rc mower

[cdm]

no not a purpose built mowing bot that uses a conventional grass mower

an actual rc mower you can tow behind an rc vehicle. i was thinking about that given how much i like yard work. i have sod in the areas i want to trim which is a soft grass.

has anyone tried that before? i am thinking 12-14" bladespan (2 blades) and wire that up to an align 600 superpower that i am not going to use for anything.

before i go cut some metal, am i underestimating the power needed to get the job done?

[Stuff]

its not really the power, but more the RPM you need. pretty much same thing for snow blowers.

[cdm]

i can get 30000 rpm under load if i need to... i dont know if i need to scale up the speed or down (like an inverse relationship to size, smaller faster, bigger slower).

conventional household mowers run at 2500-3000 and bog to about 1800 before they stop working. i read that much while doing some research... also it seems mulching is what really bogs it down. just cutting through grass without mulching doesnt put much load

Im getting curious about that actually. I might cut up the blade holder tomorrow and use some crappy alum for blades (dont have any high strenght stainless sitting by) and see if i can get any trimming going on. like a proof of concept.

[Claus]

Be careful, things spinning that fast, if it comes apart it will be like a grenade.

[cdm]

Ill put on my riot gear. will let you all know how it went and if makes sense to proceed with it

[apfubar]

Be careful, things spinning that fast, if it comes apart it will be like a grenade.

Yep they do... Try 2 carbon fibre blades, 550mm long, spinning at 2600rpm... That's what some of the Helis run at... Not pretty when things go wrong.

Just as a thought why not try towing a commercially available battery powered mower? I know it takes some of the fun out of it, but it also reduces the risk...

Cheers,
AP

[Radio Control Trucker]

Instead of a power mower with the risk, how about a gang-mower. I used this type of mower on the golf course I worked at for nearly 11 years. Great machine, it runs forever.

http://www.lislesurplus.com/J/Jacobsen-gang-mower-fairway-reel-golf-course-farms/picture-5.jpg
http://media.pitchcare.com/L/ZzGLl5Exlj.jpg
http://www.gardenmachinery.in/full-images/tractor-gang-mower-775536.jpg

It's just a thought :D

- RCT

[WhiteWolf McBride]

RCT,

I had the same thought, but one thing is he'll need to drive the blades with a motor, not with a gear-box from the wheels. Thats why those hand-mowers are so tough to push/pull, the wheels drive the rotary blades.

It is do-able though... just need enough rpm on the blades, and enough traction/power on the puller.

Think that Big Bud that is still for sale would be perfect for pulling the mower, hm?

WhiteWolf

[scalepaintn]

yes!! a mower or a brush hog behind a john deere. love it. post up the how to's lets build it!

[Radio Control Trucker]

Maybe if you build it like the articulation unit I ran awhile back. It was 5 rotary units, belt-drive with a 3-point hood-up. The main gear box was driven by the PTO shaft.

http://www.globeaustralia.com.au/machinery/images/large/machinery_lastec_mowers_Equipment_catalogue_Lastec 2_img_5.jpg
http://www.youtube.com/watch?feature=player_detailpage&v=VGLNY5MxEIE

Good Luck :)

- RCT

[cdm]

Yes i looked at reel mowers but from what i read they use angles on the blades to cut (like scissors). how am i going to bend the blades and mount in those angles?

that would be much better of a design. im not sure if a straight bladed drum will cut at all

apfubar im no stranger to 600 size helicopters.. commercial mowers are heavy and downright impossible to turn. to use one you would need to go the conventional route - skeleton, wheelchair motors and some sabres.

[Radio Control Trucker]

No idea is a bad idea... they can all lend to the end product. Just take your time. You know what you want Chris, just use the suggestions you can and disregard the rest. :) :)

- RCT

[edwalsh18]

how about this? i would like one of these! guy cutting grass with rc tractor

https://www.youtube.com/watch?v=JIz0LJYvaIk

[Stuff]

hey, instead of high rpm blades, why not go the weed whacker route and use the nylon cable stuff?

[WhiteWolf McBride]

OH... a SCALE mower?

Thats another deal entirely. As for a spiral-blade-type mower, you could always harvest the guts of a duct fan... I'm not sure what they call the ones that are shaped like that, but they do make 'em. Then you just need to put an edge on the fan blades, and give them an edge to cut against, and presto.

