powering a log splitter. ideas?

[payton]

I have wanted to build a log splitter for a few years and have access to an I/H beam 8X8", 35 lbs/foot for $9 a foot. this seems like a great deal compared to what i normally see.
I am a collage student studying mechanical Engineering and don't have much free time outside of breaks, so i would want to get this done during the 3 weeks i have off for Christmas.
I do not know what I am going to use to power this, i have a 2hp balador motor that had a water pump bolted to it's face. also have a 1.5hp and a .75 hp electric motors sitting on unused projects. I would like to stay away from buying a small gas engine if at all possible.
I would like this to be something that can ether A. split logs extreamly fast. or B. can split any huge log I throw at it. i want to build something that is better than the expensive splitters at home depot or lows. I am hoping to turn this into a business for me and my 14 year old brother. (the job i worked for the last 3 summers no longer exists) eventually i would like to have a splitter based off this ram?(https://www.surpluscenter.com/item.asp?UID=2009120315321385&item=9-7178&catname=hydraulic) that will cycle in under 5 seconds. and another splitter to do hard/big stuff and/or use a 4 way wedge.
i have some more things in my head i would like to post but i don't want to ramble on to bad.


Thanks for any help.
Payton Hand

 

[kennyd]

Welcome to TBN Payton

I don't see how you are going to do much with those small electric motors...and that cylinder you linked is VERY small. Most splitters use a 4"x24" cylinder.

What is your budget?

 

[J_J]

I would suggest to do a search for LOG SPLITTERS on TBN, and read all the data available. This the smallest 2 stage log splitter pump they make. and it needs 4 HP. If you think you have an electric motor that is equivalent, it might work. 8 GPM at 650 psi needs 4 HP

https://www.surpluscenter.com/item.asp?UID=2009120318291417&item=9-7503-8&catname=hydraulic

Cycle time with that pump is 4.09 sec to extend. and 3.10 sec to retract. Total cycle time would be 7.19 sec.

Most you going to get is about 8 ton.

 

[6sunset6]

I have a splitter I converted from a gas engine to an electric motor. The problem with electric motors is if you have only single phase You are kind of limited. If you have 3 phase you are golden. Lets assume single phase.
What ever you do the pump must run at 3600 rpm. So either a motor running at that speed or a pulley set up. The pulley ration would pretty much be 2:1 with 2 on the motor and 1 on the pump. I have done that and it works. You need to use a two stage pump and it only turns one way , cw looking at the shaft. ( check) most motors are reversible make sure it turns the correct direction. The other option is face mounted . I have done this as well but the largest face mount, TEFC single phase motor I could find was 2hp I think. TEFC is totally enclosed fan cooled. You could us a drip proof but it will get junk in it. The gpm of the pump will set the hp of the motor.
In anycase 1 ph motors are limited to about 7hp $800 and 37 amps

I could go on forever. I run an 11 gpm pump with a 2 hp 3600 , 220 1ph, c face TEFC motor and a 3.5 id x 24 cylinder with a splitter valve. detented on the return. Works well and splits everything I stick in it. I am careful with big knotty ones , nibbling around the edges. I posted some pictures last year I think. They must be on my other PC cause they are not on this one.

 

[Scotty370]

I'd definately 'score ' about 6' of that "H" beam! That would give you room to mount a 4x24" ram with room for a wedge, push plate and tail mount. But I agree with KennyD and J_J, that your going to be disappointed with all your efforts if you don't kick up the power and volume enough to reward you for your efforts. I'd be looking for a 5HP engine, and a 11GPM 2-stage pump! I've been runnin' this combo for years, and am not disappointed! Welcome, and good luck, in the build, and your ME studies!! ~Scotty

 

[Diamondpilot]

I built a log splitter to run off my tractors hydro system. I built mine because I could not find what I wanted on the market. I have $450 in mine. Its really not much cheaper to build your own if you have to buy everything like I did.

I agree, a electric unit is going to leave you disappointed.

Here is a link to a bunch of home built splitters including mine. I will give you some good ideas.

http://www.tractorbynet.com/forums/build-yourself/157420-show-your-homemade-splitter-pics.html

Chris

 

[payton]

i have a dedicated 20A outlet in our garage right not for my compressor that I am planning to switch over to 220V sometime. i could run a 4hp (5hp not maxed out) motor off this. i keep reading that electric HP is 2.5 times gas HP is, so this means i have 10HP equivalent. is their anyway to mount a belt driven pump in a gmc jimmy?

