Members Dark Ice Posted June 23, 2008 Members Share Posted June 23, 2008 I recently found one of the first cables I ever made up, my first attempt at soldering. What a mess it was inside, so I decided to redo the ends altogether. When it came time to check the cable though, I kept getting a short between pins 1 and two. Chopped off each end, had to resolder each one twice, trying to find if there was something wrong with the connectors, or if I'd melted the insulation somewhere before finally taking my meter to the wire itself with nothing connected at either end. Still getting a short In desperation I started feeling along the wire and found a couple of lumps...stripped the insulation back, and this is what I found So what gives? Is this common on cheap crap microphone cable? Is it a manufacturing defect or does the copper somehow work itself through the insulation at some point during its life? Steve. Link to comment Share on other sites More sharing options...
Members W. M. Hellinger Posted June 23, 2008 Members Share Posted June 23, 2008 this is what I found So what gives? Is this common on cheap crap microphone cable? Is it a manufacturing defect or does the copper somehow work itself through the insulation at some point during its life? I believe the problem you've encountered could be traced to the extruding process where the insulation is extruded over the conductor strands. I believe what happened is the insulation extruding "stuck" a little, and the conductors strands continued to be fed into the extruding dies... and bunched up a little when the insulation stuck. With time and use the little bit of bunched up conductor strands worked through the insulation. I've seen this a few times over the years, and I suspect it's a difficult defect to detect in manufacturing QC. Link to comment Share on other sites More sharing options...
Members dr5euss Posted June 23, 2008 Members Share Posted June 23, 2008 Maybe a thinning in the insulation? I'm not sure...I've gone through a few 1/4 inch cables just by snagging them, never experienced this Link to comment Share on other sites More sharing options...
Members Bugzie Posted June 23, 2008 Members Share Posted June 23, 2008 Hey its not a total loss ...Have you seen the price scrap copper brings these days? LOL Link to comment Share on other sites More sharing options...
Members daklander Posted June 24, 2008 Members Share Posted June 24, 2008 So, no big deal. Cut that piece out and install a couple of ends any you have a couple more "special length" cables. Link to comment Share on other sites More sharing options...
Members agedhorse Posted June 24, 2008 Members Share Posted June 24, 2008 Possible the cable got crushed? Link to comment Share on other sites More sharing options...
Members W. M. Hellinger Posted June 24, 2008 Members Share Posted June 24, 2008 Maybe a thinning in the insulation? No, I don't think so. I believe the failure was due to bunching of the conductor strands during the insulation extrusion process when the cable was manufactured. For what little I know about cable manufacturing, extruding the insulation over the conductor is more of an art than a science. It's a continuious process, and it takes possibly a few hundred feet of spoiled cable when first starting the machinery before the proper temperature, pressure, and speed is dialed in for the PVC type being used. From what I understand it's the operator's call of when everything's right and when to make the switch from extruding cable to the spoil (recycle) bin and switch to spooling specification compliant cable. This process can't be stopped to check and then re-started... because then the operator has to go through the start-up proceedure all-over. Generally the sort of hick-up discovered by Dark Ice is from an spool that was started before the process was running smooth, or the press operator was pushing the process too fast, worn or damaged dies, or something gummed the works. Usually when this happens it's not an isolated incident and the machinery will produce and endless stream of goobered cable if the fault condition isn't corrected... but usually a systemic problem is caught and that affected cable goes into the recycle bin. An isolated incident that isn't systemic, but rather is a mid run fluke like that which Dark Ice documented is rare, but it exists occasionally. Link to comment Share on other sites More sharing options...
Members Dark Ice Posted June 25, 2008 Author Members Share Posted June 25, 2008 I reckon those two lumps I found in the cable were the only ones and it tests good now, so as long as it was only a manufacturing thing...hopefully!!!!!...this wont happen again Thanks for the insight. I now have a lovely 10' microphone lead :s and some offcuts I guess I'll use to make a Y lead or something, lol. Its good to know that this is indeed a rare occurance, and how bad this cable is to wrap has already scarred me for life from buying more cheap ass mic cable. Live and learn. Steve. Link to comment Share on other sites More sharing options...
Members W. M. Hellinger Posted June 25, 2008 Members Share Posted June 25, 2008 Its good to know that this is indeed a rare occurance, Yes, it's a very rare occurance with good cable. If there's two extrusion jams apparent on one cable, that's a common occurance of an otherwise extremely rare occurance, and is indicitive of absolutely crap cable... or an early spooling of the run (a 1 in a million anolomy or a 10 out of 10 common occurance). I'll suggest that based on your winning (or loosing as the case may be) of the cable extrusion bunching lottery twice with one cable... I'd be extremely suspect of all cabling bearing that trademark... unless the supplier gets to the bottom of the problem and replaces all cabling that might be from that batch. Link to comment Share on other sites More sharing options...
Recommended Posts
Archived
This topic is now archived and is closed to further replies.