[formum]

Bob...I bet you used to use slide rules? I'm WAY too young for that.

The photo below shows why I went to an under the arm position for the bucket dump cylinders. I have seen it both ways...but my inital approach was on top.

This ford tractor is pretty **** close to the Jake I want to put my loader on.

 

[TUDOR]

Bob...I bet you used to use slide rules? I'm WAY too young for that.

The photo below shows why I went to an under the arm position for the bucket dump cylinders. I have seen it both ways...but my inital approach was on top.

This ford tractor is pretty **** close to the Jake I want to put my loader on.


View attachment 203389

Yup! Friden calculator, too! We got the modern stuff, the class before us used an abacus. I carried my 6" slipstick in my shirt pocket for several years. Back then, my eyes were good enough to read 4 significant digits. Now, it's more like 2.5.

As a millwright, I gained an appreciation for having the equipment that I was working on accessible by overhead crane. As an old man, I appreciate not having to squat to work on equipment even more. Nothing wrong with slinging that bucket cylinder underneath, but my knees and back would protest if I had to change it out while it was fully down.

Well, I found out what was bothering me, on the line N-A-O, my numbers are , N-A = 30" and A-O = 22". Both my tractor and loader are a little bigger than yours and I was noticing the different ratios. My loader also has self levelling links so quite a few of my numbers won't translate for yours.

I also noticed that your lift cylinder c-c is a little shorter than mine.

 

[TUDOR]

Solve the hydraulics problem first. That will give you the dimensions and shape. Force vector anaylsis comes when all of the dimensions are finalized and before fabrication commences so that each component can be sized for the required strength.

Or, build it with way overstrength components without the FBD like the rest of us do. (Although, I do like the numbers that you produced for us. Thanks! I'm going to save that info for future reference!)

The bucket cylinder on the Ford has one end in the dirt. Not really the best situation for chromed surfaces.

 

[formum]

Bob, that is a good point about the chrome in the dirt. Even if you flipped the clylinder around you still get the lines in an area that will get a lot of action from falling debris. With that in mind I will try to relocate the bucket cylinder up to the top...shouldn't be an issue.

I moved my arm cyclinder down 5" on the main uprights and it gave me a significant amount of more load capacity with a pressure relief set at 1500psi and 1.25" rods. I "should" be able to lift around 700lbs in the bucket. I'd have to figure out if I could fit enough "stuff" in the bucket to get to 700lbs. I am sure i could get there by trying to move around something too large.

I am also thinking about not having the mower mounted so I can move the main riser back almost even with the steering wheel. Get more weight back.

 

[TUDOR]

I moved my arm cyclinder down 5" on the main uprights and it gave me a significant amount of more load capacity with a pressure relief set at 1500psi and 1.25" rods. I "should" be able to lift around 700lbs in the bucket. I'd have to figure out if I could fit enough "stuff" in the bucket to get to 700lbs. I am sure i could get there by trying to move around something too large.

I am also thinking about not having the mower mounted so I can move the main riser back almost even with the steering wheel. Get more weight back.

You also need to figure the payload capability at the top of the stroke. If you lose too much, that's not a good thing for the mid-level where it spends most of its time. Somewhere between 14" and 19" is the best lifting advantage for your loader. You're unlikely to ever use it, but it's nice to have the reserve. Don't forget, you're only dealing with one arm. The FEL has 2 arms.

"if I could fit enough "stuff" in the bucket to get to 700lbs". How about the butt end of a 2200 lb log? Or, what can I rap a chain around and hook to the bucket? This one is why you also want lift capability at the top of the stroke. Just because the bucket is way up there doesn't mean the payload is too. I lifted a 29'x12' carport roof, along with with its temporary supports, 1" at the top of the stroke so that I could install the new support posts. That's over 1000 lb at the top of the lift, but the supports were only 1" off the concrete.

Moving the posts back is not so much about getting weight back there (the loader and subframe should be close to balanced on the front axle anyway) as it is to shorten the lever from front axle to payload to get the most benefit out of the ballast at the rear of the tractor. Leave enough room to get on and off the tractor quickly with the controls in the way.

Ballasting is another topic altogether. The necessary info will be generated with the final FBD. This section is about loader capability. What the capacity will be is something else.

 

[formum]

You also need to figure the payload capability at the top of the stroke. If you lose too much, that's not a good thing for the mid-level where it spends most of its time. Somewhere between 14" and 19" is the best lifting advantage for your loader. You're unlikely to ever use it, but it's nice to have the reserve. Don't forget, you're only dealing with one arm. The FEL has 2 arms.

"if I could fit enough "stuff" in the bucket to get to 700lbs". How about the butt end of a 2200 lb log? Or, what can I rap a chain around and hook to the bucket? This one is why you also want lift capability at the top of the stroke. Just because the bucket is way up there doesn't mean the payload is too. I lifted a 29'x12' carport roof, along with with its temporary supports, 1" at the top of the stroke so that I could install the new support posts. That's over 1000 lb at the top of the lift, but the supports were only 1" off the concrete.

Moving the posts back is not so much about getting weight back there (the loader and subframe should be close to balanced on the front axle anyway) as it is to shorten the lever from front axle to payload to get the most benefit out of the ballast at the rear of the tractor. Leave enough room to get on and off the tractor quickly with the controls in the way.

Ballasting is another topic altogether. The necessary info will be generated with the final FBD. This section is about loader capability. What the capacity will be is something else.

