Home made sawmill mods.

[Clover]

I'm doing some changes to my mill and I thought I'd share them with the forum.
To give some background info I built the mill about 9 or 10 years ago. I ran it for about 20 hours then did some major mods to it and ran it for another 20 before basically abandoning it until this winter.
It's got a 13hp hydraulic power pack and a 30 hp Kohler engine. I've almost got 90 hours on it now and I'm doing some more upgrades. The drive pully is 3" and the driven is 12 with a 21" trailer tire for the wheels. The band speed is a bit lower than recommend and that 3" pully makes it hard to properly tension two B belts. So I've ordered a 5" driver and a 16" driven pully set to help out in that speed and tension department.
I'm also putting hydraulics to raise and lower the head and tension the motor. I will also have a switch that will run a solenoid for the throttle and turn the lube off and on.
This will make the machine much faster as I'm using a winch currently and it can be aggravating to set the proper cut on the log scales. It's also slower and I need to shut the blade down manually.
Here are a few pictures to start one is of the old handle to engage the belts and the others are of the hydraulic cylinder to tension the belts.
Tomorrow I install the solenoid for the throttle.



Sorry if they are not upright tomorrow I will remember to hold the phone correctly

[gww]

Cool, more pictures tomorrow.
Cheers
gww

[Clover]

I've got a few more things done to the mill. My new drive pulleys are on and also the new throttle solenoid installed. Removed the winch that was used to raise and lower the head and started to mock up the new bearing locations for the lift chains and hydraulic motor. 

Old throttle

New solenoid

New pulleys


Old winch

New bearing block

[Clover]

Since I'm going to be able to get more tension on my pulleys I've been thinking about that upgrade that woodmizer has. It's the flange bearing that mounts on the engine to take some stress off of the motor crank shaft and bushings. Does woodmizer make one for the Kohler engine? It would be easier than making one and quicker as I'm making everything else up. I'm a bit concerned about loosing my engine to bearing failure and the work and cost to repair it.

[Rougespear]

May I ask what you used for a throttle-up solenoid?  I am thinking of a similar mod... I can't tell from your pictures the setup.  Thanks, and you'll be very happy with the new chain lift you are fabbing.

[Clover]

It's a Kohler throttle solenoid made for the 18 to 25 hp engines. Mine is the 30 but I think it's just a little bigger carb. It went on just fine. It took a couple hours as I've never done one before and the instructions were not worth the paper they were written on. Messing with governors can screw up an engine fast so I was extra carful. I also trimmed the bracket with a zip wheel as the governor arm hit it. The instructions said to bend the arm but it would not have worked as I saw it. All my parts are done to start the chain lift so I will have more pictures tomorrow.
I'll see if I can find the part number for the solenoid 

[DDW_OR]

FYI here is a link to some useful mods

http://www.forestryforum.com/board/index.php/topic,7789.msg1397352/topicseen.html#msg1397352

[Clover]

Made some more progress today. Lots of drilling and tapping I'm not welding anything on. Those cordless drills can almost rip your hand off drilling into quarter inch steel.
This is the lower idler/takeup sprockets and brackets.

This is the hydraulic motor and drive shaft for the #60 chain lifts.

[Clover]

Hopefully my calculations for the head speed is correct. I'm actually worried it will be to slow.
I will also be changing the final drive sprocket for the head carriage travel speed. It's currently a 19 tooth sprocket I'm going to 22 to speed up the return rate.

[DDW_OR]

put a flow control on the feed to the feed motor

Left lever is carriage movement.
first rotate flow control (Feed speed) to zero, then push lever left lever all the way forward, now rotate the flow control to move the carriage forward.
when the cut is complete leave the flow control where it is pull the left lever to move the carriage back to the start location

 

  

[Clover]

Thanks for the pictures DDW. How is the flow control plumbed? I've got a flow control on my mill but it will slow the flow of oil in both directions. I was going to just remove it as it is always wide open and I just feather the control valve to get the best cutting speed. On the return I pull back all the way.

