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#42 ·
I am kind of beating you to the punch here because I saw your video of the belt drive working almost as soon as you posted it. If you are familiar with how a bandsaw tracks using crowned pulleys, the more tension you add to the belt, the more precise your belt tracking will need to be. A bandsaw accomplishes this by having the two wheels (pulleys) lined up true to one another, but allowing the top driven wheel to be adjusted by tilting through its axis of rotation. If the blade wants to run towards the edges of the wheels, you lean the top of the driven wheel towards the direction it is walking out on, and it will move back the other way. I hope I am explaining that to where it is understandable.

My point is that you might be time ahead now to make your lower mount for your pulley to be adjustable to aid with tracking once you get the belt tension up to where it needs to be. Maybe not, but I think it is a likely possibility. It may also help with the belt wanting to walk off once it is unloaded.
 
Discussion starter · #43 ·
Started making the mounting bracket for the right-angle drive gearbox.
This is made out of .150 thick steel plate.

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Machining slots for the mounting bolts into 1/4 inch thick steel plate.

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This plate is fastened onto the side of the frame and the bracket on the gearbox is tack welded to it.
The slots will allow me to adjust this bracket forward or backward to align the flat belt if I need to once I get it running.

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Strips of the .150 thick steel are welded onto this to give it that extra support that it will need.

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This mounting bracket is fastened in place.

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I did a lot of measuring to make sure that I had everything lined up correctly with mounting the gearbox.
When I did a test run on this, I didn't have to move this gearbox at all from where I had it set so all that measuring worked out right.


Link to my youtube video of the belt drive working.

 
Discussion starter · #44 · (Edited)
Banjojelly said:
I am kind of beating you to the punch here because I saw your video of the belt drive working almost as soon as you posted it. If you are familiar with how a bandsaw tracks using crowned pulleys, the more tension you add to the belt, the more precise your belt tracking will need to be. A bandsaw accomplishes this by having the two wheels (pulleys) lined up true to one another, but allowing the top driven wheel to be adjusted by tilting through its axis of rotation. If the blade wants to run towards the edges of the wheels, you lean the top of the driven wheel towards the direction it is walking out on, and it will move back the other way. I hope I am explaining that to where it is understandable.

My point is that you might be time ahead now to make your lower mount for your pulley to be adjustable to aid with tracking once you get the belt tension up to where it needs to be. Maybe not, but I think it is a likely possibility. It may also help with the belt wanting to walk off once it is unloaded.
Click to expand...
I have no problem with the belt tracking true with the tensioner engaged. The tighter I press the tensioner in the truer the belt tracks. It is only when the belt tension is realised that it slides off the top pulley.

The only reason that the belt comes off the pulley when it is released is because it is sitting on the rotating drive pulley.
If the drive pulley was on the bottom, then the belt would fall away from the rotating pulley and it would stay in place then.
A non moving belt will not stay on a rotating pulley unless it is held in place by a guide.
 
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#45 ·
jdcrawler said:
I have no problem with the belt tracking true with the tensioner engaged. The tighter I press the tensioner in the truer the belt tracks. It is only when the belt tension is realised that it slides off the top pulley.

The only reason that the belt comes off the pulley when it is released is because it is sitting on the rotating drive pulley.
If the drive pulley was on the bottom, then the belt would fall away from the rotating pulley and it would stay in place then.
A non moving belt will not stay on a rotating pulley unless it is held in place by a guide.
Click to expand...
Not sure how it would work but maybe putting a dog clutch on the rotating pulley. Something like used on a hand crank engine only fixed so you can decide when to disengage it. Then the flat belt could be tensioned all the time.
 
Discussion starter · #46 · (Edited)
Ariens93GT20 said:
Not sure how it would work but maybe putting a dog clutch on the rotating pulley. Something like used on a hand crank engine only fixed so you can decide when to disengage it. Then the flat belt could be tensioned all the time.
Click to expand...
Interesting idea but way more complicated to build than what I would want to get into on this tractor.

Thinking more on that clutch drive idea. ......
I have this two piece dog clutch drive that would work for that. It would take way too much work to make it work on the drive pulley on the engine but I could make it work with the shaft going from the bottom pulley over to the right angle gearbox.

