DHT splitter modified

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Flow controls only work in one direction. Meaning you might be able to slow the cyl down for the up stroke, but going back down will be just as fast as ever. Using a flow control might not be your best or cheapest option. Brazing up the fitting and then redrilling with about a 1/8-3/32 hole for oil flow is cheap and effective.
one way needle valves only work in one direction and free flow in the other direction... two way needle valves work in both directions Parker makes both
 
one way needle valves only work in one direction and free flow in the other direction... two way needle valves work in both directions Parker makes both
Yes they do make flow controls that work in both directions, but brazing up the fitting and drilling a small orfice is still cheaper. I am not sure on this so somebody can check on it, but using a single directional flow control with a hydraulic cylinder, the flow control would need to be mounted before the control valve because of the difference of flow entering the piston end of the cyl or the rod end of cyl. Might not be possible if you are using a multispool valve. Not sure how well a bidirection valve would work if only one was used and placed on the piston side of the hydraulic cylinder, if used this way, you could control the return speed of cyl, but the extend speed would still be slower than retraction. Fluid pushing in the rod end on cyl retraction will cause a excess of oil flowing out of the piston end of cyl. Using two seperate single directional flow controls on the A and B ports of cylinder would enable you to more closely regulate the speed of the cyl so that more flow can return on one side of the seperate ends of the cyl., depending on which way the oil is flowing at the time. One flow control would have to allow more oil to flow than the other control to keep the cyl speed equal. Simply placing a bi-directional flow control in the cyl circuit will slow the cyl speed, but the retract speed would still be faster than the extend speed. Bi direction flow controls can cost less than $20 and the price goes up from there, then add on the cost of the other fitting needed for the plumbing. Brazing a fitting shut and then drilling a hole for oil passage might not be as easy to adjust the oil flow, but the cost is simply the cost of a brazing rod and the time it takes to fine tune the orfice size.
 
Yes they do make flow controls that work in both directions, but brazing up the fitting and drilling a small orfice is still cheaper. I am not sure on this so somebody can check on it, but using a single directional flow control with a hydraulic cylinder, the flow control would need to be mounted before the control valve because of the difference of flow entering the piston end of the cyl or the rod end of cyl. Might not be possible if you are using a multispool valve. Not sure how well a bidirection valve would work if only one was used and placed on the piston side of the hydraulic cylinder, if used this way, you could control the return speed of cyl, but the extend speed would still be slower than retraction. Fluid pushing in the rod end on cyl retraction will cause a excess of oil flowing out of the piston end of cyl. Using two seperate single directional flow controls on the A and B ports of cylinder would enable you to more closely regulate the speed of the cyl so that more flow can return on one side of the seperate ends of the cyl., depending on which way the oil is flowing at the time. One flow control would have to allow more oil to flow than the other control to keep the cyl speed equal. Simply placing a bi-directional flow control in the cyl circuit will slow the cyl speed, but the retract speed would still be faster than the extend speed. Bi direction flow controls can cost less than $20 and the price goes up from there, then add on the cost of the other fitting needed for the plumbing. Brazing a fitting shut and then drilling a hole for oil passage might not be as easy to adjust the oil flow, but the cost is simply the cost of a brazing rod and the time it takes to fine tune the orfice size.
I use only one flow control on my log lift...as you stated the retract (down) speed is faster then the extend (up) speed... no real difference for cylinders with smallish rods (around 1/3 the size of the cylinder) my lift cylinder is 2.5" bore 1.375" rod. and the difference in speed is minimal
if it were used for a cylinder with a rod close to bore size then the difference would be dramatic.

guess it would depend on your specific situation/components but for my personal setup it works fine
 
I use only one flow control on my log lift...as you stated the retract (down) speed is faster then the extend (up) speed... no real difference for cylinders with smallish rods (around 1/3 the size of the cylinder) my lift cylinder is 2.5" bore 1.375" rod. and the difference in speed is minimal
if it were used for a cylinder with a rod close to bore size then the difference would be dramatic.

