another splitter build

[jags]

I bought a 5" bore 30" stroke cylinder from northern tool last summer and it has 3/4 ports (which is why i got it). Its made by Prince, cost around $500

I plan on running a 28gpm pump so thats why i want bigger ports

Absolutely all of these numbers flop around when you start talking bigger pumps. I don't blame you a bit.

Just giving a real world example of a pretty common question about common components for our log splitter folks.

 

[origionalrebel]

was looking at a chart from parker and it says the max. velocity desired is 20 ft. per sec. for hydraulic hose. 1/2 hose at 22gpm is close to 30ft. per sec. according to that chart the biggest pump running through a -8 hose should be about a 14 gpm. 22gpm through a -12 gives about 12 ft. per sec. i agree the splitting force won't change one bit with a restricted system but the speed will suffer. it'll still have the same end pressure but take longer to fill the cylinder at a given pressure. kinda like throwing water through a screen door.

 

[jags]

was looking at a chart from parker and it says the max. velocity desired is 20 ft. per sec. for hydraulic hose. 1/2 hose at 22gpm is close to 30ft. per sec. according to that chart the biggest pump running through a -8 hose should be about a 14 gpm. 22gpm through a -12 gives about 12 ft. per sec.

You are correct. They also state that you should have double the pump volume in reserve....you don't see that either.
As tough and mean as a splitters hydraulics is, it is far from the same type of beating that industrial equipment take. At full stroke, the splitter is usually only working for about 1 second.

I am not denying the advantages of properly sizing hydro stuff....really...but in the world of log splitter - some of this stuff is really splitting hairs.

 

[Hedgerow]

You are correct. They also state that you should have double the pump volume in reserve....you don't see that either.
As tough and mean as a splitters hydraulics is, it is far from the same type of beating that industrial equipment take. At full stroke, the splitter is usually only working for about 1 second.

I am not denying the advantages of properly sizing hydro stuff....really...but in the world of log splitter - some of this stuff is really splitting hairs.

So what you're sayin', is my 20 gallon reservoir is overkill...
:msp_rolleyes:

 

[origionalrebel]

You are correct. They also state that you should have double the pump volume in reserve....you don't see that either.
As tough and mean as a splitters hydraulics is, it is far from the same type of beating that industrial equipment take. At full stroke, the splitter is usually only working for about 1 second.

I am not denying the advantages of properly sizing hydro stuff....really...but in the world of log splitter - some of this stuff is really splitting hairs.

i completely understand the fact i can use a 11 gpm pump and get the same splitting force i can get with a 28gpm pump. just takes a while to get there. my aim is to get under a 10 sec. cycle time with a 5 in. bore. i'd want to cry if i built one from scratch that didn't outperform my buddy's troybilt.

 

[jags]

So what you're sayin', is my 20 gallon reservoir is overkill...
:msp_rolleyes:

Well....your not gonna hurt anything but your wallet.:biggrinbounce2:

 

[jags]

i completely understand the fact i can use a 11 gpm pump and get the same splitting force i can get with a 28gpm pump. just takes a while to get there. my aim is to get under a 10 sec. cycle time with a 5 in. bore. i'd want to cry if i built one from scratch that didn't outperform my buddy's troybilt.

Yep, but none of my posts had to do with force, that is a little different (but kinda the same).

Sounds like you are setting up some nice components.

 

[Hedgerow]

i completely understand the fact i can use a 11 gpm pump and get the same splitting force i can get with a 28gpm pump. just takes a while to get there. my aim is to get under a 10 sec. cycle time with a 5 in. bore. i'd want to cry if i built one from scratch that didn't outperform my buddy's troybilt.

I think you'll get there with what you're proposing... What did you plan on as far as a power plant for this beast?
28gpm pump may need some real power.

 

[jags]

28gpm pump may need some real power.

It will need 14hp or more to pull the pump to its rated pressure.

