Cycle time vs man power...

[Jags]

With all the log splitter questions and debates on cycle times, tonnage, blah, blah, blah, I thought I would throw out an observation made this weekend. (Mods - I debated what forum to put this in, wood shed or gear - move accordingly).

First - a few details. At home I have Mongo the homemade wood splitter. Big ram, big pump, log lifter, electric start will split, cut, crush anything that gets in its way. I run this splitter as a single person operation and plan to always do so. The cycle time is a bit slow, but for a single person I find that it will run me as hard as I care to run.

My second splitter was built on the opposite side of the spectrum. Smaller tonnage, Big pump (compared to cylinder) and FAST cycle time. This splitter was intended to be used at the river and most likely would include two or more users at a time. (if you bring a screwdriver outside with you, you will have at least one person interested in what your doing.).

Now, my observation - I will not give up Mongo - it will always be my goto machine at home for a single person operation. Mostly because it is a no brainer machine. Log on beam, pull lever, log splits, next. No concerns on placements, size or weight of log.

THAT being said....WOW, that little splitter with two people running it---and I do mean RUNNING, can put a whole lotta splits on the ground in short order. The one neighbor and I can work side by side on virtually anything and never need to speak a word. We just know what the other is thinking or what the next move will be. This guy and I split an entire 5x10 heaping trailer in about 45 minutes. Man is that little machine gonna work out just fine. I know, I know - pics or it didn't happen.

Moral to the story - match the machine to the man power. One person and slower cycle times doesn't appear to have a negative side. Two people with a fast cycle time - whoa, what a producer. If I would have had Mongo at the river, the machine would have slowed us down.

Edit: I think the little splitter will now be referred to as "Zippy"

 

[smokinj]

We can bust a cord and hour with good rounds with out "Y's. Had a truck load stolden on a site this weekend. We have been cherry picking it so that would not happen. Now the loads will be a slower and them hand pickers dont stand a chance!

 

[Flatbedford]

Good to hear that Zippy is working out for you.

 

[Jags]

Good to hear that Zippy is working out for you.

That thing rocks. It actually has a cycle time of just under 10 seconds (full cycle). And if you don't need the full stroke you can be split and moving on in just a couple of seconds. Literally, it had us running to keep up.

 

[Flatbedford]

That's the way I think a hydro splitter should work. Being a hand splitter, it always seems to me that I can split faster than a machine if I am working nice straight hardwood. Sounds like your machine would give me a real run for my money. Maybe I'll have you build one like that for me when I get tired of swinging the maul.

 

[Backwoods Savage]

I agree with most of what you say Jags but one thing I never like when working with machinery like this is hurrying. I was thinking about this today as I sat there calmly splitting wood. Sure, two men can work together and we have done that and easily split a cord of wood in less than an hour and we did not sweat either. We also did this with the splitter vertically, which is the correct way to split wood.

For me, it is work steady and easy and not hurry. It is just too darned easy to hurt someone or yourself when doing things in a hurry up mode. I also found that when splitting like I do that seat height makes a huge difference. Some have said they tried it and did not like it. Perhaps their seat height just was not right?!

 

[Jags]

We also did this with the splitter vertically, which is the correct way to split wood.

Dennis - the guy I was working with is 6'6" tall and weighs about 300 pounds. I ain't asking him to crawl around on the ground. With as fast as I had to fetch wood (I was on the trailer side) there is NO way that I could have done the same production without being bipedal. We were not at a speed that breeds danger, but at the top end of the production output that the machine would allow. And its pretty darn fast.

As you can see from the pic, this splitter sits taller than most (about the same as a super splitter). We were not rocking any big rounds. Most was a 2 way or 4 way split.

Edit: For the record, the only thing I do calmly is sit with a beer and stogie in hand, otherwise I am a mover. (I don't make a good sit-er-down-er).

 

[Backwoods Savage]

Jags, if you are taking wood off a trailer or wagon, then splitting horizontally would be the right way to go unless they were really big things. One would still need a table on the splitter or so it seems. And at 6'6" and 300 lb, I would definitely want that man for a friend!

That splitter looks like a heavy beast too. You can take pride at building them yourself.

 

[Jags]

Jags, if you are taking wood off a trailer or wagon, then splitting horizontally would be the right way to go unless they were really big things. One would still need a table on the splitter or so it seems. And at 6'6" and 300 lb, I would definitely want that man for a friend!

That splitter looks like a heavy beast too. You can take pride at building them yourself.

That is exactly how it was happening. Trailer parked 3 ft away, turn grab round, drop on beam, split, next. If it needed to be resplit my buddy grabbed it and did the resplit while I was reloading. Oh - and it has a table now, I just don't have any current pics.

Yeah, my buddy is a good dude and definitely one to have on your side. Ex military, Harley riding, true outdoorsman, sharp shooter, beer drinking, got your back type of guy. Don't get on his bad side - I have seen that happen. (actually he looks alot like Hogz, except he cut hit tail off last fall).

