JD Sq Baler PTO/Flywheel Ratio Solved.....

Bill VA

Well-known Member
Spent a little time tinkering with the 348 today and wanted to answer the question - does the JD square baler have any gear reduction from the PTO drive to the flywheel.

Here's what I found - give or take a few degrees:

1 full turn of the PTO shaft (measured on the gear box side of the slip clutch) equals about 315 degrees of a flywheel turn.

Which is a 1 to .875 ratio (or maybe the opposite - long day.... )

So the answer is - YES - there is some gear reduction to the flywheel. Maybe this accounts for JD's lower hp requirements for the baler.

It would be great if other JD square baler owners could measure the PTO to flywheel ratio for their baler and post it with the corresponding baler model.

Bill
 
You did it the hard way.

A quick look at the 348 parts catalog shows an 18 tooth gear driving a 21 tooth gear, for a gear reduction of 1 : 0.857.

Just for the heck of it I looked at the 336 and 346 PC's and tooth counts are NOT given. 338 shows 16 tooth driving 22 tooth, for a gear reduction of 1 : 0.73.
 
(quoted from post at 22:24:27 02/20/16) You did it the hard way.

A quick look at the 348 parts catalog shows an 18 tooth gear driving a 21 tooth gear, for a gear reduction of 1 : 0.857.

Just for the heck of it I looked at the 336 and 346 PC's and tooth counts are NOT given. 338 shows 16 tooth driving 22 tooth, for a gear reduction of 1 : 0.73.

On NH balers the reduction gear is on the side. How is positioned on a JD baler since the flywheel is already mounted on the side of the bale chamber?
 
On NH baler flywheel is ahead of reduction, and on JD baler flywheel is beyond reduction. Also, different ratio is what determines different baler strokes per minute. There is another 5:1 (+/-) reduction somewhere as well to get to SPM which is really RPM of plunger crankshaft
 
(quoted from post at 08:56:46 02/21/16) On NH baler flywheel is ahead of reduction, and on JD baler flywheel is beyond reduction. t

IMHO JD baler is also ahead of gear reduction. I've never attempted to count JD flywheel revolutions per minute but I think flywheel turns faster than 93 RPM's on a 347. Flywheel mounts on a hub that mounts on shaft(parts key 17)

33120.jpg
 
(quoted from post at 00:24:27 02/21/16) You did it the hard way.

A quick look at the 348 parts catalog shows an 18 tooth gear driving a 21 tooth gear, for a gear reduction of 1 : 0.857.

Just for the heck of it I looked at the 336 and 346 PC's and tooth counts are NOT given. 338 shows 16 tooth driving 22 tooth, for a gear reduction of 1 : 0.73.

That's not the only place reduction takes place as there's difference in number of teeth on shaft(parts key 17) & gear(parts key 4) in previous photo.
 
A few thoughts:

Not that gear reduction, flywheel on the side of the baler vs front/direct mounted to the PTO shaft at the end of the day make or break a baler design, but interesting to me none the less....

One thing for certain is work is work no matter how you slice it. If different balers are pounding out 3 inch flakes of hay into a bale at the same strokes per minute, then ideally it takes the same amount of work to compress the bale. Everything hp wise added to that effort from the plunger face back to the tractor PTO shaft adds to the power requirements. Efficiency in design comes to mind.

For example, is the knife design or auger/feeder system, etc., more efficient and does that translate into more hp required? Is a 93 stroke per minute baler like the JD348 more efficient in that it's minimum hp requirement 35 vs the New Holland BC5070 which I believe is over 65 hp - I doubt it.

With out a doubt on my 348, the flywheel does not make one complete revolution for every complete revolution of the PTO shaft. Does that mean a lower hp tractor tractor can be used? Maybe - to some extent.

IMHO once the flywheel on any baler is up to speed, the split second the plunger hits the charge of hay, almost all of the energy to mash the hay is in the flywheel. The drive of the PTO would contribute some to as it isn't disconnected, but can slip with every stroke - or it's supposed to. However, IMHO the vast bulk of the energy to compress a bale is stored in the flywheel.