Payton

 

[Wayne_H]

i have a dedicated 20A outlet in our garage right not for my compressor that I am planning to switch over to 220V sometime. i could run a 4hp (5hp not maxed out) motor off this. i keep reading that electric HP is 2.5 times gas HP is, so this means i have 10HP equivalent. is their anyway to mount a belt driven pump in a gmc jimmy?

Payton

Payton: Welcome aboard. A lot of great information here. That beam is a great beam. I'm puttting a splitter together now. The beam I am using is W8x40. It is a monster, but if you look around at the Rayco and Timberwolf Splitters you will see the big boys use that large beam. Three weeks from start to finish may be optimistic....

I wanted a cycle time of 11 seconds or less, and about 27 real tons, so I needed a 22 GPM pump, and with a 5" cylinder it requires over 10 HP. I'm using a 13 HP Honda.

There are also some good web sites to get parts. Look at http://www.splitez.com and give James a call. Super nice man with a lot of advice. They also build "real" splitters.

Since you are in school now, you might want to do some geometry and install a four way wedge and a log lift... My 4 way will have a 2"x4" cylinder, and the lift uses a 2"x10" cylinder.

Maybe think about an autocycle valve if you are doing a horizontal, and if horizontal think about making the top of the beam around 26-28 inches. The autocycle valve has two levers, you pull and forget. (might be bad if your finger was in the way)

Regarding electric being 2.5 the power of gas.... Not sure where you are in college, but where I went to high school they beat into me that one horse power was 746 watts. I've got a 5 HP motor on my compressor, and it is not five chinese horses... it runs off 220volts and draws over ten amps...

Good luck

Wayne

 

[Scotty370]

Good conversation! But, I question that an Electric Motor will out perform a Gasoline engine by a factor of 2.5? Just trying to learn here also! J_J could solve this....where are ya J_J? Plus, explain that 5HP , or 4HP not maxed out statement? ~Scotty

 

[payton]

Good conversation! But, I question that an Electric Motor will out perform a Gasoline engine by a factor of 2.5? Just trying to learn here also! J_J could solve this....where are ya J_J? Plus, explain that 5HP , or 4HP not maxed out statement? ~Scotty

on 220V 1 hp takes ~ 5amps. i have a 20 amp breaker so i will only be able to run a ~4hp motor. when an electric motor has less load on it it will draw less current. a 5hp motor maxed out would blow my breaker but a 5hp motor at ~80% load will not.

here is one example of a compressor driven by an electric and gas with the same output. 7.5hp electric. 13hp gas.
13 HP Honda, 30-Gal Gas Air Compressor
3 - 10 HP Air Compressors:

i under stand that 1 HP is ~750 W. but im not sure that a 1HP gas motor has 746W on the shaft. i don't really know anything about gas engines so i am just guessing.

 

[Scotty370]

Payton, again good education here.....Here's some 'food for thought' from one of my bandsaw mill groups. Looks like your 'right-on, about the 2.5 ratio.......~Scotty

http://www.woodweb.com/knowledge_base/Power_Comparison_Between.html

 

[MossRoad]

is their anyway to mount a belt driven pump in a gmc jimmy?

Payton

Yes. There are several companies that make hydraulic pumps that operate off of the belt drives of pickup trucks. They operate off of the belt and are turned off and on with a 12v electric clutch.

Here's a link to a bunch of hydraulic clutch pumps at Surplus Center.
https://www.surpluscenter.com/sort.asp?UID=2009120321382804&catname=hydraulic&keyword=HPCP

Here's a link to some at northern tool.
hydraulic pump clutch from Northern Tool + Equipment

Here's a link to some handy hydraulic calculators at Surplus Center.
Hydraulic

 

[BHD]

on small gas motors it usually takes about twice the HP rating on the gas to equal the electric

so a one hp electric would be close to a 2 to 3 hp gas and a 2 would be close to a 4 maybe a 5 hp,

on a generator, it takes a 8 hp gas motor to get 3500 watts out of it effectively,
(I know 750 watts is a HP, but there is wast in an eclectic motor and many times is closer to 800 to 900 watts, regardless, It can only produce about 4 HP electrically,

as one gets larger the spread is less,

another example, 4 hp gas and electric 1.1 hp
gas air compressor (similar specifications) DeWALT D55250 4 HP 4 Gallon Gas Hand Carry Air Compressor with Control Panel | ToolBarn.com DeWALT D55250
4 HP 4 Gallon Gas Hand Carry Air Compressor with Control Panel

