Front loader for a B7200

[TheOldHokie]

Don't know about the simultaneous flow, I guess I can check by operating both the raise/lower and curl/dump levers together and see if both things move ?

I saw what looked like a pretty neat and tidy joystick setup in a Ask Tractor Mike video and thought I might try to copy it - see pic below. I bought 3 ball ends, just need to make the rest.

It can get complicated.

Generic Monoblock Valves

In a typical two spool monoblock valve both spools are connected to the pressure source in parallel. When you activate them simultaneously the spool "pushing" the least load will get the lions share of the flow and the spool with the heavier load will stall.

EXAMPLE

If lifting a heavy load while dumping bucket the lift function will stall until the dump cylinder hits end of stroke or the bucket spool is returned to neutral

Kubota Loader Valves

Kubota loader valves are different. The boom spool is in series with the bucket spool. The oil returned by the boom work circuit is sent to the neutral inlet of the bucket spool. In the example above the boom and bucket cylinders get connected in series and both will move together seamlessly regardless of the differing individual loads.

Multiple Valves in Series

When you connect two single spool monoblock valves with PB in series you get an entirely different result. Activating the upstream valve closes the neutral (PB) circuit, redurects all incoming oil to the cylinder and oil returned by the cylinder is sent to tank. The downstream valve is completely cutoff from the pressure source and is dead in the water until the upstream valve is returned to neutral. Thats why you dont want two single spool valves for a loader.

Dan

 

[Paul Allwood]

It can get complicated.

In a typical two spool monoblock valve both spools are connected to the oressure source in parallel. When you activate them simultaneously the spool "pushing" the least load will get the lions share of the flow and the spool with the heavier load will stall. For example if lifting a heavy load while dumping the lift function will stall until the dump cylinder hits end of stroke or the bucket spool is returned to neutral

Kubota loader valves are different. The boom spool is in series with the bucket spool. The oil returned by the boom work circuit is sent to the neutral inlet of the bucket spool. In the example above the boom and bucket cylinders get connected in series and both will move together seamlessly regardless of the differing individual loads.

When you connect two single spool monoblock valves with PB in series you get an entirely different result. Activating the upstream valve closes the neutral circuit and redurects all incoming oil to the cylinder and oil returned by the cylinder is sent to tank. The downstream valve is completely cutoff from the pressure source and is dead in the water until the upstream valve is returned to neutral. Thats why you dont want two single spool valves for a loader.

Dan

Thanks Dan. Makes sense.

 

[Paul Allwood]

This afternoon I tested the loader lifting a load. I still don't have a bucket so I strapped increasing numbers of concrete sleepers to the SSQA frame.

I also don't have any rear ballast yet so I only lifted about 2 feet - not far back to the ground if I needed to hit the down arrow.

Having never owned or used a tractor before, and having never built anything like this before, I really wasn't sure what it would do. All the calculations and theory said it should be ok, but....

It actually worked .

I was aiming to see how close I could get to the B7200 rated lift capacity of 272 kg (600 lb).

I added 61 kg (134 lb) concrete sleepers one at a time until I got to 5 sleepers - 305 kg (671 lb). This was done at 1500 rpm with about 500 psi while raising.

How do I determine how much ballast to use ? I'll probably make a steel box that attaches to the 3 point link and add/remove gravel.

Does the 272 kg lift rating include anything attached to the end of the arms ? SSQA adaptor, bucket....or does their weight need to be subtracted from the rated lift capacity ?

 

[Hugo Habicht]

Hello Paul,

I am following your thread with great interest and I am admiring the work you are doing and what you have achieved in such short time frame

How do I determine how much ballast to use ? I'll probably make a steel box that attaches to the 3 point link and add/remove gravel.

You can look at the tractor as a lever with the front axle as the fulcrum. The ratio between the length from bucket to front axle divided by the length from front axle to rear weight multiplied by the bucket weight is the rear weight you need to get the same rear axle load as before. Adding weight reduces the front axle load, but within reason, you do not want the front axle to lift when the bucket is empty

Kind regards,
Hugo

 

[Paul Allwood]

Hello Paul,

I am following your thread with great interest and I am admiring the work you are doing and what you have achieved in such short time frame



You can look at the tractor as a lever with the front axle as the fulcrum. The ratio between the length from bucket to front axle divided by the length from front axle to rear weight multiplied by the bucket weight is the rear weight you need to get the same rear axle load as before. Adding weight reduces the front axle load, but within reason, you do not want the front axle to lift when the bucket is empty

Kind regards,
Hugo

Thanks Hugo, I'll give that a try.

