Tractors are one of the most important agricultural pieces of equipment, but can also be one of the most dangerous. Annually, 300 to 400 Americans are killed in agricultural accidents involving tractors, and 50% of these involve roll overs. Every year farm workers are injured by not following basic tractor safety rules. OHSA states that tractors should have standard seat belts, a standard roll-over protection, protection from tractor fluid spillage, and sharp surfaces protected.

Rails and steps need to be in safe condition to prevent falls from the tractor. When operating the tractor, take safety precautions for your personal well being by pulling your hair back; do not wear clothing or jewelry that is long or dangling. Wear work boots, gloves, also hearing and eye protection. Children and passengers are not to ride on the tractor. Children are injured every year from falling moving tractors.

You need to understand the capabilities, power, safety features and general operating procedures of your tractor. Make sure that your tractor is well maintained, so that you are not trying to repair it in the field. Make sure lights and warning signs are properly functioning, especially if driving on the road. Never refuel your tractor when it is running or overheated. Do not refuel near the gasoline pump, and always carry a fire extinguisher. Ventilate your tractor so that carbon monoxide gas does not effect the driver, especially in a closed cab. Always turn off the engine, when getting off your tractor, putting it in gear and with the safety brakes on. Have children and workers stay clear of the wheels to insure slipping from under them Workers need to take caution when around the machinery in case of flying debris.

Operating a tractor is different than a driving a truck or car. Driving with your wheels spread evenly and far out; will stabilize the weight of your tractor. Popping your clutch can tip your tractor; make sure you understand the gears and how to use them properly. Uneven terrain, ditches, and deep crevices can cause a tractor to rollover. Inclines especially steep inclines can change the center of gravity on your tractor and make it tip easily. Reduce your speed when turning and using a front end loader, both of these can unbalance your tractor. Use the hitch as it was intended and read the manual for weight limits and loads to prevent changing the center of gravity for your tractor. Agricultural workers can be killed or injured when trying to hitch machinery with improper backing of the tractor. Never stand between the machinery and tractor.

When driving your tractor between fields on the roads, be sure that all signals are properly working. Follow all the rules of road, and tractors may not be used on the highways. Be aware of drivers that are impatient with the size and slowness of your vehicle; they may drive erratically to pass the tractor. Never use a tractor for transportation to and from town. Use your tractor for the work it was intended to do, to insure your safety.

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Back when folks initially began putting together their own electrical cars they didn't have many cost-effective choices in motors. Regularly the first EVs used surplus aircraft starter-generators as a motor.

the times of plodding electrical vehicles were numbered.
rating in an EV. 'Electric cars are driven by large electrical motors typically rated between 3.5 and twenty-eight h.p.. For those used to gas engines, this may not appear like much power, but the rating systems used for gas engines and electrical motors are so different the numbering system is sort of incomprehensible. Gas engines are rated at their peak hp, electric motors are rated at their continuous hp. The motor installed in Eve is a complicated DC FB1-4001. This is a 9' diameter, 140lb series wound DC motor. I bought is back in 1995 for our first EV and, as long as we don't abuse it, the motor should last for decades. The one part that wears out, commutator brushes, typically last eighty thousand miles and are pretty straightforward to replace.
On the first EV I failed to tighten one of the motor-transmission adaptor set screws and over a period of five years the adaptor worked its way back into the motor faceplate and wore away some of the metal. In the process it damaged the bearing. I found a local electric motor shop to replace it for $100, including parts and work.
You will find more details on our Mazda 626 motor and adaptor page. Most EVs use series wound motors, but you may pick up permanent magnet and AC motors, even experimental wheel center motors.

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In a nutshell here are the 6 main things to remember when TIG welding 4130 chromoly tubing:

1. Preheat is not necessary for tubing under .120" thick. however it sure won’t hurt anything. If the ambient temperature is less than 60 F, I would say preheat to at least 100F. You can easily do this with a small propane torch from Home Depot.

2. Weld a little slower than normal. This just makes sense. Think about it. If there is an ongoing argument about GAS welding being superior than TIG welding for Chromoly tubing, then it makes sense to go just a little slower when TIG welding. This will slow the cooling rate and negate any chance of the welded area cooling too fast.

3. Don’t allow any Breeze or drafts in the room and do not speed cool the welds.

4. Use a TIG machine with high frequency starting to eliminate arc strikes. I had a "German Eye" pocket knife once that someone had used to cut a live wire. The small arc on the blade stuck out like a diamond and would not wear down with a file or sharpening stone. The same thing happens but to a lesser extent when you get an arc strike on 4130 chromoly. You get a hard brittle spot and a crack will definitely start there.

