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Oof, those welds are ugly. The author comments on the welding at the end of the article, but I'd venture a guess that if using a MIG setup the polarity may also be reversed and/or gas shielding may be wrong. On my machine the flux core wire vs solid core wire with shielding gas require opposite polarities...

source: I'm a terrible amateur welder

I did something similar last summer. My Craftsman LT1400 uses the standard 500cc Briggs motor and that motor has some tragic design flaws that make it grenade itself roughly once a season. I went through a couple of these motors rebuilding them (correctly) until I gave up.

I ripped the tractor down the the frame and removed most parts. Got $40 Ryobi walk behind mower motors (42V which is really 36V), some scooter controllers, and pulleys. I used two scooter Li ion batteries but I should have just gotten three large lead acid 12V batteries for more capacity. Still, I can mow for an hour or so and get almost an acre done which includes some hills per charge. It took about 8 total days to build and about $800.

The way I set it up is that I have one motor drive the wheels and two more motors on the deck directly driving the blades. The belt system the ICE motor version had was insanely inefficient. This system has like 20% of the power but mowed better and is way more reliable. For $150 I could get a solar array and controller to charge the batteries and never pay for anything but belt and blade replacements for life.

The hardest part of the build was lining up the mounting of the drive motor and wiring up all the safety systems (brake sensor, seat sensor, etc). The kicker is that this is a way better product than what I can buy commercially unless I get into the $5k+ territory and is completely user serviceable. No part here is more than $100 and they all readily available. The tractor has enough torque to push my huge picnic table around while I am riding it. I might try seeing if I can plow snow with it next winter.

Were it me, I would have started with a pre-2000's Craftsman mower as a base. They have a 6 speed transaxle with a differential (which solves the steering problem mentioned) and a built-in brake, and examples with broken or missing gas engines can be had used for $100 or less quite often. They have that boxy sheet metal look of old tractors too. It would also be possible to adjust the pulley ratios to slow it down or just block off the higher speeds until the kids get a bit older.

Granted, I understand that the purpose of a project like this isn't just in the end result. Depends what crafts you want to practice and what's just necessary work around them. There's still quite a bit of fun project left in converting an existing mower to electric and refinishing it to look more like a classic tractor.

I want one :-(

Other interesting Story about tractors:

"In the heartland of American agriculture, a quiet revolution is underway. Farmers, long frustrated by the high costs and restrictive repair policies of leading tractor manufacturers like John Deere, are increasingly turning to simpler, more affordable alternatives from an unlikely source: Belarus. These rugged, no-frills machines from Minsk Tractor Works (MTZ) are gaining traction not just for their price tag, but for their deliberate avoidance of the complex electronics and subscription models that have become the bane of modern farming."

Really nice project - respect :)

Got two questions: 1. How fast it can ride ? If I good estimate (based on max 2750 RPMs for electric motor MY1016 350W 36V, gear ratio ~100:1 and height of rear wheel ~0.5m) it should got about 0.8 m/sec. So really safe for kids and dad :)

2. How long does the battery last ?

> You may be thinking that 350 watts doesn't sound very powerful

You might be amazed at how little power you can get away with in an actual tractor. 20HP is close to the upper limit of practicality unless you are running a large commercial operation.

LiamTronix on Youtube has some videos (ex: https://www.youtube.com/watch?v=7iEUp5Z1aNw) on converting a popular farm tractor (Massey Ferguson 65) to fulling electric.

Fun stuff!

I love this! I appreciate regen breaking will be hard to add without picking a new controller and so on but perhaps you could add a DPDT switch wired into the break that adds in a string of 3 old incandescent 12v break lights.

I’m love content like this. It reminds me of the mid-2000s era of the internet.

Is this “best” project I’ve seen? In terms of tech,quality,etc No. Neither are mine. This guy built a really fun project for his kids.

I love this. As AI slop gets increased, I hope that content like this starts to get filtered up to the world.

I also learned about a web-ring from his website. I think this is an artifact from the early Internet. I hope this gets more popular for website discovery reasons

https://webring.stavros.io/

Hacker News is turning into Hackaday. Sad.

If it's for kids, I'd round off those corners or add some kind of semi-flexible skirt around the bottom, because that outward 90° jut on the foot shelf by the front wheel looks potentially... painful.

Relevant -- Snowblower electric conversion

https://youtu.be/D8OJFHLiRxM?si=lUZwjFEMoxqveDb5

Completely unrelated but https://protohackers.com/ is another one of James’s projects that I love. :)

Projects like these make me want to buy a laser welder. They are awesome and perfect for hobbyists who want to level up.

Video please.

It's a tidy build, and I guess it's a fun kid's toy. Wood is a baffling choice of material for a (lawn) tractor chassis by someone who clearly owns a welder. Don't start lecturing me about Morgans and ash-- that's a whole different thing, and there's a reason they're basically the only serious company still shipping a wooden vehicle chassis.

I'm a farmer, I know what working vehicles are subjected to over time, and I know that when plywood gets wet, it swells, warps differentially, splits at its layer boundaries, and starts to twist. Tractors are for driving over land that is often at least damp. This is not a recipe for durability.

oh so there are levels to cardboard-assisted design

Sorry to be boring and safety focused but no child should come with 20 feet of that it’s a death trap.

Literally children die from riding on such things.

Keep your children safe a well and alive, dont let them on anything like this or near one being driven by someone else.

Without an anti-roll device this could be quite dangerous, even for a toy sized machine. A roll bar is a simple and effective precaution.

truly awful craftsmanship, I love it!

Garden should be a place where people can touch grass, leaves, flowers, fruits, plants, soil, rocks and maybe trees, without going out to a park. Ensure that children do not miss out on that. I'm not a big fan of anything that makes children to avoid their exposure to walking (prams etc), touch with ground or outside environment.