Building a Wood Splitter

[WayneShaw]

I have a 753 Bobcat, and want to make a splitter attachment. I have the beam and plate steel. My questions are: 1) I'm going to use a 4" bore, 24" stroke cylinder, what type fittings on the cylinder should I look for? NPT? 2) What size/type control valve is used most often? 3) What size lines are used most often? I can match the quick-disconnects I'm sure. The sizes of the hoses and control valve is what I'm most concerned with. Thanks! I'm looking forward to no more splitting maul powered by me!

 

[Tazza]

Being run off the aux line, i would want to use 1/2" to 3/4" as for the fottings, that really doesn't matter one bit. As long as they all match up.
Your machine will have a flow of about 16GPM if its not hi flow. I'm sure any good hydraulic shop can tell you what hose and control should be used. As for the control, you want open centre, not closed. This will allow the fluid to flow around when you let go of the control rather than making it flow over the relief of the machine generating load and more heat.

 

[TriHonu]

Are you building the splitter to be operated from inside the loader or outside the loader with a hand controlled valve?
If you are going to operate it while standing outside the loader, then Tazza is right on about using an open center valve. This will allow you to turn on the auxiliary hydraulics (with the trigger switch) which will provide a constant flow of oil from one coupler, through the open center valve and back into the other coupler.
When you operate the open center valve to advance or retract the cylinder, the valve will divert the oil into one end of the cylinder or the other. When you release the valve the oil will again flow back into the loader.
You also want a valve that does not have detents and will spring back to closed if you let loose of the lever.
If you are going to build the splitter with the cylinder and wedge on the ground side of the beam, and plan to operate it from within the loader, you don't need a valve. You will connect the cylinder to the auxiliary lines and use the thumb switch to open and close the cylinder.

 

[TriHonu]

Are you building the splitter to be operated from inside the loader or outside the loader with a hand controlled valve?
If you are going to operate it while standing outside the loader, then Tazza is right on about using an open center valve. This will allow you to turn on the auxiliary hydraulics (with the trigger switch) which will provide a constant flow of oil from one coupler, through the open center valve and back into the other coupler.
When you operate the open center valve to advance or retract the cylinder, the valve will divert the oil into one end of the cylinder or the other. When you release the valve the oil will again flow back into the loader.
You also want a valve that does not have detents and will spring back to closed if you let loose of the lever.
If you are going to build the splitter with the cylinder and wedge on the ground side of the beam, and plan to operate it from within the loader, you don't need a valve. You will connect the cylinder to the auxiliary lines and use the thumb switch to open and close the cylinder.

You should use 3/4" inside diameter (id) hoses or larger from the loader to the open center valve and back to the loader.
On systems operating at 2000-3500 psi you don't want to the fluid speed to exceed 20 feet per second. This equates to a minimum of 9/16" id for a system with 15 gal/min. This is to minimize heat build-up in the oil due to friction.
Bobcat plumbs their attachments that need continuous flow (snow blowers, planers, mowers, augers, backhoes, etc) with 3/4" id hoses. Attachments that use the hydraulics intermittently (grapples, 4in1 buckets, etc) tend to be plumbed with 1/2" id hoses since heat build-up is not a major design consideration. I have seen 4in1 buckets and snow plows plumbed with 1/4" id lines to restrict hydraulic flow making the attachment more controllable.
At 15 gal/min a 4x24" cylinder should fully extend in just over 5 seconds. Retraction will be faster since less volume is required (cylinder rod takes up volume).

 

[jerry]

If you do install a valve definitely get one with a detent release on the return stroke, all commercial splitters have them and northern tool sells them. After 30 years I finally converted my splitter so it returns when ever the lever is released, saves a lot of time,should have done it years ago.

 

[WayneShaw]

If you do install a valve definitely get one with a detent release on the return stroke, all commercial splitters have them and northern tool sells them. After 30 years I finally converted my splitter so it returns when ever the lever is released, saves a lot of time,should have done it years ago.