 

[clr8ter]

Now this is interesting. I have a rented 35T Husky Splitter, (from Tractor Supply). I think this machine has a slow cycle time. I have been imagining lately that a much faster cycle time would be nice. Meaning, I wouldn't have to stand there and wait so long for the ram to come back to full retract. (This is working by myself. With the wife, it's not so bad.) The only reason I can think of as to why this is not done is because of cost. Faster times would mean bigger pump, more GPM @ same pressure, and probably a bigger motor to run the bigger pump. Correct?

 

[Backwoods Savage]

clr8ter, the 35 ton splitter have a bad reputation on cycle time. Usually I don't get hung up on the cycle time but if they are super slow then I can see the concern. I think if you rented a 22 ton you'd see a big improvement.

 

[PapaDave]

The 27 ton I have seems slow to me too. Suits me.
I don't let it retract all the way. I stop it close to the size of the next round, which is normally about 16".
That splitter and I usually fill (1/3 cord) the 5x10 trailer in about an hour, and I shut 'er down while moving splits into position every few minutes.
There are times I would like it to be quicker, but I'd probably just hurt myself if it was.

 

[nate379]

Might speed up the splitter to use correct length hoses instead of what you have, would be less restriction. The one that is laying across the engine, looks like you have enough hose there to make 3 or 4 or them to fit for that connection.

 

[Jags]

Might speed up the splitter to use correct length hoses instead of what you have, would be less restriction. The one that is laying across the engine, looks like you have enough hose there to make 3 or 4 or them to fit for that connection.

The hoses used are what I had. Yes they are too long but you would NOT see any quantifiable speed difference shortening those hoses. Hydraulics is a positive displacement worker. One unit in, one unit out. What it WOULD do is reduce friction (read: heat), but I am already against all the rules. That is 3/8" hose running at 16 gpm. It shouldn't work, but it does, and quite well. I also have a fair size tank running about 8 gallons of hydro juice on it and it is aluminum so it dissipates heat well.

Edit: Nate - you may not have seen the original build thread for the splitter, but I intentionally tried to do a budget build. I have less than $300 in this splitter.

 

[Jags]

Now this is interesting. I have a rented 35T Husky Splitter, (from Tractor Supply). I think this machine has a slow cycle time.

This is the reason for the post. My observation has been that a single user can get away with a slower cycle time without giving up much in production. However the same doesn't hold true when you have more than one worker. It sounds pretty much like dumb logic, but some things I have to prove to myself.

 

[smokinj]

clr8ter, the 35 ton splitter have a bad reputation on cycle time. Usually I don't get hung up on the cycle time but if they are super slow then I can see the concern. I think if you rented a 22 ton you'd see a big improvement.

How we get more out of one is one guys sets the round into place and the OP throws the splitts into the trailer. Hydro never stops from open to close of the day. (Even fuel is added while running)

 

[nate379]

I'm curious if you did the math on that hose or just used it? I'm not posting this to insult you or be "that guy", but I did some rough math... mind you this is just quick math based on flow.

In a 5ft long 3/8" hose at 16gpm you loose almost 80psi!... it's about 16psi/ft. If you had 15ft of total hose on the splitter that would be about 240psi pressure drop just in the hose. That isn't figuring in any couplers or valves.

Now take 5ft of 5/8" hose and the pressure drop is 6psi, or about 18psi drop in 15ft.

I'm a cheap bastard as well, if I wasn't I doubt I'd heat with wood, but I'd hate to see you spending a dollar to save a dime.... replacing a short lived pump over "saving" $100 in hoses.

The hoses used are what I had. Yes they are too long but you would NOT see any quantifiable speed difference shortening those hoses. Hydraulics is a positive displacement worker. One unit in, one unit out. What it WOULD do is reduce friction (read: heat), but I am already against all the rules. That is 3/8" hose running at 16 gpm. It shouldn't work, but it does, and quite well. I also have a fair size tank running about 8 gallons of hydro juice on it and it is aluminum so it dissipates heat well.

Edit: Nate - you may not have seen the original build thread for the splitter, but I intentionally tried to do a budget build. I have less than $300 in this splitter.

 

[Jags]

Nate - when my pressure gauge reaches the relief pressure of 2750 it bypasses the relief. I don't care if it got there with a 1/4" pipe or a 3/4" hose - it still reaches the same pressure. No pressure drop.

In your garden hose example if you cap the end of a 1/2" hose, it will reach the same pressure as capping a 3/4" hose. Now FLOW is a different thing.

If you have an air compressor with a gauge at the tank that reads 100 psi and a 50ft hose connected with a gauge and capped off, the other end will read 100 psi. Its when you use the air that you see a pressure drop. That is an example of flow (volume) not pressure.

Now add in the fact that fluid cannot be compressed and its a whole nuther thing. One unit in, one unit out.

 

[nate379]

You are a bit confused on how fluid flow works. I'm not an engineer mind you, but I did go to school to work on hydraulics.

