Controlling Speed

[winesalot]

When I finally buy my tractor one of the uses will be spraying a vineyard. I am planning on a PTO driven 3-Point mounted sprayer. To properly calibrate the sprayer I will need a set, consistent, and repeatable pto rpm and rolling speed on the Kubota. Is this possible and how would I accomplish it with the HST transmissions?

 

[CountryBumkin]

Setting the throttle position and keeping it in the same position will keep the rpm and PTO speed constant while spraying.

You didn't say what model tractor you have, but if it is a BX with the cruise control, you could set your ground speed with the HST pedal then lock the cruise control to maintain that ground speed. If you don't have a cruise control you might try putting tractor in turtle mode (low-low) and running with HST pedal fully depressed (to maintain same ground speed).

 

[1970cs]

Grand L series have a speedometer and cruise control. I don't believe that Kubota has a narrow or vineyard in a Grand L You need to do a small test plot to see if your flow rate and spray nozzle size is correct for what you are doing.

Depending on the ground speed that is required you could also go with a GPS speedometer but they are not entirely accurate below 3 MPH.

B2320N is a narrow tractor which has cruise.

Pat

 

[1970cs]

Grand L series have a speedometer and cruise control. I don't believe that Kubota has a narrow or vineyard in a Grand L You need to do a small test plot to see if your flow rate and spray nozzle size is correct for what you are doing.

Depending on the ground speed that is required you could also go with a GPS speedometer but they are not entirely accurate below 3 MPH.

B2320N is a narrow tractor which has cruise.

Pat

 

[sheepfarmer]

I was playing around with the cruise control on my HST 3560 a couple days ago while mowing, and I believe it would do what you want. The throttle is set to get pto speed of 540, and the ground speed is determined by gear range selected and pressure on the pedal. When you push the toggle to engage the cruise control the screen displays both the rpm and what they are calling "pedal step on rate" , eg 30%. The switch can be touched lightly to ratchet the speed up or down incrementally, so I think you could replicate the ground speed again by looking at this screen after stopping as long as the gear range stays the same. The screen stays on for about 10 sec, but should be reactivated every time you touch the button. The next time I mow I'll check.

 

[Grouse Feathers]

Another option would be to use a digital tach with a proximity probe. The proximity probe will generate a signal for the digital tach every time a magnet passes the probe. The magnet could be mounted to the exposed axle or one of the wheels. The probe would be mounted close enough to detect the magnet. If the rpm range is to low you could use two or more magnets. You just want to have a repeatable indication and the actual ground speed or rpm doesn't matter.
Here is one digital tach with a proximity probe on Amazon:
https://www.amazon.com/DIGITEN-Digi...TF8&qid=1468866754&sr=8-25&keywords=rpm+gauge

 

[winesalot]

To answer one question, I do not have a tractor yet. This all in the name of through research before I make a decision.

At my previous job I had a small John Deere (sorry for the cuss word on this site) that had a manual transmission which is what I used for all of my spraying. All of our other machines had the hydrostatic and I could never figure out how to be consistent with my speed.

I like the ideas posted here.

 

[boz1989]

My brother once glued a magnet to the rim of his quad, then used a bicycle computer for a speedometer. For about $20 it worked good at lower speeds, when he cleared 40mph, is started to get flaky.

Sent from my LGMS330 using Tapatalk

 

[scdeerslayer]

That's one of the reasons I bought a gear tractor.

My brother once glued a magnet to the rim of his quad, then used a bicycle computer for a speedometer. For about $20 it worked good at lower speeds, when he cleared 40mph, is started to get flaky.

Sent from my LGMS330 using Tapatalk

Tractor wheels would probably be too slow for that at working speed.

 

[Grandad4]

It may depend on just how precise your application rate needs to be. If you need very high precision, a simple gear tractor makes it easy to reproduce the same ground speed. The new hi-tech HST setup on the Grand L models achieves the same thing, along with a whole bunch of other capabilities. So that's a high-end solution.

Someplace in between are conventional HST drive setups that don't give you much beyond a seat-of-the-pants sense of ground speed. That has worked OK for my occasional herbicide spraying, where my being perhaps within + or - 20% of, say, a 4 mph target speed is acceptable. But I'd suspect you need more precision than that.

Some other interesting ideas here for speed measuring, also. You might also explore some of the precision ag spraying suppliers. Don't know if one of them has anything reasonable affordable for your needs.

 

[Cousin Eddie]

My 4701 HST has CC and also an adjustable bolt under the pedal that stops it at a certain point. If you set that where you need it, you could pick a gear range and just push it all the way down. That would make you speed consistent and repeatable. You could also just find the right thickness wood block and secure it to the bottom of the pedal. Cheap and simple CC.

 

[Kurtee]

Take a look here. These people build controls that control application rates by actual speed. Any tractor will work and speeds are not important allowing you to use the speed right for where you are at.

http://micro-trak.com/

 

[rjcorazza]

On my previous L3410HST, I measured ground speed with a watch and known distance with the pedal fully depressed in each range and at several rpm settings. My sprayer was electric, so the rpm could be a variable. I like the idea posted above about using a wood block limiter for the pedal.
The new L4060 has the cruise control and speedometer, so whatever gear or rpm combination I happen to be at (within the limits of the gear range) I can set my desired speed.
Application rates are complicated enough without having to guess on speed.