Splitter project question... 2 stage or 1 stage.

[FlyingDutchman]

Question for you guys: MUCH of this splitter is made from NPT pipe fittings from the hardware store. I know its the smart thing to do to go with real hydraulic fittings, but, generally what I'm finding is that standard A53/Schedule 40 pipe 1/2" has a 6-10K burst strength but "only" a useable working PSI of 1200-1400psi. The cast fittings (which is entirely what I have) may be more or less. Just looking for input on that as I order more pieces for this thing...

I need to order at least a 3/4" hose for the return for the filter, but to do my sequence valve etc, I've got to disturb the fittings on the cylinders and install tees and not sure which direction to go.

A little more narrative on the progress:

Took hours to get the old pump shaft woodruff key out. Had to alternate heating and cooling the shaft with freeze spray then was able to pound it out like a rocking chair with a pin punch. Turns out, the SAE #505 works for the new series but not the old series pump. Back to the hardware store with the old key.

When I got the jaw coupling, only got one for a 7/8 motor shaft, not a 1". In my defense someone had scrambled the things on the rack.

Got the wiring harness out of the mower. Working on a plan with a wiring diagram to use the Cub cadet harness and eliminating the hydrostat stuff, the brake and seat interlocks, and only have the stuff critical to the lights and the engine so I can run the engine off the ignition switch and add work lights later if I want

 

[FlyingDutchman]

I did a bunch of reading on the pipe fittings and it seems like its a common thing for "tinkerers and handymen" to use them for a log splitter application (with no real stories about failure, and lots of speculation and confusion about pressure ratings).

Had a 3/4" return hose fabricated for $25. Was actually slightly cheaper than Surplus Center with shipping and swivel fittings (lots of their hoses don't have swivels.)

The list to do yet reads like so, kind of overwhelming:

Drill holes for new 3/8 and 3/4 return bungs and prep them to be welded to the tank.

De-pin lawnmower harness and remove interlocks. Attach mower dash with throttle, choke and ignition to splitter.

Measure old pump bracket and new motor for amount to raise pump bracket. Cut off bracket. Drill new mounting holes for engine, bolt on.

Align the pump and bracket off of coupling... Reweld.

Attach lawn mower gas tank to splitter frame and plumb fuel line to engine.

Plumb return line and return filter. Plumb pump pressure hose. Plumb pump suction hose.

Buy and mount battery.

Find 13" scab tires for the rims, or find different 5x100 rims and tires.

 

[Sandhill Crane]

Sounds like a typical problem solving project, with many trips to town.
Myself, I would go with hydraulic fittings and piping on the pressure side of things.
The "What if..." of a black pipe failure is unpredictable and open ended.
You may choose to take that chance, and it is your choice to do so.
However, you inadvertently involve others who may be helping stack wood, etc., or using the machine two years from now.

Accidents... It is a funny word. Often misused, or disguised.
Typically, accidents are a series of events. Had any one thing in the sequence changed it may have been avoided all together.
Often a series of 'poor' choices that train wreck.
Google fluidpowersafty.com (fluid power accidents)
The first accident I read about was a service tech pulling a hose on a system that was not de-energized.
He got a pin hole blown in his check and oil in his mouth.
Apparently this type of accident is not so uncommon.
As home owners we benefit from great inexpensive technology and equipment.
Maybe black pipe reads strong enough by the numbers to you, but perhaps it fatigues differently from vibration and peak pressures found on mobile equipment.
If I'm cutting corners, it's drinking three Cokes a day, not four.
A dollar fitting, or eight dollar fitting? Sure $8.00
I need ten of them... $80.00???? $8.00????
Slippery slope...
Edit: If $80., or even $300., seems like a lot, see how far it goes in the health care system, or a funeral home.

 

[FlyingDutchman]

I've viewed safety videos on the subject. The wounds themselves are not all that gruesome, its the gangrene from untreated wounds or the surgery to remove the injected oil that really gets vomit-worthy.

Based on the numbers, I'm okay using the existing pipe fittings for now, but I intend to update them especially if my system pressure is raised to 3000psi with a dual stage pump.

 

[Big_Eddy]

Your single stage pump has the same maximum pressure as a dual stage pump - whatever your relief is set to. The 2 stage pump adds a higher volume low pressure stage only - does not increase the max pressure available.

 

[FlyingDutchman]

My current pump is only capable of 2000psi. Higher psi will blow out the shaft seals. A dual stage would be capable of more as they are usually rated for 3k psi. Will have to check and adjust relief valve on the control valve for each different pump. Its questionable if the old motor was even capable of 1500psi based on pump output charts.

