Dump wagon build

[CDN Farm Boy]

Correct me if I'm wrong, but location matters. The closer the cylinder attaches to the front of the box, the better. Lifting at the front edge of the box would need a lot less lift than lifting from the middle. Turning the cylinder and pushing from the back should or at least could, make for a more forward lift point on the box. A good thing. Course, this would also mean longer cylinder travel to achieve the same angle of dump. Seems like a longer cylinder would be easier and cheaper than building for less travel but higher total forces.
Or not.

That's exactly what rswyan was suggesting, but if my math was right, not quite that simple. At the same heights as I have now, with just reversing the mounting, due to the reduced effective angle of the cyl, would only have a net gain of about 550 lbs. Raising the bed 4" relative to the lower cyl and reversing the cyl would make a significant difference.

As for dump angle, this orientation would actually gain about 5 deg of dump with the same cyl.

Something still seems wrong with orienting the cyl this way to me. Aside from a couple people here, I've never seen one like this. Why are they not a more common design?

 

[rswyan]

That's exactly what rswyan was suggesting, but if my math was right, not quite that simple.

Without seeing exactly what you did for "math", I'd have no way of knowing.

At the same heights as I have now, with just reversing the mounting, due to the reduced effective angle of the cyl, would only have a net gain of about 550 lbs. Raising the bed 4" relative to the lower cyl and reversing the cyl would make a significant difference.

Just so we're clear here. when I say "reverse the cylinder" I'm talking about pushing the front of the deck up - not simply flipping the cylinder around on it's current attachment points.

IOW: new attachment points to push the deck up from it's front.

As for dump angle, this orientation would actually gain about 5 deg of dump with the same cyl.

Which orientation ?

Something still seems wrong with orienting the cyl this way to me. Aside from a couple people here, I've never seen one like this.

Really ?

Why are they not a more common design?

Might be more common than you're thinking ...

 

[CDN Farm Boy]

Without seeing exactly what you did for "math", I'd have no way of knowing.

I'll try to clarify...see next post. I'll have to condense my CAD drawings and hen-scratching to something more post-friendly but the results are in post #39

Just so we're clear here. when I say "reverse the cylinder" I'm talking about pushing the front of the deck up - not simply flipping the cylinder around on it's current attachment points.

IOW: new attachment points to push the deck up from it's front.

Yes, I thought I followed. 180 the cyl within the current mounts would do nothing but need longer hoses. Bed side cyl mount would be at the front of the bed but that would place the base end of the cyl at mid-point of the reach similar to Steve has in post #36.

Which orientation ?

As noted above vs my current setup. See drawings in next post

Really ?

View attachment 406166

Might be more common than you're thinking ...

Not the same orientation as I understood from your suggestion. That has both ends of the cyl at the front of the bed it is pretty much a 90 deg lift. Obviously the way to go to get the most force out of the cyl but you need a much longer cyl to do it. I'd need a 64" stroke cyl to get the same amount of dump angle that I have now from my 30" cyl. At a 90 deg lift, I could get by with a 2" or 2.5" bore cyl giving 6900 or 10800 lbs respectively of lift to get in the same effective lift area as with the 4" cyl mounted on the angle. Upside to this design is horizontal forces are eliminated but would require a TALL tower at the front of the wagon to mount the cyl, even with using a telescopic cyl.

 

[CDN Farm Boy]

As built:



As per my understanding of rswyan's (and others') suggestion:



Omitted from the drawing for clarity is that there is also 12" of rear overhang past the hinge and 21" of front overhang past the base cyl mount. Since these affect both designs equally, I left them out of the drawings. 4" bore cyl with 30" stoke running a guess of 2200 psi as that is my understanding of the factory setting of the relief valve on my tractor

 

[CDN Farm Boy]

The cold finally let up a bit and made it up to -8 today so I took the time to get some measurements and plug them into CAD to get the cyl angle. My 10 deg guess was pretty frickin close. Cad says 10.38 deg at rest. So using the link from Surplus Center forces go something like this:

Current:
10.38 deg = 4981 lbs of lift 4' from the box pivot
Lift whole thing 4": 13.39 deg = 6398 lbs of lift
Lift whole thing 6": 19.44 deg = 9201 lbs of lift - really don't want to raise it this much

