Specific problem: on my model railroad, I have a PCB with 8 wires hanging off it. I need to split them out into a 2 pin + 2x3 pin connector. I don’t want to permanently solder them to the carrier wires since at times I need to be able to remove the PCB from the layout.
carrier wires vary up to 20 AWG. Current is low, but it’s an outdoor layout and easier to run more chunky wires around.
Requirements:
either multiple 2-3 pin headers or a single multi-pin header that I can attach smaller connectors to.
fixed orientation connectors are helpful but not mandatory
Happy to either crimp or solder. If recommending a crimp solution, please also recommend a crimping tool.
Do you have any advice as to whether the connector attached to the PCB should be male or female? Whatever I decide here, I want to be consistent throughout the layout.
Can you mount the PCB on a base of some sort? Then mount a piece of PCB strip board onto the same base, solder some screw connectors to the strip board and solder the PCB wires to the strip. That would avoid having those fine wires just hanging off the PCB.
For example:
Hi Andrew
Google “solder sleeves”. These devices very rarely get a mention on this type of forum but are extensively used in the industry. You may have a use for them here.
They are essentially a bit of heat shrink (clear) tubing with a ring of eutectic (low melting point) solder inside. The application of a heating tool shrinks the tubing and melts the solder making a good water tight connection.
Cheers Bob
Hi Gerard
Yes they do work well. Also Kosher for military applications. I also have a gas powered soldering tool with a hot air nozzle which has an accessory to “wrap” the hot air around devices like these solder sleeves. Raychem also have a dedicated hot air tool especially for these sleeves.
Cheers Bob
OMG! Bob, I had no idea these were a thing. They look ideal for a bunch of things, much easier than my current workflow: solder, realise I forgot to put the heat shink on (almost every damn time), desolder, put on heatshrink, resolder, heat shink
Hi Doug
These have been around for over 25 years to my knowledge.
Cheers Bob
Just looked it up. Patented by Raychem 1966
EDIT. Like always there is a down side to these things. Cost. Raychem is really the top of the line re quality but some of them can be very expensive. There seem to be lots of others of unknown quality (unknown to me anyway) out there that seem to be very reasonably priced, especially with the larger packs of assorted sizes. My involvement with these devices mainly was in a military environment where EVERYTHING had to be traceable and accountable so Raychem seemed to be the universal brand of choice. This had the advantage of being an approved product and as such was not subject to the rigorous scrutiny and testing required to get an approval of an alternative product. We even had to use the approved Raychem heating tool in their application.
Having said that, they can be very useful and I feel that for hobby or home constructor use the more economical types would be fine. Only use would prove or disprove that.
It won’t give you the same firm connection as soldering or a connector with locking lugs but they’re a bit harder to find when you’re mixing wire gauges. If you’re after something that’s going to lock more firmly you could try searching RS Components or Element 14 for a suitable Molex connector but I couldn’t recommend a particular series of connector myself.
Hi Andrew
If your solution involves micro crimp terminals I highly recommend getting a quality crimping tool. These things are so small and fiddly - you will need a precision tool.
A bit pricey but I use the Japanese “Engineer” brand in a multi die version like this:
If you end up with screw terminals I recommend using bootlace ferrules with a 6 jaw tool like this:
