show your homemade splitter pics here

[glastron23]

this is a short video that my sister shot the first time we fired it up, was trying to set the pressures. Home made wood processor - YouTube

 

[bubbacuse77]

Here is mine. It has the Prince LSR 3060 with rapid extend.

 

[DiskDoctr]

That's just awesome!

I have some parts and working to figure out what else we'll need. I watch something like that and want to go out and start welding :licking:

Thanks!

- JC

 

[DiskDoctr]

Okay, I am having trouble sourcing a [reasonably priced] hydraulic motor for the chainsaw. Yeah, I'm sure some of you are either rolling your eyes or having nightmare flashbacks of your builds, but please bear with me

First, I'll share what I *think* I know for others who may have an interest.

Oregon recommends their 18HX (.404) chains are run at 8000 fpm (3000 is min).

RPM to FPM is calculated as follows:

(Chain pitch) x 2 x (# sprocket teeth) x RPM / 12 ;
Source: Chain Speed Calculations

In my case, .404 x 2 x 14 (largest sprocket I found) x 1800 (my tentative hydraulic motor) / 12 = 1696.8 FPM

@ 3k RPM = 2828 FPM
@ 5k RPM = 4713 FPM

My initial powerplant is my JD 455D rear hydraulics (28 GPM, 2500psi, 67 HP Turbo diesel). It is "JD yellow" not green crawler/loader. I removed the backhoe because of a leaking valve bank. (I have another backhoe, so the quick disconnect hoses make an excellent "donor")

So I don't care about HP at the moment. Figure design with "unlimited" and then later build a standalone power plant.

Sure, for $2500 or so I can buy a Parker F11 or a Danzco unit...yadda, yadda...but that is beyond my budget
****
So how do I speed up the chain?

Things I've considered:

1. Larger custom sprocket. But that may prevent chain from seating in bar properly as diameter increases beyond [some maximum] diameter? Setting the sprocket farther from the back of the chain will help some, but there is a limit and can lead to chain whipping.

2. Gear or sprocket gearbox with custom shaft. Hydraulic motor with big gear, drives shaft with small gear, other end of shaft is chainsaw sprocket. Problem is the RPMs. I'm not sure if standard gears would hold up to the speed, and then may need a cooling system (oil circulation)?

3. Pulley driven. Same problems with the RPMs. What is the practical and safe limit? Entire mechanism would have to pivot with the saw to maintain proper tension and alignment.

4. Run chain at slower speed. This could have a major impact on speed, which isn't critical, but the idea is to save both effort AND time Is it better to have more speed or torque? What is a fair tradeoff?


I am trying to design everything with 28 gpm and 3000psi, though my current system will be about 2500 psi. It will give us room to step up later.

Help?


Thanks in advance.

- JC

 

[PaleFX]

for you handy men that havea hoe on thier tractors, here's a neat idea. YouTube - Backhoe Wood Splitter 2

that has "Productivity" written all over it! lol!!! :laughing:

 

[muddstopper]

Okay, I am having trouble sourcing a [reasonably priced] hydraulic motor for the chainsaw. Yeah, I'm sure some of you are either rolling your eyes or having nightmare flashbacks of your builds, but please bear with me

First, I'll share what I *think* I know for others who may have an interest.

Oregon recommends their 18HX (.404) chains are run at 8000 fpm (3000 is min).

RPM to FPM is calculated as follows:

(Chain pitch) x 2 x (# sprocket teeth) x RPM / 12 ;
Source: Chain Speed Calculations

In my case, .404 x 2 x 14 (largest sprocket I found) x 1800 (my tentative hydraulic motor) / 12 = 1696.8 FPM

@ 3k RPM = 2828 FPM
@ 5k RPM = 4713 FPM

My initial powerplant is my JD 455D rear hydraulics (28 GPM, 2500psi, 67 HP Turbo diesel). It is "JD yellow" not green crawler/loader. I removed the backhoe because of a leaking valve bank. (I have another backhoe, so the quick disconnect hoses make an excellent "donor")

So I don't care about HP at the moment. Figure design with "unlimited" and then later build a standalone power plant.

Sure, for $2500 or so I can buy a Parker F11 or a Danzco unit...yadda, yadda...but that is beyond my budget
****
So how do I speed up the chain?

Things I've considered:

1. Larger custom sprocket. But that may prevent chain from seating in bar properly as diameter increases beyond [some maximum] diameter? Setting the sprocket farther from the back of the chain will help some, but there is a limit and can lead to chain whipping.

2. Gear or sprocket gearbox with custom shaft. Hydraulic motor with big gear, drives shaft with small gear, other end of shaft is chainsaw sprocket. Problem is the RPMs. I'm not sure if standard gears would hold up to the speed, and then may need a cooling system (oil circulation)?

3. Pulley driven. Same problems with the RPMs. What is the practical and safe limit? Entire mechanism would have to pivot with the saw to maintain proper tension and alignment.

4. Run chain at slower speed. This could have a major impact on speed, which isn't critical, but the idea is to save both effort AND time Is it better to have more speed or torque? What is a fair tradeoff?


I am trying to design everything with 28 gpm and 3000psi, though my current system will be about 2500 psi. It will give us room to step up later.

Help?


Thanks in advance.

