corpse
Well-known member
- Joined
- Jun 9, 2007
- Messages
- 4,876
I don’t want to go too far back in the process- at one point the copper can splash like bath water- but all wire is made with a mechanical drawing process. It starts at 8mm and is successively run through dies making it smaller and smaller.
Easy, right? No magic or madgick?
Back in the US in the 50’s quality all hinges on the wariness of the guy in the shop- this largely precedes any serious process control in the us. Tooling wears and suddenly there is an increase in the diameter. Not a huge deal- but this stuff is running at 1000 ft per minute ( that is a guess- now about 5000 ft per minute) and was probably only changed at the start of a run- and these shops are not doing custom made wire, they are building for the DC motor industry- so they run the heck out of it. How many feet of #42 wire do you get out of an 8mm rod that starts off at 10000 ft in the basket? ( called a stem BTW- no idea why). And what about the annealing controls- if it was run too hot it may have been soft and stretched? And setting up the entire machine is a decided and expensive trick. So they take the 8mm rod and butt weld the lengths together.
https://www.123rf.com/photo_100758930_coil-of-8-mm-electrolytic-tough-pitch-copper-wire-rod-.html
The diameter is .0026” - there is a huge DCR impact by a very small change in diameter.
So in the late ‘60’s someone at Toyota created SPC and it caught on. Folks realized how much of their bottom line was being impacted by that guy in the shop not regularly measuring and charting the wire OD. And the motor manufacturers, who were being invoiced by weight, didn’t want to pay for linear feet they weren’t getting ( as it gets thicker the weight per foot goes up).
And no motor wire shop worth their salt would have cared about Gibson’s magnet wire business to run a special wire- with the cost of a set up, they couldn’t charge enough to make it remotely practical. My thought- go find some old Siemens or better, General Electric or Dodge or Rockwell motors- and salvage the wire.
Easy, right? No magic or madgick?
Back in the US in the 50’s quality all hinges on the wariness of the guy in the shop- this largely precedes any serious process control in the us. Tooling wears and suddenly there is an increase in the diameter. Not a huge deal- but this stuff is running at 1000 ft per minute ( that is a guess- now about 5000 ft per minute) and was probably only changed at the start of a run- and these shops are not doing custom made wire, they are building for the DC motor industry- so they run the heck out of it. How many feet of #42 wire do you get out of an 8mm rod that starts off at 10000 ft in the basket? ( called a stem BTW- no idea why). And what about the annealing controls- if it was run too hot it may have been soft and stretched? And setting up the entire machine is a decided and expensive trick. So they take the 8mm rod and butt weld the lengths together.
https://www.123rf.com/photo_100758930_coil-of-8-mm-electrolytic-tough-pitch-copper-wire-rod-.html
The diameter is .0026” - there is a huge DCR impact by a very small change in diameter.
So in the late ‘60’s someone at Toyota created SPC and it caught on. Folks realized how much of their bottom line was being impacted by that guy in the shop not regularly measuring and charting the wire OD. And the motor manufacturers, who were being invoiced by weight, didn’t want to pay for linear feet they weren’t getting ( as it gets thicker the weight per foot goes up).
And no motor wire shop worth their salt would have cared about Gibson’s magnet wire business to run a special wire- with the cost of a set up, they couldn’t charge enough to make it remotely practical. My thought- go find some old Siemens or better, General Electric or Dodge or Rockwell motors- and salvage the wire.