Limiting Cylinder Stroke on Log Splitter

[D Chaplin]

I'm going to start selling firewood next season and I'm planning a new design for my next log splitter build. I did a short video of the last one I built and posted it on Youtube here: . I'm fascinated with some of the new machines from Eastonmade and Timberwolf but I love fabrication and enjoy building these things. Anyhow this last one was an awesome learning experience and looking to build an even faster machine this time. Something with a 28 gpm pump and a 4.5" cylinder with a 3" bore. I'm trying to get cycle times down to 4-5 secs and planning to build a 7 way box wedge and a 6 way wedge also

I cut all my firewood at 16" but the cylinders are all 24" which means you waste a lot of time with unnecessary stroke. I'm trying to come up with a solution to limit the stroke to 18" without permanently shortening the stroke. There are some videos on YouTube where guys have machined bushings that went inside the cylinder and limited the stroke with a 3-4" bushing. However, I want something less permanent in case I ever got into boiler wood or something other than just fireplace/bundle wood.

I'm wondering if you drilled 2-4 holes in the beam and bolted a plate across that would catch your push block on the return stroke if that would quickly build pressure enough to trip the autocycle valve or not. The concern of course is the speed at which this would retract because a properly plumbed cylinder with a diverter valve would move at approximately 12-13" per second in the return stroke. Combine that with the sudden stop (over and over) and I can see that being like a battering ram every return stroke.

But then again I also wonder if that would be any different than the cylinder fully retracting and bottoming out every stroke because that valve is tripped every cycle by the sudden spike in pressure from the cylinder reaching the end.

I've never seen anything like this on any commercial splitters so I'm guessing there is probably a reason for it but I wanted to ask the larger audience.

 

[SimonHS]

Found this. Not sure if it would suit your splitter, but the idea is sound. And the splitter doesn't have to be permanently modified.



Maybe you could turn the idea on its head? Put the return valve on a sliding bar that you could move outwards and lock at different lengths?

 

[jblnut]

You could fab up some simple cylinder stops like these. I use them on tillage equipment to control how deep the implements go. They’re too small for your application but it’s the idea …..
https://www.shoupparts.com/9130-stroke-control-kit/
Or a single point depth control valve from a John Deere field cultivator. You mount the valve stationary and an adjustable plate that moves with the cylinder pushes the button and closes the valve. It automatically resets when you extend the cylinder again. I can take some pics of one on my cultivator if you’d like.
https://shop.deere.com/us/product/AN241790:-Single-Point-Depth-Control-Valve/p/AN241790

 

[jblnut]

Here is a picture of a single point depth control valve mounted on something. This has the potential to work exactly like you want it to …..

 

[sean donato]

They sell stop collars to limit the return stroke. Cheap and effective. The return should kick out around 500-700 psi anyway, so not going to hurt anything. Tad more money, but get a custom cylinder made of your super worried about stroke length. Is not really difficult for a decent hydro shop to shorten one.

Box wedges are very, very, messy splitters. I'd be going multi wedge before a box wedge.

 

[dave ensign]

I often wish my return time was a bit faster but 12/13 inches a second would bring safety into question for me. That said I have two wood blocks that fit on my pusher to shorten the stroke for short rounds.

 

[D Chaplin]

I often wish my return time was a bit faster but 12/13 inches a second would bring safety into question for me. That said I have two wood blocks that fit on my pusher to shorten the stroke for short rounds.

If you watch videos of some of the Eastonmade (24D for example) or some Timberwolf you'll see approximately what that would look like. It would be quick but still not as fast as a kinetic splitter like a Supersplit for example.

 

[D Chaplin]

They sell stop collars to limit the return stroke. Cheap and effective. The return should kick out around 500-700 psi anyway, so not going to hurt anything. Tad more money, but get a custom cylinder made of your super worried about stroke length. Is not really difficult for a decent hydro shop to shorten one.

Box wedges are very, very, messy splitters. I'd be going multi wedge before a box wedge.

I agree, but the speed and consistency for someone planning to sell wood to me makes up for the mess. I have a 4 way and it can accumulate quite the pile of trash. I would imagine that the box wedge will triple that. However we have places we can use it for a while anyhow. Raised garden bed filler, chicken run scratch (then compost), and other places. Eventually we'll have to burn some I'm sure

 

[Pjohnson]

If you put your numbers in a calculator the difference between 18 and 24 inch stroke is about 1.5 sec not a huge time saver. One thing i see eastonmade does is run his splitters at higher pressure like 36 or 3800. He can then get more force with a smaller cylinder and have faster cycle time. I have no idea where he gets the pump i dont see many components rated for that pressure.

