My firewood processor build

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muddstopper

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Well, its been a long time since I actually started this project. and I havent actually built anything yet, so no pictures. That is about to change, so I thought I would give a little history behind my thought process when it comes to building this processor. Plus, its raining outside and I'm bored

A few years ago, I was heating with all electric, had one of those Kerosun heaters for emergencies, but we seldom used it. Cold winter and a $300 power bill in Oct of that year and wifey decided to surprise me with a wood stove. My house has a basement and there used to be a wood stove installed, but the old stove was burnt out and I didnt want to use it. Took it out and threw it away back in 1999. Now my wife being the person she is had enough of those $300-400 power bills and thought a wood stove was the answer. Never mine the fact that I didnt have any firewood laying around, or any potential sources to get any. I had a saw and a truck and a axe so time to start scrounging. Made it thru the winter with green wood and power bill dropped to just over $100 and my wife was hooked. Wood stove means her a new pair of shoes or something, I dont know, but the stove was here to stay.

The next summer, I scrounged wood everywhere I could find it and rented a splitter to do the splitting. some of the wood i was getting just wasnt maul material, but it was wood. Next winter, some dry wood, but mostly green because i didnt like to rent the splitter unless I had a big stack of wood to workup. Went through simial the next summer and winter. and thats when I decided I needed a splitter.

I had a lot of junk laying around. I had bought a cylinder and control valve probably 20years ago to build a splitter with and had never gotten around to it. I wasnt burning wood so didnt really need it. I had used the cylinder to build a 6x10 dump trailer with. Well now I needed a splitter and the dump trailer was seldom used, so splitter build began. I have built a few splitters over the years and had rented a few so I had an ideal of what I wanted to build. I had a old Finn hydroseeder I had stopped using setting out back and it had a nearly new 25hp engine. I found a V20 Vickers vane pump in the scrap yard for $2. I had a 6x6 Hbeam in the scrap pile and a old boat trailer without a boat. So with pretty much everything on hand to put a decent splitter together, I started my build. I looked at the large splitter at Northerntool that had the adjustable height 4way wedge and knew I wanted to incorporate that in my design. Threw that thing together in a couple of weekend and life was good. Finally got ahead in my wood pile but then needed something to haul wood home.

That brings me back to my next splitter modification, I needed my dump trailer back working and I decided to buy a bigger cyl for the splitter. Northerntool had their 5in bore cyl on sale for around $249 or something and I thought nows the time to fix my dump trailer and soup up the splitter in one stroke. I installed the 5in cyl on the splitter and whoa, major slowdown in cycle times. I solved this by swapping out the pump for a 28gpm. Cycle times improved measureably and with the exta power I added a couple ore wedges and made it a 6way split instead of a 4way. at that point, splitting wood almost became fun. Big rounds, no problems, plenty of power and fast enough to make very short work of a big pile of rounds.

Enter processor ideal. Of course I had looked at every processor on youtube. I went to a couple of places that actually sold firewood and used processors and tried their machines out. I wasnt impressed, but it did beat running a chainsaw. I decided I wanted a bigger hydraulic chainsaw than what most of the manufacturers where using. The chainsaw seemed to be the biggest bottleneck on all the machines Iran and the ones I actually times on youtube. I didnt want a circle saw processor because of the size of wood I process. A circle saw big enough to buck a 30in dia round was too wickly expensive, not to mention all the extra expense of setting up the hydraulics to run one of those big blades. I figured I would build a Walstein style processor that uses the winch to pull the log onto the log trough and build a hydraulic chainsaw with power to block the wood and used my current splitter for the actual splitting.

Well then things took a turn, I found a hydraulic motor I think is capable of getting the job done for the saw, even got a spare for free. called CRD and got a sprocket, bar and chain and build the saw, but havent been able to test it out. It should work, math says it will, but you always have those nagging feelings about something untested.

I ran across a couple of conveyors for $200, so I bought them. Then gave up the ideal of the winch for feeding the logs. I still needed something to load the logs on the conveyor and thought, why not a knuckle boom, but I didnt want a big heavy knuckleboom. I splitting firewood, not handleing sawlogs. I wanted the knuckleboom mounted on the processor also. I ran across a A620 ditchwitch backhoe attachment for $300 and thought, with a little modification, a ready made knuckle boom, so I bought it. Then I found out it weighed over 3000lbs, Whoa way to heavy to be mounting on a processor. I sold the backhoe attachment for $800 and invested the money in some parts to build my own knuckleboom. I am using a 48000lb big truck axle tube and hub for the boom mount. I bought a #60 72tooth double sprocket and I will be using the agitator motor off the old hydroseeder to turn the boom. Aint built yet, but the parts are laying in the shop floor. well now my processor plans have really blew up from the add a winch to my wood splitter.

