What size plow?
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nspec
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Need more info. Size and weight of tractor, 2 OR 4wd, etc...
Farmwithjunk
Super Member
Depends....
(Ask me what time it is and I might tell you how to build a clock.....
)
Speed....Years ago, it was accepted that plowing speeds were something like 2 or 3 mph. Towards the late 50's early 60's, "high speed plows" came into fashion. That translates to 5MPH + or -. There are modern plows (more commonly used in Europe) that work well at speeds above 7 or 8 mph. The vast majority of 3-point "light draft" plows of 1, 2, or 3 bottoms that you'll find floating around in the used market were built in the era where "ideal" speeds were predominantly 4-1/2 to 5mph. The lions share of "economy" plows you'll find new these days are essentially copies of plows from the 60's and 70's.....(ie 5mph best speed to use)
Soil condition.....Hard clay or rocky soils won't plow like sandy, loamy bottom land.
Depth of plowing....As a rule of thumb, plows should be used at a depth of 1/2 the bottom width....ie 12" bottoms, 6".....14" bottoms, 7"....and so on. The WIDER the plow, the DEEPER it needs to operate to do the best job. With that in mind, there's a BUNCH of difference between 2X12's and 2X16's... I've seen tractors play with 3X12"'s and struggle with 2X16"'s....due mostly to soil compaction layer @ 7" or 8" that just wasn't a factor @ 6". Of course, with any "rule of thumb", there's a +/- factor....MOST plows will work fairly well 1" deeper or 1" shallower. In sod, all bets are off....EVERY experience I've had plowing sod, there's a sweet spot where depth = a good job turning and putting "green side down". Too deep and the cut doesn't roll over all the way. Too shallow and it'll throw the slice too far (as well as not working ground to a decent depth...)
Era the tractor came from....Old school thinking (pre wwII) was big heavy slow hulking tractors. 30hp on a 10,000lb slow beast would pull 3 or 4 bottoms in some instances. 30hp compact....not so much.
PTOhp or engine hp? I for one don't even consider engine hp a valid point of comparison. Who hooks any implement, pto OR drawbar directly to the flywheel? For the most part, farmers use pto hp as the benchmark.
A "typical" (whatever that is...) modern 30hp (pto) tractor of average weight should be able to pull 2X12" plows at a moderate speed in most conditions. 2X14"'s are a good trade off.... You can plow "shallow" for 14" bottoms @ 6", or sink 'em deep (for a 14") and work 8"+ in the right conditions. IMHO, it's a serious misjudgement to pile on weights and/or plow at ridiculously slow speeds in order to pull a plow that's essentially too big for the tractor. And, unless you're plowing hundreds of acres, there's not THAT much difference in time spent plowing with a smaller plow (at a decent speed) And THAT is easier on the tractor when all is said and done.
Plowing under ideal conditions is a piece of cake....Under tough or less than favorable conditions, it can be a black art of sorts.....
Long story short....unless there's something unusual about your "30 hp tractor", I'd recommend a 2X12, or at the largest, 2X14.....
(Ask me what time it is and I might tell you how to build a clock.....
)Speed....Years ago, it was accepted that plowing speeds were something like 2 or 3 mph. Towards the late 50's early 60's, "high speed plows" came into fashion. That translates to 5MPH + or -. There are modern plows (more commonly used in Europe) that work well at speeds above 7 or 8 mph. The vast majority of 3-point "light draft" plows of 1, 2, or 3 bottoms that you'll find floating around in the used market were built in the era where "ideal" speeds were predominantly 4-1/2 to 5mph. The lions share of "economy" plows you'll find new these days are essentially copies of plows from the 60's and 70's.....(ie 5mph best speed to use)
Soil condition.....Hard clay or rocky soils won't plow like sandy, loamy bottom land.
Depth of plowing....As a rule of thumb, plows should be used at a depth of 1/2 the bottom width....ie 12" bottoms, 6".....14" bottoms, 7"....and so on. The WIDER the plow, the DEEPER it needs to operate to do the best job. With that in mind, there's a BUNCH of difference between 2X12's and 2X16's... I've seen tractors play with 3X12"'s and struggle with 2X16"'s....due mostly to soil compaction layer @ 7" or 8" that just wasn't a factor @ 6". Of course, with any "rule of thumb", there's a +/- factor....MOST plows will work fairly well 1" deeper or 1" shallower. In sod, all bets are off....EVERY experience I've had plowing sod, there's a sweet spot where depth = a good job turning and putting "green side down". Too deep and the cut doesn't roll over all the way. Too shallow and it'll throw the slice too far (as well as not working ground to a decent depth...)
Era the tractor came from....Old school thinking (pre wwII) was big heavy slow hulking tractors. 30hp on a 10,000lb slow beast would pull 3 or 4 bottoms in some instances. 30hp compact....not so much.
PTOhp or engine hp? I for one don't even consider engine hp a valid point of comparison. Who hooks any implement, pto OR drawbar directly to the flywheel? For the most part, farmers use pto hp as the benchmark.
A "typical" (whatever that is...) modern 30hp (pto) tractor of average weight should be able to pull 2X12" plows at a moderate speed in most conditions. 2X14"'s are a good trade off.... You can plow "shallow" for 14" bottoms @ 6", or sink 'em deep (for a 14") and work 8"+ in the right conditions. IMHO, it's a serious misjudgement to pile on weights and/or plow at ridiculously slow speeds in order to pull a plow that's essentially too big for the tractor. And, unless you're plowing hundreds of acres, there's not THAT much difference in time spent plowing with a smaller plow (at a decent speed) And THAT is easier on the tractor when all is said and done.
Plowing under ideal conditions is a piece of cake....Under tough or less than favorable conditions, it can be a black art of sorts.....
Long story short....unless there's something unusual about your "30 hp tractor", I'd recommend a 2X12, or at the largest, 2X14.....
nspec
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Great answer!! Can't really add anything more constructive to that.
Farmwithjunk
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MHarryE
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Last year I had a 31 PTO HP Kubota and easily pulled 2 x 14s. This year the soil is like concrete due to weather conditions and it is a hard pull for my 50 PTO HP Kubota. The 2 guys I help do serious farming are both having problems. When I had my smaller tractor I kept a 1 x 16 plow around for years like this.