3 point hitch string trimmer, Mark II

   / 3 point hitch string trimmer, Mark II #1  

PHPaul

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Kubota B2650 with cab, Pasquali 986
I posted a topic on the original version here.

The right angle drive I used was VERY used when I got it and didn't like being run upside down, probably due to lube issues. In any event, it failed catastrophically.

I decided to resurrect the project this Spring and got a 30 hp-rated brush hog gearbox from Surplus Center and redesigned the mount and drive belt arrangement.

3pht1.jpg


3pht2.jpg


3pht3.jpg


With a heavier gearbox, mounted as designed and a better PTO shaft with a slip clutch, I think this version should work quite well. String head speed seems a little low but it works okay. I may mess with pulley sizes a little down the road. I left the intermediate shaft long until I was sure I had the pulley alignment right. I'll trim that to length.
 
   / 3 point hitch string trimmer, Mark II #2  

texasranger556

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JD 4400
I like it. Do you have a shear bolt or anything to keep from bending if you catch it on something?
 
   / 3 point hitch string trimmer, Mark II
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PHPaul

PHPaul

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Kubota B2650 with cab, Pasquali 986
I like it. Do you have a shear bolt or anything to keep from bending if you catch it on something?

No, which may well come back to bite me in the sitter. I run in low gear with one hand on the 3 point hitch lever and lift it up over anything I can't cut.
 
   / 3 point hitch string trimmer, Mark II #4  

kthompson

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I like it also. Would be great for our pond or ditches. Not the sides of the ditches but growth coming out the top. I have seen a slip type design which was basically a length of metal inside a sleeve with heavy spring to allow your cutter to swing back if you were to hit something. You also could use a simple sheer pin design if you seldom hit something. Wonder about putting a hinge into the design where you could adjust the cutter head up or down some for cutting on angle.

Please know I do find your design great. Do think you ought to cover the belts to keep what ever is being cut from getting between the pulley and the belt.
 
   / 3 point hitch string trimmer, Mark II
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PHPaul

PHPaul

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Kubota B2650 with cab, Pasquali 986
I like it also. Would be great for our pond or ditches. Not the sides of the ditches but growth coming out the top. I have seen a slip type design which was basically a length of metal inside a sleeve with heavy spring to allow your cutter to swing back if you were to hit something. You also could use a simple sheer pin design if you seldom hit something. Wonder about putting a hinge into the design where you could adjust the cutter head up or down some for cutting on angle.

Please know I do find your design great. Do think you ought to cover the belts to keep what ever is being cut from getting between the pulley and the belt.

Thanks!

I do intend to put sheet metal covers over the belts, especially the lower one. I wanted to make sure everything was going to work as-is before doing that.

Being able to tip the string head at an angle to trim down into ditches would be great, but the only way I can see to do that would be a hydraulic motor drive and a cylinder to adjust the angle. That gets into serious money (at least compared to my budget) quickly.

I AM noodling over the idea of putting a top-and-tilt on the tractor which would be more generally useful, especially with my box blade. then I could raise the whole thing up and tilt the string head down at an angle.

I used it for a year in it's original form before the right angle drive died and didn't run into (arrrrr, humor!) a situation where a break-away would've been needed. Doesn't mean I won't in the future of course, but for right now it's not high on the list.
 
   / 3 point hitch string trimmer, Mark II #6  

jimmychew

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Cub Cadet 1200
Great job on the trimmer. What do you use for string, piano wire?
 
   / 3 point hitch string trimmer, Mark II #7  

ArlyA

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Polaris Boss 6x6 with pods (tracks) Center actuating lawn mower by Husky
Looks like regular string trimmer plastic to me. We use the .155 version by the roll but looking to try .170 or 180 which is a bit harder to locate on our whackers. PHpaul do let us know which string you are using and do show its attachment system.
 

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   / 3 point hitch string trimmer, Mark II
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PHPaul

PHPaul

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The string head is off a Craftsman walk-behind trimmer and the string is the heavy plastic with a square cross-section. Not sure what size it is. Edit: I went out and measured it. It's .180 measured on the diagonal.

I cut off a 6' length, cut it in half and thread it like this:

string.jpg


Leaving two approximately 16" pieces on each side to do the cutting.
 
   / 3 point hitch string trimmer, Mark II #9  

metalbender

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A surplus 12 volt linear actuator would probably control angles.
 
   / 3 point hitch string trimmer, Mark II #10  

TractorGuy

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N. FL
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I've been thinking about building something like this. Might go with swinging blades for a disc mower instead of string.

You don't need a shear bolt on belt driven mowers. Finish mowers don't have one. They depend on belt slip.
 
 
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