Thank you all for your help. I should have been more clear on my intent. My plan is to operate the splitter at the attachment, not in the seat. So, I gather this: Use 3/4" lines, no problem. Get an "open center" valve so the fluid flows through the valve. I have heard of the detent release valves. Sounds like it would save time b y not having to stand there and hole the lever while the cylinder retracts. I would certainly control the forward motion manually, but being able to just hit the lever to return and go about clearing the wood sounds great. So far, here are the details I plan on doing, aside from the hydraulics: Wedge will be cylinder mounted. That way, I plan on welding "side panels" to hold and catch the split wood. Having the wedge fixed on the end means you have to pick all the pieces off the ground. I'm over 50, and want to limit as much work as I can! I have a piece of "boiler plate" to use as the backing mount, and will weld the bean to it with gussett pieces for rigidity. What I've been thinking on, is whether to make some sort of end "stand"? Again, I plan on welding the beam high on the backing plate to keep it high at a nice working height. But the beam will be dangling out there with no support. I've seen pics where people just rest the end on some cut pieces of fire wood, which is fine I suppose. But, I still wonder of something better could be done. Thanks again folks! Any additional thoughts are certainly welcome.

 

[jerry]

Wayne with the wedge on the ram you will have to throw all of the split wood which will involve reaching over the ram as it is retracting. With the wedge on the end of the beam the split wood falls off and as it piles up the splitter pushes it further. I have two with the wedge on the end of the beam and put small tables on each side of the beam so the split pieces lie there and if they need resplitting you can position them as the ram retracts. the tables are nothing fancy just a couple angles welded on with plywood on top maybe 12 by 20 or so. If you go to Arboristsite.com they have a section on just firewood and splitters. There are a lot of different ideas on this but I plan to do as you are and convert a splitter to mount on the Bobcat.

 

[WayneShaw]

Wayne with the wedge on the ram you will have to throw all of the split wood which will involve reaching over the ram as it is retracting. With the wedge on the end of the beam the split wood falls off and as it piles up the splitter pushes it further. I have two with the wedge on the end of the beam and put small tables on each side of the beam so the split pieces lie there and if they need resplitting you can position them as the ram retracts. the tables are nothing fancy just a couple angles welded on with plywood on top maybe 12 by 20 or so. If you go to Arboristsite.com they have a section on just firewood and splitters. There are a lot of different ideas on this but I plan to do as you are and convert a splitter to mount on the Bobcat.

Jerry, It seems to be about 50-50, whether the splitter is in the ram or beam. I've looked at every website around, and still it seems to be a preference thing. I think I'll still go with the ram splitter. I did look into a control valve, and found this that appears to be what was talked about: http://www.northerntool.com/webapp/...oduct_6970_200311695_200311695&issearch=20113
Open center, 3/4" ports, detents, etc. A typical 24" stroke, 4" bore and 2" ram seems to be the norm. They are easy to come by, Tractor Supply carries those. Quick disconnects and some hoses, and I should be good to go. Thanks again for all the help. I'll post some pics when I get it done.

 

[WayneShaw]

Jerry, It seems to be about 50-50, whether the splitter is in the ram or beam. I've looked at every website around, and still it seems to be a preference thing. I think I'll still go with the ram splitter. I did look into a control valve, and found this that appears to be what was talked about: http://www.northerntool.com/webapp/wcs/stores/servlet/product_6970_200311695_200311695&issearch=20113
Open center, 3/4" ports, detents, etc. A typical 24" stroke, 4" bore and 2" ram seems to be the norm. They are easy to come by, Tractor Supply carries those. Quick disconnects and some hoses, and I should be good to go. Thanks again for all the help. I'll post some pics when I get it done.

Oh, and I forgot to mention. By making the wedge ram mounted, I should be able to stand this on it end, ans split vertically if I have pieces too heavy to lift. I could roll them onto the stop and split them that way.

 

[skidsteer.ca]

Oh, and I forgot to mention. By making the wedge ram mounted, I should be able to stand this on it end, ans split vertically if I have pieces too heavy to lift. I could roll them onto the stop and split them that way.