Haha... 22 ton splitters are on sale for like $799 right now! Screw this mess!

 

[muddstopper]

My current pump is only capable of 2000psi. Higher psi will blow out the shaft seals. A dual stage would be capable of more as they are usually rated for 3k psi. Will have to check and adjust relief valve on the control valve for each different pump. Its questionable if the old motor was even capable of 1500psi based on pump output charts.

Haha... 22 ton splitters are on sale for like $799 right now! Screw this mess!

some times the cheapest option is often the best option

 

[FlyingDutchman]

So far, cheapest option is to have this splitter and pump combo work. I'm almost there... Want to say we are under the $400 mark. Lots of hours spent already...

Looks like dad has some time tonight to cobble on it with me.

I finally sold my old car, however, all the 5x100 rims (including the rollers I had that I had on the splitter) went with it. Trying like heck to find 13" tires or some 5x100 doughnut spares to put on the old rims. I can borrow some doughnut spares from a friend, but he wants them back in the spring, so I put a feeler on craigslist.

Since the pump woodruff key I have is smaller than the keyway on the jaw coupler, I'm thinking about shimming it out with some tiny strips of roof flashing.

 

[blades]

Buy the larger woodruff key and carefully file it down to match the pump. chances are those shims won't stay put. If you do not feel confident that way- add solder on to the the smaller key so you can get a press fit on/in the coupler shaft. ( old farm trick)

 

[FlyingDutchman]

Wow thats an awesome idea. I don't think the filing will work, I ran out of patience taking out the old key..

I wonder if I fill the shaft way with flux if I can just pour a bit of hot solder into the keyway...

 

[blades]

Never tried it that way, but you would have to heat the shaft and key. if the coupler shaft has rubber components that might not work out to well. Most solders now days are lead free- bit more finnicky to work with. it would be an acidic flux for this work not the same as electrical.

 

[FlyingDutchman]

Dad decided, that the 5/8 coupler was too loose on the pump shaft, and there wasn't a good way to fix the keyway issue. So I bought a 1/2" coupler *which has the right keyway, but is too small* and hes going to have the coupler machined to the correct size then the keyway broached for the correct size. He has a machinist friend at work that will do quick side work for cheap.

I have the splitter on some doughut spares currently, which works just fine to roll it around. They will probably stay there.

We are swapping positions on the motor and hydraulic tank to put the motor on the same side as the control valve operator... So we can operate the throlttle/ choke etc... Now my 3/4" return hose is too short, but I will remedy it with the location of the tank return port and a longer 3/4" pipe nipple. D'oh.....

 

[FlyingDutchman]

The motor and the pump are 90% matched up. Its tacked just needs welded solid. What a gob of work!

Found some cheap new hydraulic tanks on Facebook marketplace. going after them. 17 gal will probably be okay for a 28 GPM pump, but they also have a 25 gallon one for cheaper but no bungs or accessories. 17 gal is decked out with temp gauge, fill cap, inlet strainers etc. Pretty sure I'll go after the 17gal one.

Still haven't done the fuel tank or wiring harness yet...

 

[CylinderService]

An important function of the tank is cooling the oil, and log splitters running for hours at a time, especially in hot weather, are notorious for overheating. The rule of thumb is a minimum of one minute's worth of oil in the tank, ie, 28 gal. in your case. We don't sell tanks, so that's not the object of this comment.
It will certainly work with a smaller tank, but overheated oil doesn't lubricate well, which will ruin rubber components and seals, and shorten pump life. I usually recommend keeping the max. temperature under 150 deg. F.
Also, I don't recommend over 2500 PSI for gear pumps. 3000 is a maximum, not the pressure it should be run regularly. I might run my little Toyota truck 100 mph back & forth to work (assuming the cops would let me), but the maintenance bill would probably be above average!

[email protected]

 

[FlyingDutchman]

Don,

Current pump is only capable of 10 gpm @ 2000 psi, but I intend on upgrading to a 22-or-28gpm 2stage pump capable of 3000 psi (later... If the expected abysmal cycle times are a chore). Its also only 4 gallons. It also needs extensive modification to work in my current configuration.

The 17.5 gallon reservoir is 7x12x48 with a total surface area of 1992 square inches. Looks similar to the ones they use for Speeco splitters with the tank below.

The 25 gallon reservoir is 20x20x15 with a total surface area of 2000 square inches.