guess it would depend on your specific situation/components but for my personal setup it works fine


now that im thinking about it, I do remember questioning this when I built the splitter, and I came to the conclusion then if the flow control is plumbed into the rod side of the cylinder (retract port), it doesn't make a difference...speed will be the same...when extending the fluid entering the cylinder is controlled by the fluid exiting the rod side, and when retracting the fluid entering the rod side is controlled at the same speed as when it exited during the extending of the cylinder.

if it were plumbed into the extend port then there would be a difference in speed
 
Makes sense if plumbed on rod side. Same flow in or out so speed should be constant. I think even if speed was faster on retract, as long as you had the speed correct for lift and the logs didnt launch, then down speed should be manageable. I normally use flow controls on motors and the control is plumbed before the control valve. Equal speed in both directions. Of course there are 101 different ways to do anything.
 
So my flow control valve is doing a great job on the push side of the operation and nothing on the retract side which is where I needed to get a two way control valve instead of a one way. Mistake on my part. I'm new. So I disconnected the retract side of the spool valve and capped it. Then the weight of the table pushes cylinder back slowly. Is this a long term solution or am I better off adding second control valve to control the down operation of log lift as well? Well that hurt the cylinder running in a one way operation? Thank you for all the input.


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I have the other table on my 27 that i got in December. While I love the splitter over many other brands boy do I hate that table. No matter how hard I tighten all the bolts it inevitably loosens up a little and tilts down just enough to throw the wood on the ground. I've also had to move at lightening speed to keep a large split or piece of log from vibrating off and falling on the motor. It looks like the new version fixes that by be larger and by not having a curve to it.

I have a 27 ton also with the factory log table and this is what worked for me. The nuts never loosened on me and I didn't like the curve either until I drilled holes about an inch back from the original holes on the bottom of the table where the braces go and I'm really happy with it. I split alone and stack into a wheelbarrow directly so I often have larger splits hanging out on the table with the engine running and they no longer vibrate off with the original table tilted up.
 
I want to go back to the beam deflection for a minute. With a no load lift causing that much deflection (Yes, I am taking into consideration them problem you have with the control of speed) - if you drop a 250 log on that dude - even at a low speed lift - it appears that you may turn that beam into a pretzel.

A quick test would be to simply raise the lift a few inches off of the ground and then go stand and even bounce on the lift. See what kind of deflection you are going to have on the beam. After all this work I would hate to see you have a catastrophic beam failure.
 
I want to go back to the beam deflection for a minute. With a no load lift causing that much deflection (Yes, I am taking into consideration them problem you have with the control of speed) - if you drop a 250 log on that dude - even at a low speed lift - it appears that you may turn that beam into a pretzel.

A quick test would be to simply raise the lift a few inches off of the ground and then go stand and even bounce on the lift. See what kind of deflection you are going to have on the beam. After all this work I would hate to see you have a catastrophic beam failure.
I don't think thats beam deflection as much as it's the slop of a convertable splitter. I'd think a little boxing in of the opposite side tying the top and bottom flanges together would take any chance of "wringing" the "I" beam away. And once the beam is welded solid and becomes part of the chassis alot of that flopping around will go away.
 
I don't think thats beam deflection as much as it's the slop of a convertable splitter. I'd think a little boxing in of the opposite side tying the top and bottom flanges together would take any chance of "wringing" the "I" beam away. And once the beam is welded solid and becomes part of the chassis alot of that flopping around will go away.
I agree. The convertible splitter was never designed to have to worry about side tension. It will be remedied soon once the splitter beam is attached to chassis with something stronger than a slip pin.


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This holds up and down. Worthless for side to side. That's the problem with a rookie trying to modify a factory built horizontal/vertical. Haha.

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I have to weld some more supports in and work on some plumbing but I could not wait to try it.


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