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Comment by h2odragon | Hacker News Reader

Old iron is better built, less "electronic", and far easier to understand the designs and fabricate parts yourself. As well as cheaper to purchase.

Folks I worked with in the 80s were using Michigan dirt moving equipment from the 60s [1], and a quick look shows there's still similar machines being traded [2].

The market for tractors is far bigger than specialized construction equipment, but all the same factors apply. The bigger units, say 75HP and up, counted as "construction equipment" for us, certainly. Today's farms are bigger and today's farmers have little need for smaller machines.

[1] https://www.constructionequipment.com/michigan-elevating-scr...

[2] https://www.machinerytrader.com/listings/for-sale/michigan/s...

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Hmm, early 90s "we" already had about 180hp... Nowadays more like 300 to 400 for a tractor, and more for caterpillar like stuff... With the electronics obviously being a double edged sword... You kinda need them to efficiently use those big machines...

The smaller stuff is still around, but from my experience mostly for "hobby" farmers in Germany :-)

>Old iron is better built, less "electronic", and far easier to understand the designs and fabricate parts yourself. As well as cheaper to purchase.

I thought that big farms take advantage of newer tech on tractors using GPS RTK for sub-inch accuracy and increased productivity? Therefore, depending on the workload, the decades-old "cheaper" tractor can turn out to be more costly because the farm's yield isn't keeping up with competitors. It seems like a tradeoff between old & new.

I believe the argument is that these new tractors are not repairable by yourself, leading to expensive repair and / or replacement cost

>the argument is that these new tractors are not repairable by yourself, leading to expensive repair

Correct, but the tradeoff calculation includes offsetting the expensive repair costs with potential increased productivity. Or likewise with the other option, the "savings" from cheap low-tech tractors may be negated by lower productivity.

That might be justifiable if the service network is basically as fast as a DIY repair, however from what I read it is still treated to be a week-long turnover which might be fine for a low-stake consumer device but a downtime here means that net productivity will be lower than having less efficient but easily repairable machines.

Things will break. Costs isn't everything, time to fix matters. An older tractor can usually be repaired on the same day on-site, causing a few hours of downtime; a newer tractor that will be returned from service in a week causes a huge loss of productivity.

Anyplace you use for service will have a fix it in two hours or you get a loaner policy. The two hours starts when you call, even it the mechanic is an hour away on a different farm. When it is busy season they maintain extra hours

Seems like it would be easily addressed the way car repairs are: insurance pays for a rental while yours is in the shop. So long as peoples equipment isn't all breaking down at the same time, a service with just a few pieces of equipment could probably service a large area. That way you can also get proper repairs done, rather than having to do a quick hack that gets you back up and running by whatever deadline you have but causes long term problems.

Except peoples' equipment would most likely all be breaking down at the same time, because everyone is harvesting at the same time.

At least on construction equipment (agricolture may be different) the point is not only about costs (and frequence) of repairs, but rather on machinery down time or production loss.

I have managed in the past some high production sites (road tunnels) with a specific sequence of operations and having a jumbo or a wheel loader or an excavator down meant severe delays not only in excavation, but on all the following works (concrete pouring, impermeabilization) and on all the "ancillary" works (ventilation, electric cabins moving, etc.).

One of the machine at the excavation front broken for more than a few hours would have meant literally days of delays, complex scheduling modifications, etc., a total mess.

You can retrofit gps control systems onto older machines.

>You can retrofit gps control systems onto older machines.

The highest precision accuracy of RTK devices has vendor-proprietary encrypted signals. E.g: https://www.google.com/search?q=rtk+signal+encrypted+gps+%22...

So it seems like retrofitting for "precision ag" also depends on what commercial "RTK network" is offered in the farmer's local area. I think regular GPS is only ~10 ft accuracy so not sure of farmers are retrofitting tractor steering for that lower resolution.

If you add a serveyed ground station you should be able to do way better than that

>I think regular GPS is only ~10 ft accuracy

This has not been true for quite a while. The equipment used on surveying, farming, and construction equipment is much more accurate thanks to the availability of multiple GNSSs (e.g., GPS, GLONASS, Galileo, BeiDou) and terrestrial base stations to remove error (WAAS, DGPS).

See: https://www.gps.gov/systems/gps/performance/accuracy/

Yeah but you don't need commercial services to get down to the inch anymore. Running your own base station has gotten cheap and easy; witness Sparkfun selling their RTK Express kit like hotcakes.

Integrating it into the vehicle is a fun second ROS project for someone who already built a toy robot car. There's a substantial population of highschoolers building the necessary skills, the trick is just to connect them to the jobs.

New 'dual-band' GPS systems have 30cm / 1ft accuracy without any basestation requirements. The chips cost $250 instead of $10, and they require different antennas, but 1ft is at a point where dropping further IMO has limited gains.

The kit is the GPS and the steering adaptor that reads the signal. GPS isn't encrypted. The protocol is proprietary, but if you can't reverse engineer it in a day you are a poor engineer. (I wrote the decode for one sub inch GPS, I don't know about our competitors, but I don't see why they would encrypt GPS)

What is encrypted is the steering algorithm to steering controllers. That is about safety, tractors have technically been level 4 self driving for 30 years - not even marketing says that though because the sprit of level 4 self driving is about safety and tractors are just as unready for self driving as any other car on safety grounds. By encrypting the steering control lawyers can ensure the safety warning is displayed. (Sometimes a university is given the encryption keys after legally verifying they won't be unsafe)

Looking again, you seem to be about Rtk. I'm not sure about that. Probably encrypted, but mostly for those who want to charge, you can buy your own base station.

well that sounds like marketing, which sometimes marketing can be correct, and sometimes it can be a bunch of BS. I don't know which is the case here but my hunch would be that if it were correct then old iron wouldn't be worth more than new to the people who would be best suited to know if it were BS or not.

There at any rate seems to be a discrepancy between what is supposed to be the case, and what people who should know seem to believe is the case.

>sometimes marketing can be correct, and sometimes it can be a bunch of BS. I don't know which is the case here but my hunch would be that if it were correct then old iron wouldn't be worth more than new to the people who would be best suited to know if it were BS or not.

I don't know if the auctions bidding wars are driven up by homeowners managing their small homestead farm or by bigger commercial operations. Homeowners don't need to compete so buying 30-year old tractors is an easier decision.

I agree that using old tech can be an counterintuitive cost-saving strategy -- like FedEx deliberately using a fleet of very old planes that are gas guzzlers instead of buying the latest jets that are more fuel-efficient. Maybe some big commercial farms deliberately buy used low-tech tractors. When I drive around, all the big operations seem to use the newest tractors. They seem to always trade up instead of down. But maybe the latest John Deere "lock in" and repair costs will make them reverse that buying pattern.

The big farmers are putting the equivalent of 75000 miles per year on their tractor. They are wearing their tractors out and can't afford for it to break.

From the heavy equipment operators I watch, a lot of them have an extreme dislike for DEF and the regen cycles that all modern diesels over 25hp (iirc) require.

Yes "emissions" engines have a reputation for unreliability and costly maintenance.

In my (post-Soviet) country it's still quite common to see Kamaz construction equipment (actual construction, e.g. light-weight cranes) from the 80s and 90s being used.

It's not that new equipment is not affordable (if something needs a 100t Liebherr crane, it'll come), but all the emissions equipment on new vehicles is a lot more expensive to maintain, so it's simpler and cheaper to keep old vehicles running.

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