The heat loss capacity of the 17 gal one being almost the same as the 25 gallon one, I'm tempted to say that when talking about heat loss, the two reservoirs will perform about the same, the one with more capacity will just heat and cool slower because of more volume.

I don't intend running 3000psi the whole time, just when under a load, which isn't a whole lot of time. Plus, this being an older motor with high hours, a 28 gpm pump is on the edge of its performance capability and probably isn't the greatest idea anyway.

 

[CylinderService]

Having a flat tank does give you more surface area so the steel surface is very close. But the larger volume of oil means it gets more time in the tank before recirculating. It may be fine - the oil temperature on a hot day is the determining factor of course, not our predictions.
I know those pumps are rated for 3000 PSI (we sell them), but they're still gear pumps, and they'll last a lot longer if the relief is set for 2500. Logsplitters often spike to the relief pressure at the each end of the cylinder stroke. Maybe only one end if you're using an auto-detent valve. Better to throw away that one knotty piece than ruin your splitter.
Just my thoughts
[email protected]

 

[FlyingDutchman]

Definitely. Interesting that the pressure spikes being mostly on the end of the stroke. I do not have an auto return valve, unfortunately. I'm definitely no stranger to cross cutting some logs or using sledge andwedges. I've spent some long hours with my scruffy Poulans cross cutting logs.

What I've read is, that the only thing that drives the need for dwell time in the tank is deaeration. It gives the system time to shed air from cavitation etc before recirculating. If you have inlet screens and return diffusers it reduces turbulence in the tank, and reduces pressure differential and tank the need for oil volume for dwell time. The longer tank (may) help by putting distance in there too between return and suction. I don't know, can't seem to find the time to go get the stupid thing.

Dad keeps saying this splitter worked great as it was, and if it didn't split it, it would smash it.

 

[Sandhill Crane]

CylinderService: (edit)
I have often been confused about wood splitter cylinders. They are advertised using two numbers, the cylinder dia., and the stroke. What about rod size? The Timberwolf TW-6 runs a 5" x 3 1/2" x 24" cylinder (unsure of the proper numerical order) That third number makes a huge difference. And there should be a forth number indicating max. pressure. I recently read one manufacturer uses higher psi with smaller, or rather average, sized cylinders. I do not remember if this increased speed, or tonnage. Seems like tonnage for sure and possibly speed, but obviously every component must be designed to handle higher pressure. Valves, hoses, fittings, pump and cylinder, not to mention structural design as well.
Why don't we see 5" x 3 1/2" x 24" cylinders listed for sale for wood splitters? Are these custom built for Timberwolf?

 

[CylinderService]

Flying Dutchman: The more time the oil spends in the tank, the cooler it will get. And turbulence contributes to cooling as the hot oil is continuously thrown against the steel tank walls. Industrial tanks have a baffle down the center with the suction port on one side and the return on the other, preferably at the same end of the tank, with the baffle between. The baffle has through holes at the opposite end so the oil has to flow down and back.

Sandhill: We often add the rod diameter to the cylinder "number", ie, bore x stroke x rod. 5 x 24 x 3.5 in your example. Pressure is certainly another important characteristic, but there are several others that are also important. Mounting type and dimensions for instance. When we spec out a custom cylinder we have a whole list of characteristics to specify.
With a 3.5" rod, that is a custom cylinder for Timberwolf. Most cylinders in this world are custom designs for their application. The standard cylinders we see in various catalogs are just a small fraction of hydraulic cylinders built. Prince Mfg, whose cylinders we carry, makes thousands of standard cylinders each year, but actually 75% of their business is custom cylinders for various OEM's, including many of the big names of construction and other equipment.
Modern construction equipment uses smaller diameter, but higher pressure cylinders, and they greatly increase productivity. With the same flow, the cylinders move much faster. And the increased pressure gives them the same force as a larger diameter, lower pressure cylinder. They have to be built a lot stronger of course, and more precisely, to withstand the high pressure (4000+ PSI) and speed, so they cost a lot more. But they have completely taken over the market in the last 20 years or so because the machines can do so much more work in a day.

Enough for today!

[email protected]

 

[GM_Grimmy]

Also with the bigger rod in the cylinder, you create a lot higher flow on the return stroke, and you need the proper pluming and equipment to handle that flow. I had my cylinder worked on and went to a 3.75" rod on my 5" cylinder, cause I wanted a fast return stroke. I had to plumb in a dump valve as I was calculating up to 65 gpm of flow on the return stroke. Speed in a hydraulic splitter costs money.