Eeyore wrote: The EU Commission should be strung by their necks from lamp-posts for being a bunch of technically ignorant ****s. Why do they think lead was used in solder in the first place ? For fun ? In the past I have many times agreed with your facts, but I have often disagreed with your way of expressing them. On this occasion I am with you all the way. Let's hope the first aeroplane to crash because of lead-free solder has only Brussels diplomats and anti-lead campaigners on board. -- ~ Adrian Tuddenham ~ (Remove the ".invalid"s and add ".co.uk" to reply) www.poppyrecords.co.uk As far as I know, at this point in time, the avionics industry still has an exemption from having to use the stuff. Now I wonder why that could be ... ? Arfa |
#22
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Arfa Daily wrote:
"Adrian Tuddenham" wrote in message alid.invalid... Eeyore wrote: The EU Commission should be strung by their necks from lamp-posts for being a bunch of technically ignorant ****s. Why do they think lead was used in solder in the first place ? For fun ? In the past I have many times agreed with your facts, but I have often disagreed with your way of expressing them. On this occasion I am with you all the way. Let's hope the first aeroplane to crash because of lead-free solder has only Brussels diplomats and anti-lead campaigners on board. -- ~ Adrian Tuddenham ~ (Remove the ".invalid"s and add ".co.uk" to reply) www.poppyrecords.co.uk As far as I know, at this point in time, the avionics industry still has an exemption from having to use the stuff. Now I wonder why that could be ... ? They may be exempt, but what might they do when they can't get the proper stuff any more because no manufacturer can afford to run two production lines for the same product simultaneously and daren't risk getting them muddled? 1) Set up special production lines. 2) Stop making avionics. 3) Change the rules and use lead-free. -- ~ Adrian Tuddenham ~ (Remove the ".invalid"s and add ".co.uk" to reply) www.poppyrecords.co.uk |
#23
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Posted to sci.electronics.repair
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Arfa Daily wrote:
"Adrian Tuddenham" wrote in message alid.invalid... Eeyore wrote: The EU Commission should be strung by their necks from lamp-posts for being a bunch of technically ignorant ****s. Why do they think lead was used in solder in the first place ? For fun ? In the past I have many times agreed with your facts, but I have often disagreed with your way of expressing them. On this occasion I am with you all the way. Let's hope the first aeroplane to crash because of lead-free solder has only Brussels diplomats and anti-lead campaigners on board. -- ~ Adrian Tuddenham ~ (Remove the ".invalid"s and add ".co.uk" to reply) www.poppyrecords.co.uk As far as I know, at this point in time, the avionics industry still has an exemption from having to use the stuff. Now I wonder why that could be ... ? Medical also. -- W . | ,. w , "Some people are alive only because \|/ \|/ it is illegal to kill them." Perna condita delenda est ---^----^--------------------------------------------------------------- |
#24
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Posted to sci.electronics.repair
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![]() N_Cook wrote: Burning right thru the pcb for 1/2 inch around the L pin of the IEC, melting of the plastic of the IEC above the burning and even the linecord plug surrounding the L pin melting where heat conducted through the pin presumably. Indicates vast overcurrent. Did someone put aluminium foil in the plugtop fuse ? Typical musician practice. Graham |
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