Connectors?



  • In my opinion, crimpers are kind of a "minimum entry cost" to building your own 3D printer from scratch. It's a reasonable expectation for anybody buying a bare control board to have the capability to do basic wire termination.

    I do like the screw terminal idea, if it fits in the envelope for all the connectors.

    I also really like what Inventables does – they sell a low-cost crimper ($22) that matches the crimps and crimp/connector kits they sell. Very convenient.


  • administrators

    @RCarlyle:

    Thanks, I'll order a set.

    What would be REALLY slick is if you could find some way to avoid needing to crimp wires at all. I know having everything on screw terminals isn't practical, but I hate having to spend an entire evening crimping all these fragile little 24-28ga wires every time I swap boards or build a new printer. Newbies probably shouldn't be trusted with crimpers at all. Dunno what the solution is.

    Most electronics seem to use either the same Molex connectors that we use (e.g. Smoothieboard I think) or 0.1 inch Dupont connectors (e.g. RAMPS). To some extent these are interchangeable. The Dupont shells will fit the Molex headers, and Molex shells will fit Dupont headers if there is enough clearance around the header. In the case of the endstop connectors the pinouts are sometimes different, in which you need to remove pins from the shell and re-insert them in the right places - but that isn't difficult. So you shouldn't need to use re-do most of the wires when swapping between boards. For long-term use we recommend the Molex shells over the Dupont ones, because they lock in place.



  • Yeah, that's exactly what I did to get this board installed. RADDS uses non-locking 0.1" headers so I just moved around the crimps in the shells to suit the Duet, and plugged the Dupont shells into the Molex headers. But I had to terminate the fan wiring since RADDS has screw terminals for fans.

    Yes, Smoothieboards also use KK, and come to think if it I probably do have some leftover shells and crimps in a parts box somewhere.

    I'll switch to the proper KK connectors when I (eventually) shorten up the excess wiring length and clean everything up.



  • I prefer the connectors that Ultimachine provides over both of the two. I haven't had good experiences with the molex ones. IME the crimps on those are easier to break or otherwise mess up than the other ones. They also seem to be more prone to coming loose.



  • Unless you are getting cheap knock-offs, I doubt the molex crimps are sub-par. Are you using a quality, ratcheting crimp tool?



  • Its more when I have to take the crimps out of the connector that they break. I haven't used the molex connectors since I worked with a sanguinololu. I wasn't the one to build the printers that used them, so whoever did crushed the crimps on with pliers (I had to take them out to redo them, and the small locking pin would often get crushed inwards vs spring back, and it broke off more often than the locking pin on the other connectors I've used). I don't have a real nice crimping tool (its an $8 one from radioshack) but once I figured out how to use it it actually works pretty well. I haven't had any problems with using it on the smaller crimps that ultimachine includes.

    I'm not sure where the connectors were sourced, they came with the board, and I didn't buy the board (had nothing but problems with all the sanguinololus I've used, related to flashing the board/design of the board.)



  • That style Ultimachine is selling is pretty good, it's basically the same as the standard Dupont 0.1" housings but with locking tabs. I also like Molex KK though.

    My only real problem with the Dupont style is the variability of fit. If you get smallish header pins (like RADDS comes with) and largish female crimps, it ends up super loose and there isn't much you can do about it.


  • administrators

    I find it much easier to remove pins from the Molex shells than from the Dupont shells. I also find that the Molex crimp connections are 100% reliable, whereas with Dupont crimps I get the occasionally invisible bad crimp connection. But that may just mean that my crimp tool fits the Molex crimp pins better.



  • @dc42:

    They are Molex KK connectors. The shells are part number 22-01-20x4 where X is the number of pins, and the crimp pins are 08-50-0032. Compatible JST connectors are also available.

    Does someone have the DigiKey links for these parts handy? I'm not coming up with an "20x4" variant - only "20x7". Maybe my DigiKey foo is not up to the task today 😞

    Also, in addition to including a connectors kit with the boards, it would be really handy if folks that sold the boards also offered bulk packs of the connectors. It would be nice to be able to pick up extras at the same time as ordering boards & other parts.

    Thanks!
    Ian


  • administrators

    I'm sorry, I got a digit wrong, it should have been 22-01-20x5 not 20x4.

    Edit: here is the 4-way shell on Digikey: http://www.digikey.com/product-search/en?keywords=22-01-2045


  • administrators

    @ianlee74:

    Also, in addition to including a connectors kit with the boards, it would be really handy if folks that sold the boards also offered bulk packs of the connectors. It would be nice to be able to pick up extras at the same time as ordering boards & other parts.
    Ian

    Hi Ian

    If you would like an additional batch of connectors then drop us an email with what you had in mind and we can invoice you (won't be much) so that they go with your order.

    I will discuss with Roland about the logistical hassle of adding bulk connector packs as an additional stock item. It would save on delivery but it does add a bit of a picking and packing task for a very low value set.

    Cheers

    Tony




  • administrators

    @T3P3Tony:

    @ianlee74:

    Also, in addition to including a connectors kit with the boards, it would be really handy if folks that sold the boards also offered bulk packs of the connectors. It would be nice to be able to pick up extras at the same time as ordering boards & other parts.
    Ian

    Hi Ian

    If you would like an additional batch of connectors then drop us an email with what you had in mind and we can invoice you (won't be much) so that they go with your order.

    I will discuss with Roland about the logistical hassle of adding bulk connector packs as an additional stock item. It would save on delivery but it does add a bit of a picking and packing task for a very low value set.

    Cheers

    Tony

    How about adding "Additional Duet accessory kit" as a stock item?



  • Thanks, David. Good to know my Digikey foo isn't as bad as I suspected.

    Ian

    @dc42:

    I'm sorry, I got a digit wrong, it should have been 22-01-20x5 not 20x4.

    Edit: here is the 4-way shell on Digikey: http://www.digikey.com/product-search/en?keywords=22-01-2045



  • I used these KF2510 connectors from Aliexpress (4-pin, 3-pin, 2-pin)… they are supplied with crimping terminals and exactly the same as Molex KK.

    There are cheaper sets, but I can't confirm their quality.



  • Hello,

    What is the male connector reference for the extansion board, i plan to wire my external driver to it but i only find some connector with ribon cable.

    Thanks !


  • administrators



  • Some motors and printer kits come with JST XH style connectors. I can tell you that if you use a dremel to sand off the JST XH locking protrusions, and switch which holes the wires are in, the JST XH will fit onto the Molex KK connector.

    But, some of you are probably cringing right now. I am too a bit. So, are there connectors you can buy to convert JST XH 2S and 3S to the appropriate Molex KK? I looked a bit and didn't see any.

    Sort of a silly issue, since I know the board comes with the pins and connectors, but I just don't trust my crimping ability. I've already sheared the wire in half a couple times. But, while that is annoying, at least you know you did it. It's invisible errors that worry me.

    James



  • Hello

    yes sand off the JST works. thanks
    now I get a new crimping tool for jst, molex kk usw….
    that looks better.

    would be nice to buy finished Molex KK to jst (6-pin) Cables (1m) for Steppers
    and 2-pin , 3-pin for other things


  • administrators

    You can buy JST to DuPont stepper cables from suppliers such as Robotdigg, and they will fit the Molex KK connectors, with the disadvantage that they are not polarised and don't lock in place. However, the pinouts of JST connectors on stepper motors are not standardised, so you may have to swap pins around in the Dupont shell like I had to.


Locked
 

Looks like your connection to Duet3D was lost, please wait while we try to reconnect.