5. Do not use 4130 rod. Using a slightly under matched filler metal gives better overall properties and just plain works a lot better . Use E70S2 Tig rod and call it a day.

6. Taper off amperage slowly to avoid crater holes that will turn into cracks later on.

Have you ever tried to bend a piece of 4130 Chromoly tubing? OMG! This stuff is harder than Japanese arithmetic. Compare it to 1010 steel as far as how hard it is to bend and there really is no comparison. Just get a piece of 1/2 inch tubing and try it. You will strain your left testicle trying to bend chromoly tubing.

There are other chromium molybdenum steels like 4140 and 4340 but one of the most common chromoly steels is 4130 chromoly steel.

Back in the day, chromoly tubing was welded with oxy-acetylene. Why?

Because it worked... and because that is what most shops had available. And then years later I am sure some old timer said "because that’s the way we have always done it" .

But research has been done to prove that Tig welding can be the fastest, cleanest and best way to weld 4130 chromoly tubing without risk of compromising material properties(provided the thickness does not exceed .120").
Wyatt Swaim (also known as Mister Tig or "Mr. Tig")
Wyatt Swaim (also known as Mister Tig or "Mr. Tig") has been promoting Tig welding of 4130 chromoly tubing for several years now and even holds seminars and workshops for EAA (experimental aircraft association) enthusiasts to get them acquainted with the TIG welding process. But what does the number 4130 mean? What does the term "chromoly" signify? What is it most used for and why? And what is so difficult about welding 4130?

Chromoly refers to a steel alloy which contains chromium and molybdenum among otherelements. The word ‘Chromoly’ is a short term for “Chromium-Molybdenum" steel. Thenumber ‘4130’ is a code of the American Iron & Steel Institute (AISI 4-digit codesystem) and defines the approximate chemical composition of the steel. The ‘41’indicates a low alloy steel containing chromium and molybdenum and the ‘30’ indicates acarbon content of 0.30 percent.(that’s 3/10ths or 30 one hundredths of a percent) 4130 is often used for high end bicycle frames and race-car roll cages due to its high tensile strength, malleability and easy weldability. In addition, it is considerably stronger and more durable than standard 1020 steel tubing, which is also known as "plain carbon steel".
More details on AISI numbering system for alloy steels
Alloy steels differ from carbon steels in that they have compositions that extend beyond the limits set for carbon steels. Usually this refers to constituents such as boron, carbon, chromium, manganese, molybdenum, silicon and vanadium. They also have chromium contents less than 4%. Steels with chromium contents of greater than 4% become classified as stainless or tool steels. As a general guide, an alloy steel will have:

• Manganese content >1.65%

• Silicon content >0.5%

• Copper content >0.6%

The American Iron and Steel Institute (AISI) naming system is one of the most widely accepted systems.

Designations usually consist of a four digit number, but sometimes this extends to five. The first two digits indicate what the major alloying element is, while the last 2 or three indicate the carbon content in hundredths of a percent.

Example: AISI 4340 is a Nickel,Chromium,Molybdenum containing alloy steel with a 0.40% average carbon content.there also something called a "carbon equivalent formula" that basically calculates the effect that elements like chromium and vanadium etc. have on the hardenability of a steel. In other words, because aisi 4340 has 0.4% carbon but also has around 0.8% chromium, the hardenability might be the equivalent of a plain carbon steel having 0.5% Carbon.

The American Iron and Steel Institute has a numbering system for steels and the 4100 series indicates a chromium molybdenum steel. The "30" in 4130 indicates 0.3% carbon. 4130 also contains 0.4 to 0.6% manganese, 0.8 to 1.1% chromium, 0.15 to 0.25% molybdenum, 0.04% phosphorus, 0.04% sulfur, and 0.2 to 0.35% silicon, but like all steels, it is mostly iron. 4130 chromoly is an ideal material for BMX bicycle frames, roll cages for race cars, and for fuselages on small aircraft because of its high tensile strength and high strength-to-weight ratio.

Welding 4130 is not that much different than welding steel or stainless steel as far as technique is concerned. There are just additional considerations to keep in mind.

Remember...

watch your arc strikes,

dont speed cool,

use E70S2 tig welding rod,

pay attention to good fit ups,

weld a little slower,

use a little preheat if it is chilly in the shop,

taper off your amperage to avoid crater cracks.

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