If I were to reverse the mounts as rswyan suggests:
At existing height: 5.74 deg = 2765 lbs of lift 8' from the box pivot
Lift whole thing 4": 11.5 deg = 5512 lbs of lift

With factoring in the mechanical advantage of the lever of the box (if I"m calculating right), the second way would give me an extra 549 lbs of lift BUT also an extra 2216 lbs of horizontal push now trying to push the box off the front of the frame rather than the back. I'm not sure this is an improvement. Now if I were to reverse the cyl AND lift everything 4" I could gain 4626 lbs of effective lift for a total of 11024 lbs by comparison. This is obviously a big improvement but has the challenge of the cyl base mount being in the middle of the reach which is it's weakest point rather than now with it on the front frame. Anyone know how much force is required to bend a 3" pipe pushing in the middle of a 8' lenght?

If I got this right, I'm either going to weld it solid to the wagon frame at it's current height or raise it 4" and weld it solid. If that doesn't work, I'll incorporate a scissor lift once I look at the geometry a bit more.

In these calculations I made an error as to the length of the lever and the ratio between them. The second option should have had a factor of 1.8:1 not 2:1 for calculating equivalent lift. Lever length for the first (as built)option is 48" while the (my understood) proposal has a length of 86.5"

So to re-calculate the proposed layout:
5.74 deg = 2765 lbs of lift @ 1.8 lengths of the original lever (86.5 vs 48) = 4977 which is pretty much exactly what I have now. 2765 lbs of lift on a 86.5" lever is the same as the 4981 lift on the 48" lever. Please correct me if I'm wrong.

 

[Steve_Miller]

Something still seems wrong with orienting the cyl this way to me. Aside from a couple people here, I've never seen one like this. Why are they not a more common design?

Company Normand - Farm Dump Trailers

I did the same thing as these guys. I'm no engineer but it seems that you would need less push force the farther you move forward but it comes at adding cylinder length. My methology (brain says this should work) says that less force equals smaller cylinder size. I used the link someone posted here earlier to calculate forces needed. I worked out how far down I could go to the bottom cylinder mount and went from there to calculate length and cylinder size. Their pictures are not very big but you can see how the cylinders are mounted.

Steve

 

[CDN Farm Boy]

Interesting. I've only ever seen a Normand with the vertical front mount cyl.

There's no question that lifting at the front will take less force than lifting in the middle. The difference is if the design will provide the additional force or not. Within the constraints of my build, I don't have enough height to get enough effective angle to make it worth the redesign.

It probably works in yours because you planned it that way from the start. Still seems backwards to me but apparently it works

Once I figure out how to best get my lower frame rails anchored I will be able to properly evaluate if my setup actually works since it was the anchoring that was the weak link that failed. I don't even know for sure if I have enough lift or not. If then find my current setup doesn't work, I'll likely rebuild with a telescopic cyl mounted vertically at the front like a dump truck

 

[bcp]

If then find my current setup doesn't work, I'll likely rebuild with a telescopic cyl mounted vertically at the front like a dump truck

If you are buying a telescopic cylinder, get one to mount under the center of the bed. Then, by arranging latches and pivots, it can dump to either side or the rear.

Here is the first example I found:

3-Way Dump Trailer | Marvel Construction & Equipment Rental | Valparaiso, IN

Bruce

 

[CDN Farm Boy]

If you are buying a telescopic cylinder, get one to mount under the center of the bed. Then, by arranging latches and pivots, it can dump to either side or the rear.

Here is the first example I found:

3-Way Dump Trailer | Marvel Construction & Equipment Rental | Valparaiso, IN

Bruce

Those are neat, never seen one as a trailer, only as small tracked or wheeled buggies on construction sites. To use that idea, might as well start from scratch. Too much redesign for what I have now. Not to mention, too much vertical underbed height is needed for my tastes

 

[rswyan]

I'll try to clarify...see next post. I'll have to condense my CAD drawings and hen-scratching to something more post-friendly but the results are in post #39

Ok.

Yes, I thought I followed. 180 the cyl within the current mounts would do nothing but need longer hoses.

Actually just reversing it using the same mount points would reduce the force ... because the rod side of the has less surface area for the fluid (under pressure) to act on.

