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Wood Processor on the Slide

Started by jmur1, August 14, 2017, 11:46:51 AM

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jmur1

The final critical component that was analyzed, considered, and reconsidered was the large blade lever.  This device was an important design based on safety, operation, and maintenance. There were very important design assumptions made based on the potential risks of failure.  Shaft sizing and placement along with other mounting positions were part of this requirement.  Pic 19 and 20 show the first concept layout for the lever design.  A sample results plot is shown in Pic 21.



 

Pic 19



 

Pic 20



 

Pic 21
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jmur1

Here comes a perfect example of how something can work on paper and be quite full of issues when put into practice (or into trials).  The fabrication was completed to match Pic 15 (above).  There was also a shield added to the blade.  (You can see in Pic 22 and 23 below).  The action of the arm and movement of the sliding frame allowed far too much movement in the blade shaft and blade itself.  It would start to wobble and was contacting the guard on one side.  This was very bad for the blade sharpness  :-\ and also appeared quite unsafe.  Very quickly the lever arm went back to the drawing board. 
The proposed design had been a "cantilevered" shaft support.  This was quickly found to be too much weight and loading on the single arm support (and shaft) and so a reworked design was fabricated to provide the blade with support on both sides.  (simply suppported).  The rework is show in Pics 22 and 23   



 

Pic 22



 

Pic 23

This way the blade movement was limited to the pivot bearing tolerance and the flexure of the main lever arm.  The change made a world of difference to the performance!
Easy does it

jmur1

The processor model sliding frame was updated with some of the as-built changes to the original engine support and the load runner bracing.  The model was also reviewed for the required loading.  See Pic 24 and 25.



 

Pic 24



 

Pic 25
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jmur1

I have a quick very preliminary video of the processor's first test.  It was a long development process and this video is only provided as a proof of concept.  There are many more safety features that have been added to the machine since this was shot.  It is poor quality so I spruced it up abit.  I will update with better quality videos as the final components are added to the machine.  There were also a number of improvements made to the cycle time.  Keep in mind this is a 15hp machine!

https://youtu.be/0RYPSj6ScX8

Easy does it

hedgerow

jmur1
keep the pictures and videos coming. I away's enjoy homemade wood processing machines.

jmur1

Quote from: hedgerow on September 13, 2017, 03:09:28 PM
jmur1
keep the pictures and videos coming. I away's enjoy homemade wood processing machines.

Thanks hedgerow
I appreciate the interest.  I have read many of the posts in the forum and value the work done.

Easy does it

jmur1

Below in Pic 25 is the completed testing assembly.  I have made major revisions since this build and will share some of these findings in the following days - so any "would-be" builders can save the cost of the same mistakes.



 

Pic 25

I ran somewhere around two double-trailer loads through this arrangement.  (I'm told 14 bush cord each).  Anywhere between Ø 8" to Ø 20".  No where near full time usage but definitely a good sample for design purposes.  See Pic 26 for some of the wood.



    

Pic 26

Machine Background
15 hp Gas Engine.
1:1 Ratio belted pump driver
Several different pumps were run with moderate differences in performance.
16 gpm/4 gpm (3000 psi max)
22 gpm/6 gpm (3000 psi max)
22 gpm/4.8 gpm (3000 psi max)

Splitter Knife

The most time consuming (from failure) and critical design change was made to the Splitter knife.  It is very important to allow for enough space and provide direction for the split wood.  If the design includes more than quarters (four piece split) then be prepared to design for a movement away from the center point with a free path up and out.  After multiple failed attempts I was left with two versions that have since performed well. 

The first knife used 6" x 3/4" thick plate horizontal and vertical wings and had several revisions to stiffen the wings to survive all the knots encountered.  See Pic 27



 

Pic 27

The second knife used 8" x 1" thick plate horizontal and 1 1/4" vertical .  See Pic 28



 

Pic 28

   
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dave_dj1

Looks good, I can't wait to see a video of it in action.

jmur1

Quote from: dave_dj1 on September 18, 2017, 07:19:30 PM
Looks good, I can't wait to see a video of it in action.

Hi dave_dj1:
Just a couple of small items to finish off on the build.  Then I will break out the video.   
Easy does it

jmur1

I have a quick comment on the design of the wood delivery chute.  I had originally kept it level with the surface under the splitter knives.  I soon realized that the wood split and moved in all directions.  It is advisable to provide lots of space to avoid interference with the chute body.  Both designs of knife assemblies would occasionally send the wood downward, binding with the chute floor.  This would then cause the two stage pump circuit to drop into high pressure mode.  The extra waiting time is painfull and unnecessary.  I redesigned the chute several inches lower and much of the problem was corrected.  See Pic 29.  I still need to add holes to the chute floor the remove scraps.  As you can see from the photo my splitter ram runs on two rails (not a center guide).  It has its benefits - I will cover it next.



