Float vs detent?

[plowhog]

Can you help me understand float vs detent for the rear remotes? I want to operate a box scraper, and a hydraulically controlled landscape rake / blade combo.

In theory I know that a "float" can let the box scraper drag across the ground just using gravity. But I'm confused if I need one "float" or two to achieve this? The dealer says just one float, and two detents is fine ...

 

[RedNeckRacin]

Float is a detent on the control lever generally associated with the loader control or scv for the rear remotes. The 3pt has no down pressure so it naturally "floats" up but not down past the set position. Hope that helps.

Operating ground engaging implements with the scv in the float detent is generally not good operating practice. You generally adjust the angle or pitch or offset of the implement and leave it be until you want to adjust again. If you ran it in float detent, it would be impossible to grade with.

scv- selectable control valve

 

[/pine]

Also....the word "detent" generally refers to a mechanism that will hold the spool lever from returning to center...if it is a non=float detent fluid will continue to flow through that circuit at status pressure while engaged...this is often used when powering something like a log splitter w/own svc, winch etc from the rear remotes...

 

[1stDeuce]

RedNeckRacin, you can't use float and detent to describe float and detent.

Pine has it right for detent. It means the lever will stay where you put it in some position. For remotes, that usually means it'll flow one way or the other, continuously, until you pull the lever back to the middle position, at which point hydraulic flow is stopped, and held. This is usually used for running a backhoe, or a logsplitter, or some other thing that would require continuous flow. It is NOT useful for hydraulic cylinders, as it'll just fully extend or retract them, then put the system into pressure relief until you pull it out of the detent position.

A "floating" remote should have a position that allows fluid to flow, so it can't lock a hydraulic cylinder in place. This would be for ground following, as you guess... I'm not really sure how this is done... Is it the middle position, so the remote is incapable of locking a cylinder? That doesn't seem right, so it's probably like the loader, where there's a position past the normal movement that "detents" and places it into a float mode, while normal movement would control the cyl, and the middle would lock it. ??

I believe the most common remotes would be non-float, non detent. That will lock cylinders in position in the middle, and move them when pushed fore or aft, but the lever will return to the middle if you release it in either position.

 

[s219]

For box blade, rear blade, grading use with hydraulic top link and side link, I'd say at least one valve with float (float is the detent) and one valve can be standard double-acting (no detent). Third valve can be whatever you want, or no third -- would be rare to need a third for grading work.

I'd only suggest a double-acting with detent if you plan to run some hydraulic equipment that needs continuous flow. Be mindful that the flow rate on the tractor may not be a whole lot.

 

[Ford850]

Can you help me understand float vs detent for the rear remotes? I want to operate a box scraper, and a hydraulically controlled landscape rake / blade combo.

In theory I know that a "float" can let the box scraper drag across the ground just using gravity. But I'm confused if I need one "float" or two to achieve this? The dealer says just one float, and two detents is fine ...

I think they mean one float (in detent), and 2 self centering valves. That sounds right to me. I have 3 self centering remotes on mine, but I could see that having a detent position for float on one of them would be helpful at times for the top link.

 

[1stDeuce]

So for those of you with a remote with float, it's the same as a self-centering remote, but has a detent past the normal range of travel that is "float"? Good to know! And sounds like a good setup to have at least one of.

 

[SPYDERLK]

For box blade, rear blade, grading use with hydraulic top link and side link, I'd say at least one valve with float (float is the detent) and one valve can be standard double-acting (no detent). Third valve can be whatever you want, or no third -- would be rare to need a third for grading work.

I'd only suggest a double-acting with detent if you plan to run some hydraulic equipment that needs continuous flow. Be mindful that the flow rate on the tractor may not be a whole lot.

As implied, some remote valves are detented for every position. The ones on the Mahindra 7520 are this way. -- Feathering control action happens before the detent engages. Overpressure in detent returns the valve to center. Float position builds no pressure so it isnt an issue for that function.