[Clover]

More progress today. Tomorrow I'm going to pick up my hydraulic hoses. This is going to hurt, four hoses at 64' each. I still need to wire in my solenoid and lube pump to a switch and solenoid setup. I'm going to also wire in a master off switch. I need the solenoid switch to be spring loaded so if I go to far with the hydraulic cylinder to declutch the motor it won't get damaged.

[Clover]

Once I'm done this upgrade I'll start putting together parts for a chain turner. I have a claw turner/clamp now but having that extra "hand" on the mill will make life that much easier. It's either that or a set of two plane clamps.

[thecfarm]

Clover,you are a busy guy
Hey can I help you out with the pictures?? 

 


 

 


 

 


Notice the "white" space between the pictures that I posted? I hit the enter key 3 times to bring the picture down and leave some white space,than I hit the Preview key to make sure it looked good.
Not being picky,just easier to look at. 

[Ga Mtn Man]

Clover,you are a busy guy
Hey can I help you out with the pictures?? 

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Notice the "white" space between the pictures that I posted? I hit the enter key 3 times to bring the picture down and leave some white space,than I hit the Preview key to make sure it looked good.
Not being picky,just easier to look at. 

I was going to offer the same suggestion.  Thanks for being the "bad guy",  thecfarm.   

Really enjoying following your re-build, Clover.

[Clover]

That's much better c-farm, no bad guys here . I noticed yesterday that if I didn't leave a comment between each photo that they become very hard to look at.

Nothing better than learning something new everyday 

[Rougespear]

Clover: how are you addressing downward creep of the hyd motor?  In similar setups to yours, I have seen a 30:1 gearbox used to help hold the weight of the head from creeping downward.  Even in a closed circuit, there can minute amounts of oil weeping past seals and such that may allow the height to fall... just a thought.  I really like your setup!

[york]

I agree,should use an right angle drive,with an 30 to 1 ratio-that is what cook uses on there mills,theirs is made by Cleveland ...When your oil get hot,you will get saw head creep...Your setup now look`s too fast...Reason i know the ratio,i have the Cleveland rt/angle gear drive..

[Clover]

Thanks for the input gentlemen. I'm not one to try and reinvent the wheel, but when it comes to hydraulics I do have a working understanding of them.

Right angle drives do have some advantages as they allow you to eliminate the chain drive at the motor and to also use a smaller less powerful motor to raise the head. They also remove all side load on a motor. Most smaller high speed motors can't take any side load, mine is capable of high side loads at low rpm's.  A hydraulic motor turning 750 rpm's will only be turning 25 rpm's with a 30-1 gear reducer. My motor is 23.3 cubic inches. With my power pack that works out to 25 rpm's (if my memory is correct) with a further reduction at the final chain drive. This will be VERY powerful and have plenty of holding power. As for creep that's anyone's guess until it's actually in operation. I'm not thinking it's going to be a big problem for a 15-20 second cut. In the event it is I will add in a pilot check valve. The description follows

"Use to lock a hydraulic cylinder in one direction. It will hold up a load and prevent it from drifting down. Also prevents the load from falling if a hose fails. Place in between the directional control valve and cylinder. When the control valve is in neutral and the check closes the cylinder will be locked in position."

As for speed the directional valves also work as flow control allowing me to send a little or a lot of oil to control the travel speed.

I hope this clears my madness up a little. I'm not one to slap parts together and hope for the best. It's usually a few hours thinking stuff through to get it right the first time.

[ljohnsaw]

...In the event it is I will add in a pilot check valve. The description follows

"Use to lock a hydraulic cylinder in one direction. It will hold up a load and prevent it from drifting down. Also prevents the load from falling if a hose fails. Place in between the directional control valve and cylinder. When the control valve is in neutral and the check closes the cylinder will be locked in position."

So how does this pilot check valve allow you to actually lower the head when you want to?  Does it have an internal relief valve so when you have high pressure it allows it to pass?  Really curious about that.

Also, depending on how you are "inserting" your pictures...  If you use the "Insert image into post" button way at the bottom of the Gallery view page, you will get an automatic two html Break characters < br > at the beginning and I usually delete the first one to save space on my posting.

[Clover]

Yes it does have an internal check valve. Depending on the type or model the pressure it takes to overcome the check is different and or adjustable. They also have the benefit of not allowing a hydraulic motor to drop when opening a valve and the pressure and flow is to low.

Having a working knowledge doesn't mean I'm a hydraulic specialist . I still get nervous I've got it right until that second it's actually in operation.

[Kbeitz]

Here is some info on one.

http://www.princehyd.com/Products/Hydraulic-Valves/Flow-Control/Model-RD1400

[Clover]

Thanks kbeitz. I was thinking of a single valve pilot just on the lowering side of the motor. They are a lot cheaper 

[Kbeitz]

Thanks kbeitz. I was thinking of a single valve pilot just on the lowering side of the motor. They are a lot cheaper 

Could be hard on things if you forget to open it.

[Clover]

It opens automatically with the opening of the spool valve. You don't even know it's there it just holds the load in place until it hits a preset presure. The one I'm looking at, if I even need it, is preset at 75 psi to release.

[Clover]

Did some more research on the pilot valve and I'm not sure it would work in this situation. Basically what would happen is if a pilot valve opened at 75 psi but once the motor started to move the pressure would drop and the valve would close. It would chatter in a sense. Say I'm trying to slightly lower the head the pressure would not be high enough to hold the valve open so it would open and shut very quickly and chatter. I'm going to have to put some more thought into this for sure.

[Joe Hillmann]

Did some more research on the pilot valve and I'm not sure it would work in this situation. Basically what would happen is if a pilot valve opened at 75 psi but once the motor started to move the pressure would drop and the valve would close. It would chatter in a sense. Say I'm trying to slightly lower the head the pressure would not be high enough to hold the valve open so it would open and shut very quickly and chatter. I'm going to have to put some more thought into this for sure.

What about skipping the hydraulic motor all together, keeping the chain and sprocket and bar across the top to keep everything tied together and just using a hydraulic ram on one side with the pilot valve in it?

[Rougespear]

I saw a manufacturer do just that, use a hyd ram that simply pulled on the chain... but you already have the hyd motor.  My opinion: test and see how if works just how you have it.  If you find you have problematic creep, it would not be difficult to incorporate a 30:1 gearbox into the design in the future.

[Clover]

There are many ways to get this head moving up and down. I thought about using a cylinder but it also presents different challenges to make it work well. The pilot valve would do the same thing with a cylinder. As it requires next to no pressure to lower a heavy weight we'd be back in the same situation with the pilot valve opening and closing. To be honest I don't see the drifting to be much of a problem. I've got another taper roller at the end of my log bed that I don't use. After running the hydraulics for 5-6 hours it will drift open about a half of an inch. That works out to 0.000462962962963 inches of movement in 20 seconds. I would think I would need to be more concerned with the actual log moving more than the head dropping. It is all trial and error thought until it's been done at least once

[Clover]

Had a test run with the added hydraulics today. After bleeding the auto clutch hydraulic cylinder it worked nice and smooth. The head raise and lower speed is almost perfect just a tad on the slow side for me but ten times faster than the winch I had before. Any faster it probably wouldn't be practical for a home made mill though. As for head creep I marked the mill with the head suspended and I am getting a bit after a minute. Not enough to bother in a cut but if I set my height and got sidetracked for a few seconds before cutting it would effect it. But that's not the biggest problem. When the hydraulics are turned off and you open the spool valve it won't lower slowly it'll come crashing down. Ask me how I know  . So tomorrow I'm going to pick up my new double pilot valve. I'm more concerned about safety than anything else. Someone could be seriously hurt if that thing crashes because I forgot to lower it before powering down.
Did I mention how much a pain it is to run four lengths of 64' hydraulics hose to a head and suspended cable.

[DDW_OR]

Thanks for the pictures DDW. How is the flow control plumbed? I've got a flow control on my mill but it will slow the flow of oil in both directions. I was going to just remove it as it is always wide open and I just feather the control valve to get the best cutting speed. On the return I pull back all the way.

 

 

the speed control looks like it was custom made for Timberking
 

  

I use and old wheelchair as a tool cart. I just put a large cardboard box in the seat and go.


 

[DDW_OR]

There are many ways to get this head moving up and down.........

TK uses two chains, two gears on a shaft and a Hydraulic motor

FYI - this photo is for the carriage movement forward/back, but you get the idea
 

 

[Clover]

DDW why do they have the carriage forward and reverse motor at the top of the head? 

[Clover]

I got a few more things done on the mill. It's been blowing and snd snowing like crazy the last few days so it's been a bit slow. I had to make up my switch plate for energizing my idle solenoid and my lube pump. I'm using a relay off of the switch so when the switch is on it powers my solenoid and when off the relay powers my pump. (87 and 87a on the relay). The switch will slide back on a spring loaded plate if I over do it with the declutching hydraulic cylinder. I thought about an electric clutch but couldn't find one with enough power. It does look like TK uses them. Anyone have information on them?

[Clover]

Sometimes I'm that moth that keeps flying into the porch light, ain't too smart. Well I was warned and didn't listen. Soooo.... Now I'm installing a right angle 30-1 gear box at the head of the mill. It was still dropping from internal leakage by about an 8th of an inch over a minute. The only way to hold that head with a hydraulic motor alone is to get one with an internal brake mechanism and I don't even want to ask how much. It's not a complete bust as it will be about 500 cheaper as I've already got a small displacement hyd motor and just a small modification to the mount. I can return the motor and pilot valve that I had bought and the gear box was less than a quarter of those. Hopefully tomorrow I'll be back cutting as logs are building up.

[Magicman]

I am hoping that your new gearbox has a worm gear.

[Clover]

Definitely a worm gear MM. Once burned twice shy kinda thing. There is a reason sawmill companies do it that way  so will I . Just kinda like pullin the blade through a cut (no I didn't make that mistake)

[Rougespear]

Right on Clover... I'm happy to hear you're going this direction.  If it means anything: if I every redo my head lift, I will be changing from the ACME thread to a 30:1 gearbox... I think you made a wise decision.

[york]

Yes,smart move-your lift chain,what # is it 40 or 50 ?? Will be interesting to see how you mount the HYD. motor to the Gear reducer...

[Clover]

York the lift and drive chains are 60. The drive from the hydraulic motor is 40. My head is super heavy. Lots of steel, the motor plate is 1/2" plate and lots of 3x3" tube for my wheel mounts.

I worked on the mill for about 6 hours today and got the new gearbox and hyd motor mounted. The first test lift was an excellent success. If I didn't already have the hydraulic motor I would have gotten one a little bigger (displacement) and did a different chain drive ratio but it does work properly now and doesn't drift down.

[gww]

Clover
Yea baby!
Cheers
gww

[Ga Mtn Man]

That looks very heavy-duty Clover.  Nice work.  How'd you cut the slots in the mounting plates?

[Clover]

I first welded the plates together then laid everything out on it. Once I had my layout marks set I drilled 1/2" holes at the ends of the slot locations. Then I cut them with a zip wheel on my grinder. Woke up tasting that stuff in my mouth. The gearbox I drilled 7/16th and tapped the holes for 1/2". Going into the frame I already had two 1/2" through bolts but added three more for torsional strength. The last three I tapped into the frame.

[Clover]

Did some dialing in of my mill last couple days. Had some thick white oak slabs and 5 or 6 pin oaks to cut up. Took a bit to get the governor set right and for awhile I was worried I got the Pulley sizing wrong as the rpm's were dropping to low for my liking. Much improved cutting speed now and the head movement up and down with hydraulics is great.
Here are a couple boards I cut today.









Notice anything missing?