cvoinescu wrote:Molex make a gigantic, truly humongous range of connectors. Which one are you enthusiastic about?
I purchased these part numbers from Mouser (discovered the part numbers on the Ord Bot Wiki wiring page- (
http://www.buildlog.net/wiki/doku.php?id=ord:wiring):
538-43030-0001 Female crimp pin
538-43031-0001 Male crimp pin (hint - order at least 100 to save 75% on the cost)
538-43025-0400 Male 4 position Molex connecter
538-43020-0401 Female 4 position Molex connecter
538-43645-0200 Male 2 position Molex connecter
538-43640-0201 Female 2 position Molex connecter
571-876663 Female single position MOD pin (for plugging individual wires onto a header on a PCB)
I didn't purchase the plastic connecter for the female single pin. I plan on just covering it up with heat shrink tubing after crimping it. I am planning on using these to connect the limit switch wires to the PCB limit switches that were included in my Ord Bot kit from RRP.
(Don't pay any attention to the pictures on the individual Mouser page for each item as the pictures are generic and do not represent the number of positions accurately.)
I purchased this crimper from Pololu:
http://www.pololu.com/catalog/product/1928I almost wish I had followed Bart's recommendation on the wiring page and splurged for the actual Molex branded crimp tool off of eBay. The pololu crimpers are a good value. If I find I am doing a lot of small gauge wiring on other electronic kits in the future I will probably sell these and splurge for the Molex crimpers. Don't get me wrong, the one from Pololu does a great job but it is absolutely critical that you place the wire and crimp pin perfectly in the crimper for it to work. It only took me a couple of crimps before I learned exactly how to place the pin in the crimper. I watched this video about how to use these crimpers and it helped me a lot:
https://www.youtube.com/watch?v=GkbOJSvhCgU These crimpers do work really well but it just takes a lot of attention to detail to get the crimp right. I am a big believer in buying what you want the first time where tools are concerned and I have read that getting a perfect crimp is much easier with the Molex branded crimp tool.
cvoinescu wrote:There shouldn't be any serious issues with unshielded cable. If anything, I'd use shielded wire for the limit switch connections. The heaters couldn't care less, and the thermistors have large filter caps so they should be fine. Still, if you're concerned about generating interference, it helps a lot if you twist all four wires for one motor together. Don't braid them, twist them -- easy to do if all four wires are loose at one end, nearly impossible if both ends are connected -- and keep in mind that you lose a little length when twisting them.
Thanks for the info on the wiring. I am going to take your advice and use the silicone wiring for the motors & shielded for the limit switches. I will also twist the wires before putting them in the braided wire sleeves.
I will post some pictures tomorrow of my progress. I need to get a build log started.