A Crimping Tool or methods for crimping PU or LPF2 connectors.

[James_D]

I would like to make some custom length LPF2 cables using multi-colored ribbon cable to use with my SPIKE Prime Hub. I am putting alternative connections such as Dupont Header connectors at the other end of the cable for connection to breadboards and other devices. I have searched other posts on these forums but not found any good answers to the following questions:

1. Has anyone found an appropriate crimping tool for attaching the LPF2 connectors to wires?
2. In the absence of a proper crimping tool, what techniques have people used to successfully attach PU/LPF2 connectors to cables?

To speed up the responses and hopefully assist anyone else looking to doing something similar:

• I understand these are not an industry standard connector. ie they are a TLG proprietary connector
• Philo has done a great breakdown of the specifications here: https://www.philohome.com/wedo2reverse/connect.htm
• Marek has 3D printed his own solution here: https://www.biasedlogic.com/index.php/lego-powered-up-connector/
• As the TLG don't seem to provide a ready solution, on AliExpress I bought:
  • non-LEGO PU/LPF2 type connectors with metal inserts (referred to as 'Crystal Connectors' likely because they are a clear plastic)
  • The above connectors connected to 25cm of black cable at one end. https://www.aliexpress.com/i/4000183638282.html

I have made attempts to connect the non-LEGO PU/LPF2 connectors from AliExpress to some multi-colored ribbon cable (with the correct wire pitch of 1.27mm). However, at this stage I have not yet got the pressure level correct for proper crimping. When I plug the cable into a SPIKE Prime Hub, they are extremely tight to squeeze in and incredibly difficult to pull out.

I'm now considering looking to use a vice our some multigrip pliers to try crimp/attach the connectors. I am hoping someone else out there might have a more reliable/better solution.

Thanks in advance.

 

[dr_spock]

You could try carefully pressing down each pin one at a time with the correct sized flat head screwdriver in an arbor press.

 

[Jim]

You are definitely not the only one looking for this. I would love to get some cables myself.

PV productions has some, but they are rather expensive.

[dr_spock]

I have an RJ45 crimper but the pin spacing is wrong for PU. Otherwise, I could probably grind off 2 of the 8 pins on the die to make it work.  Someone should fabricate a die for the crimper.

I went the cheapskate route of 3D printing my own and epoxying the wires onto the grooves.  I have to be careful not to get epoxy on the bare wires if I want things to.powered up. 

[James_D]

1 hour ago, dr_spock said:

I have an RJ45 crimper but the pin spacing is wrong for PU. Otherwise, I could probably grind off 2 of the 8 pins on the die to make it work.  Someone should fabricate a die for the crimper.

I went the cheapskate route of 3D printing my own and epoxying the wires onto the grooves.  I have to be careful not to get epoxy on the bare wires if I want things to.powered up. 

@dr_spock Thanks for the tip on the Arbor Press, I had to look up what it was and you are correct that an Arbor Press in combination with a suitable screw driver may then help to get the internal metal pins in the connector to pierce the cables to the wire. But it is an expensive and time consuming process. Also, as stated above, unfortunately the pin spacing on an RJ45 crimper is wrong and even the width of the physical LPF2 connector is wider.  

@Jim I guess if the Root Admin on a site like Eurobricks has been unsuccessful in finding a similar solution then I might be completely out of luck. .

Perhaps, it is just a case of seeing how may turns of a vice it takes to create an LPF2 connector vs shattered plastic.  

Edited January 25, 2022 by James_D

[David Lechner]

At this point in time, I think buying a Powered Up Light (88005) and cutting off the lights is about the same cost as 3rd-party cables and will fit much better.

[C-Brick]

You can get cables for about 2$ each here: https://de.aliexpress.com/item/1005004291123085.html

I have tried "crimping" (frantically pushing the metal parts in with a screwdriver), i have ordered original PV-Productions extension cables (which fit very badly), aliexpress extension cables ironically had better quality and fit. (https://de.aliexpress.com/item/32871195908.html) The new connector PV-Productions uses does intrigue me (pcb based), this seems like a cheap and efficient way of creating a pup connector.