To me that means that work has to be done to return the flywheel to speed. If the connection is 1:1 from the PTO to the flywheel, then more momentary hp is required than a flywheel with a gear reduction. Since there is some time (albeit) very tiny, it is possible to get away with a smaller hp tractor on the JD.

OTOH - I also wonder if from the original 14T a gear reduction was part of the mix to reduce the load on the JD two cylinder tractors to even out the load and give a smoother operation. If that was the design intent, did it carry over to the current Deere balers?

Again, interesting topic to me....

Besides - it's cold and rainy here - got to talk about something... LOL!

YMMV

Bill
 

IMHO if NH & JD sq baler flywheels weighed the same then the faster spinning flywheel baler(NH) should require less HP to do the same chore as the JD
 
I agree Jim that the major reduction in the JD is beyond the flywheel, just as it is with the NH! I should have clarified that the right angle minor reduction was before on the JD but beyond on the NH. I'm not absolutely sure, but it would seem that the JD flywheel is both larger diameter and heavier, which would help to "even out" the HP demand.
 
One last thought, perhaps the fact that the NH flywheel turns minimally faster helps offset the greater bulk of the JD flywheel.
Perhaps we can get Uncle Sam to fund a grant to study this further! LOL, TIC, Dave
 
One more bit of info. the NH has only one reduction, not 2 as with the JD. The NH has a right angle gear box with all the reduction accomplished with one ring & pinion gear set, 540 RPM in & 93 RPM out. That would explain why the flywheel is mounted where it is.
 
My thought is that the gear reduction downstream of the flywheel is an unknown - kinda....

If the JD348 and New Holland 575 with plunger strokes at 93 per minute, as an example, then of course the purpose of the gear reduction past the flywheel is simply to get from PTO RPM to 93 RPMs plunger speed. If power required to make a bale is mostly stored in the flywheel, then downstream gear reduction doesn't necessarily help with input power from the tractor.

However, like the input shaft and the assist the tractor gives on each stroke beyond the flywheel energy, the plunger momentum would be considered stored energy too prior to slamming the hay into the bale.

But - I'm thinking that the ultimate power required by a baler is in the recovery - power required after the plunger slams home into the rear of the bale. If the ratio is 1:1 on the flywheel from the PTO - then more hp is required for the short time lapse back to full speed. If there is a gear reduction (think lower gear like a truck), then maybe it's possible not as much hp is required during the short recovery time.

How's that for an over thinking reply..... ;-)

Bottom line is - when reading about power requirements in some older posts, it has been pointed out occasionally that the gear reduction, ratio - whatever one wants to call it for the John Deere balers - PTO to flywheel via gearbox - maybe if someone does a search, as I have done, somewhere in the archives is a post that validates it - which this series of threads does.

Really to what extent it effects hp - maybe if I win the lottery, I'll commission a study - or maybe just buy a 100+ 4x4 tractor with AC and a nice stereo and forget about it.... :)

Bill
 
Bill VA is on the right track. The size (or rather the inertia) of the flywheel has no effect on total power. Whatever energy the flywheel uses to compress the bale has to be restored before the next stroke. All the flywheel does is smooth out the pulsations (and shock) to the driveline. To a point.

With no flywheel, however, that short-time burst of energy has to come from the PTO itself and likely might require a larger HP tractor than that required with a flywheel.
 
"With no flywheel, however, that short-time burst of energy has to come from the PTO itself and likely might require a larger HP tractor than that required with a flywheel."

If you think that would work, at all, try baling with the shear pin sheared!
 
I agree with all the talk of gear reductions on them, but I don't think it has one single thing to do with Deere's advertised 35hp minimum for the 348 baler. That is just Deere doing what they do best and bettering their marketing angle. Sure the 348 baler will bale hay with 35hp if you don't feed it too fast. Now they can market that baler to every hay producer that has at least 35hp. I don't think anybody, including the folks at Deere, think you'll get the full capacity of a 348 baler with only 35hp. NH is probably advertising a number closer to what is required to use their baler at rated capacity. I'm not knocking the Deere baler, that's my baler of choice, but the way they market stuff to get the biggest market share possible is sometimes a little misleading. Of course they're not technically being dishonest.