I'd say duct/exhaust fans would be best to harvest for even a mower thats like a traditional mower, as its almost pre-balanced, has many blades, is metal, and could be easily sharpened. It wouldn't take that big a motor to drive one, and if you wanted a gang-type, it'd be easier to use a few small motors than to try to power them by chain/belt linkage (and gears might be messy/noisy)

Makes me almost want to rtry making one myself... even if it'd only cut a swath a few inches wide at a time... mebbe 6" if I used two... but it'd be a fun experiment. Could give it to my dad for his lawn ( he has a push-reel mower at the moment)

WhiteWolf

[doodlebug]

Have you seen Grainfarmer, Frank's swather project? haven't found the link yet?
Cheer's, Neil.

[cdm]

all my searches have led to normal sized mower conversions, commercial mower bots (awesome!) and others like that

all i did was get the motor mounted to a plate today and my allergies hit bad and i was done for. need to make the blade holder and some blades out of crappy alum - i should have ordered my stainless yesterday but its hard when you are sneezing constantly

if i ever buy those custom 1/8th tanks i can tow a real mower behind it. zip tie the throttle and go. hah. i just wish i could justify it.

[FlyingBeagle]

Here is a bruder conversion of a mower with two blades. The end of the video shows a quick photo of the underside of the mower deck.

http://www.youtube.com/watch?v=tRLMXiS0g5Y

It looks like a scale mower has the same problem that others have with their scale diggers, and that is that the grass you are cutting is still full scale just like the dirt and rocks don't scale down. I am just guessing here, but something like a scale bush hog may be the most feasible mower to build that may also be reasonably functional. Bush hogs are made to cut through heavier grass and brush, and the grass looks like it scales more like brush. You would need lower RPM's than a finish mower, but higher torque. May be a bit safer.

[Espeefan]

Here is Frank's windrower. It's a very cool model.

http://www.rctruckandconstruction.com/showthread.php?t=2435

Basically anything can cut grass, if it is swung hard enough. Have you ever goofed around as a kid, swinging a stick in tall grass? If you swing it hard enough, it will cut grass too, and it doesn't even have to be sharp. But the biggest thing to remember is to design a deck that gets the clippings out, as soon as they are cut. A design that keeps recirculating the clippings through the blades take a lot of power. Simple decks that throw the grass out right away stay cleaner, and use less power. This is why mulching decks don't work well in tall grass.

[doodlebug]

Thanks Nathan!
Cheers, Neil.


Here is Frank's windrower. It's a very cool model.

http://www.rctruckandconstruction.com/showthread.php?t=2435

Basically anything can cut grass, if it is swung hard enough. Have you ever goofed around as a kid, swinging a stick in tall grass? If you swing it hard enough, it will cut grass too, and it doesn't even have to be sharp. But the biggest thing to remember is to design a deck that gets the clippings out, as soon as they are cut. A design that keeps recirculating the clippings through the blades take a lot of power. Simple decks that throw the grass out right away stay cleaner, and use less power. This is why mulching decks don't work well in tall grass.

[cosworth34677]

i made one few years ago to prove it could be done. i used a simple plastic prop and a sheet alulimmim deck. and put it on a arm. this was for a unimog i made heres the vid
http://www.youtube.com/watch?v=J4f4_ytJx50&list=UUbjkqg_d_hA2OxV-9svcvtQ&index=11

i also made a drag behind type to for a older uninmog
http://www.youtube.com/watch?v=cnSsC6GDXHw&list=UUbjkqg_d_hA2OxV-9svcvtQ&index=13

[Finster]

Hope it's not bad form to post links to other forums, but here are two mower builds I happened to come across on a German forum. The one guy has a video of the Unimog mowing but he's made the video private. Use Google translate or Chrome viewer if you can't read German.

Unimog
http://www.das-baumaschinen-forum.de/index.php?page=Thread&threadID=4549&pageNo=1

Tractor
http://www.das-baumaschinen-forum.de/index.php?page=Thread&threadID=6174

[cdm]

No this is great thanks. I used to look at that site but not being a german speaker i generally do not catch what the threads say and dont click on them. Google translate is terrible at thread titles (works better for whole posts) as well.

[grumpygrady]

and you could build this to pull it
http://youtu.be/6w-ZnkeXI7c

[hippy]

huh, good ideal!