I would have to cut the shaft under the tractor that connects the bottom pulley to the right angle gearbox and make it so the two ends are fit together with a bushing so one end vcan rotate while the other end is still.
Then I could fasten one end of this dog clutch to one end of the shaft and make the other end so it slides back and forth on a keyway on the other end of the shaft.
That way the flat belt would run all the time and the sickle mower could be engaged and disengaged by sliding the one end of this cog clutch drive in or out.
....... thinking ...... thinking ...... thinking .......
 
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#48 ·
jdcrawler said:
Interesting idea but way more complicated to build than what I would want to get into on this tractor.

Thinking more on that clutch drive idea. ......
I have this two piece dog clutch drive that would work for that. It would take way too much work to make it work on the drive pulley on the engine but I could make it work with the shaft going from the bottom pulley over to the right angle gearbox.

I would have to cut the shaft under the tractor that connects the bottom pulley to the right angle gearbox and make it so the two ends are fit together with a bushing so one end vcan rotate while the other end is still.
Then I could fasten one end of this dog clutch to one end of the shaft and make the other end so it slides back and forth on a keyway on the other end of the shaft.
That way the flat belt would run all the time and the sickle mower could be engaged and disengaged by sliding the one end of this cog clutch drive in or out.
....... thinking ...... thinking ...... thinking .......

View attachment 2624620 View attachment 2624621
Click to expand...
I didn't intend on keeping you up all night.
 
Discussion starter · #49 ·
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Discussion starter · #50 ·
I'm going to make some drastic changes to the design of the flat belt drive system.
Yesterday, Arens93GT20 asked about the possibility of putting some sort of dog clutch on the drive pulley on the engine so it could be disengaged from the engine when I wanted to stop the belt.
This would keep the belt on the pulley because the pulley would also be stopped from moving.
With doing that, the belt tensioner could be set to hold pressure on the belt all the time.

It's and interesting idea but not really feasible in this case because the end of the crankshaft is flush with the end of the pulley. The end of the engines crankshaft would have to be sticking out past the pulley far enough to mount the dog clutch assembly on it.


Thinking about this later, I realised that while the dog clutch will not work on the engine pulley, it will work on the shaft under the tractor that goes between the bottom pulley and the right angle gearbox.
I also remembered that I just happen to have the two mating parts for a dog clutch.

Image



So ... with adding the dog clutch to the lower drive shaft, the belt tensioner will no longer engage and disengage the belt.
It is now be set so the belt is engaged all the time.

Image



I have a fixed position, spring loaded rod mounted under the tractor that is connected to the tensioner lever arm.

Image



The other end of this rod slips thru a threaded rod. The spring tension is adjusted by turning the nut on the right end of the threaded rod. Once the tension is set, the threaded rod is locked in place with the a locknut of the left side up against the threaded bracket.
After everything was assembled, I saw that there is room to put the locknut on the right side of the threaded bracket so I'm going to switch that locknut.
This will allow more of the threads on the rod to be holding the spring pressure.

Image



These are the parts to make the dog clutch work :
The two dog clutch halves.
A splined shaft with a splined collar to fit onto it ( parts off a Ford model-T driveshaft and universal joint ).
A clutch throwout bearing fork to move the one side of the dog clutch in and out ( off a Ford model-A ).

Image



One half of the dog clutch will be mounted on the input shaft of the gearbox.

Image



The other half of the dog clutch will have the splined collar fit inside it.

Image



The splined shaft will be fit onto the drive shaft.
A bearing will be fit inside the dog clutch that will be on the gearbox and the end of the drive shaft will fit into it so that the shaft will spin on the bearing when the dog clutch is disengaged.

Image
 
#51 ·
jdcrawler said:
I'm going to make some drastic changes to the design of the flat belt drive system.
Yesterday, Arens93GT20 asked about the possibility of putting some sort of dog clutch on the drive pulley on the engine so it could be disengaged from the engine when I wanted to stop the belt.
This would keep the belt on the pulley because the pulley would also be stopped from moving.
With doing that, the belt tensioner could be set to hold pressure on the belt all the time.

It's and interesting idea but not really feasible in this case because the end of the crankshaft is flush with the end of the pulley. The end of the engines crankshaft would have to be sticking out past the pulley far enough to mount the dog clutch assembly on it.


Thinking about this later, I realised that while the dog clutch will not work on the engine pulley, it will work on the shaft under the tractor that goes between the bottom pulley and the right angle gearbox.
I also remembered that I just happen to have the two mating parts for a dog clutch.

