Shore power for the Polo
Now that I don't drive anywhere really (I've put one tank of fuel in it this year) I have an issue with the battery going flat. In the summer months I've been using a little solar trickle charger which mostly works if there are enough sunny days, but it barely does anything in the winter so I had to get a jump pack. The jump pack mostly works as well, but on the colder days even it can struggle to start the car due to it being an old mechanical diesel. I assume the battery is sapping the boost power, as opposed to it going straight to the starter. Once the car is running it will then start fine without help for the return journey, even after a short trip to the supermarket so I just need to keep the battery topped up to allow that. Running the battery charger/maintainer to the car is a bit of a hassle to do it regularly, as I have to then put the extension reel in the car, and then deal with connecting it up under the bonnet, or disconnecting it/putting it away when going anywhere. Especially in the winter when it's cold, dark, and rainy.
Enter MagCode® which I learnt about from someone on the LandRover discord server who was using them for powering a lightbar, and after looking into the connectors a bit more I saw they are actually designed for hassle free trickle charging of vehicles. They are magnetic connectors so if you forget to disconnect it, it will harmlessly pull away from the car as you drive away. They are quite expensive though with the plug, socket, and cap coming to a smidge under £60 but I feel that's worth it for the ease of use it will provide.
Next up was working out where to install the socket on the car, I didn't particularly want to drill a hole in the wing, or the bumper. Mainly as the connector would stick out and might get caught on something or bumped. The polo has removable "fog light" (it doesn't have front fogs) trim pieces in the grill to allow access to the bumper fittings, so I decided to mount it on the nearside one, the one the same side as the battery. Annoyingly it has fins on it so like all good car projects, a piece had to be sacrificed for the greater good. The cut is a bit messy as I couldn't find my dremel, so had to use a combination of tin snips and the angle grinder with a 1mm disc.
Then I had to design a blanking panel for the grill piece and to mount the connector on. I took some basic measurements and mocked up a shape in Tinkercad, this was then 3d printed very thin in PLA so I could use it for refining the shape and hole locations against the grill.
This was drawn on with sharpie and then measurements taken and modifications made to the cad model. After several prototype prints to check the refinements I had the final design.
This was printed in PETG filament so it's suitable for outdoor use, the panel is 3mm thick. I also printed a little tag for it which was crudely superglued in place.
I offered it up to the grill part and drilled out the 6mm mounting holes. Then it was bolted into place.
Then it was just a case of fitting it onto the car. My trickle charger came with a loom that has ring terminals one end for connecting to the battery and a SAE connector at the other end. Luckily this was long enough that I was able to feed it down behind the bumper to where the trim clips in. To connect the SAE connectors together you annoyingly seem to need a middle piece else the polarity swaps over.
With the trim clipped back in place and the plug connected to the socket
Showing how easily the connector comes away
The lead goes to a secured point, so if I reverse away without disconnecting it'll just pull away like in the clip. The battery maintainer lives in a weatherproof box by the car currently and it isn't automatic so I still need to press a button to get it to charge/maintain, but connecting the car up and doing that is a lot easier than dealing with a normal extension reel and having to open the bonnet.
Parts List:
Magcode Plug/Socket/Cap: £58
SAE Leads: £9
SAE Adapters: £7
Weatherproof box: £10
Battery Maintainer: £30