David
 
A bit more info on the JD input pinions from the PTO to flywheel. Here's a breakdown from JD's parts list for the following balers:

14T, 24T, 214, 224, 327, 328, 336, 337, 338 and 346 balers are 16 tooth to 22 tooth pinions for a 0.727 to 1 reduction ratio for the PTO shaft. How I got some of the tooth numbers for some of the missing was look at known tooth numbers and the corresponding part number for the pinion. Where a tooth part number was not shown, the part number for that pinion was - so referenced a like part number that showed the tooth count.

The 347 and 348 balers are 18 tooth to 21 tooth pinions for a .857 to 1 reduction ratio for every turn of the PTO shaft.

All other losses ignored - if a 35 hp tractor is used (and is JD's minimum recommended for the 348 - 40hp in the service manual), I believe as long as the flywheel RPMs have recovered between plunger strokes and is up to speed, then the flywheel inertia is capable of doing 35hp - divided by - the pinion ratio.

For a 336, that would be 35hp/.727 = 48.1 hp worth of flywheel power. If it were a 1:1 ratio PTO/flywheel baler, you'd need a 48ish hp tractor to do the same work.

For a 348, that would be 35hp/.857 = 40.8 hp worth of flywheel power. If it were a 1:1 ratio PTO/flywheel, you'd need 41ish hp tractor to do the same work.

The flywheel being an energy storage piece and as long as it's up to speed - you'll get the full potential of the baler. Recovery time is the hp driver. If the flywheel can't be returned to full RPMs for the next stroke, you need more tractor hp or settle for lower capacity from the baler.

IMHO - this input ratio is how JD in part justifies their minimum ratings.

Further - consider recovery time and strokes per minute. I think a 14T and 24T are similar in strokes per minute, maybe around 60? That would give a lower hp tractor more time to recover from the power stroke of the baler plunger and get the flywheel back up to speed and potential energy - yet require much less hp than a 348.

Interesting that a 14T and a 348 make a 14" x 18" cross-section bale and if the length is the same, i.e. at 36 inches and the flakes per bale were the same at 3 inches per flake - then the difference in power requirements is the availability of recovery time for the flywheel and with it - the hp required to run the baler.

However.....

Rain is coming and you're in a hurry. So you start slamming flakes that are 6 inches thick and pumping the bales out the back. If the power requirements for a flake thickness of hay were linear (a guess on my part), then one could argue that a 6 inch flake requires 2 times the hp to recover the lost inertia of the flywheel. So that 35 hp minimum could easily jump to 70 hp. Kind of where New Holland rates the minimum hp for their 575 and BC5070 balers.

I'm sure there has been more than one farmer that was ticked that his 35 hp tractor couldn't make maximum use of the capacity of their 347 or 348 baler after being told 35 hp was the minimum - even though he heard "minimum" from the get-go. OTOH - how could you be disappointed if you bought a New Holland and per the manual, put a 70 hp tractor in front the 575 and when the rain threatens - you're good to go.

I think I'm right or close to being right with the above - but PLEASE - someone correct me if I'm in error so that future post searchers won't be led astray with this post.

Thanks,
Bill
 

I am convinced its marketing that decided what tractors can power a 348 baler rather than potentially lose sales to farms with smaller tractors. Even a NH 575 will bale with a small tractor although will not work to anyhere near its full capacity.
 

Bill VA
All your calculations do not include the gears similar to parts keys 4 & 17 which are involved in reduction. Back when engines were an option on 346 balers the 16 & 22 tooth gears you mentioned weren't utilized to transfer power from engine to plunger head.

Can you please explain your statement about a 14T & 348 making a 36'' long bale both having 3'' flakes? I can't envision that being true if 348 is operating at 93 strokes per minute.

