Screw drive garden tractor

[Rednic79]

yes!! your are absolutely right! that's where it went wrong! awesome! that was buggin me a bunch

Nice job!

A thought on the calculation for the ring... I think you would want to use the circumference of the tube as a starting point. Then add the spacing that you want, which gives you your new circumference. That would come out to about 11.3" I.d.

I'm not sure if that's right either, but it's the formula I came up with a couple days ago when I was thinking about this.

 

[Rednic79]

OK, gotcha. So, another question - could you weld the rings together first, or would it just take way too much to stretch it all apart in one piece?

yeah, that was one way I was considering....I would have to stretch them off the pod somehow first then slide them on I think...maybe pull them with a winch of something

 

[CNC Dan]

well I started on the screws, what a nightmare...check it out

http://youtu.be/0E7m3U3kuy0

You are using 2D math to solve a 3D problem.

figure circumference as the base of a right triangle and the pitch as the height of the triangle. the resulting hypotenuse will be the inside circumference of your flighting. divide that by PI to get your diameter.
since you already have your tubes already made, just wrap a string around it and then measure the length of the string and divide by PI.

As you may know, there are places that will make flighting to fit your tubes.

 

[GolfAddict]

But at this point, isn't he going to want to make the other side identical?

 

[CNC Dan]

Someone beat me to it.

Anyway, I think you will need to add another flight in between the one you have.

I think welding all the rings first would be the best way to do it. Use a winch to pull the end.

 

[CNC Dan]

But at this point, isn't he going to want to make the other side identical?

Yup. Unless he uses some kind of independent variable speed drive the machine is always going to try to turn one way or the other.

 

[Rednic79]

yeah, at this point i'm going to do the same on the other side...I totally understand what I did wrong, but it's too late now. as long as I space the next auger out the same at 9" it should be ok. it worked before, it will work again. a second flight is a possibility for sure

 

[mikehaugen]

yeah, at this point i'm going to do the same on the other side...I totally understand what I did wrong, but it's too late now. as long as I space the next auger out the same at 9" it should be ok. it worked before, it will work again. a second flight is a possibility for sure

A second flight may be a good idea, at the very least it will give you more ground contact on harder surfaces.... but how do you put it on now? :laughing:

 

[mikehaugen]

You are using 2D math to solve a 3D problem.

figure circumference as the base of a right triangle and the pitch as the height of the triangle. the resulting hypotenuse will be the inside circumference of your flighting. divide that by PI to get your diameter.
since you already have your tubes already made, just wrap a string around it and then measure the length of the string and divide by PI.

As you may know, there are places that will make flighting to fit your tubes.

I was thinking that too at first, but my math shows 9.1 as the I.d. which seems small, so I figured it was wrong.

 

[Rednic79]

it would be very expensive in beer purchases.....

A second flight may be a good idea, at the very least it will give you more ground contact on harder surfaces.... but how do you put it on now? :laughing:

 

[CNC Dan]

A second flight may be a good idea, at the very least it will give you more ground contact on harder surfaces.... but how do you put it on now? :laughing:

Weld it all up, stretch it out, and then screw it on in between the existing one.

 

[Rednic79]

hard to say what's better....pressure = force x area...less screws...more force / penetration of the ground, can be done if needed though

Weld it all up, stretch it out, and then screw it on in between the existing one.

 

[CNC Dan]

hard to say what's better....pressure = force x area...less screws...more force / penetration of the ground, can be done if needed though

Have to wait to try it out. If it sinks in too much and there is a lot of drag on the tubes, more flights may be in order.

 

[Danno1]

I'm guessing they wouldn't work very well for more than one reason. The most serious is ou'd need to find righ and left hand culverts. To travel, the pontoons need to rotate in opposite directions. Otherwise, the tractor will travel sideways.

The shipping costs would be a killer. You'd have to get one fr south of the equator!!



.

 

[Rednic79]

wahh wahhh wahh

The shipping costs would be a killer. You'd have to get one fr south of the equator!!



.

 

[pappy60]

Great idea... going to watch how it goes... good luck...

 

[Rednic79]

well, its running anyhow...any thoughts?

http://youtu.be/1uVcs_tzQ5I

 

[pappy60]

Looked at the latest video #5

After looking at the Chrysler and Fordson (Posts 2 & 3) the spirals on them are really shallow... the spirals on yours would dig in and would take a lot more torque to turn them... maybe that is why the shaft bent...
What you made would be very difficult to turn.. you basically have two inclined planes pushing towards each other to provide forward motion, kind of like putting a block of wood between two gears... Think you are going to have to rework the spirals, maybe give them a less aggressive bite..

Hope you get it going, that would be a fun project.. and fun to drive also...
Good luck..

 

[Rednic79]

yeah it's possible that they are too big, some of the other Russian screw vehicles have an aggressive spiral thought. i can cut them down if need be. it is misleading since i only have one helix not two. most on the other machines have at least two spirals, the fordson has multiple, and yes it is less aggressive. i think the gear setup wasn't strong enough either way....i need to either abort the spider gear setup, of make it much beefier.

 

[Xfaxman]

Too bad these cost so much: https://www.surpluscenter.com/Top-Products/1-1-32-HP-RIGHT-ANGLE-GEARBOX-13-1423.axd