Wiring Question and help

[GEOEng03]

Hi,

Made a bit of a fumble when I tried to re-solder wires to a pcb board.  This was done badly (I admit that my soldering skills are mediocre, but enough), given the tiny size of contact points on the pcb. The contacts have barely any give when you remove the body and it quickly stopped the loco from working when two of the cables came undone.  The picture below, is the aftermath of my botched attempt!

 

IMG_20180123_073437002 by Bryn Jones, on Flickr

 

Anyway to cut a long story short, I have ordered a replacement pcb board, given up trying to fix the other one - too tiny and I don't have the most patience for tiny things like this. But the issue I have is that the plastic on the power feed cables from the non-motored bogie melted together.  I have managed to split these and the majority of the sheath is still present, but some has melted away. Now, the wires are still connected to the lower board (fortunately), and I hope that I can just sheath or protect with electricians tape.

 

IMG_20180123_073413874 by Bryn Jones, on Flickr

 

This one shows it better.

 

IMG_20180123_073348419 by Bryn Jones, on Flickr

 

I just wonder, whether there is a better way of insulating that RMwebbers know about.  Advice greatly received.

Cheers

[DCB]

I simply use insulating tape.  First I lay a decent length along a clean sheet of glass and then cut it into narrow strips with a Stanley knife with a brand new sharp blade using a metal ruler or my special Brass angle edged plastic ruler as a guide. The tape can be removed from clean glass with no damage (except you scratch the glass)  The thin strips can then be wrapped tightly and neatly around the wires,  tweezers come in handy.   I started doing this on repairs to car wiring looms as most rolls of tape are far too wide for a neat job even the 6 for £1 deals in Poundland.

[cliff park]

Heat shrink sleeving. Maplin sell it in lots of different sizes, work out very carefully what size is right for your needs. Use heat from a soldering iron to shrink it, it doesn't matter if the iron touches it, I usually use the part of the iron back from the tip and rub it along the heatshrink. If you get the right size (it's cheap enough, buy a range around what you think is right) it will be hardly any bigger than the original wire. 

Edited January 23, 2018 by cliff park

[GEOEng03]

Thanks Gents, looks like it is either heat shrink or tape. Will probably go for a combination of the two.  The PCB has turned up, so that will be a task for later. Bloody Hornby, virtually no give in the wire that connects between pcb and chassis...

Cheers

[kevinlms]

Thanks Gents, looks like it is either heat shrink or tape. Will probably go for a combination of the two.  The PCB has turned up, so that will be a task for later. Bloody Hornby, virtually no give in the wire that connects between pcb and chassis...

Cheers

Wire costs money, so every millimetre counts!

[SHMD]

Thanks Gents, looks like it is either heat shrink or tape. Will probably go for a combination of the two.  The PCB has turned up, so that will be a task for later. Bloody Hornby, virtually no give in the wire that connects between pcb and chassis...

Cheers

 

Multi-strand wire soldered to PCBs are often soldered poorly with the wet solder being allowed to wick up the wire. This makes the wire very stiff and where it ends the copper strands then become the bendy-bit which work hardens quickly and snaps off.

 

Using the smallest heat shrink that can easily slide up the wire, (before soldering), AND back down over the now cooled soldered joint is the best way as this heat shrink also acts as a strain-relief for the wire at the crucial joint to the PCB.

 

 

Kev.

[GEOEng03]

Thanks again all. I have successfully sorted the issue and all is working well. Thank goodness for spare parts, though it took me the best part of 3hours to sort (had to remove windows to get the PCB out!)  Good old Hornby....