Back in the 70's I baled hay with a 214 pto baler utilizing a JD BO(14 hp) just to see if it would and it baled fine but didn't set any BPM pr BPH records

33214.jpg
 
I tried explaining this on an earlier post. Same baler.
I had it on a 5403 JD. The "weekend warrior"
tractors clutch's just don't hold up. This was spec at
63 hp. The 348 doesn't go on anything smaller than
a 4020 now. It will work with smaller tractor but it'll
beat the tar out of it.
 

I've baled hay with my 347 using a JD 2040(40 pto hp),Kubota M4900(45 pto hp) & Kubota M7040(65 pto hp) without any adverse affects to any of the tractors mentioned. Only reason I moved to higher hp tractor was because of the disc cutter not the sq baler.

FWIW JD 5000 utility tractor clutches don't have the best track record for reliability.
 
"All your calculations do not include the gears similar to parts keys 4 & 17 which are involved in reduction."

I view these gears down stream from the flywheel - they don't contribute to helping the input side of getting the flywheel get up to speed directly.
They are more of a drag on the flywheel, like the plunger IMHO.

"Back when engines were an option on 346 balers the 16 & 22 tooth gears you mentioned weren't utilized to transfer power from engine to
plunger head."

Good point. Don't think those gears are needed. Don't know if those old stationary engines ran at 1800 or 3600 rpms or something else, but I
should think the engine belt pulley and the flywheel diameter take care of any reduction for input - and were probably designed to maximize
engine to baler. IMHO, the slower 80 strokes per minute on the 346 is an advantage to engine/flywheel recovery time vs the 93 SPI on the
347/8 balers. In addition, the 346, if I recall correctly has the heavier flywheel like the 347/8 balers which ought to help with rpm dips when the
plunger strikes the bale when encountering a thicker flake of hay.

"Can you please explain your statement about a 14T & 348 making a 36'' long bale both having 3'' flakes? I can't envision that being true if 348
is operating at 93 strokes per minute."

When we first started making hay with our NH68, I could really jam some hay in the pickup and at full 540 RPM throttle, mash out some bales
quick - maybe not modern baler fast, but fast enough to bury the wagon stackers. What that got us was bales with 5-6 inch flakes and
inconsistency in the length. To fix this, I slowed the ground speed and we get around 15 flakes to a bale, that is 2-3 inch flakes. The length is
much more consistent, bale shape is much better too. I believe the 14T is 60 or 65 strokes per minute - similar to my 68. So what I'm saying is
- first, a 36 inch long bale is a target length for this example. It is made with 3 inch flakes of hay. For the 348 and 14T - like my 68, you'd have
to adjust your speed to achieve the 3 inch thick flakes.

One thing we are excited about with the 348 over our 68 is with the 93 strokes per minute, we can get those 3 inch flakes and have more output
at the same time. We are selling our hay to horse folks, so small flakes are important as is bale shape/appearance.

Thanks!
Bill
 
(quoted from post at 12:07:16 02/23/16) "All your calculations do not include the gears similar to parts keys 4 & 17 which are involved in reduction."

I view these gears down stream from the flywheel - they don't contribute to helping the input side of getting the flywheel get up to speed directly. Bill

I disagree I think gears(parts keys 4 & 17) help flywheel maintain momentum.
 
(quoted from post at 10:20:01 02/23/16)
(quoted from post at 12:09:48 02/23/16) Those engines probably had a lot of torque too!

I'll bet not more torque than a 70-95 HP diesel engine in a tractor.

Yep - we are on the same page there!
 
(quoted from post at 10:18:31 02/23/16)
(quoted from post at 12:07:16 02/23/16) "All your calculations do not include the gears similar to parts keys 4 & 17 which are involved in reduction."

I view these gears down stream from the flywheel - they don't contribute to helping the input side of getting the flywheel get up to speed directly. Bill

I disagree I think gears(parts keys 4 & 17) help flywheel maintain momentum.

