Buzz asks: How to build a skidder?

[Buzz-sawyer]

I have been collecting stuff to build this thing and may actually end up doing it. 8) 8)
Anybody interested in this kind of project? ???

I am planning on using 2 ,2 way cylinders to articulate with a single lever/joy stick

The wheels are off f gleaner combine so 28" (I think) i am cutting out the chevy truck rims and welding them into the combine steel.....the two ton rear ends are 2 speed types off 1968 chevy grain trucks, I will look around the net for ratios. Does anyone happen to know off hand??

I have several gas and diesel motors to power the pump...I am a little unclear on calculating what would be needed in a pump to power this rig.............I also want to use the hydaulic power to break(slow)

[sprucebunny]

What's going to drive the wheels? Four wheel drive?

[Buzz-sawyer]

The components are 1) 2 chevy 2 ton truck frames and rear ends

                              2)  4 combine tires bought at auction

                                3) 2 hydraulic motors to direct drive rear  

                                     ends/ provide breaking

                                 4)international diesel power plant

                                  5) large hydraulic pump

Now , what do ya think, what do I need as far as drive motors and the primary pump?

I would rather under power the rear ends so I bog before a breaking point.....

[J_T]

Buzz thare is a book out on homade equepment .I forget the name of it . I beleive those 20' wheels will weld right in. Had though of using a hydro rear from an old combine and run it with a pump.Also though of an old 4x4 two ton truck then weld those rims on it and bend it in the center.I know a man put a control like you said on his factory skidder as their parts were to high . 8) If I had enough parts I would done built one.

[J_T]

Buzz my neighbor has some hyd pumps . Don't know how big they are one has a 20hp 3ph motor on it he also has hyd tanks too.I would put a pressure by pass on them motors or give it a study at least.

[Buzz-sawyer]

JT ...................Man I need that Dang name........ ;)
I have heard a few people mention all the good ideas in farm show magazine???
I need to get the hydraulic sizing right on this beast

[Paschale]

Hey Buzz,

You ever heard of Junk Yard Wars on the Discovery Channel?  That's a very cool show--I think you'd fit right in there!   ;)  You've got more ambition than me!

Let us know how she turns out...

[sprucebunny]

It's a good thing I don't know how to weld.I'd have a yard full of contraptions instead of a yard full of beat trucks. I've thought about hydraulic drive things alot but don't know much.
How do you drive a regular rear end with hydraulics? The opposite of a PTO?

[Buzz-sawyer]

Spruce
It is really simple, a hydraulic ( :)high torque/low speed) motor has a shaft comming out and you simply hook it to the input shaft of the read end.....

[slowzuki]

www.machinebuilders.net is a good place for info!

[Buzz-sawyer]

I think so too zuki....... Actually,
they are, as to project building, as forestry forum is to milling...the best on entire net  8) 8)
And I need all the help I can get.... ;)

[redpowerd]

id like to make something like that, but a bit smaller. like with 1ton x's and a 4cyl contenental, i dont need it to tow a large amout of large logs, just a small amount, plus i have a pair of corperate 14 bolts laying around doing nothing. hydraulic is a very wise idear, brakes, steering, and drive all in one. kinda. how big is the pump and the motors, has that been established yet?
why are you using such big x's?

[Bruce_A]

Slowzuki; you have to have a streak of pure meanness or you are nuts.  I can't get enough sleep now trying to read all the neat stuff on this forum and then you have to add another to my favorites list.  Industrial hydraulics manual by Vickers may give you the specs you need for your motors and pump.  All else fails, find someone junking an old excavator for pumps and drive motors and good luck.

[Fla._Deadheader]

 Buzz, yer NUTZ. Absolute, bony fied NUTZ.  My kinda guy  ;D ;D ;D

  Good thing we don't live near each other. Between us, we would probably revolutionize somebodys Industry.  ;) ;) :D :D :D

[Buzz-sawyer]

Did i mention its methane powered ;)

[karl]

I usta own a Ford 9030 Bidirectional tractor that was built a lot like you are designing. It had one (big) pump and hydrostatic drive to regular X's. don't have the manual anymore either, but maybe a tractor mechanic  could find the info.
Tires on the beast were 16.9-28, no clue as to the ratio.
It was 105Hp but you wouldn't need more than 60 I wouldn't think.
Seems like I 'member Surplus Center catalog having formulas for HP,pumps,and motors. They've gotta website.

