Hybrid Rotary Cutter Proof of Concept

[dadohead]

A flail mower does alot better job than a rotory cutter on grass. Where they dont and a rotory shines is woody thicker material. I think you just have the wrong mower.

Flail mowers are wonderful if you have the power.

 

[John0829]

I find the flail uses LESS power than a rotary, judging by the amount of fuel the tractor uses cutting the same area, same conditions.

 

[Runner]

Flail mowers are wonderful if you have the power.

The problem with flail mowers is they don't cut high enough.

 

[airbiscuit]

They do if they are cutting cannabis

 

[Sportsman762]

Your design is similar to the RD990X finish mower they make. I cannot find any photos of the underside of one to post.

RD990X - Woods Equipment

Heavy-Duty Your Most Versatile Finish Mower Move from rough, weedy farmland to commercial lawns and landscapes with a finish-cut quality. Easy Maintenance EZ-Change™ Blade System allows blade change in five steps with a 3/4" wrench. No impact gun or torch required. Unmatched Gearbox PROTECTION...

woodsequipment.com

k, I did visit Woods. I sent them a longer version of the video; they invited me down. Wonderful people! Know that I dont want money... I just want somebody to improve their offerings! We spent the day talking and mowing. We did some side-by-side cutting in some of the toughest 24" fields I ever seen! Woods used their smallest tractor: a 24hp pto NH and a 6' HD single spindle and a 6' rear finish. I used my JD and concept mower. The finish mower could barely get through a pass. Their 6' single was impressive but still had rh tire track. My mower did great! They showed interest

Your craftsmanship is top notch. Keep up the good work.

Can you provide detail on how you decided what baffling to use? What is the purpose of the short baffle on the front? I know nothing about mower deck design and am curious how they work. Thanks!

 

[Jaybr]

Your design is similar to the RD990X finish mower they make. I cannot find any photos of the underside of one to post.

RD990X - Woods Equipment

Heavy-Duty Your Most Versatile Finish Mower Move from rough, weedy farmland to commercial lawns and landscapes with a finish-cut quality. Easy Maintenance EZ-Change™ Blade System allows blade change in five steps with a 3/4" wrench. No impact gun or torch required. Unmatched Gearbox PROTECTION...

woodsequipment.com

Your craftsmanship is top notch. Keep up the good work.

Can you provide detail on how you decided what baffling to use? What is the purpose of the short baffle on the front? I know nothing about mower deck design and am curious how they work. Thanks!

I mow my pastures with an RD990x and I'm very pleased with it. I don't think Woods makes that style mower small enough for the OP though.

 

[RayIN]

I've often thought an offset finish or rotary mower would be ideal for reaching under trees, ditches and fences.

Some flails are offset, and are interesting, but not many rotary or finish mowers are.

Thoughtful concept and it looks like you fabricated it very well!

About 40 years ago I saw a towable rotary mower with 3 spindles, the 1 was directly behind the tractor, the 2 was offset to the starboard side, the 3 was offset to the starboard side of #2 spindle and it had a support wheel behind the #3 spindle. it must have stuck out 8' to the starboard side of the tractor.
I stopped and looked at is with buying in mind; however the deck was rusty, plus I only owned a H. Ferguson 30 at the time and severely under-powered for such a mower.
I've searched the web several times without success in finding anything similar. Today all orchard mowers have a trailing arm to move around tree trunks. What I was was strictly a rotary mower machine. I think I remember it being a rusty green color.

 

[dadohead]

Your design is similar to the RD990X finish mower they make.

It is a similar  intent for sure. For the RD990X, they took their finish mower, mounted swing blades, and called it a hybrid. It still has all the finish mower traits though: shallow deck, high tip speed, designed to cut 1/3rd of the plant. I considered one... dont have enough tractor though.

Years ago, Woods  did make a mower that is very similar: D80.

It was a commercial duty (1400 lbs!), conventional rotating, offset spindle cutter for higher HP tractors. It wasn't offset so didnt backsweep tire tracks. It sold well for years though. More modern D80's are gear driven, timed, counter-rotating. $$$$

Can you provide detail on how you decided what baffling to use? What is the purpose of the short baffle on the front? I know nothing about mower deck design and am curious how they work. Thanks!

Mower decks are extremely complex. We hired a university years ago (researching helicopter rotor blades) to apply their work to mowers. I gave them CAD models and a machine (with known cut quality weaknesses) to study. Mower design is sort of a 'black art'... maybe science has caught up? Ha no! After months, the department head told us "We study helicopters; we're good at it. Your mower is multiple rotors spinning next to each other! Then surrounded by a shroud!! Then MASS is introduced!!!" A least we learned we weren't missing any new technology!

A mower creates a flow field underneath. Heavy material is 'slung'; the lighter material follows the flow. Generally, the grass will go from high pressure regions to low pressure regions.

My guess is you're asking about the baffle in the upper left? The bottom of the pic is the front of the mower. You can see how the RH spindle (front) would want to hand-off all of its discharge to the rear one... that was expected. Ring baffles were needed to isolate the chambers. In testing, the RH chamber (in the pic) discharged very nicely right out the back. The left chamber did not! It carried the material too long and slung it along the rear of the mower combining both discharges into one big wind-row... very ugly. To change that I inserted a "cut-off" baffle (upper left in pic). It is there in the flow field (about 3/4" from the blade wing) to create a high pressure wall. The material comes along the LH side toward a high pressure wall or veer out the back to "0" pressure.... so it goes out the back. Cut-off baffles work well but create noise. Get them too close to the blade and you build a siren! :<(

 

[ptsg]

I've often thought an offset finish or rotary mower would be ideal for reaching under trees, ditches and fences.

Some flails are offset, and are interesting, but not many rotary or finish mowers are.

Thoughtful concept and it looks like you fabricated it very well!

Not to steal the OP's thread by any means, but it does exist.

Here is an example. Rotary cutter, or technically a chain mulcher, with hydraulic side shift and an hydraulic strimmer attached to it to mow as close to trees and fences as possible.

This one happens to be spring loaded but there are versions with hydraulic retract where a finger pushes a valve and retracts the strimmer in order to no hurt the trees.

Available in flail cutters too.

 

[Runner]

Your design is similar to the RD990X finish mower they make. I cannot find any photos of the underside of one to post.

RD990X - Woods Equipment

Heavy-Duty Your Most Versatile Finish Mower Move from rough, weedy farmland to commercial lawns and landscapes with a finish-cut quality. Easy Maintenance EZ-Change™ Blade System allows blade change in five steps with a 3/4" wrench. No impact gun or torch required. Unmatched Gearbox PROTECTION...

woodsequipment.com

Your craftsmanship is top notch. Keep up the good work.

Can you provide detail on how you decided what baffling to use? What is the purpose of the short baffle on the front? I know nothing about mower deck design and am curious how they work. Thanks!

I was thinking of the RD990X also. It can cut as high as 7", but too big for a medium compact tractor (1200lbs) and needs min 45HP.