Parts 4 and 17 are downstream of the flywheel and by themselves cannot add speed to the flywheel - and I doubt they have the relative mass to maintain momentum and in doing so help the flywheel. Their purpose is to directly link the flywheel to the crank arm and transition the flywheel rpms to an acceptable plunger speed - i.e. 93 SPM.

However, there is much mass between the crank, crank arm and plunger itself and that IMHO adds to the flywheel inertia when the plunger face strikes the bale of hay.

But once the face of the plunger hits the bale, all components back to the flywheel start acting like a break - how else could the flywheel slow down? Without some input power, everything must start to slow down. What this means is work is still required to return the plunger for another throw at the bale and that comes from the flywheel. Without an input power source, nothing can return the baler to operating RPMs - so we add an external power source, i.e. a tractor or stand alone motor. Even with an empty baler, the plunger consumes power through it's entire stroke. The inertia of the plunger, magnified by the flywheel IMHO is what causes the tractor to rock back and forth.

As I mentioned in an earlier post - the PTO hp required of a tractor for any given baler is the amount of hp required to get the flywheel (and everything connected to it down stream) back up to speed and maximum inertia for the next plunger compression stoke. Only the input shaft - connected to an external source can supply this power - nothing else.

So all of that to recap the purpose of the original post and my follow-up:

John Deere balers have a gear reduction going into the flywheel on the input side of the baler. The ratio is such that the PTO shaft completes a full turn before the flywheel does - on every John Deere baler. If there is time to recover flywheel speed with each plunger cycle, that time and the gear reduction is the mechanism that allows a potentially lower hp tractor to operate a Deer square baler.

If larger flakes are made - as the baler is pushed to it's limits - yes, more hp is required. But the gear reduction is favorable for a less hp tractor with a John Deere baler than another baler with the flywheel directly coupled to the PTO shaft and a 1:1 ratio. In no way is that a dig on any other make baler - I like all of them. But like I mentioned in another post, prior references had been made to "gear reduction" for Deere balers in some postings and I just wanted to validate that for future searchers - kind of got off track with it though - sorry about that.

I appreciate the dialog - more info is always good.

Thanks!
Bill
 
"As I mentioned in an earlier post - the PTO hp required of a tractor for any given baler is the amount of hp required to get the flywheel (and everything connected to it down stream) back up to speed and maximum inertia for the next plunger compression stoke. Only the input shaft - connected to an external source can supply this power - nothing else."

That is not true. It not only takes power to bring the baler back up to speed, but it takes power, in addition to the energy stored in the flywheel, to push the plunger when forming a bale. The more you push the baler the more hp it takes to form the bale. Bringing it back up to speed is the easy part. It takes a certain amount of power to pack so many tons of hay in a given time period. In the end, two balers making the same size and weight bale at the same rate are going to require roughly the same amount of hp regardless of how they're configured. There is no way around it.

David
 
(quoted from post at 20:23:47 02/23/16) "As I mentioned in an earlier post - the PTO hp required of a tractor for any given baler is the amount of hp required to get the flywheel (and everything connected to it down stream) back up to speed and maximum inertia for the next plunger compression stoke. Only the input shaft - connected to an external source can supply this power - nothing else."

That is not true. It not only takes power to bring the baler back up to speed, but it takes power, in addition to the energy stored in the flywheel, to push the plunger when forming a bale. The more you push the baler the more hp it takes to form the bale. Bringing it back up to speed is the easy part. It takes a certain amount of power to pack so many tons of hay in a given time period. In the end, two balers making the same size and weight bale at the same rate are going to require roughly the same amount of hp regardless of how they're configured. There is no way around it.