Sure there is no pressure drop when the fluid is not flowing, but the machine isn't working then. The concern is when that oil is flowing at 16gpm. If you have a pressure drop in the system of 300psi with small hoses vs 50psi with correct sized hose which machine will be more efficient?

If your pump was only putting out say 5gpm, that 3/8" line is still too small.

 

[Jags]

The system doesn't build pressure (negligible) until the ram meets wood. At that time when the gauge reads xxx pressure, either wood splits or the system stops (regulated to 2750). The only flow is at the bypass and it is at the rated pressure. Where am I loosing ANYTHING. The only thing those small hoses do is increase resistance which will increase heat. Until the pump hits 2750 and bypasses I am at all the flow and pressure that the pump can produce. The pump volume and pressure settings is the limiting factor. Until the hoses are small enough that the pump pressure rises past the preset relief pressure, those hoses will carry the full volume that the pump can produce.

Thinking about this...if anything, going from a large hose to a small hose will INCREASE pressure. Think about putting your thumb over the end of a running garden hose. You MUST differentiate between pressure and volume.

I think I understand your argument. Let me see if I get this right:
a 1/2" hose at 1000PSI has the ability to move xxx volume.
a 3/4" hose at 1000PSI has the ability to move much more volume.

Is this the argument? If so, there is no argument. BUT that is a function of FLOW, not PRESSURE. Note that they both have the SAME pressure. Using a smaller hose is a restriction of FLOW which will increase Pressure to do the same work which is a non-issue unless one of two things happen.
a) the pressure runs high enough under no load that the 2 stage pump kicks into low gear or
b) the pressure at no-load exceeds the pressure relief setting.

Neither happens.

(Nate - I do like these type of discussions. Even if I am wrong, I learn something.)

 

[clr8ter]

Backwoods Savage, I have this splitter because I know the owner. I get it for $100 flat rate for however long I need it. The rental place gets $69/day. Better to be slow and take your time.....now if I were to build one, that would be a different story.....

 

[Backwoods Savage]

clr8ter, that is a good deal. I'd stick with it! Good for you.

 

[nate379]

It's hard for me to explain, I'm not a great teacher... maybe someone else can chime in?

This is a good tool to use, plug some #s in and see what I mean...
(broken link removed to http://www.gates.com/industrial/pressure/fluidFlow.cfm?location_id=3044)

A general use hydraulic oil is around a 10wt, 0.8 specific gravity, though I have no idea what you have in your splitter.

If you use 5ft 3/8" hose and put 3000psi at one end with 16gpm flow, at the other end it would only be 2920psi.
Same length hose, same flow/psi but 5/8" you have 2994 psi. This is just regular pressure drop, applies to pneumatic systems as well and electricity too (voltage drop).

When you put your finger over a water hose end and it makes higher pressure you are reducing the volume that is coming out.

Doesn't seem that bad, but add up all the hose, connections, valves etc and it can get ugly. Maybe not so much on a simple circuit of a splitter I guess though.

And yeah I like these types of threads as well, learn something usefull in the end usually. Lot better than reading about "boo hoo my glass is dirty, my wood is too wet, etc" haha

 

[Jags]

And yeah I like these types of threads as well, learn something usefull in the end usually. Lot better than reading about "boo hoo my glass is dirty, my wood is too wet, etc" haha

Baahaha - so true.

But in the end, I trust my gauge that is mounted to the input of the "push" side of the cylinder. If it says 2750 psi at max, I believe it.

 

[Dune]

It's hard for me to explain, I'm not a great teacher... maybe someone else can chime in?

This is a good tool to use, plug some #s in and see what I mean...
(broken link removed to http://www.gates.com/industrial/pressure/fluidFlow.cfm?location_id=3044)

A general use hydraulic oil is around a 10wt, 0.8 specific gravity, though I have no idea what you have in your splitter.

If you use 5ft 3/8" hose and put 3000psi at one end with 16gpm flow, at the other end it would only be 2920psi.
Same length hose, same flow/psi but 5/8" you have 2994 psi. This is just regular pressure drop, applies to pneumatic systems as well and electricity too (voltage drop).

When you put your finger over a water hose end and it makes higher pressure you are reducing the volume that is coming out.

Doesn't seem that bad, but add up all the hose, connections, valves etc and it can get ugly. Maybe not so much on a simple circuit of a splitter I guess though.

And yeah I like these types of threads as well, learn something usefull in the end usually. Lot better than reading about "boo hoo my glass is dirty, my wood is too wet, etc" haha

Sure, I'll chime in, but then someone will kill the thread.

Jags is right and wrong. He is right that he has plenty of pressure but he is wrong to use a 3/8" hose on a machine whose entire point is to go fast, and don't forget Jags, heat is WASTE. Surplus Center sells most diameters of 2 wire hose in various lengths for very reasonable prices.

http://www.surpluscenter.com/sort.asp?catname=hydraulic&keyword=HHNC