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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.
I would love to see some photos to cement these ideas. I have plans to mess around with lawn tractors myself.
I would be happy to share but the tractor is currently buried under a bunch of snow. If you remind me in the spring I will share!
What, you didn't build a snow blade for it :-)
I was just happy I could start mowing again. But since it is a Craftsman they have a ton of accessories available on the used market for very cheap so I might pick up a plow for like $100 to see how it does for next winter.
Very cool, I love electric conversions. I will confess though, that removing the belt drive makes me nervous - they're often important to protect either the machine, or people, when the blade meets an obstacle.
The Ryobi walk behind mowers are direct drive and everything is underneath the deck so there isn’t much that can go wrong that you wouldn’t contend with if you were standing with your toes next to it except you are actually riding it. The wheels still do have a short belt and a tensioner but not the really long belt with the clutch pulley. The only safety thing I could have added is the electronic brake on the deck motors but for my use I am not super concerned about letting things slow down unassisted. As soon as I leave the seat everything shuts off and the light blades don’t actually have a ton of momentum without power.
Gotcha - thanks for taking the time to help allay my fears.
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.
He mentioned hills - I would be worried about kids rolling it and getting crushed. I've got an old sit-on mower and it is very heavy.
I'm in New Zealand and we have a number of deaths every year from quad-bikes on farms. Often children. They are being careful but quads on slopes are dangerous.
You can buy those transaxels (different number of speeds) surplus fairly cheap, but you have to look.
Though the goal was a kids toy, and those mowers are too large for that use.
This is one I know of off the top of my head: https://surpluscenter.com/power-transmission/transaxles-tran...
Way cheaper to find a broken mower.
They're constantly sold dirt cheap in my area with very minor problems, like old gas. People don't know how to fix it, so they buy a new one and sell the old.
I bought four working mowers. $500, $250, $220, and $200. One was missing a deck, one was running rough. Otherwise complete.
They're all craftsman, one vintage from the 80s.
We use one to mow, one to move the trailer, the old one mows but it mostly sits, and the last was a gift for my wonderful neighbors who are old and were still using a walk behind.
That's how I buy snow blowers where the fix is usually clean the carb jet or replace it for 20 bucks.
Kids grow. If it were me I'd just remove the mower deck, throw an extra muffler in its place (because without the deck the engine will be the next loudest thing and I don't wanna listen to it). Maybe lock out the top speeds depending upon age/yard topology.
Stuff goes straight to permanent memory at that age so by giving them a "real" tractor there's a lot of potential to learn good lifelong lessons prompt them to ask the kind of questions that result in good teaching.
But those are internal combustion engines, so each time your kid want to have fun, it annoys everyone.
I'd rather have my kid ingrained with the idea that electricity is the future even if it's an amazing achievement to be able to tame explosions to move around
Right, that's why I mentioned nabbing one without a working gas engine and converting it to electric as the focal point of the project.
Ha sorry, thanks for the explanation
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."
This is new? Farmers have been using Belarus tractors for decades. As far back as 1998, I remember a friend in SK whose father had one on his wheat farm.
I am not a farmer, dude. But if I were to buy a car in central Europe, it would probably be a pre-AdBlue diesel.
What's your beef with AdBlue?
To me it seems just like another layer of complexity.
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
Yes I'm using flux-core wire and I do indeed have the polarity set for flux-core.
My conception was that we're adding power by increasing the voltage and we're stacking up material by adding wire, so to get good penetration on thick material I want lots of voltage and not much wire feed.
But actually it turns out that you make it hotter by increasing the wire feed speed.
I don't really see why, but at least now I know.
Here's a more recent weld: https://img.incoherency.co.uk/6464 - still not great but not nearly as bad.
Nice weld, and nice project!
I'm learning with you.. the polarity was fresh in my mind because I recently got half way through a project with little bb's splattering everywhere before a friend with more knowledge asked if I had recently changed wire.
Welding seems to be a lot like baking; It is very deterministic in a sealed environment and the parameters are well understood, but in practice the experts rely heavily on feel and experience more akin to an artist.
I haven't seen welds that bad since visiting India, where I ran across some so dire I was compelled to photograph them in case the building fell down later: https://imgur.com/a/16FRlEW
Love the spirit of the build, though, and it's a case where weld cleanliness doesn't really matter, so, more power to him.
the last section discusses this. the author was having problems relating the feed and the current settings to the weld characteristics. personally I prefer to manage all that with a pedal and manual feed with a tig
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!
Came here to post the same thing. Very entertaining series of videos!
Completely unrelated but https://protohackers.com/ is another one of James’s projects that I love. :)
He also built a homemade computer from scratch. James is a brilliant guy.
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
I came here to say the exact same thing. This is so refreshing.
I thoroughly enjoyed it. No BS, no ads, no sale pitch, no AI, no pretending, nothing. Just a stranger sharing with the world a project he built at home.
Those picture of the welds are inspiring. It is as honest as it gets. Loved it.
Thank you.
It's a thing made with no attempt to become rich and famous.
What the heck is it doing on HN's front page?
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.
I've used a length of old vinyl hose, split open lengthwise, to cover sharp corners/edges on some of my projects. Really saves tarps from tearing along sharp edges.
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 ?
I think it goes about 6mph. I agree with your maths though, so probably my estimate of the gear ratio is wrong.
I don't know how long the battery lasts, we have never driven it for long enough to flatten the battery.
While I was building it I used it for about an hour doing several laps of dragging a "trailer" full of rubble from the top of the garden to the bottom (the easy direction - empty load on the way back up) and it became noticeably slower towards the end but still got me up the hill. So I'd say it lasts over an hour.
Thanks for info. And once again really nice project :)
Relevant -- Snowblower electric conversion
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.
> 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.
Driving even basic PTO attachments? That’s borderline
oh so there are levels to cardboard-assisted design
truly awful craftsmanship, I love it!
Hacker News is turning into Hackaday. Sad.
Projects like these make me want to buy a laser welder. They are awesome and perfect for hobbyists who want to level up.
I use a MIG welder but with flux-core wire and no gas, I got it about 12 years ago for £200 (new), it is a perfectly good machine and I am not a good enough welder to get the most out of it.
It's much cheaper than the laser stuff. It gets expensive if you want to use gas, but if you stick to flux-core you don't have to.
You might want to look up the max thickness and other common issues hobbyist level laser welders have before purchasing, or at a minimum wait for the laser welders to mature a bit more. You'll spend less than half and be far better served with a cheap tig welder at this point in time.
I’m mostly concerned about the learning curve. The laser welders I saw can be used blindfolded and offer enough penetration. I noticed a lot of negative comments but mostly from people who spent years honing their craft and feel obligated to gatekeep it a bit.
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Video please.
Videos take a lot more effort to make. Probably better that the guy focused the wor on the tractor than on filming...
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.
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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.
Dude reinvented Power Wheels from first principles and you're over there claiming a death trap? Questionable premise is questionable. Anyway keeping kids perfectly safe is how you raise high anxiety incompetents. Learning to assess and manage simple risks is a fundamental part of childhood development.
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.
This is a thing for a child. The aim of such projects is to get it built before they grow out of it. I think given the duration and duty cycle of usage it will be fine.
The discourse on here would be much better if commenters at least glanced at the article.
Thanks, I'll let you know how it holds up after our first round of ploughing.
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.
Crafted by Rajat
Source Code