I have the ram wedge variety and like it well. Rarely use it vertical, but my wood is not that big, but nice to have the option. I vote for the return detent, saves time.
You will need a catcher on each side of the beam. I also added a table on my side to hold the big haves while I quarter the other half. You will have to unload this style manually, but if you quarter wood it is vary quick to give it the 1/2 turn and not have to reposition it.
I made a stand to hold the end of mine up to working height and allows me to flip it into the vertical position without getting back into the loader. Only downside is it is only slightly heavier on the loader end then the far end of the unit and I have tipped it over while trying to pick the splitter up with the loader and bent the valve handle and nipple holding it to the cylinder. I now tilt the beam to the ground b4 I unhook it from the machine.
I think you will find 4" piston has plenty of power. ( I can shear a 6" ash cross grain and only get to 1500 psi, most skids have 2500 to 3000 psi), I have wondered about having a 3" to speed it up, but depends how tough your wood is. I run my loader on high flow at about 2000 rpm, which give me about 16 gpm. Pretty zippy but about right. Also rarely do I fully stroke the cylinder in ash or poplar, but if you wood has a stringy grain, it may be different.
The only thing I wish is I had a 30 or 36" cylinder, as our 8' truck load length are really 100" and I can't quite fit a length cut into 4 pieces (unless I do it just perfect) even though my stove will take 36" wood.
The valve you linked to is a open center "motor" spool valve. it is designed to let a motor free spool (spin) when you move the handle to the center and when used with a cylinder the cylinder could move from gravity it the verticle position.
The link below would be a better match other then the 2750 psi max relief setting, with skidsteer pressures exceeding 3400 psi, you may to check into a higher psi rated valve.
http://www.northerntool.com/webapp/wcs/stores/servlet/product_6970_472_472
Ken

 

[WayneShaw]

I have the ram wedge variety and like it well. Rarely use it vertical, but my wood is not that big, but nice to have the option. I vote for the return detent, saves time.
You will need a catcher on each side of the beam. I also added a table on my side to hold the big haves while I quarter the other half. You will have to unload this style manually, but if you quarter wood it is vary quick to give it the 1/2 turn and not have to reposition it.
I made a stand to hold the end of mine up to working height and allows me to flip it into the vertical position without getting back into the loader. Only downside is it is only slightly heavier on the loader end then the far end of the unit and I have tipped it over while trying to pick the splitter up with the loader and bent the valve handle and nipple holding it to the cylinder. I now tilt the beam to the ground b4 I unhook it from the machine.
I think you will find 4" piston has plenty of power. ( I can shear a 6" ash cross grain and only get to 1500 psi, most skids have 2500 to 3000 psi), I have wondered about having a 3" to speed it up, but depends how tough your wood is. I run my loader on high flow at about 2000 rpm, which give me about 16 gpm. Pretty zippy but about right. Also rarely do I fully stroke the cylinder in ash or poplar, but if you wood has a stringy grain, it may be different.
The only thing I wish is I had a 30 or 36" cylinder, as our 8' truck load length are really 100" and I can't quite fit a length cut into 4 pieces (unless I do it just perfect) even though my stove will take 36" wood.
The valve you linked to is a open center "motor" spool valve. it is designed to let a motor free spool (spin) when you move the handle to the center and when used with a cylinder the cylinder could move from gravity it the verticle position.
The link below would be a better match other then the 2750 psi max relief setting, with skidsteer pressures exceeding 3400 psi, you may to check into a higher psi rated valve.
http://www.northerntool.com/webapp/wcs/stores/servlet/product_6970_472_472
Ken

Ken, Thanks for the link to the other valve. It's cheaper than the one I found too! While I think I wouldn't use the splitter vertically very often, I can see where having the cylinder free to move could be an issue! I do have some big pieces that I think I would rather roll over to the splitter and at least halve them, to save wear and tear on my back. I do plan on making side plates to keep pieces from rolling off. The whole idea is to make it as easy as possible on the humans! And I think you're probably right about never needing the full stroke of the cylinder, but there is always that piece that will have a knot at the far end. Thanks again.