        

Pic 29
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jmur1

Here are my comments on the design of the sliding ram plate.  I wanted this machine to be capable of Ø20" logs.  So far it is really only good to Ø19" with this two rail design.  I came up with it based on my desired machine height and the various available parts (access system masts).   It definitely works very well with non-square cuts (when a log has bends in it).  It does experience extremely high side loads when misaligned or "bad" split logs are come across.  I have progressed from a simple I-Beam trolley assembly wheel (rated at 1000 lbs), to a heavy load runner (rated at 30,000 lbs) , to basic heavy plate guides.  Only now am I comfortable with the functioning result.  See Pic 30 for the I beam roller; See Pic 31 for the load runner layout; and finally see Pic 32 for the plate guides.   



 

Pic 30



 

Pic 31



 

Pic 32

A nice side benefit of this layout is the log stand.  I fabricated 2 spring loaded hinged plates where the log cuts land after the cut.  This locates them 95% of the time in the center of the splitter.  It also absorbs vertical movement from bad split logs.  The sawdust and small chunks can also pass through here.  See Pic 33



 

Pic 33

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jmur1

The hydraulic circuit was another carefully reviewed topic.  In the interest of maximizing speed and efficiency some additional components were added that have a significant return on investment. 

I had chosen the larger Ø5" splitter cylinder with the intent of splitting large (up to 20"Ø) logs into six.  It was after some time that I had issues with this cylinder from the above-mentioned side loading of the ram plate.  The 2" cylinder ram had bent one day on a knotty log that I really should have pitched out.  (I want to make this thing bullet proof so I have a habit of excessive testing).  smiley_lit_bulb At this point I thought why not increase the size of the ram as much as possible to reduce the amount of oil moving through the cylinder.  This would improve strength and increase speed. So I went to my local hydraulic shop and asked them to look at making the ram Ø3" or Ø3 1/2".  They came back after a couple of days and said that Ø3" is possible but Ø3 1/2" would be too much off the inner supports.  So I had this done.  See Pic 34.

   

 

Pic 34

I had been following another online inventor who claimed a piloted check valve for the return-to-tank line on the splitter cylinder is a good way to improve the speed of travel and thus reduce cycle time.  I added this valve to mine and then thought why not on the split cycle as well.  (Couldn't hurt).  I did this and can confirm a notable improvement.  I currently have the 22gpm/4.8gpm pump installed and measured the unloaded and cold out stroke at 10 seconds and the return stroke at 8 seconds.  See Pic 35 and 36



 

Pic 35



 

Pic 36
   
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jmur1

Just recently I updated my log stop from a basic spring-hose vertical line.  Originally I had approached the log stop as an ability to fine tune the cuts length to end up with a nice final cut that would be full size.  I had been using it without issue.  When I started selling wood I soon realized that some customers are not flexible with the concept of average stick lengths.  I have also been selling different sizes down to 12" long; so usually I can get 12" piece and then the waste is reduced.  This led me to create a solid stop.  I had also noted several other machines had invested alot of effort designing and installing custom devices to remove the stop as the cut was made to allow a free fall into the splitter bay.  I decided to start with a solid stop to see if the circular machine would act any differently (although the big circular machines definitely have a retracting system).  Another chain machine on this forum was using a solid stop without issue. 
Very quickly I had major issues with the solid stop - only about 1 in 5 were falling as they did before.  I thought over a solution and after abit of tweaking it works very well.  It may very well have been already done somewhere else, but here it is.  See Pics 37,38, and 39



 

Pic 37



 

Pic 38



 

Pic 39

To summarize it is basically a "hoe" shaped stopper (note: the vertical limit of the stop plate must be below the horizontal centerline of the pin so that when it pivots down it moves away from the log).  It is hinged and spring supported above the lever.  The spring holds it just below horizontal as seen it the images.  This works very well overall.  Only a couple of times has it kicked out the log so far.  I have run it for several hours like this.  I have also immediately noted a big processing speed increase.  You don't even realize how much time is wasted locating the logs with the flexible line method until you change it.
     
Easy does it

Tim

What is the design software that you are using?
Eastern White Cedar Shingles

jmur1

Quote from: Tim on September 23, 2017, 06:41:44 AM
What is the design software that you are using?

Hi Tim:
The software is Pro/E which is these days called CREO.

https://www.ptc.com/en/cad/3d-design/parts-and-assembly-modeling

jmur1
Easy does it

jmur1

I ran the processor for about one year with idler rollers on the front of the infeed path.  I also used a winch mounted on the saw frame to drag in stubborn logs.  Although this method worked it was definitely cumbersome and time consuming.  I had a source of potential power at the end of the belt drive.  All I needed to do was to connect a chain to the shaft and "borrow" some its power to drive live pulleys.  This modification was a valuable change to the design overall.  It became apparent that as much of the transfer system as possible must work with powered drives in order to work seamlessly with stubborn logs.  The live rollers were custom homemade.  I cut out 10 gauge metal sheets and welded them around a 1" bar.  See Pics 40 and 41.



