Forgot to mention I also have fully functioning brakes, an important bit. It is much faster than the chain drive but can still run it full bore at maybe 10 m.p.h. Enough for a mower, I suppose. Also this didn’t seem to put any strain on the motor, which stayed cool. Also noticed my older battery is going bad and neither is fully charged. So maybe it would be a little bit faster. I’m starting to lust after those pricey lithium batteries. Much quieter than the old mower but the transaxle probably needs some grease, after 20 years of mowing in the Texas summer.

I was been simultaneously itching to try out the new direct drive on the riding mower project, but also a bit afraid. It something burned up or broke, I was probably finished. So I promised myself I would do it right and reassemble the whole back end and put in a proper kill switch. And I was distracted with the blades.

I decided at the last minute to keep the big blade height handle. I figured out a way to connect it with the new motor set up. Hopefully I will be able to use it to control the blade height. At this point I am happy with the motor and the electronics. I will post a video in the next posting.

I feel like I’m getting to the end of this one, at least the 1.0 release. There are a few pieces left.

Shifter: the shifter is large and probably over designed. All it does is push a small rod into the transaxle to change from forward to neutral to reverse. With an electric motor, this isn’t really required. The motor is easily turned off and even reversed. All that said, it isn’t in the way and it could be useful, for instance, to put the transaxle into neutral. Tempting to take the mechanism down to simplify things but it will stay, for now.

Brakes: there is a brake lever on the transaxle very near the shifter. In the photo it is connected to the spring. This is connected to a rod and to the large pedal. This pedal was a combination brake and clutch and had some complex mechanical and electrical interlocks to the old blades and engine. The pedal works well enough but needs some springs to keep it in place. Looking at repurposing some of the old springs. Will also have to put in a stop using a bolt. My other concern is braking with the motor engaged. It is possible to mount an electrical switch to turn off the motor when the brake is engaged. We will see if that is necessary in practice.

Blade Height: the metal bits are the original blade deck lift mechanism. I intended to use it, even though it was overkill, but the mounting of the motor made me take it down, piece by piece. I may yet use some or all of these pieces and mount points to control the mower blade height, but this is still open. Perhaps the last open design issue.

The blades are just some 24V scooter motors with heavy duty weed whacker blades mounted on them, all mounted into some 2″ PVC pipe. Wired it up using my fancy new WAGO lever nuts and hooked it up to the new controller. Need to put in a safety cover and figure out the mounting and lift mechanism but it looks up to the job. Still haven’t ridden the direct drive yet. Going in a few different directions at once.

Installed the replacement controller for the blades. Still no idea what happened to the old one. The new one doesn’t have an LED display, which I really don’t need. I was tempted to leave the switch out, too, since the speed knob also is an on / off switch, but decided to leave it in. Easier to reverse the blades, which are sharpened on both sides. Had to cut some new plastic for the dash, but I am getting good at that. I also realized that my kill switch is “normally open”, the opposite of what I need, so I ordered a new one.

On test I heard a pop and smelled something burning. Damn. I had wired the new controller battery outputs to the motor terminals. It was labelled in only Chinese, but it matched the old one and I could read the English on the circuit board underneath. Totally my fault. Seems I blew a 30A fuse on the battery cable that I put in just for extra safety. I am becoming a big believer in safety.

Swapping the fuse, the motor controller still works, but haven’t hooked up the blades to see if I damaged anything. Also been studying the brake and the blade deck lift mechanism. Both are big and heavy and complicated. Going electric simplifies just about everything but now I need to re-invent the lift and the brakes. Oh, used some of these German wire connectors. No reason to go back to wire nuts. I’m told to be careful and buy the real German product and not cheap knock-offs.