- JC

I think you have your numbers off on the chainspeed. If you look up huskys 3120 chainsaw, you will see that that saw runs the .404 chain. The saw has about 8.4hp, maximum power speed of 9000rpms. This hp and engine speed moves the 404 chain at 65.95 fts or 3957fpm. Maybe Orgeon says you can spin their 404 chain at 8000fpm, but I wouldn稚 want to be anywheres around it if it came apart.
HUSQVARNA 3120 XP® - Chainsaws

A Cross 1cuin motor with around 15gpm/3000psi will turn your chain sprocket at 3000rpms, Using a 12tooth sprocket will get you close to 4000fpm. Hp will be way more than the 8.4hp of the 3120 husky chainsaw and the setup should cut way faster without stalling than the husky.

 

[DiskDoctr]

I think you have your numbers off on the chainspeed. If you look up huskys 3120 chainsaw, you will see that that saw runs the .404 chain. The saw has about 8.4hp, maximum power speed of 9000rpms. This hp and engine speed moves the 404 chain at 65.95 fts or 3957fpm. Maybe Orgeon says you can spin their 404 chain at 8000fpm, but I wouldn稚 want to be anywheres around it if it came apart.
HUSQVARNA 3120 XP - Chainsaws

A Cross 1cuin motor with around 15gpm/3000psi will turn your chain sprocket at 3000rpms, Using a 12tooth sprocket will get you close to 4000fpm. Hp will be way more than the 8.4hp of the 3120 husky chainsaw and the setup should cut way faster without stalling than the husky.

I think that saw uses a different chain? I was looking at the specs page for the 18HX http://www.oregonchain.com/harvester/pdf/18HX.pdf It is a harvester chain.

Maybe the .404 you mentioned would be worth checking out....

I thought the harvester chains would last longer?

Thanks for the info on that motor, I'll definitely look into that, too! This is the kind of experience I was hoping to hear about.

- JC

 

[DiskDoctr]

A Cross 1cuin motor with around 15gpm/3000psi will turn your chain sprocket at 3000rpms, Using a 12tooth sprocket will get you close to 4000fpm. Hp will be way more than the 8.4hp of the 3120 husky chainsaw and the setup should cut way faster without stalling than the husky.

Please share with me the math to get 12 tooth @ 3000rpm to make 4000fpm.

The 3120 you mention runs @ 9000rpm to get its high fpm, which is exactly the problem I am having- running at 1/2 the rpms with "normal" hydraulic motors, or spending big for the faster F11.

Do you know how many teeth are on the sprocket of the 3120 stock? Are they publishing somewhere the chain speed with the 11 tooth?

- JC

ETA: According to this parts listing (page 37), this saw comes with a 7 tooth sprocket. http://www.husqvarna.com/ddoc/HUSO/HUSO2010_USen/HUSO2010_USen__1153183-26.pdf

So it seems a 14 tooth sprocket at half the rpms (4500rpm) should equal the same (approx) fpm of about 4k fpm. This seems to match my calculations above...unless I'm missing something?

 

[glastron23]

Disk.. you can use this to get FPM of the chain... Speed Calculator
you need to know the diameter of the sprocket and motor speed
as far as chain speed goes, with a gas engine you don't have the torque to work with so they need the speed to cut, with a hydraulic motor you have the torque but not the speed to work with so you can work with a much lower speed.

 

[muddstopper]

Please share with me the math to get 12 tooth @ 3000rpm to make 4000fpm.

The 3120 you mention runs @ 9000rpm to get its high fpm, which is exactly the problem I am having- running at 1/2 the rpms with "normal" hydraulic motors, or spending big for the faster F11.

Do you know how many teeth are on the sprocket of the 3120 stock? Are they publishing somewhere the chain speed with the 11 tooth?

- JC

ETA: According to this parts listing (page 37), this saw comes with a 7 tooth sprocket. http://www.husqvarna.com/ddoc/HUSO/HUSO2010_USen/HUSO2010_USen__1153183-26.pdf

So it seems a 14 tooth sprocket at half the rpms (4500rpm) should equal the same (approx) fpm of about 4k fpm. This seems to match my calculations above...unless I'm missing something?

I went back and done the math agin. when I was posting I was working off memory, which isnt as good as it once was. Yea, I was way off.

The chain speed is based off the rpms X the circumference of the sprocket. The dia of the 12 tooth sprocket is 2.75 xpie'=cic of 8.639 inches. Multiply this times 3000 rpms=25917inches per min/by 12in=2160fpm. A 5000rpm motor would yield a speed of 3600fpm and i believe this to be the number I was actually trying to remember when I originally posted.

Just for info, the dia of the 14tooth sprocket is 3 5/16 or 3.3125 x's Pie=10.406x's 3000rpms=31218 ipm/12=2601fpm and at 5000rpms=4335fpm

I am not sure of the max rpms of the cross motors, the 3000rpms is based on 15gpm flow, you may or maynot be able to increase the speed of the motor by throwing more flow at it, but i dont know how safe that might be or how long the motor would last.

Also, if you choose to use the 14tooth sprocket, keep the bar as close to the sprocket as possible to reduce the likelyhood of chain throw. Use a bar with a width similar to the diameter of the sprocket. A narrow bar will cause the chain to rideup out of the guide rail of the bar and jump off the sprocket. A wider bar will also allow for more ajustability when you start to encounter chain stretch.