Bob, you make a good point. You don't know how much force it will take to move a large stone or a stump. Safety factor, safety factor safety factor.

 

[formum]

So getting the dump cyclinder (per Bob's good observation) was a little tricky. I didn't seem to be able to postion it correctly where I had enough "tilt back" when I was 3" below grade but enough extension when fully extended to dump at higer elavations. I think I found a happy medium here.

Thoughts? Concern? Praise? Anyone besides Bob have an opinion? You know what they say about opinions? :fing32:

I would like to nail down this geometry and the cylinders so I can figure out if I have clearance to make this geometry work in 3D.

Also need to do more FBD to see if I have no hope of keeping the back wheels on the ground.

:thanku:

 

[formum]

Maybe I need to figureout an autoleveling system too...

 

[TUDOR]

Gotta throw a monkey wrench at you, man. Have you considered a longer cylinder for the bucket? The ones on my GT are 1.5X13, and on my SCUT they're 1.5X13.5.

Something to consider for getting the dump angle correct is to work with the pin locations on the bucket. The lower pin hole for the arm can be moved backward a couple of inches, as can the top pin hole for the cylinder which can also be moved up and down. Well, maybe not down much, but it can be moved up as much as 5" if necessary.

Here's a simple FBD for FELs. Dx from front axle to center of payload mass times the mass minus Dx from front axle to rear axle times the axle load. If the answer is negative, the wheels stay on the ground. If it's positive, you need more counter weight. Payload times 2 plus empty load on the front axle equals the load on the axle.

It's not precise, but it works, and with a bit of safety factor as well. We're moving mole hills, not mountains.

Decent hydraulic geometry with a pair of 2x18 cylinders at 1500 psi will lift over 2000 lb at the ends of the arms. Very few GTs can carry sufficient counterweight, without exceeding rear axle static load capacity, to make that happen. None can do it and remain anywhere near the load limits of the front tires.

Max load for 18x9.5-8 6 ply tires at 90 psi is less than 1000 lb. Anything over a 750 lb payload will exceed the tire's rating.

Good hydraulic geometry means the system doesn't have to work hard and build heat in the process. On these tractors, it doesn't have much to do with how much they will lift. There are too many other factors which limit their lifting capacity.

 

[formum]

So...taking Bob's advice I went with 2x18 on the arms and NOW 2x18 on the bucket dump. That extra stroke...and moving the cyclinder pivot up the back of the bucket also helped the geometry.

Getting closer? I still think I am sticking too far out from the front of the tractor.

 

[formum]

Worked out the mechanical self leveling system for the bucket. I watched this vidoe:
http://www.youtube.com/watch?v=4nTMXu5Q5fA

and stole the geometry from it. Seems to work pretty well...

 

[formum]

With the auto leveling...and the bucket as far away from the tractor as is possible by the current setup I get the resultant forces on the front and back tires with a 300lbs payload:

661.125lbs pushing down on the front tires (2ply tires won't cut it)
361.165lbs lifting the back tires up

1365lbs. (total) acting on both hydraulic cyclinders for the arms

328lbs (total) acting on both the hydralic cyclinders for the bucket dump

This calculation doesn't assume the weight of the tractor or the FEL...but once I finalize the design (lengths and shapes used) I can input those forces too.

Anyone know the weight of a Jacobsen GT16H?

 

[formum]

I am also looking at this hydraulic control valve

https://www.surpluscenter.com/item.asp?item=9-7862&catname=hydraulic

8gpm
two spool
open center converatble to beyond power

 

[TUDOR]

I am also looking at this hydraulic control valve

https://www.surpluscenter.com/item.asp?item=9-7862&catname=hydraulic

8gpm
two spool
open center converatble to beyond power

Most loaders have a float position on the spool for the arms. The 7 gpm valve just above that one is so equipped.

Here's another equal to the one you posted, only with a float position and a lower relief capability.

http://baileynet.com/index.php?dnfwd=1&page=ProductDetails&line=CVLT&baileyno=220-131

And another that is joystick controlled and also with regeneration on the second spool.

http://baileynet.com/index.php?dnfwd=1&page=ProductDetails&line=CVLT&baileyno=220-133

For the bucket cylinders, 18" is way too much, 12" or 14" would be my recommendation.

That Bolens bucket center is about 40" out front of the axle. The bucket on mine is a 35% scaled up version in all dimensions and is about 34" to bucket center. I can't back it up any more and keep the hood installed.

Take a look at the levelling linkages on the Suburban. They're a little simpler and the same style as on mine.

 

[TooManyToyz]

Here's the self leveling system on my loader:

 

[formum]

That self leveling system looks much simpler...I like it!

 

[TUDOR]

Here's the self leveling system on my loader:

TooManyToyz, I see a little bit of bending in that levelling link. I straightened mine out so many times they had stress cracks. Eventually, the left one broke at the front bushing while under load (of course). It whipped back to its travel limit and rebounded back into its normal orientation in the blink of an eye.

Both 3/4"pipe leveller links were replaced with 1 1/4 X 1/8 wall square tube in short order after that. No more bending since.

 

[TooManyToyz]

Not to steal the thread, but that's one of the things being replaced during the rebuild. I should probably update my thread on that tractor.

 

[formum]

Bob, that is a good idea to use 1.25 square tubing instead of the round.

 

[formum]

So with the aquired wisdom of a few other threads on this site...let me show my preliminary schematic for the hydraulic system. Definetly looking for input here.