With the mechanical’s of the drive train virtually complete the wiring had to be worked on next. The first issue to deal with is the main power relay, initially I’d bought a 150A unit from the local Altronics, this one:
This is relay has spade connectors, however they do not sell any form of connectors that would enable a large enough cable to be connected to it to carry the required current. So effectively it was useless.
I replaced this with a Hella 3061 relay that’s rated at 100A continuous and 180A peak. Being Hella that’s believable too.
This one has 6mm bolt down terminals, so is straight forward to connect to. The unit is too big to fit in the fuse box with the other relays and although an automotive unit Hella don’t quote an IP rating for it. So considering where it needed to go, I printed off an enclosure for it to sit next to the fuse box (Glow in the dark ABS of all material). This is the white-ish thing in the picture below. There’s a screw down lid for it that should seal it fairly well.
Below is what’s going on in the fuse box, its not yet finished, so not tidied up properly yet. The pink bit is a 3D printed ABS part, underneath that are 3 power switching relays. This box has everything in it that relates to running the engine. There’ll be a separate box for the lights, horn, etc.
With enough of the wiring done, I could test that turning the ignition key powered things up, then after checking for blown fuses and escaping smoke, satisfied that it was OK at that stage, the starter was tested and that worked also. At this point I was running out of excuses to not try and start the engine which I think need to do before I tidy up and finalize the wiring.
Another critical path job is to get on and get these parts for the firewall made and installed so I can then assemble the cooling system…
These are the first ‘proper’ FRP parts I’ve attempted, the photos were taken after I cleaned the utter devastation that was the bench after the job, this is the start of a big learning curve.
The one on the right looks funny as that’s baking foil on the inside I, on that one I pressed the prototype part back into the mold to hold the cloth up against the mold that worked pretty well but there were other issues with it, anyway learnt some things along the way. I though I had 2 usable parts made but the flanges on the baking foil part are just not right, so I’ll remake that one in the same way I made the other using several pieces of cloth per layer of glass.
The molds were printed in ABS which I’m finding easier to get a nice finish on than PLA at the moment, as per the advice from Fibreglass & Resin Sales PTY LTD (fibreglass-resin-sales.com.au) I put 5 coats of wax in then 1 of PVA release agent, I had no issue getting the part out.
I am really happy with the surface finish (still need to wash the PVA off), I did no sanding on the molds (I really hate sanding), and only scraped off the pimples and ridges, on the parts where I didn’t screw the layup up the finish is more than good enough that I think it could be more or less hit straight with high build primer. In this case both sides of these parts will be covered (heat barrier and cloth). So no problem regardless.
Next up will be bigger parts with more thought and better prep before I start mixing resin.