View attachment 2624694


So ... with adding the dog clutch to the lower drive shaft, the belt tensioner will no longer engage and disengage the belt.
It is now be set so the belt is engaged all the time.

View attachment 2624686


I have a fixed position, spring loaded rod mounted under the tractor that is connected to the tensioner lever arm.

View attachment 2624687


The other end of this rod slips thru a threaded rod. The spring tension is adjusted by turning the nut on the right end of the threaded rod. Once the tension is set, the threaded rod is locked in place with the a locknut of the left side up against the threaded bracket.
After everything was assembled, I saw that there is room to put the locknut on the right side of the threaded bracket so I'm going to switch that locknut.
This will allow more of the threads on the rod to be holding the spring pressure.

View attachment 2624688


These are the parts to make the dog clutch work :
The two dog clutch halves.
A splined shaft with a splined collar to fit onto it ( parts off a Ford model-T driveshaft and universal joint ).
A clutch throwout bearing fork to move the one side of the dog clutch in and out ( off a Ford model-A ).

View attachment 2624689


One half of the dog clutch will be mounted on the input shaft of the gearbox.

View attachment 2624690


The other half of the dog clutch will have the splined collar fit inside it.

View attachment 2624691


The splined shaft will be fit onto the drive shaft.
A bearing will be fit inside the dog clutch that will be on the gearbox and the end of the drive shaft will fit into it so that the shaft will spin on the bearing when the dog clutch is disengaged.

View attachment 2624692
Click to expand...
:LOL:
///Nice-Nice! But--somehow--I just knew that part (s) would be in stock-maybe back on that dusty shelf..
Lo and behold!!!
And I ask the other viewers--are you surprised??
glenn
 
Discussion starter · #54 ·
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#55 ·
I think this is a great solution. I was concerned that with varying tension from your tensioner using it as a clutch as well as the difference between the sickle being under load and just coasting was going to give you belt tracking issues. I think having the belt under tension all the time and allowing the tensioner to work almost as a guide is going to work out much better.
 
#56 ·
jdcrawler said:
I won't live long enough to do that.
Click to expand...
//////////
Hate to say that-Ray, but I was thinking the same thing, and I have never seen your place. It's just from your comments and your workmanship- you SAVE everything. I applaud you! (y) (y)
glenn
 
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Discussion starter · #58 ·
Here you can see that the splined shaft has been braised onto the piece of round bar stock.

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I've machined the excess brass out of the grooves.

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This allows the collar to slide all the way back now, gaining about 3/4 inch more travel.

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I'm not going to use the bearing to hold the end of the splined shaft in place as I had first planned on doing.
I've decided that this whole dog clutch assembly is going to be encased inside a metal box that will hold 90W gear lube.
So instead of using the sealed bearing to hold the spline, I will use a bronze bushing. With everything running in oil, it will work much smoother and last longer than it would out in the open.

I'm going to put a hardened 1/2 inch diameter dowel pin in the end of the spline and it will run inside the bushing.
The splined shaft isn't super hard but it is hard enough that it soon takes the sharp edge off a drill so I'm using end mills to bore the hole for the dowel pin.

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The dowel pin is then pressed into the end of the spline.

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I pressed a piece of round aluminum inside the dog clutch.
This is being machined out for the bushing to go into it.

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The bushing is pressed into the hole.

Image



This half of the clutch fits onto the input shaft of the gearbox.
Once everything is ready for assembly, the shaft will be drilled down thru the holes in the clutch and Split pins will be pressed into them to fasten the clutch to the shaft.

Image



The splined shaft fits into the center of the clutch.

Image
 
Discussion starter · #59 ·
For the other half of the dog clutch, I have this piece of 3 inch diameter steel with a 1-1/2 inch hole in it.
Unforentually, the splined collar is smaller then this hole.

Image



So I'm turning out a steel bushing to fill the gap.

Image



This is pressed into the hole.

Image



And the splined collar is then pressed into it.

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The front part of the 3 inch diameter piece has been turned down to fit into the clutch.

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A piece of bearing bronze is then turned down.

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This is pressed into the other end of the 3 inch piece.

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Then the center is bored out.

Image



The splined shaft fits up into the splined collar.

Image



And it slides all the way in so the smooth part rides inside the bronze bushing.
The way the clutch is supported on both ends of the shaft.

Image
 
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jdcrawler
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