I am working on making a line of special crimp plugs that interface with a 4 pin SH style plug. This crimp plug is being designed to allow it to be crimped onto a 3 silicone covered wire strand. I wont go into the reason why here, so this blog topic will cover the projects progress.
So lets start off with a CAD view of how it might look:
The above three wires have an inner core of around .8mm and an OD of 2.3mm.
At the moment, I am exploring using some phosphor bronze prongs to skewer the wire sheath, and embed into the multi strand wire cores. These prongs and the 4 wire SH plug will be mounted onto a small PCB board:
and will maybe look something like this:
Crimp Plug
Re: Crimp Plug
Initially I looked at how a RJ45 network crimp plug worked and I disassembled a few of them to extract the gold plated metal crimp teeth. I tried trimming them down to a smaller size, but that didn't work very well. After a chat with SW Maker member on some different production methods, I ordered some phosphor brinze sheet and while waiting for that to arrive, had a go at etching some crimp teeth out of brass.
I used Designspark Mechanical CAD package to quickly draw up a single 3mm tall x1.5mm wide crimp tooth and used Inkscape to replicate and add on a attachment frame:
I used a laser/paint masking system http://forum.swmakers.org/viewtopic.php?f=12&t=186 and etch 12 teeth out of 0.2mm thick brass:
Above, some of the teeth fell off while I cleaned off the black masking paint using acetone. Below, is just a production prototype and is not meant to be functional. To give you an idea of size, the PCB is 0.8mm thick and the PCB is quite a bit smaller than a 5 cent piece:
I used Designspark Mechanical CAD package to quickly draw up a single 3mm tall x1.5mm wide crimp tooth and used Inkscape to replicate and add on a attachment frame:
I used a laser/paint masking system http://forum.swmakers.org/viewtopic.php?f=12&t=186 and etch 12 teeth out of 0.2mm thick brass:
Above, some of the teeth fell off while I cleaned off the black masking paint using acetone. Below, is just a production prototype and is not meant to be functional. To give you an idea of size, the PCB is 0.8mm thick and the PCB is quite a bit smaller than a 5 cent piece:
Re: Crimp Plug
So, how does this all look like in real life? Below is are some 3D printed examples of the crimp housing. In reality, I think it will have to be a bit bigger, and a bit taller, as it has to house the 0.8mm thick PCB.
Two half's of the crimp plug - yes, the plug and wiring is keyed, so it can only go on in one direction:
and how it might look when it's crimped into place:
Two half's of the crimp plug - yes, the plug and wiring is keyed, so it can only go on in one direction:
and how it might look when it's crimped into place:
Re: Crimp Plug
Had a go at etching out some of the crimp teeth out of 0.2mm thick phosphor bronze sheet. Luckily I tried to etch out two plates of 24 teeth. After some five hours and late at night, I took a peek, and it looked like they where done, so I pulled one out and cleaned it up to find that it was nearly done. I left the other one in for an extra 45 minutes:
There was significant undercut and the masked teeth where placed too close together for the etchant to get in properly to the metal:
0.2mm thick doesn't sound like much, but it's kind of cool to see close up of the partial etch process:
It would be handy to be able to mask and etch both sides of the sheet, but I struggle to correctly register the mask during the laser process.
There was significant undercut and the masked teeth where placed too close together for the etchant to get in properly to the metal:
0.2mm thick doesn't sound like much, but it's kind of cool to see close up of the partial etch process:
It would be handy to be able to mask and etch both sides of the sheet, but I struggle to correctly register the mask during the laser process.