TLDR: My custom sleeved EPS cables are complete and have been tested successfully!
Now for the longer story (because of course there's a longer story lol)...
So it's been a couple months since I've worked on my custom sleeved PSU cables, so I decided to get back into it by starting with the "easiest" task of finishing up the EPS cables (my motherboard uses two of them). All I had to do for those is cut them to length and attach the 8-pin connrectors to the PSU side of the cable. No split wires to deal with for these ones.
Sounds pretty easy, right?
Well, let's just say I was a bit rusty, and made some novice mistakes. On the first cable I actually got all the pins in the right locations and the PSU tester showed that the cable was good! But as I started the second cable I realized I did something really dumb on first cable - I inserted the second row of pins upside down (no wonder I was having so much trouble getting them in the connector...). Even though the cable tested successfully, the pins being upside down meant that they could easily some out of the connector, which would obviously be less than ideal. So I had to take those pins out, and crimp new pins facing the correct direction.
For the second cable I managed to put the pins I the correct orientation, but I put them in the completely wrong locations in the connector. I think when I was ordering the wires, I was looking at the back of the connector instead of the front. Oops. The PSU tester beeped angrily with a red backlight when I attempted to test that cable. So I figured I'd just remove the pins from the connector (I have a handy ATX pin removal tool just for this sort of occasion), reorder them, and put them back in the connector. Simple, right? Well, that didn't go quite according to plan. 3 of the pins were so stuck in the connector that the cables actually came loose from the pins and the pins stubbornly remained inside the connector. For about 30 minutes I tried my hardest to get those pins out. I tried using some tiny tweezers to grip the pin from the back and pull it out, or push it out from the front (while the pin remover tool was inserted), and nothing worked. I ended up giving up and stealing the connector from one of my stock PSU cables. Since some of the wires no longer had pins, and because I had to reorder them to their correct locations, that meant that all the cables were no longer the correct length. So I painfully had to re-trim all the cables and crimp new pins on all of them. Let's just say I've definitely learned my lesson. Next time I will double check the pin order with a multimeter before I crimp pins on them and insert them into the connector. It will save me a lot of time, frustration, and wasted pins.
Eventually I finished and thankfully it passed the PSU tester this time. As brutally honest as that PSU tester is, I was very happy I had it today. Sure I could do a continuity test with a multimeter using the pinout diagrams I wrote, but seeing the PSU tester read the correct voltage coming across that cable just gives you that extra peace of mind.
I'm hopeful that my 24-pin ATX cable and my 3 8-pin PCI-E cables will go a bit more smoothly than these did, despite the added complication of having to splice a second wire into handful of those wires. Should be fun
After making some novice mistakes, I finaly finished the PSU-side of the EPS cables. I am already starting to appreciate just how much custom length PSU cables will help with managing this rat's nest of cables.