      

Pic 40



 

Pic 41

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dave_dj1

That looks like an awesome upgrade  8)
I would do something similar if I ever build one.

jmur1

The hydraulic circuit was originally designed based on the requirements of single draw power.  In other words; the losses of the circular saw were not considered as a draw on the engine since the pump loading and the saw loading would take place independently.  This assumption was based on the fact that gravity could drive the saw into the log. 
In general the system works as designed.  It is very fuel-efficient.  2 tanks per day (14 qts over 8hrs) It does however seem to feel a little under-powered at 15 hp especially when the blade gets dull.  :'(.  The blade has lasted quite long between sharpenings (over 6 months between changes).
The hydraulic circuit temperature has not been measured yet but so far has not suffered any damage from heat.  There is no heat exchanger installed but steel lines were used on 90% of the piping connections for heat flow purposes.  The pump gets too hot to hold a hand on and the tank gets hot to the hand.  It is definitely a potential issue.  I have a tank level indicator that also shows temperature. It will be installed soon - until then I will take care from prolonged usage in hot weather.
A filter module was included and a 7th valve line requirement (for a live deck) has been accomplished by a pair of 12V switched valves.

See Pics 42,43,44



    

Pic 42



        

Pic 43



 

Pic 44
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jmur1

The belt feed conveyor worked better than I had originally imagined.  In the end I would have liked it to be longer than the 10' belt length (which resulted in the live roller conversions).  There was only a single issue with the construction that was noted over time. 
Directly over the log clamp the thin material of the original belt frame was crushed under the extra load.  The belt was removed and a thicker section of 1/8" sheet was added for strength.  The circular saw requires a healthy log clamp and this extra capacity is a requirement.
The belt works well for the logs and slabs alike.  An extra horizontal surface was added at the front of the processor to allow for loose slab material and bent logs to sit on if needed.  See Pics 45 and 46.



        

Pic 45



 

Pic 46
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jmur1

The sliding frame is supported by 4 adjustable load runners on 1" welded bar on top and 4 standard load runners on the bottom .  It has worked well since the first tests and remains in good functioning order.  I added some redundancy to the bracing (in case the angles on the frame ever became weakened and were to let go).  In general this system is very stable and  makes for accurate cuts.  There may be a long term need to limit the loading on this assembly with pressure relief valves on the lever arm cylinder and the sliding frame cylinder.  The assembly setup is shown in Pics 47, 48, and 49.



 

Pic 47



 

Pic 48

       

 

Pic 49
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hedgerow

Nice looking setup. I am surprised the single belt pulley set up has lasted. When I built my buzz saw I tried running one belt in the beginning and with a 15 Hp engine and a 36 inch blade it liked to eat up belts. I switched  to a double pulley belt set up and haven changed belts in years now.

jmur1

Hi hedgerow:
Funny you should mention that.  I had originally started with two belts in both belt positions - but then I installed a single belt clutch on the engine and had it work fine with only one belt running there.  I then tried a single belt on the final drive for the saw and it also worked fine.  I have been running them this way for about 2 years on the same 2 belts.  They look like they need to be replaced now - but that is not too bad all things considered.  I also have no spring for slack - the belts are tensioned tight- I should install a spring lever pulley to allow for slack  On a side note - I intend to try to run a 20 hp twin to see how much difference some extra power will make to the saw performance, I may then be entering back into the double belt territory.   
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dave_dj1

Got any pictures or video of it with some real wood on it? Those little pecker poles are no challenge! LOL

jmur1

Quote from: dave_dj1 on September 29, 2017, 03:42:19 PM
Got any pictures or video of it with some real wood on it? Those little pecker poles are no challenge! LOL

Hi dave_dj1:

I have been shooting video - still need to compile some of it.  I have done some big wood.



 

The machine is quite slow with the big stuff - but it still cuts it.  I have a 20 hp engine sitting on the bench ready to try out to address this issue. 

I have also been adding guards and safety devices.  I want to get these figured out before I release alot of info on the machine.  So far I have a working brake that is activated by the release of a hold to run switch.  At the same time the brake is activated the throttle is electrically switched to idle.  This was a required change since accessing the splitter bay is a necessary ability based on the crooked logs I cut.  (Lots of fresh ash around here).  I also added a big guard with 1/2" bullet proof plastic.  You can see the brake and the guard in the photo.   
Easy does it

dave_dj1

I love it, looking forward to the video.  8)

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