 

[MtnViewRanch]

As implied, some remote valves are detented for every position. The ones on the Mahindra 7520 are this way. -- Feathering control action happens before the detent engages. Overpressure in detent returns the valve to center. Float position builds no pressure so it isnt an issue for that function.

Larry, on our 7520s, (which by the way are far better valves than any other valve that I have seen on under 100HP machines) are actually 5 position valves. Float mode is all the way forward, then the std 3 locations for spring return to center operation and the 5th, all the way back which is a self canceling position. When the cylinder reaches the end of it's stroke the valve automatically kicks off and back to the closed (center) position.

For those of you that have a detent position, typically these valves are intended to be used as a fluid supply source for implements that have their own controls on the implement such as a log splitter or back hoe. Again typically the control lever does not spring back to neutral (closed) position. You have to manually put the lever in each position.

Each type of valve has it's purpose and costs are a bit different with the std spring return to center type valve being the most economical.

 

[SPYDERLK]

Larry, on our 7520s, (which by the way are far better valves than any other valve that I have seen on under 100HP machines) are actually 5 position valves. Float mode is all the way forward, then the std 3 locations for spring return to center operation and the 5th, all the way back which is a self canceling position. When the cylinder reaches the end of it's stroke the valve automatically kicks off and back to the closed (center) position.

They are great valves alright!​

Im not sure of you terminology but from ~ action mine seem different. My spring returns are F/B [1,2] and adjacent to center. These act proportionally up to full flow just before the respective F/B [3,4] detent points [which pressure/?self cancel]. Float [5] is all the way forward past the front detent as you say.

Our numbering is obviously different, but to me the "all the way back" :confused2: it.​

 

[Farmer495]

Have detent and float valves on M7040SU. detent was factory, float was added.

The detent valve is a self cancelling end of stroke, i.e. pull lever back and lock it, it pops back to neutral once your cylinder fully extends or retracts. 5 positions (retract lock, retract, neutral, extend, extend lock)
I haven't tried it on woodsplitter yet, but bet I'd have to tie the lever back.

Float valve is what you want if you have anything with single acting cylinder. I use it for a dump wagon and disc mower. I pfrefer using it to the detent style since it's easier to feather and go max flow without hitting the very aggressive detent, float valve feels similar to loader joystick and has 4 positions, (float, retract, neutral, extend)

If you are getting 2 extra valves, I'd get 2 floats just for the lever feel alone, the "1st" valve must be a detent, at least according to the instructions with the M7040SU kit, the other 2 can be 2x float, 2x detent or one of each.

I like the valve on the CIH 495 best, 6 position (float, retract lock, retract, neutral, extend, extend lock) No aggressive detent, have lock lever to run wood splitter or it self cancels when the splitter gets to end of stroke.

 

[ovrszd]

Have detent and float valves on M7040SU. detent was factory, float was added.

The detent valve is a self cancelling end of stroke, i.e. pull lever back and lock it, it pops back to neutral once your cylinder fully extends or retracts. 5 positions (retract lock, retract, neutral, extend, extend lock)
I haven't tried it on woodsplitter yet, but bet I'd have to tie the lever back.

Float valve is what you want if you have anything with single acting cylinder. I use it for a dump wagon and disc mower. I pfrefer using it to the detent style since it's easier to feather and go max flow without hitting the very aggressive detent, float valve feels similar to loader joystick and has 4 positions, (float, retract, neutral, extend)

If you are getting 2 extra valves, I'd get 2 floats just for the lever feel alone, the "1st" valve must be a detent, at least according to the instructions with the M7040SU kit, the other 2 can be 2x float, 2x detent or one of each.

I like the valve on the CIH 495 best, 6 position (float, retract lock, retract, neutral, extend, extend lock) No aggressive detent, have lock lever to run wood splitter or it self cancels when the splitter gets to end of stroke.

Very good description of Kubota's setup.

I know SCV as Self Cancelling Valve, as you described.

I have one SCV and two Float valves. I run my TnT with the two floats. The SCV is used on my hydraulic scarifier BB and on my tandem wheeled disc.