A member here had bought a cylinder off a guy that had several. I cant remember the members name, but he sent me a link to the ad the guy had on craigs list and I contacted him. The cyl have a 30in stroke, 4.5in bore and 2.5in rod, I wanted two, but shipping was higher than the asking price for the cylinders. Guy had 8 cyl and I could get all 8 shipped for about the same cost of shipping 2 so I bought all 8 of them. I sold 6 cylinders and kept 2 (and made $300) and will be using them to make my splitter. Well in order to have any decent cycle time using 2 cylinders, I need lots of oil. 60gpm should keep the splitter up with the saw so thats what I'm shooting for.

I have aquired a 8x8 hbeam, bought the metal for and built the pusherplate and slide. Found the metal to make the 12way box wedge, found a v70 control valve to handle the 60gpm of oil for the splitter. Found another valve to handle the 30gpm of oil for the saw. All that was freebies out of scrap bins. Paid $20 for a multispool control valve for the knuckle boom. Paid $75 for a 100gal hydraulic tank. Paid anothe $100 for 2 cylinder for the boom on the loader and today found a old forklift frame for mounting my adjustable 12way wedge for another $100. I I still have a few things to find/buy to complete this build. The biggie is a 170-190hp engine to pull the hydraulics, also need to buy a 3section pump for all the functions and the other biggie is going to be buying a rotator for the grapple on the loader.

So I have been scrounging and gathering parts for this build now for about 5 years and its getting down to the nitty gritty. I finally have enough parts to actually start putting some of this junk together. Unless i get really lucky and someone gives me an engine to power this thing with, it probably wont be completed this year, but I plan on having it built waiting on that engine to fall in my lap. I figured it up the other day and after the buying and selling, I am out of pocket about $1400 in this build at this point. Engine and hydraulic hoses are my last major expenses, as well as a rotator if I have to buy a new one, but I am shooting for keeping this processor build around $5000.
 
I had to do a lot of serious thinking when it came to building the chainsaw. I had ran a few processors and simply didnt like the speed at which they where able to buck a round. One thing I saw in common with the machines I ran was the type of hydraulic motor they where using. Basicly what the manufacturers where using where gear motors. To get the speed they needed for a chainsaw, they overflowed the oil. Meaning they had a hydraulic motor rated for a certain flow and speed and they threw more oil at it to get it to run faster. I dont know if overflowing the oil is a issue in this application, but it certainly did seem like it should cause a maintenance issue with that approach. Chain speed wasnt the only issue I observed with those factory saw. Lack of power is another. Every hydraulic chainsaw I operated it was very easy to bog the saw where you had to lift the bar and let the saw rev back up before completeing the cut. And this was sawing what i consider small wood. I knew the wood I would be processing was going to be much larger than the capabilities of those machines, and what I was seeing just wasnt acceptable.

I did some thinking about how much saw I wanted and decided a Husquvarnia 3120 was about a badass a saw as you could buy. Uses a .404 chain instead of a 3/8 as well. I decided to try and match the chain speed and power of that saw. Yea, a 395xp will probably cut faster than the 3120, but you say tomato and I say tomatoe, whatever. Anyways, a 3120 saw has 8.4hp, turns 9000rpms and makes 7.7nm of torque. Chain speed is 87.6 ftsec. I figured if i could match those numbers I should have a hydraulic saw that would out perform the ones I had ran on other machines.

Now everybody concerns themself with rpms to get their chain speed, and it is one factor, but not the deciding factor. Pitch of chain and number of teeth on the sprocket can make a big difference in how fast the chain will run around the bar. Gas powered chainsaws have little crank shaft dia and use little bitty sprockets, which is why they have to turn 9grand to get the saws to cut. Take a slower motor and a larger sprocket and you can get the same ftsec of chain speed as you would if your motor turned 9000rpm. If you look at the f11 motors, they turn massive rpms and cut very fast but they have their drawback. It takes around 5000psi of hydraulic pressure to get that fast cut. Gear motors cant turn the rpms of the f11/f12 motors but they will make as much torque with less hyd pressure. I choose to use a radial piston motor. A radial pistion motor will turn more rpms than a gear motor without having to overflow the oil to get there. A radial piston motor will create more torque than a f11 style motor without needing the expensive high pressure hydraulic system to get there. Match hydraulic motor size to proper oil flow and pressure, choose the right size sprocket and its pretty easy to match chain speed of a 3120 chainsaw, with the added benefit of more hp and torque. I choose a 1.3cuin hyd motor and will run 25gpm @3000psi of oil thru the motor to get around 4440 rpms. wth a 13tooth sprocket and .404 chain and I should have 5 times the torque and up to 4 times the hp of a 3120 chainsaw and a chain speed almost similar to the same 3120 chainsaw. I dont plan on running the saw with 34 hp and 3000psi. I will start my pressures at around 700psi and work up from there. I should still have around 11hp at the saw which is still more than the 3120. Saw should cut, but My theories havent been tested yet.
 