 

[turnkey4099]

They sell stop collars to limit the return stroke. Cheap and effective. The return should kick out around 500-700 psi anyway, so not going to hurt anything. Tad more money, but get a custom cylinder made of your super worried about stroke length. Is not really difficult for a decent hydro shop to shorten one.

Box wedges are very, very, messy splitters. I'd be going multi wedge before a box wedge.

Stop collars is what I used on my first splitter. Unfortunately it wss a used cylinder and used valve. Apparently there was no kick out on the valve and iwas breaking grade 8 bolts.

 

[husky455rancher]

I tried those stroke limiters like in the link in my Wolfe ridge. they worked a few times. Then outta no where one exploded. So I stopped using them immediately. I do wish my return speed was quicker.

 

[Yarz]

Eastonmade has made an adjustable stop. Check out this video, about a minute in, and then a more detailed view at 8:15:

 

[husky455rancher]

Eastonmade has made an adjustable stop. Check out this video, about a minute in, and then a more detailed view at 8:15:

That’s brilliant! Don’t think I got that much room under my cylinder but I’m gonna check it out

 

[dave ensign]

I would not own a kinetic splitter

If you watch videos of some of the Eastonmade (24D for example) or some Timberwolf you'll see approximately what that would look like. It would be quick but still not as fast as a kinetic splitter like a Supersplit for example.

.

 

[sean donato]

I agree, but the speed and consistency for someone planning to sell wood to me makes up for the mess. I have a 4 way and it can accumulate quite the pile of trash. I would imagine that the box wedge will triple that. However we have places we can use it for a while anyhow. Raised garden bed filler, chicken run scratch (then compost), and other places. Eventually we'll have to burn some I'm sure

I did a lot of work in a large wood processor a few years back. Live deck, one guy feeding it logs, one operating and another filling bags/moving processed wood. They started with a 4 way wedge, went to a box wedge and tossed that and went to a 6 way wedge. The box wedge wasted a lot of wood, and made tons of trash. Besides the electrical issues the engine was having it was the owners biggest complaint about it.

If you put your numbers in a calculator the difference between 18 and 24 inch stroke is about 1.5 sec not a huge time saver. One thing i see eastonmade does is run his splitters at higher pressure like 36 or 3800. He can then get more force with a smaller cylinder and have faster cycle time. I have no idea where he gets the pump i dont see many components rated for that pressure.

It's likely all custom made, while 4k psi systems are pretty common in heavy equipment these days, 3k psi systems dominate just about every other market.
Cycle time also doesn't have much to do with pressure ratings, flow is more important, the steep pressure rise only occurs when the cylinder hit the wood, pressure rises to maintain the flow rate untill you hit relief pressure.
Another thing most over look in homebuilt splitters is the rod size. Most purpose built commercial splitters have very large rods, this effectively makes the cylinder much smaller on the return stroke, making for fast retraction times. Important in an processor,less important when you're dealing with a typical splitter where the operator stand right in front of the cylinder.
That same processor had a 6inch cylinder, 4.5 inch rod, 24 inch stroke. Now it was backed by a 120hp deere engine and had plenty of pump behind the cylinder was fast to extend, but flew back in. No one bothered with trying to adjust its length of stroke.

 

[composter]

About that trash: we generate a lot of it too, but we put in recycle containers to dry, box it and sell it as kindling for $5 box.

 

[c5rulz]

I've got a stroke limiter on my splitter. Cylinder is a 30" but the stop plate can be set between 19" limit minimum with adjustments every two inches. I normally run it at 21". The splitter has auto cycle valves along with a dump valve to speed up return and abate heat.

 

[Kevin in Ohio]

Like the above Post, I use a steel stop on the slide.

I have a 5 inch cylinder/2 12" rod and used a Box on box design on mine so I did a stop in under the beam. Keeps it simple. I have a 30 inch stroke and normal stuff is cut 22 - 24 inches. I wanted the capability to quick change for any stuff that was cut a little long. I'm running an autocycle valve as well.

Solid stop and it can be changed in seconds.

Here it is half slid in.

Be aware if you up the GPM it may start increasing your fluid temps. I used all long sweep elbows and straight hoses like you did. Also have a bypass valve and a 30 gallon holding tank.