 

[TheOldHokie]

Thanks Hugo, I'll give that a try.

My B7200/B1630 combo was generally fine with loaded rears and a -300# blade on the 3pt.

Long objects like logs will get you in trouble well before 600 lbs. Tractor tip overs are sideways events and when one rear comes off the ground you are over the line. Thats real life experience talking.

Dan

 

[torch]

Don't know about the simultaneous flow, I guess I can check by operating both the raise/lower and curl/dump levers together and see if both things move ?

I saw what looked like a pretty neat and tidy joystick setup in a Ask Tractor Mike video and thought I might try to copy it - see pic below. I bought 3 ball ends, just need to make the rest - hopefully not too ungainly .

Yeah that looks pretty much like what's under my rubber boot. The top of the spools are drilled to accept the mechanism. Yours may be different, necessitating some sort of adapter to attach the mechanism to the spools -- that's what I meant by "ungainly".

 

[TheOldHokie]

Yeah that looks pretty much like what's under my rubber boot. The top of the spools are drilled to accept the mechanism. Yours may be different, necessitating some sort of adapter to attach the mechanism to the spools -- that's what I meant by "ungainly".

Is it worth the time and expense when you can buy one for $275?

Hydraulic Directional Control Valve for Tractor Loader w/ Joystick, 2 Spool (Single Float Spool Optional), 11 GPM

This Monoblock Hydraulic Directional Control Valve uses a Joystick, 2 Spools and has a capacity of 11 GPM. These valves are used to start and stop fluid flow into hydraulic cylinders or hydraulic motors.

summit-hydraulics.com

Dan

 

[Paul Allwood]

Is it worth the time and expense when you can buy one for $275?

Hydraulic Directional Control Valve for Tractor Loader w/ Joystick, 2 Spool (Single Float Spool Optional), 11 GPM

This Monoblock Hydraulic Directional Control Valve uses a Joystick, 2 Spools and has a capacity of 11 GPM. These valves are used to start and stop fluid flow into hydraulic cylinders or hydraulic motors.

summit-hydraulics.com

Dan

Haha, thanks Dan, interesting question. I like to make things and I have plenty of time. Sometimes I might save a lot of money doing it, sometimes I might not save any.

I'm new to tractors so don't know exactly what will be useful from experience, just going by what I've read in spots like this and what I've watched on YouTube videos.

I went with a 3 spool valve to give me a 3rd function without any further mods except for hoses as I'll probably make a grapple, maybe a 4-in-1 bucket ??? I'll just leave the 3rd spool ports plugged until I'm ready. The valve spools are standard-float-standard, also thinking that the float function might come in handy but don't really know yet. I'd rather allow for it now and not need it than really wish I had it later.

Going this way with the valve meant that the local hydraulic supplier couldn't get one with a joystick to operate the first 2 spools. Hence the joystick conversion.

Is this the easiest or best way to go about it ? Maybe/maybe not, but no idea really. If there are alternatives, it won't change what I've done, but I'm always keen to learn.

Somewhere here someone asked why I bought the tractor. One of the reasons was to use it, initially to mow, then more. The other reason was to make things for it.

 

[TheOldHokie]

Haha, thanks Dan, interesting question. I like to make things and I have plenty of time. Sometimes I might save a lot of money doing it, sometimes I might not save any.

I'm new to tractors so don't know exactly what will be useful from experience, just going by what I've read in spots like this and what I've watched on YouTube videos.

I went with a 3 spool valve to give me a 3rd function without any further mods except for hoses as I'll probably make a grapple, maybe a 4-in-1 bucket ??? I'll just leave the 3rd spool ports plugged until I'm ready. The valve spools are standard-float-standard, also thinking that the float function might come in handy but don't really know yet. I'd rather allow for it now and not need it than really wish I had it later.

Going this way with the valve meant that the local hydraulic supplier couldn't get one with a joystick to operate the first 2 spools. Hence the joystick conversion.

Is this the easiest or best way to go about it ? Maybe/maybe not, but no idea really. If there are alternatives, it won't change what I've done, but I'm always keen to learn.

Somewhere here someone asked why I bought the tractor. One of the reasons was to use it, initially to mow, then more. The other reason was to make things for it.

I like making novel things - not so much re-inventing the wheel.

You definitly want float on the boom spool. Had you asked I would have recommebded that joystick valve with float for the loader and an electric valve for the third function.