 

[midwest_170]

was looking at a chart from parker and it says the max. velocity desired is 20 ft. per sec. for hydraulic hose. 1/2 hose at 22gpm is close to 30ft. per sec. according to that chart the biggest pump running through a -8 hose should be about a 14 gpm. 22gpm through a -12 gives about 12 ft. per sec. i agree the splitting force won't change one bit with a restricted system but the speed will suffer. it'll still have the same end pressure but take longer to fill the cylinder at a given pressure. kinda like throwing water through a screen door.

The only reason they are recommending that is to keep the pressure drop down in the system. If you have 1/2" vs 3/4" hose, your pressure and flow rate will remain basically the same. The amount of increased pressure is so small that your flow rate (cycle time) will remain basically the same. So the same amount of fluid is getting to the cylinder, but with the smaller hose it's just traveling faster creating a little higher pressure drop. I could see where it might be worth it if the cylinder was on 30-50 dollars higher, but 300 dollars higher for gaining less than half a sec in cycle time just doesn't justify itself to me.

 

[ziggo_2]

Absolutely all of these numbers flop around when you start talking bigger pumps. I don't blame you a bit.

Just giving a real world example of a pretty common question about common components for our log splitter folks.

i didnt really read the whole thread, i just seen someone was looking for a 5" cyl , with 3/4" ports so i simply stated where i got mine and what it cost.

 

[origionalrebel]

I think you'll get there with what you're proposing... What did you plan on as far as a power plant for this beast?
28gpm pump may need some real power.

i'm actually looking at using a 16 or 22 gpm pump. haven't decided yet. most likely use pto power unless i can run across a deal on an engine. will be built so i can change later. from what i can gather, a 22gpm pump should be about spot-on for the 5 in. bore. if you use one of them speed calculators it says about 7 sec. cycle but i don't think it would do that with -8 ports. jmo

 

[Hedgerow]

The only reason they are recommending that is to keep the pressure drop down in the system. If you have 1/2" vs 3/4" hose, your pressure and flow rate will remain basically the same. The amount of increased pressure is so small that your flow rate (cycle time) will remain basically the same. So the same amount of fluid is getting to the cylinder, but with the smaller hose it's just traveling faster creating a little higher pressure drop. I could see where it might be worth it if the cylinder was on 30-50 dollars higher, but 300 dollars higher for gaining less than half a sec in cycle time just doesn't justify itself to me.

Then what combo would it take to get a ~6 second cycle time???
Dare I ask???

 

[wndwlkr]

i'm actually looking at using a 16 or 22 gpm pump. haven't decided yet. most likely use pto power unless i can run across a deal on an engine. will be built so i can change later. from what i can gather, a 22gpm pump should be about spot-on for the 5 in. bore. if you use one of them speed calculators it says about 7 sec. cycle but i don't think it would do that with -8 ports. jmo

Thats exactly right. those speed calculators only factor in gpm, which means if you if you type in 22gpm thats what you need to put through the cylinder to get that speed. any restrictions will be less.

 

[wndwlkr]

Then what combo would it take to get a ~6 second cycle time???
Dare I ask???

Less restrictions

 

[Hedgerow]

Less restrictions

I can put the same amount of fluid through a 1/2" hose in a second as I can a 3/4" hose by just adding a little pressure...
Question is...
How much???

 

[midwest_170]

Then what combo would it take to get a ~6 second cycle time???
Dare I ask???

A pump with a higher flow rating.

Sent from my C771 using Tapatalk 2

 

[wndwlkr]

I can put the same amount of fluid through a 1/2" hose in a second as I can a 3/4" hose by just adding a little pressure...
Question is...
How much???

short answer no. unrestricted flow and let the wood build the pressure.

 

[Hedgerow]

A pump with a higher flow rating.

Sent from my C771 using Tapatalk 2

How much higher???

 

[Hedgerow]

short answer no. unrestricted flow and let the wood build the pressure.

Long answer...
What you just said makes no sense...
If a 22gpm pump will move 22 gpm in the primary stage, and it can flow through a 3/4" hose with say ~20lb of pressure, would it not still flow 22gpm through the 1/2" hose at say~40lb of pressure??? Both well within the primary pressure of the pump???