DeWALT D55154 Heavy-Duty 1.1 HP Continuous 4 Gal Electric Wheeled Dolly-Style Air Compressor with Panel | ToolBarn.com
DeWALT D55154
Heavy-Duty 1.1 HP Continuous 4 Gal Electric Wheeled Dolly-Style Air Compressor with Panel
yes there is a little difference in the volume of air, but IT still shows the discrepancy in the HP ratings,

if the Hydraulic pump called for a 8 HP gas motor I would want to use min of 3 electric on it,

YOU may get by with a 2 hp if it was heavy frame motor, with a heavy duty cycle, and the surplus center pump, (it would most likely be a 220 volt set up)

Hydraulicstore.com - Call toll-free 877-778-3533 Mon-Fri 7:30-5:00 Sat 7:30-12:00 Central Time ___________
MTE Auto Hoist Power Unit • Motor is 2 HP 208/230 VAC. Runs at 3450 RPM • 2 GPM. Relief valve is set at 3000 psi. •

https://www.surpluscenter.com/item.asp?UID=2009120318291417&item=9-7503-8&catname=hydraulic
Minimum of 5 HP required for gas engine use.
Flow:
2 GPM HI press. stage
8 GPM LO press. stage

in my experience having a little extra HP is usually better than not having a enough,

 

[cycle_gator]

Just to weigh in here on the gas to electric horsepower disparity. Horsepower is horsepower, the ability to create work over time whether in a gas motor or an electirc motor. Where gas and electric motors differ is in their ability to create torque. An electirc motor creates instantaneous torque when voltage is applied. The torque curve (torque versus RPM) is flat, or nearly so, there are some small friction/heat losses as RPM builds, but essentailly they create the same amount of torque throughout their RPM range.

A gas motor, on the other hand, has a real torque curve with much less torque at idle, peaking at about 75% of rated rpm, then dropping off as RPM approaches rated capability, which, oddly enough, is where maximum horsepower is created and where the horsepower rating of a gas motor is obtained.

Now I am not sure about 2.5 to 1 disparity, but I do know that an electric motor of lesser horsepower rating can deliver the same work as gas motor of greater horsepower rating due to the differing realtionship between rated horsepwer and torque. Perhaps someone with an ME degree can lay out all the formulas and clarify the differences more precisely.

In the meantime, Payton, welcome to the forum and best of luck in your studies. By next quarter you will likely be teaching this class and filling us all in on thermodynamics and stoiciometric efficiency. Also good luck with the wood business. If I had owned the splitter I now have when I was in high school and early college trying to scratch out a few bucks selling firewood, I might still be doing it on the side.

 

[payton]

when you split with a gas motor is it running at max RPM? (when max HP is available) I see where the difference could in the face that maybe a gas engine only has half its rated HP at the rpm it is running at. again i don't know anything about gas powered splitters. does the speed max out on these?

Payton

 

[cycle_gator]

Payton:

That depends on the motor and where it is rated. Your splitter pump will have need of a particular RPM, whether direct drive, or with pulleys and belts, to achieve its rated capability.

In generators, if I remember correctly, a single pole unit must be run at 2200 rpm and a two pole at 1100 rpm. So, for many small gas motors they are running well below the RPM of their rated horsepower, but closer to their maximum torque. In terms of efficiency that is a great place for a motor to be, but it will not produce as much work over each unit of time.

I suggest you go about this by deciding the size of cylinder you want, then figure out how large a hyd. pump you need to operate that cylinder to its capability (remember a hyd. cylinder will move with almost any pressure and rate of flow, but it will not move fast and it will not develop much power with low pressure and flow.) Finally, figure out the size motor you need to run the pump. By the way, a 5 hp electric motor running on 220V will operate on a 20 AMP 220 breaker. 5 Hp requires around 18 amps, Each leg of the phase is carrying half the current, or about 9 amps. Just be sure, if you use some sort of extension cord from the outlet, the wire size is suitable to avoid signficant voltage drop or you will have heat and overload issues.

Have fun.

 

[payton]

Payton:

That depends on the motor and where it is rated. Your splitter pump will have need of a particular RPM, whether direct drive, or with pulleys and belts, to achieve its rated capability.