Good Luck with  the Buzzskidda

[Buzz-sawyer]

Karl
Do you recall what kinda center pivot that ford had? :

[

[Buzz-sawyer]

Redpower
I have a set of 1 ton axels, but they look like tooth picks......I figure asking automotive equipment to do this kinda work it is best to over size......also I want some weight to it so it can work(push) with a blade

[Murf]

Buzz, get the BIG truck warmed up.......

Sitting in the yard is not just the log loader, but what's left of a mid-sized excavator, no motor, but the pump, bell housing and drive motors are all there.

Should I just work you out a price by the ton ??   :D

[Buzz-sawyer]

I like tonnage pricing. ;).He who has the biggest PILE wins

[Murf]

I thought it was he who has the biggest pile STANDS UP  :D

[karl]

Buzz-
Pivot was like two big ole hinges(big- maybe 2" thick plates with a 1 1/2-2" pin through) one above the driveshaft/pto shafts and one below.
The front and rear frames were only able to pivot side to side- the rear axle was hung on a pivot to allow tires to follow the terrain. you could jack one wheel up prob'ly 10-12 inches. There were many times that there were only 3 tires on the ground. really should have more twistability for a skidder.
It had locking diff's- I would much rather be able to brake one wheel on each X to aid control on side hills and turns- taken a couple of interesting sideways rides with all four turning. It can get real frustrating when all you can do is go back and forth in the same ruts, or further down the hill.

[theonlybull]

buzz, what's the hp rating on the motor your gonna use?  
say it's 70 hp, i would look at about a 50 gallon variable displacement pump, to run 2 motors that require 25 gallons each.  make sure the pumps a through shaft pump, or has a  charge pump on it to run your steering cyl, blade, and i assume a hyd winch.  

the varriable pump, although more expensive, will give you much better control.  this will have to be a closed system, with case drains going back to your resivour, and make up oil supplied by the charge pump.  you should be able to put inline pressure relief's that will prevent you from damaging the machine.  these are adjustable, and are much more reliable then "bogging" the motor.

i think our skidder is steered with one 3" cylinder.

as for piviot. you'll wan 2 ears on one half, and 4 on the other. this will give you a good tight center, that will last a long time.
as for articulation. i would simply put a couple ears on top of the rearend, and run a pair of tubes to the front of the machine with another set of ears.  then plate this area in to give you a good skid plate.  i think you can see  what we have in the pics of our machine.

i caution who ever plans to use 1 ton truck axles, i think you will find them way too weak for forrestry use, unless your only gonna use the 16" wheels and truck tires, which won't work very good in the woods.

[Buzz-sawyer]

Hey thanks for da input
I would like to use a little diesel (perkins) 4 banger.
If I was to gear it down through two trannys it would do the stuff......but I am not sure if it will cut the mustard with 50 gpm hydro pump????

     You said  ,"the varriable pump, although more expensive, will give you much better control.  this will have to be a closed system, with case drains going back to your resivour, and make up oil supplied by the charge pump.  you should be able to put inline pressure relief's that will prevent you from damaging the machine.  these are adjustable, and are much more reliable then "bogging" the motor"


5.44 CU IN EATON VARIABLE HYDROSTATIC PUMP

     I find this interesting, I am un educated in the variable pump, and motive power applications.......so this is good food for thought. ;)


as for piviot. you'll wan 2 ears on one half, and 4 on the other. this will give you a good tight center, that will last a long time
Do ya have a pic of this.. ???

 ???

[Buzz-sawyer]

Ifound this.......25 gpm reversible motor

15.36 cu in DANFOSS 151B2082 HYD MOTOR