Bed side cyl mount would be at the front of the bed but that would place the base end of the cyl at mid-point of the reach similar to Steve has in post #36.

Correct.

As noted above vs my current setup. See drawings in next post

Ok.

Not the same orientation as I understood from your suggestion. That has both ends of the cyl at the front of the bed it is pretty much a 90 deg lift. Obviously the way to go to get the most force out of the cyl but you need a much longer cyl to do it. I'd need a 64" stroke cyl to get the same amount of dump angle that I have now from my 30" cyl.

Fab a scissor lift at the front that points rearward.

When the bed is full down, the scissor lift is already partial open.

Make the lower arms/rails for the lift somewhat longer the ones for the top (the top arms will sit "level", the bottom arms will already be angled upward)

Attach your cylinder to the hinge pin that connects the two sets of arms (or thereabouts)

Push the scissor lift open to raise, pull it closed to lower.

At a 90 deg lift, I could get by with a 2" or 2.5" bore cyl giving 6900 or 10800 lbs respectively of lift to get in the same effective lift area as with the 4" cyl mounted on the angle. Upside to this design is horizontal forces are eliminated but would require a TALL tower at the front of the wagon to mount the cyl, even with using a telescopic cyl.

I only posted the picture to illustrate the point being pushed/acted upon (the front), not necessarily the type of cylinder or it's orientation.

 

[bcp]

Actually just reversing it using the same mount points would reduce the force ... because the rod side of the has less surface area for the fluid (under pressure) to act on.

Force would be exactly the same if reversed. The fluid still has to go into the base end, not the rod end, to extend.

Bruce

 

[rswyan]

... Once I figure out how to best get my lower frame rails anchored I will be able to properly evaluate if my setup actually works since it was the anchoring that was the weak link that failed. I don't even know for sure if I have enough lift or not. If then find my current setup doesn't work, I'll likely rebuild with a telescopic cyl mounted vertically at the front like a dump truck

It will "work" ... until you really load it up ... and then you'll run short on "steam" to push it up.

The reason I say that is I have 4 x 8 cart and you have a 6 x 10 ...

I'm using a 4" cylinder @ around 2000 psi ... at a roughly similar initial angle. (think mine might be 12 degrees but I would have to check it)

When I have mine fully loaded (probably overloaded by 1000 lbs - 5K in the bed) it will barely raise ...

You have 28 sq. ft. more floor area than I do ... 60 sq. ft. vs 32 sq. ft. - that's almost double.

If you want to be able to fully utilize all that additional floor area and be able to dump a heavy load, you're going to have to get the mechanical aspects (mainly leverage, initial angle, and mechanism) correct to do it.

 

[rswyan]

Force would be exactly the same if reversed. The fluid still has to go into the base end, not the rod end, to extend.

Bruce

Good catch - my error :thumbsup:

 

[Rustyiron]

CFB, It looks like if you were to add some "long sills" as they are called on a truck dumper, right under your "lower frame", just like a dump truck, you could use this to "hang" some side plates down, then go across with a heavy (wall) pipe or sq tube…. like 4" sch.80 or 4x4/3/8 wall (remember the forces this will see will be (approx) 45* to almost 90*) so it needs to be strong on more than one axis, pipe & sq. are good for this over any "I" or angle. This would be your new & lower location to mount your cly. If I've not explained this properly, think of an older grain dump (truck). They would often have this type of set up although usually with a cylinder on each side of the (truck) frame. This would also be an option for you. These new "long sills" should also be (in my guestimation) 6" chan @ about 10.5 lbs./ft. assuming that the cyl. would be mounted at about 1/3 of the span. Also the side plates that drop down to support your X tube for the cyl. mount needs to be somewhat of a large triangle also for the above described forces back & down.

 

[CDN Farm Boy]

Yes Rusty, that makes sense if I were to use dual cyl. As it is, with a center mounted cyl, I can go any lower than the reach. But your idea could be a way to strengthen things for a centerish lower mount even with what I have now, if the geometry were in my favour

 

[thirdroc17]

Frankly, with the mechanical disadvantages of having the lift cylinder under the bed as compared to a telescopic cylinder lifting directly at the front, I'm amazed any dump box dumps!

