want to build a log splitter, need advice

[Scooby074]

Yeah the calculations dont work, at least in my experience. It does this at wot and 3/4.

Perhaps the motor isnt a true 14hp. I looked at its power graphs and its "supposed" to be. Its a Robin/Subaru. Not a "Bad" name in motors.

I have the pump chart somewhere for that Barnes 22gpm unit somewheres. I think it specs out that 14 hp is required.. Ill have to try and find it.

 

[LD1]

Thats odd your 14 hp does that. Maybe you are right that it isnt a true 14hp, or it is getting tired.

14hp does make sense for them to "spec", since the numbers (3000psi x (6.5gpm) / (1714 x 85%eff) and you get 13.38hp required.

Its just odd that yours does it at such a low pressure where eve less HP is required.

I dont know how I & O get away with the 11HP honda unless it is a 16gpm pump or a 22gpm turned way down

Either way, like I said, anything between 14 and 18hp and you arent going to notice much difference in efficiency. Just keep it within reason. No need for a 27hp kohler to drive a 22gpm pump.

 

[Camdigger]

Yeah the calculations dont work, at least in my experience. It does this at wot and 3/4.

Perhaps the motor isnt a true 14hp. I looked at its power graphs and its "supposed" to be. Its a Robin/Subaru. Not a "Bad" name in motors.

I have the pump chart somewhere for that Barnes 22gpm unit somewheres. I think it specs out that 14 hp is required.. Ill have to try and find it.

It is baffling to me your engine isn't capable of running the pump. Log splitter pumps are usually Hi volume/low pressure combined with a lower volume/high pressure side for the extra oomph for the split. it almost sounds as if your pump isn't making the functional switch between the low pressure-hi volume side and the high perssure-low volume function.

BTW, what is the gpm output of the low volume setting? You have only given an output of 22 gpm, which I presume is the low pressure output. There should be two output rates for a typical splitter pump.
Are you running a pressure gage?

 

[Scooby074]

22GPM Barnes. P/N 1300488. Notice high flow @750psi peaks at over 14 HP (red line is approx 14hp).

I might have to adjust the shift point lower ... Not sure if i want to screw with it though. It splits everything as is

 

[Camdigger]

22GPM Barnes. P/N 1300488. Notice high flow @750psi peaks at over 14 HP (red line is approx 14hp).

I might have to adjust the shift point lower ... Not sure if i want to screw with it though. It splits everything as is

The source i came up with quoted 650 psi as the factory set point for max high volume output. Hmmm the plot thickens...

 

[LD1]

22GPM Barnes. P/N 1300488. Notice high flow @750psi peaks at over 14 HP (red line is approx 14hp).

I might have to adjust the shift point lower ... Not sure if i want to screw with it though. It splits everything as is

Are you saying that it is stalling on the HF-LP side?? I thought you said it was stalling above 2000psi which could care-less where the HF-LP side is set at.

And if you have enough power for it to shift with it set at 750psi, you certainly shouldnt be stalling at a tad over 2k on the LF-HP side

 

[Scooby074]

It was around 2500 on the high when i was getting it to stall. Earlier I indicated "over 2200" I wasnt really clear but,thats where I set the old pump to keep it from stalling out. Perhaps I could have tweeked it a bit more and got a few hundred PSI, but I had a problem with system pressures jumping all over the place and my autocycle valve was giving me fits.

I dont know where exactly I'm shifting right now.. Could be 650 as mentioned above? I dont think I ever had an issue with stalling on the LP side in operation, I did cause it to stall on lp when playing with the settings. My current pump is a new, warranty replacement pump and I havent begun to screw with it. So it's whereever the factory set it.

Northern says its rated 22GPM@650psi and 6.5GPM@2500. If its shifting at 650, that puts me at around 11 HP required. 11HP should only capable of pushing 2000 PSI with that pump.

Heres the same curve with ~11hp, 650PSI (LP) and 2000 Max press.shown in blue. 3000PSI is in Yellow. In order to hit 3000, you need minimum 16HP by that curve. The calculations say that shouldnt be the case though. It should be OK with less. Thats why I suggested going bigger than 14 and certainly bigger than 10 or 11 as Northern suggests. In practice the pump uses more HP than it should

 

[Camdigger]

If your pump is shifting and is stalling your 14 hp engine at 2500 psi, that is exactly what the red line in your diagram tells me it should, within 10 - 15%. That's about as close as I would expect under the conditions I would expect on a splitter. Oil viscosity and filter condition (if so equipped) as well as ambient (outside) temperature will all affect oil properties and back pressure.

 

[chad fitz]

Wow, al the info is great. mY background is custom woodworking and laser engraving. My neighbor will be doing all the fabrication in his steel shop. My job is the design and grociery shopping, and making sure this thing make splitting wood as comfortable and enjoyable as possible. Nothing worse thean using a splitter that has a tire right where you want to stand etc..... I split most of my wood alone, thereforethe splitter will have the capabilities of the second person that never shows. Again, thanks for the info, this is all helping very much.

 

[Scooby074]

If your pump is shifting and is stalling your 14 hp engine at 2500 psi, that is exactly what the red line in your diagram tells me it should, within 10 - 15%. That's about as close as I would expect under the conditions I would expect on a splitter. Oil viscosity and filter condition (if so equipped) as well as ambient (outside) temperature will all affect oil properties and back pressure.

I agree..
The whole point I was trying to get at was that Northern and Hyd Sirplus are saying that 10-11 hp is OK to use. You'll never see its rated output using that (aside from what IO and TW seem to be getting away with)

Curve calls for ~14 ish HP, but i could never get it reliable with MY 14Hp engine at 2500. I agree there can be outside factors as listed in your post.

Calculation says you can get by with 11.15 Hp@2500 & 6.5 GPM. (2500*6.5)/(1714*0.85) = 11.15 HP

Basically all im saying is follow the curve as the bare minimum and not the calculation when using these pumps, or you'll end up short on HP, doubly so when you start figuring in real world conditions like thick oil and other loads.

This is what burned me. I calculated (and read) ~12Hp to run the pump @2500 reliably. I stepped up a bit and went with a 14Hp engine. I still cant hit 2500 reliably. I really need 18 maybe 20 , in real world conditions.

I did not have the pump performance curve when I bought the pump for my machine. At the time, Barnes Haldex was sold (?) and changed names to Concentric, and all the old links to their manuals were invalid... And search engines hadn't updated to point to the proper place. If I had of seen the chart for the pump prior to purchase I'd never have went with 14 Hp. Probably 18 minimum. The upgrade cost at time of purchase isnt that bad.

Im trying to prevent others from the same issue.