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Bell System/KS RJ-11 Crimper Model?

Started by segaloco, December 07, 2023, 12:25:14 PM

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Hello folks, I've looked around a little bit and haven't drawn any leads, is there a Bell System either in-house or KS-coded, BSP-referenced modular tip crimping tool?  I've not been able to find a reference to the "standard" modular plug crimper from back in the day.  I went to finally get one from the hardware store yesterday (been doing it with a flat-head for a while) and they were all out, so I'm taking that as the prompt to bide my time and see if I can hunt down something a little closer to the source.  Thanks everyone!


Ma Bell didn't issue field forces with modular plug crimp tools but a myriad of reputable companies such as AMP offered precision crimping tools.
In fact, yesterday I came across the AMP tool that I sidelined several years ago when I put a more compact (and cheaper) crimping tool in my mod. plug field repair kit.
 But I'm sure that the primary reason that Bell decided not to make them available to their first-level techs is because it would be much more economical to simply replace a cheap cord than to equip hundreds-of-thousands of field techs (during that period, Bell was the largest employer in the world with over one-million on the payroll) with crimp tools, when at that at the time, they cost over $100.00 for each tool and accompanying dies.
Then factor in the employees time in gathering the tool along with the correct plug, the stocking cost and the tech correctly orientating and crimping it, so a costly $40.00 (back then) callback in the future would not be necessary.
 Sure it's doable but it sure is lot cheaper to use a .25-cent mod. cord that you need to stock anyway, and is a lot simpler, more consistently accurate, and takes less time and effort. And that was the point of the modular program, to alleviate the cost of expensive repairs. In some cases, Bell would respond to a customer's complaint by mailing them the cord so they could replace it themselves.
Now days you can find modular plugs and crimp tools that are much less expensive, at large home improvement retailers such as Home Depot and Lowes, as well as many smaller hardware and electronic stores.


Fantastic background G-Man, I had a creeping suspicion that this was the case, that a whole new cord was preferred to outfitting folks with the tools to repair them in the field.  I take it then the WECo factories themselves had large apparatus that would be fitted with a die for the tip in question and would stamp them en-masse, but maybe not a standard hand tool for the same purpose.

For the record the closest thing I have found to a Bell-adjacent modular plug crimper is one sold under the Southwestern Bell business, but of course that post-dates the WECo period by some time.  Said crimpers are obviously cheap plastic and probably share zero design "DNA" with whatever dies and tools did find use in WECo factories and specialty applications.  I'm iffy on linking to offsite content because links change, but a quick Google of "Southwestern Bell crimper" should turn up what I'm talking about.


IIRC Western Electric commissioned Stewart Stamping to manufacture the initial batches of modular plugs and jack inserts. WECo then took over much of manufacturing but still retained Stewart to supply a portion of production of modular plugs and that is why you are likely to see tiny S.S. or W.E. letters on the plugs of early modular cords. I'm not positive but ISTR that in those early years AMP was also involved.

Here are a couple of links to a modular crimp tool frame ($161.67) and accompanying die set ($50.02) that are currently manufactured by Stewart:



Well that clears that up, I had seen a few references online to Stewart Stamping with regards to these tips, but I couldn't find anything that made that connection, that they were the ones subcontracted by WECo for this.  Funny too, it was spotting the "WE" on the tab of a handset plug that prompted me to do a bit more research on the production history of these tips.  Thanks for the insights G-Man, I certainly feel more informed now.


You're welcome but that is from a guy that thought last Sunday was December 7th and posted several pieces in observance of the attack on Pearl Harbor, so as usual, it may be subject to correction by others who enjoy a better memory than I do.
At least I'm not running for a political office;-)


Bell did  use  a crimper for B connectors made by CMP . CMP did make a crimping tool with interchangable dies for the different modular plugs  .It was based on the same mechanism. It might be possible .Field repairs to modular plugs can result in reversed polarity if you do not watch  how you insert the wires.