David

I would agree to that. But would suggest that once the plunger strikes the bale, the interval of time may be to short for the governor of the tractor's engine to recover and with it deliver additional force beyond the inertia of the flywheel. Maybe the flywheel doesn't play as much of a dominant role as I have suggested. I can tell you that in first hand testing of diesel powered electric generators, we "block" load them - which means we drop the full design electrical load on the generator at once. The goal in part is to ensure that the rpms don't drop such that it effects the frequency and voltage. It is a severe test. It is most difficult for engine to recover and not fail the test. The engine controls, electrical or mechanical are just not fast enough to respond. Maybe that same block load effect with a baler's plunger is different. I've seen generators struggle to recover from a block load such that the Diesel engine sounds like a bull dozer plowing into a dirt pile and easing up to recover - black smoke abounds.

I appreciate the response.

Bill
 
(quoted from post at 18:35:11 02/23/16)


I disagree I think gears(parts keys 4 & 17) help flywheel maintain momentum.

Parts 4 and 17 are downstream of the flywheel and by themselves cannot add speed to the flywheel -

However, there is much mass between the crank, crank arm and plunger itself and that IMHO adds to the flywheel inertia when the plunger face strikes the bale of hay.

But once the face of the plunger hits the bale, all components back to the flywheel start acting like a break - how else could the flywheel slow down?
Bill[/quote]

Parts 4 & 17 can add rpm's to flywheel in relation to PH speed.

What scientific evidence proves that flywheel slows significantly or even at all when hay is compressed. Have you aimed an electronic tachometer at flywheel while baling? I personally think flywheel ""doesn't slow down in normal baling operation"".
Jim
 
"Parts 4 & 17 can add rpm's to flywheel in relation to PH speed."

This is completely incorrect - but I'd like to hear your "scientific" explanation of how it could do so.

"What scientific evidence proves that flywheel slows significantly or even at all when hay is compressed. Have you
aimed an electronic tachometer at flywheel while baling? I personally think flywheel ""doesn't slow down in normal
baling operation"

Maybe the flywheel doesn't slow down at all. Next time you're out baling - you can take a measurement, let us know
and we won't be operating with a wild arse guess....
 
For all the fuss about HP requirements to compress the bale, I'm surprised no one mentioned how much easier it is to bale with SHARP closely-set knives and a well-adjusted plunger.

It obviously takes a fair amount of power to shear the hay at each plunger stroke.
 
(quoted from post at 07:42:42 02/24/16)

Maybe the flywheel doesn't slow down at all. Next time you're out baling - you can take a measurement, let us know
and we won't be operating with a wild arse guess....

Why not you do the measuring as you are the one not I that stated the flywheel slows down while baling hay?

PS: I don't own an electronic tachometer but If you'll send me one I will measure flywheel rpm's while baling. :lol:
 
Why not just watch the tractor tach? Everything from the tractor engine to the baler plunger is tied together mechanically!
Just as a point of interest, I notice more power dip when the belt thrower grabs a bale and launches it! I'm also inclined to agree with the idea that shearing off the wad of hay creates a goodly share of the resistance to the plunger travel. When a plunger stroke only takes 2/3 of a second, the whole thing doesn't have time to slow down or speed up very much!
Long story short, as I see it:
JD horsepower recommendations are based on operating the baler adequately, while NH horsepower recommendations are based on operating the baler to ultimate capacity. Further, I don't believe that there would be enough variation in power requirements between the two balers, doing the same amount of work, to even be a consideration!
JMHO, YMMV, Dave
 
This is a a great point.

A few other things come to mind too such as preventive maintenance - like greasing, pulling the plunger to make sure the plunger bearings are in fact rolling and are not seized and sliding along consuming unnecessary hp. I would think even properly aired-up tires would be of help.

If you're on the line with hp - maximizing the inertia of the flywheel by running full throttle at 540 rpms and going down a gear and/or unhitching the wagon from the baler would help.

I would think higher humidity hay is harder to bale than fully dried - so baling in those windows would be advantageous.

Beyond utilizing more hp than necessary, I should think there would be fuel savings too.

Thanks!
Bill
 
Jim - my email is open.

Send me you're address and I'll send you a tach.

Hopefully one of these days my business travels will take me through your neck of the woods - as I've met other YT members while on travel. It
would be great to put a face to a name and I'll buy lunch.

Take care & thanks!
Bill
 

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