Subscribing. Looking forward to this build. I suspect that as you work up to full pressure you'll be able to drop rakers and eat through the log and not care about chain speed.
 
Is 30" the max diameter you are building for? Do you see much wood over that and just not really enough to justify designing to handle bigger? If you see 30"+ wood, will you be bucking and noodling by hand, adding a splitting cone to the boom to split the bigger logs down to smaller sizes, or?

What size are the splits going to end up with the 12-way box wedge? Say a 30"round goes in there - will any of the splits need re-splitting and if so, are you having to manually separate those out before they go up the conveyor or is there some sort of grill shooting those off to the side or?

How are you handing the inevitable scraps and trash? Going to filter that straight off the wedge, off the top of the conveyor, both, neither, or?

How are you oiling the bar - bleeding a wee bit of hydraulic fluid or pumping bar oil and if the latter how are you controlling the rate and on/off?

Really looking forward to this build thread.
 
Muddstopper. What racial piston motors are you looking at. I am wanting to build a saw also I have the same concerns on using a regular hyd motor. I just priced a sunfab scm12 and scm17 motors. $1,000 and $1,500. I am thinking strongly thinking about belt drive and a electric clutch on a smaller two cylinder motor cut the cost on the engine and hyd components. If you are going to used a big diesel engine look at combine engines they seem to be the best value in our area.
 
What processors did you try out that did this "Every hydraulic chainsaw I operated it was very easy to bog the saw where you had to lift the bar and let the saw rev back up before completeing the cut. And this was sawing what i consider small wood."?

I've run several machines and never had that happen. The only time I have to fight mine is when the chain is dull.

With the rest of the "holy cow overkill" why not 11H bar/chain? (.75" .122 harvester)
 
Well, just got home. After starting this thread, I got called out to work a major trail derailment in Sc. Went 60hrs straight with only 2 hrs rest. Enough to make one think about retirement.

Well after reading thru the questions, I will continue.
The question was asked, about the 30 dia size. While I get plenty of wood over 30in dia, most of the wood is under 2ft dia stuff. My saw bar is only 27in long. I have a pretty good splitter already that will handle what really big wood I get, and I had to draw the line somewhere when it comes to size to process. Any wood larger than 24in dia will most likely have to be resplit, even after going thru a 12way wedge, so I will just keep my current splitter handy for the big wood.

Scraps and trash will go into my shop stove, it a barrel stove and doesnt care what I burn in it.

My oiler will be a electric pump. I plan on a micro switch that activates the pump whenever the saw control valve is activated. I might have to do a little trial and error until I get the oil flow just right, but using a electric pump and a needle valve should work.

I know I said radial piston motor, big goof on my part, I meant axial piston motor. The axial 7piston motor I am using is a Poclain simlar to this one, but bigger, http://www.poclain-hydraulics.com/en/products/motors/m-mv/m1. My motor is s specialty motor spec'ed out a little different, but basicly the same.

The brandname processors I have tried are Blockbuster and Builtrite. Didnt think much of either machine. Both machines would process wood, but both machines where just to slow for my liking. Not saying either machine is bad, or a wrong choice, for someone wanting a cheap processor, but neither machine met my expectations of what I wanted from a processor. I just hope what I am putting together doesnt disappoint me as much as those machines did.

As for not using a 3/4 bar and chain, if i had found a used buck saw reasonable, I would have. When I started this project, I wasnt planning on a 190hp diesel engine to run everything and I bought the .404 bar and chain to go with my plans at the time. I was going to use a 50hp izsusu engine and a single 5inch cylinder for the splitter. Run the splitter and saw off a single 28gpm 2 stage pump. My plans kind of changed according to parts I accumalated while scrounging. If I run across a cheap buck saw in the near future, its still possible I might go that route.
 
I guess it will interesting to see the cycle and speed times. Faster is not away "gooder" as there will always be a bottleneck point.

We have 2 Blockbuster processors at the shop and have had no complaints. They are well built, quick, and very good on fuel.
Generally burn about a gallon to a cord. The older machine is an 18-20 with over 7000hrs.

A couple other guys I know run big hp engines on processor. Not a whole lot quicker "real world" but burn 5-7 gals a cord.
 
I guess it will interesting to see the cycle and speed times. Faster is not away "gooder" as there will always be a bottleneck point.

We have 2 Blockbuster processors at the shop and have had no complaints. They are well built, quick, and very good on fuel.
Generally burn about a gallon to a cord. The older machine is an 18-20 with over 7000hrs.