 

[WayneShaw]

Ken, Thanks for the link to the other valve. It's cheaper than the one I found too! While I think I wouldn't use the splitter vertically very often, I can see where having the cylinder free to move could be an issue! I do have some big pieces that I think I would rather roll over to the splitter and at least halve them, to save wear and tear on my back. I do plan on making side plates to keep pieces from rolling off. The whole idea is to make it as easy as possible on the humans! And I think you're probably right about never needing the full stroke of the cylinder, but there is always that piece that will have a knot at the far end. Thanks again.

I have just about all my parts and pieces to begin, and I had a thought....... Why make this thing an attachment, why not make this on a stand, self supporting, and just pull the Bobcat along side and hook up the hoses? I use the Bobcat to haul the firewood pieces out of the woods since the terrain is a little rough, so I could continue to do that and not have to keep changing between the bucket and the splitter if it were free standing. Although the splitters powered by a gas engine and pump operate independently, why couldn't this be "independent" and just hook up hoses?

 

[OldMachinist]

I have just about all my parts and pieces to begin, and I had a thought....... Why make this thing an attachment, why not make this on a stand, self supporting, and just pull the Bobcat along side and hook up the hoses? I use the Bobcat to haul the firewood pieces out of the woods since the terrain is a little rough, so I could continue to do that and not have to keep changing between the bucket and the splitter if it were free standing. Although the splitters powered by a gas engine and pump operate independently, why couldn't this be "independent" and just hook up hoses?

Along that same line of thinking why not make it both. Give it legs for using it free standing but also have a quick attach plate on it to move it around.

 

[coreya3212]

Along that same line of thinking why not make it both. Give it legs for using it free standing but also have a quick attach plate on it to move it around.

Why not go a step further and make me one too!

 

[Tazza]

Why not go a step further and make me one too!

hahaha Corey, i like that one

 

[WayneShaw]

hahaha Corey, i like that one

OK everyone, thanks to all the input, I'm getting close to making this thing work. At least the rough version. There are things I plan on adding to it, but for now, I need to get this working to get some wood stockpiled, then I'll add the rest, and paint it. So my question is, even though it wouldn't take long for me to find out myself, is which of the machine lines is the supply, male fitting or female?

 

[coreya3212]

OK everyone, thanks to all the input, I'm getting close to making this thing work. At least the rough version. There are things I plan on adding to it, but for now, I need to get this working to get some wood stockpiled, then I'll add the rest, and paint it. So my question is, even though it wouldn't take long for me to find out myself, is which of the machine lines is the supply, male fitting or female?

I think I read a post on this a while back about the "correct" coupler and the answers were everyone does it there own way and it didnt matter. I ended up putting mine in the same order as My neighbour so I can use his attachments and vice versa....

So......where is my splitter???

 

[WayneShaw]

I think I read a post on this a while back about the "correct" coupler and the answers were everyone does it there own way and it didnt matter. I ended up putting mine in the same order as My neighbour so I can use his attachments and vice versa....

So......where is my splitter???

"So......where is my splitter???" Well, I think you would be happier if I worked all the bugs out of mine first! Since that may take several years......... Anyway, thinking about what you wrote, you may be perfectly correct. I suppose if I have fluid running through the valve, the valve will direct the flow properly. I guess. Anyway, if I hook it up bas-acwards, it won't be a biggie to switch the lines if need be.

 

[skidsteer.ca]

"So......where is my splitter???" Well, I think you would be happier if I worked all the bugs out of mine first! Since that may take several years......... Anyway, thinking about what you wrote, you may be perfectly correct. I suppose if I have fluid running through the valve, the valve will direct the flow properly. I guess. Anyway, if I hook it up bas-acwards, it won't be a biggie to switch the lines if need be.

Depending on your loader you may be able to lock the flow on in either direction. Your splitter simply won't work if the flow is reversed. No harm though. Believe the male on the loader should be pressure side.
Ken