Model Railway Forum

I'm starting to think about wiring up my first proper layout. Basic DC. I was looking at PVC coated wire and keep coming across silicone coated (eg. this one https://www.amazon.co.uk/TUOFENG-Electr ... _item?th=1 )

It seems to be a similar spec, more flexible and cheaper. What downsides am I missing, there are bound to be some

Hi
The link takes me directly to 30 AWG flexible wire which IMO is far too small. Look for the 24 AWG as a minimum for general DC layout wiring, 24AWG is approx equal to 7/0.2mm equipment wire). For solenoid point motor feeds use at least 20AWG size which is roughly 16/0.2mm

Silicone insulation is often used on heatproof soldering iron iron leads. In my experience excluding heat damage they do not last as long as PVC with the outer insulation developing cracks where subjected to repeated bending. You can get very flexible PVC cables with the flexibility coming from using much finer stranded wire in the core and I should imagine by varying the plasticisers in the PVC but not sure on that last point.

Richard

Yes I haven't got my head round the correct sizes for the various uses yet - that's on my list before I buy. Thanks for the starter for 10 Brian. But size-for-size, silicone will be similar but possibly not last as long from Tricky Dicky's experience?

You can obtain lengths/rolls of suitable PVC coated wire from ebay or other electrical suppliers quite cheaply. Often in 10Mtr or other lengths and insulation colours. If you want 100Mtr reels then CPC Farnell or Rapid in the UK are among the cheapest.

As a rule of thumb for general use...
7/0.2mm equipment wire for DC rail feeds and general layout building lighting, colour light signal feeds etc. Plus Stall type point motors.
16/0.2mm for solenoid point motor feeds and DCC rail droppers.
32/0.2mm for DCC Bus pair of wires.
These are the Minimum sizes I recommend.
The main thing to remember is that using a larger wire wire size will not cause any issues normally, but if the wire is too small in conductor size it may well lead to issues especially around volt drop and current flow.

I can't see any need for the use of silicon coated wire on a layout?

I wouldn't use it for wiring the layout and would be surpised if like for like cable size and spec it was cheaper

As has been said it is prefect for a soldering iron so if you haven't got one yet consider it.
1: its more flexible so you dont have the flex tugging at the back of the iron as you try to get it in somewhere pokey
2: it doesn't melt so if you touch it with the tip you dont have any excitement
3: it coils up neatly so is easier to put away

Chris I'm confused.... you said you wouldn't use it but then say it's perfect for a soldering iron for 3 reasons?

I read it as ......

Not good for layout wiring.

Is good on a soldering iron.

R-

slbhill wrote: ↑Fri Jan 10, 2020 11:07 pm Chris I'm confused.... you said you wouldn't use it but then say it's perfect for a soldering iron for 3 reasons?

The reference to Soldering Iron is correct. A three core mains silicon cable when fitted to a soldering iron is the bees knees as its highly flexible, unlike the three core PVC mains cable. It doesn't burn if the hot tip touches the cable and as stated it coils up easier than a PVC 3 core cable does.

But its use on the layout is IMO OTT and stranded equipment wire of the correct wire size will usually be far cheaper and more readily available.

RogerB wrote: ↑Sat Jan 11, 2020 6:18 am I read it as ......

Not good for layout wiring.

Is good on a soldering iron.

R-

yes that's what I meant