The telescopic cylinder at the front has it's greatest lift force when the bed is down. Cylinder under the bed has it's least lifting force when the bed is down. It's just backwards. Unless of course there is some fancy linkage beyond my ability to design.

But hey, they work, and that's all that matters, eh?

 

[CDN Farm Boy]

If you want to be able to fully utilize all that additional floor area and be able to dump a heavy load, you're going to have to get the mechanical aspects (mainly leverage, initial angle, and mechanism) correct to do it.

I don't disagree with you on that. Since what I have is seemingly not going to work the best, I need to figure out exactly how to best move forward from this point. Depending on how corrective action will be taken to improve dump force, will have an affect on how I re-anchor things. If I switch to a front mount telescopic cyl, then the only horizontal force would be from gravity acting on the raised bed. I knew from the outset that I'd have more horizontal force than vertical in my design but since I had no force calculator to see just how much lift I would get from the angled cyl prior to construction, it was all just a guess if I would have enough.

With a front mount cyl, it's pretty easy to calculate the forces. I'm going to look into the specific design and forces of incorporating a scissor lift and see how it would work in my application. If I can make a scissor lift fit within my given space (12" from top of reach to bottom of bed crossers in current configuration) AND improve lift force, that's likely the way I'll go since it would reuse my existing cyl and hoses. It still seems to me that the main purpose of a scissor design is to be able to use a shorter cyl. If I have to raise the bed a few inches, I will but I'd rather not. The other thing I need to figure out is if I can make a scissor lift work with my 30" cyl. Better to figure that out now before I spark the welder back up.

 

[CDN Farm Boy]

Frankly, with the mechanical disadvantages of having the lift cylinder under the bed as compared to a telescopic cylinder lifting directly at the front, I'm amazed any dump box dumps!

The telescopic cylinder at the front has it's greatest lift force when the bed is down. Cylinder under the bed has it's least lifting force when the bed is down. It's just backwards. Unless of course there is some fancy linkage beyond my ability to design.

But hey, they work, and that's all that matters, eh?

Eh? You must have some good Canadian blood in you! :thumbsup: :laughing:

You are exactly right on the forces but with the cyl under the bed it's the most compact design and a standard cyl can be used rather than a telescopic at double the price. As someone mentioned earlier, brute force can overcome this as long as the components can take it -- which is where mine failed. I sheered off my stop blocks and was pushing it off the back of the wagon rather than lifting it.

 

[CDN Farm Boy]

CFB, It looks like if you were to add some "long sills" as they are called on a truck dumper, right under your "lower frame", just like a dump truck, you could use this to "hang" some side plates down, then go across with a heavy (wall) pipe or sq tube? like 4" sch.80 or 4x4/3/8 wall (remember the forces this will see will be (approx) 45* to almost 90*) so it needs to be strong on more than one axis, pipe & sq. are good for this over any "I" or angle. This would be your new & lower location to mount your cly. If I've not explained this properly, think of an older grain dump (truck). They would often have this type of set up although usually with a cylinder on each side of the (truck) frame. This would also be an option for you. These new "long sills" should also be (in my guestimation) 6" chan @ about 10.5 lbs./ft. assuming that the cyl. would be mounted at about 1/3 of the span. Also the side plates that drop down to support your X tube for the cyl. mount needs to be somewhat of a large triangle also for the above described forces back & down.

Rusty, I'm wondering if these "long sills" you refer to are actually the same as my "lower frame"? In the below pic, you can see that I have the 2x4 tube as main and side rails of the bed AND 2 lengths that remain horizontal with the wagon frame -- these are what I was calling my "lower frame". If I'm interpreting you right, I'd simply be doubling these up.

View attachment 404595

 

[aczlan]

That if you took out the center portion of your reach at the end where the base of the cylinder is and replaced it with either:
1. A piece on each side moved outboard far enough that the cylinder can fit inbetween going back to the intersection of the reach and the C channels that come up from the axle.
2. A piece on each side moved outboard 6" that goes straight back to the C channels that go from the axle to the reach.
Here is a drawing showing the current setup and the above options.

That would let you move the base of the cylinder down enough that it can have more lifting force and would also give you a place to tie some reinforcement into if desired.

Aaron Z