In generators, if I remember correctly, a single pole unit must be run at 2200 rpm and a two pole at 1100 rpm. So, for many small gas motors they are running well below the RPM of their rated horsepower, but closer to their maximum torque. In terms of efficiency that is a great place for a motor to be, but it will not produce as much work over each unit of time.

I suggest you go about this by deciding the size of cylinder you want, then figure out how large a hyd. pump you need to operate that cylinder to its capability (remember a hyd. cylinder will move with almost any pressure and rate of flow, but it will not move fast and it will not develop much power with low pressure and flow.) Finally, figure out the size motor you need to run the pump. By the way, a 5 hp electric motor running on 220V will operate on a 20 AMP 220 breaker. 5 Hp requires around 18 amps, Each leg of the phase is carrying half the current, or about 9 amps. Just be sure, if you use some sort of extension cord from the outlet, the wire size is suitable to avoid signficant voltage drop or you will have heat and overload issues.

Have fun.

I don't think a real 5hp motor will run on 18A 220V.
BALDOR L1410T MOTOR

that balador is over 20A. I know my 110V 2HP balador is 18A.

I am now thinking I will end up with a hydraulic pump on one of our suv's. might start with something small first though.

 

[Diamondpilot]

I don't think a real 5hp motor will run on 18A 220V.
BALDOR L1410T MOTOR

that balador is over 20A. I know my 110V 2HP balador is 18A.

I am now thinking I will end up with a hydraulic pump on one of our suv's. might start with something small first though.

I think in the end you will find it much cheaper to just buy a cheap Harbor Freight engine and a 2 stage pump. By the time you buy the pump, clutch, hoses, Quick Connects, ect you will have more money in it then a standard system. Remember engineering 101.. KISS!

Chris

 

[payton]

I think in the end you will find it much cheaper to just buy a cheap Harbor Freight engine and a 2 stage pump. By the time you buy the pump, clutch, hoses, Quick Connects, ect you will have more money in it then a standard system. Remember engineering 101.. KISS!

Chris

I am starting to see that it will be about the same price but i think that if i run a 20gpm @2500psi pump off a car engine that it will out preform a log splitter that does 20/6 by a long shot.

Payton

 

[BHD]

Payton:



In generators, if I remember correctly, a single pole unit must be run at 2200 rpm and a two pole at 1100 rpm. So, for many small gas motors they are running well below the RPM of their rated horsepower, but closer to their maximum torque. In terms of efficiency that is a great place for a motor to be, but it will not produce as much work over each unit of time.

not to side track the discussion, but the two pole generator is 3600 RPM, 4 pole is 1800 RPM and a 6 pole is 1200 rpm

most small generators run at the 3600 RPM rate, usually you need to get into the stationary units to get to the 1800, and some small diesels, there are some 6 and multi poled units out there but usually on larger commercial type units, or for special low RPM applications,
the RPM on a generator is what gives it the cycles on AC, so it has to run at a constant, (unless inverter technology is used)

~~~~~~~~~~~~~~~~~~~~~~~~~

there is different ways of rating horse power, and I do believe that is where some of the confusion comes in,

for an example there is the way tractors are rated, (Nebraska tractor tests) by draw bar horsepower,
(I have a old military 6x6 truck and it has a 90+ HP motor in it but draw bar power is less than 30 hp, from the manual)

look on any shop vacuum cleaner or electric air compressor nearly, with out fail they will run on a 15 amp circuit, but most likey there only pulling about 80% or the breaker would mostly trip, or about 12 amps,
but 15 amps at 115 volts, is 1725 watts, now divide that by, (750 watts, one hp with out wast) and the max with 100% efficiency is 2.3 HP,
which is most likely closer to 1.75 hp with the voltage drops and other frictions, but what is the sticker on the side of the machine, 4 hp 5 hp, it is not possible, (I am not saying in a locked rotor situation it may pull the equivalent of 4 to 5 hp of electricity, but it is not producing any where near 4 to 5 HP of usable power in that situation.

just like in automotive engines when there HP ratings are made it is with just the bare engine, no alternator, water pump, transmission, any other draw on it power and then it figured,
not a realistic rendering of the engine in the car,

ON small gas engines I figured it took about half of its power to keep it running, at the rated speed,

I know a HP is a HP, but there are ways of rating it to look like more than what is usable,