isaaccarlson
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It will be going on a 22hp v-twin and will be running a 4 inch cylinder. I would like to get the cycle time up but don't want to over pump the splitter.
22 or 28 gpm pump?
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bore x stroke x rod dia needed as well as what you expect for cycle times. Control valve capacities as well as port sizes for CV as well as cyl. and what size hoses you intend to use. All this will come into play when trying to make speed and choosing pump size. You have the hp to pull either size pump you listed,,,, provided you are referring to 2 stage pumps and not single stage ones.
I have often wondered why my TW-6 has a 22 gpm two stage pump and a 18/20 hp engine(Honda GX 630), while the TW-5 has a 22 gpm two stage pump and a 13 hp engine (Honda GX340).
-Cycle time is posted as 8 seconds with a 24 x 5 x 3.5 cylinder(TW-6), and 10 seconds with a 24 x 5 x 2 cylinder(TW-5).
-the TW-6 has a dump valve and 20 gallons of hydraulic fluid vs 15 gallons on the TW-5
They both have the same pump. Splitting tons is 28 vs 25. (which relates to cylinder size, and assumes psi is the same)
So then Isaaccalson with a 28 gpm would need? Increased hydraulic capacity presumably for cooling, and a dump valve? Plus valves and hoses rated for 28 gpm.
So why do two splitters, the TW-5 and TW-6, with the same size pump have different size engines?
-Cycle time is posted as 8 seconds with a 24 x 5 x 3.5 cylinder(TW-6), and 10 seconds with a 24 x 5 x 2 cylinder(TW-5).
-the TW-6 has a dump valve and 20 gallons of hydraulic fluid vs 15 gallons on the TW-5
They both have the same pump. Splitting tons is 28 vs 25. (which relates to cylinder size, and assumes psi is the same)
So then Isaaccalson with a 28 gpm would need? Increased hydraulic capacity presumably for cooling, and a dump valve? Plus valves and hoses rated for 28 gpm.
So why do two splitters, the TW-5 and TW-6, with the same size pump have different size engines?
isaaccarlson
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The cylinder is 4x24 and the valve is rated for 30 gpm and is open center. The tank is of a vortex design to keep out air and cool the oil. The hoses are all short and I could go with 3/4".
A 3/4 inch hose is good for about 25gpm@3000psi. If you decide to go with the 28gpm pump, you can consider the actual pump efficientcy to be about 85% of advertise flow at the correct rpms. I think most of those pumps are rated for 3600rpms. so doing the math, your 28gpm pump will probably put out around 23-24gpm, so you will be good with your 3/4in hoses. You didnt give the dia of the rod, but typical rod size is 2". This would give you about 25% more oil flowing thru the valve on retract, than is going into the extend side. 23gpm X 1.25 would be 28.75gpm flowing thru the return. Your 30gpm rated valve will handle the flow without the need for a dump valve. But now your return port of your cyl and your 3/4in hose is starting to be marginable for size. When you consider that most folks dont run their splitter engines at max rpm, therefore they dont produce maximum flow. I would say your splitter will work just fine and be plenty fast using the 28gpm pump and the hoses and valves you already have. Actual cycle time would be around 6sec figureing a 24x4x2 cyl and 28gpm 2stage pump at 85% efficentcy.
isaaccarlson
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I am not planning on running it above 2/3 throttle anyway. I am currently using 1/2" hoses from the valve to a ported cylinder. I talked to Greg at Cross Mfg today and he said the lines form the valve to the cylinder should be fine for 28 gpm. The rest will be 3/4"+. I am not going to use any any 90* fittings and will try to reduce orifice effect as much as possible. The lines on the cylinder are very short since the valve sits on top of it. I may be able to make some larger diameter steel lines for the cylinder. I will need to weld in bigger fittings on my tank or just make a new one. My current tank is 5 gallons and barely gets warm. I would like to have 8-12 gallons of oil, but we will see what happens. I will need to add weight to the front to maintain balance. Maybe a log lift is in the works. 
I have no problem putting an oil cooler on it if needed.
I have no problem putting an oil cooler on it if needed.
I wont dispute a Cross rep, but I wont agree with him either. You stated you wanted a fast splitter. Using 1/2in lines from the valve to the cyl is going to reduce speed and act like the orifice you say you are trying to avoid. I am not saying the 1/2in hose wont work, but I will say using 3/4 is a better choice, unless your cyl only has 1/2in ports to start with. If that is the case, unless you want to change out the ports in the cyl to something larger, then stay with the 1/2in hoses.
isaaccarlson
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I don't want to use 1/2" lines, but they would work for a while, especially at 1/2 to 2/3 throttle.
A new development popped up today when I picked up the motor. There is a whole beam, pump, motor, etc...(not assembled) for sale for $100 that I am trying to get. If it works out I will be building a second splitter from scratch. The new motor will go on that one and the small splitter I have now will be the one to loan out to people I trust. I don't know what to do now but wait and see what happens with the parts. It would be nice to have a second splitter! The one I have now will split anything, so I don't know what the new one would do.
A new development popped up today when I picked up the motor. There is a whole beam, pump, motor, etc...(not assembled) for sale for $100 that I am trying to get. If it works out I will be building a second splitter from scratch. The new motor will go on that one and the small splitter I have now will be the one to loan out to people I trust. I don't know what to do now but wait and see what happens with the parts. It would be nice to have a second splitter! The one I have now will split anything, so I don't know what the new one would do.
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