The electric valve is something you can definitly save $$$ by rolling your own.

Dan

 

[Paul Allwood]

I like making novel things - not so much re-inventing the wheel.

You definitly want float on the boom spool. Had you asked I would have recommebded that joystick valve with float for the loader and an electric valve for the third function.

The electric valve is something you can definitly save $$$ by rolling your own.

Dan

It's looking like I would have been better to ask here rather than at my local hydraulic shop.

With an electric 3rd function valve, would it be operated from a switch on the joystick handle ?

I'll Google 3rd function electric valves, then might have more questions if that's ok.

 

[TheOldHokie]

It's looking like I would have been better to ask here rather than at my local hydraulic shop.

With an electric 3rd function valve, would it be operated from a switch on the joystick handle ?

I'll Google 3rd function electric valves, then might have more questions if that's ok.

Questions are always OK!! Yjsts whyvwe are here.

The reason for electric is to put all three functions on the joystick for one hand operation. Here is a cheapie.

https://a.co/d/hXhGq2x

Dsn

 

[Paul Allwood]

Questions are always OK!! Yjsts whyvwe are here.

The reason for electric is to put all three functions on the joystick for one hand operation. Here is a cheapie.

https://a.co/d/hXhGq2x

Dsn

Thanks Dan.

Sometimes I feel like a nuisance asking too many questions. Like I've got to have made a certain amount of progress before I qualify.

 

[TheOldHokie]

Thanks Dan.

Sometimes I feel like a nuisance asking too many questions. Like I've got to have made a certain amount of progress before I qualify.

There sre multiplecways to learn. One is the hardxway - frim misrajes. The easy way is asking questions and avoiding as msny mistakes as possible.

Dan

 

[Paul Allwood]

There sre multiplecways to learn. One is the hardxway - frim misrajes. The easy way is asking questions and avoiding as msny mistakes as possible.

Dan

So worst case, I use the 3rd function to operate a grapple or something else with a separate lever. Or I adapt solenoid coils that are on electric valves to my 3rd spool ?

 

[TheOldHokie]

So worst case, I use the 3rd function to operate a grapple or something else with a separate lever. Or I adapt solenoid coils that are on electric valves to my 3rd spool ?

No - you don't modify the 3 spool valve!!!

The 3rd spool on your manual valve will work fine for a third function just as you planned. An electric valve/joystick combo just allows one hand operation of all loader functions and is more user friendly.

At this point if you wanted you could add an electric valve to the circuit and use it and your DIY joystick for 3rd function. Thats how 3rd function is generally done.

You could then repurpose the third manual spool for something else like rear remotes.

If you wanted to go Full Monty eith the hydraulucs you could buy a new joystick loader valve and an electric third function for the loader. Then move the 3 spool to the rear for rear remotes. Thats a standard configuratuon using all off the shelf components.

NO CUSTOM MODIFICATIONS REQUIRED!!!

Dan

 

[Paul Allwood]

No - you don't modify the 3 spool valve!!!

The 3rd spool on your manual valve will work fine for a third function just as you planned. An electric valve/joystick combo just allows one hand operation of all loader functions and is more user friendly.

At this point if you wanted you could add an electric valve to the circuit and use it and your DIY joystick for 3rd function. Thats how 3rd function is generally done.

You could then repurpose the third manual spool for something else like rear remotes.

If you wanted to go Full Monty eith the hydraulucs you could buy a new joystick loader valve and an electric third function for the loader. Then move the 3 spool to the rear for rear remotes. Thats a standard configuratuon using all off the shelf components.

NO CUSTOM MODIFICATIONS REQUIRED!!!

Dan

I think I get your message, something like don't modify the 3 spool valve ?

Probably best at this point if I make a bucket and at least a grapple so I can use it, them decide if it's worth changing.

 

[TheOldHokie]

I think I get your message, something like don't modify the 3 spool valve ?

Probably best at this point if I make a bucket and at least a grapple so I can use it, them decide if it's worth changing.

Right on both counts

Plus, why make a grapple or a bucket when you have a SSQA loader?

Dan

 

[Paul Allwood]

Right on both counts

Plus, why make a grapple or a bucket when you have a SSQA loader?

Dan

Do you mean why not but a bucket and a grapple ?

 

[TheOldHokie]

Do you mean why not but a bucket and a grapple ?

Yes. They are standard loader attachments that will fit your SSQA loader right out of the box.

Dan