A couple other guys I know run big hp engines on processor. Not a whole lot quicker "real world" but burn 5-7 gals a cord.
When it comes to speed, I think a lot has to do with the operator. Even the best of operators cant be fast if the saw cant keep up with the splitter or the splitter cant keep up with the saw. Cords per hr also has a lot to do with the size of the wood being split. With enough power, the splitter doesnt care if the round is 2 ft thru or 6 inches. It takes the cyl the same amount of time to run in and out either way. Difference in time would be measured in nano seconds, but 2ft dia wood will produce a lot more cords of split wood in a given amount of time than 6in dia wood. Every thing but the biggest of processors usually limit round size to about 20in dia. Sawing small dia wood takes a lot less time than sawing big rounds also. I am making mine capable of 27in dia rounds, but I also know that a lot of what I get will be much smaller. I have taken measurements of log sizes that I get for a while now and feel 27in dia will take care of the largest majority of my wood. Anything bigger than 27in dia will go thru my regular splitter.
 
mudstopper I might be able to help with the hyd plumbing, Its what I do I am a mechanic for a car hauler, I do most of our hyd work, repair to re-plumb. Any idea on what you need for hyd hoses? I pretty much only use parker I feel that they offer the best stuff for the most part.
 
I havent even started thinking about hoses yet. I have a pretty large assortment of various size hoses laying around, probably not what I will need. I am considering using a lot of steel tube for the long runs, but is hard to come up with a blueprint of hoses needed when your building with plans kept in my head. I'll keep you in mind tho when the time comes. I will say, that the saw will most likely be #12jic hoses and the splitter cyl has 1" ports so most likely #16jic. Control valve is a Parker v70 and I think the ports are 1-1/4 but havent measured them.
 
Building the hydraulic saw,
The saw mount is made out of 3/4 plate. I cut the hole for the hyd motor using a bimetal hole saw. I then drilled and taped the mount for studs to bolt the bar to. I marked where the oil hole was in the bar on the bar mount and drilled and taped for a 1/8 pipe fitting to attach my oiler hose to. The round rod sticking out the side will be drilled and taped to make a chain tensioner with. It will need a little fine tuning once mounted and hooked up, but for now it will do.
 

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A few pics of some of the other parts I have been working on.
I pile of steel fo the 12way wedge. I trimmed them on a 20degree edge using my home made track torch and then used a cup wheel on a grinder to get them sharp.
One pic is of the rear cyl mounts for the twin splitting cylinders. The pins are 2.5in dia and I used a hole saw to cut the holes.
The pic with the sprocket is the base for my knuckle boom. The hub is a 48000lb truck hub and the sprocket is a 72 tooth, double #60 and will be turned using a stator rotor hyd motor.
The pusher plate is all 1inch metal. It is 27in wide and 20in tall. The base slide is 12in wide and made to fit a 8in Hbeam. The beam will be plated on the top and sides, but I havent gotten around to that yet.
 

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Some of the hydraulics,
The big control valve is a parker, V70, air over hydraulic. Capable of flowing 70gpm. I plan on a air foot pedal to control the splitter cylinder, but it does have a hand lever if needed. The Yellow cyl are 4.5in bore, 2.5in rod and 30in stroke. Thes should yeild around 53tons at 3000psi of splitting power.

The next pic is of a 10 spool control valve I am considering for the knuckle boom. I have another valve off a backhoe I can use for the boom, and it has joysticks, so I aint sure which setup I will use yet. Leaning toward the joysticks.

The blue solenoid valve is a single acting valve for Rexroth. It will flow 30gpm and is what I plan on using for the saw motor.

Next pic is of a hyd oil cooler, rated for 250psi and will most likely be plumbed into the saw motor circuit on the return.

Last pics of the black cylinders are for the root and dipper boom for the loader. They are 3.5in bore, with a 24in stroke. I almost pulled my hair out trying to figure out the mounting points on the base and loader to make these cylinders work.
 

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You mentioned wanting to be able to cut 27" across logs. What length is that bar?
 
a couple of more pics of scrounging scores.
First is a set of log bunks made of 4x4x1/4 tube. I plan on using part of the bunks for the knuckleboom as the root and dipper booms. I will use the rest of it for building the outriggers. Normally i would think this material to be a little light for use loading logs, but I am planning on loading firewood, not saw logs.

The other thing is actually a forklift mast. I will be using it to build the slide box frame to hold my adjustable 12way blades.

The trailer is one I build several years ago and is what I plan on mounting the processor onto. It is made of 4x4 channel and is double framed, 18ft bed, with two 3500lb axles. rated for 7000lbs. I plan on weighing the entire rig once built and will be changing out the axles if needed.
 

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