This is a work in prgress and I will upload files As and when I have them .

All the files I have created / Modified to make my RC lawnmower AKA THE TURFINATOR II. Ive not split the parts into printable sized chunks because my slicer wont let me export them as a split file. split / orient them yourself according to your printer.

SAFETY!!! THIS PROJECT CONTAINS A FAST SPINNING BLADE AND LITHIUM BATTERIES PLEASE USE CAUTION AND BE SENSIBLE ,I have replaced the power button from the hoverboard with a large one that stands pround so it can be turned off quicker and easier, i have also installed a XT90 "loop key" which will cut power to everything in the case of an emergency which is also useful for winter storage. since the electronics will still draw a little power even when off
Finally MAKE SURE your transmitter has a failsafe function and it IS SET UP to stop the mower in the event of power/signal loss, The last thing you want is for the mower to go full speed because your batteries went dead. its not massively fast but its fast enough to chop a flowerbed into mulch before i have time to get to it. SAFETY!!!

This is obviously not a begginer project as just the cover alone requires a fairly well tuned printer to get half decent results on the curves, You also need to work with dangerous lithium batteries, some woodworking, adjusting Firmware ,soldering etc etc etc

Grass Skirt
Obviously NEEDS to be strong With excellent impact resistace anyone who has ever used a lawnmower will know they can and WILL launch small stones etc at very fast speeds straight at your feet/legs. Lots of perimeters good infil and possibly an upgrade in materials , Mine is holding up ok in PLA and 0.8m nozzle 3 perimeters but fully expect to upgrade eventually.

Cover
Doesnt need to be especially sprong as its only cosmetics and to keep the dust / grass out of the delicate electronics. I used the zero top/bottom layers and tuned the infil to produce the air grill on the cover top..

Caster bracket.
Needs to be as stong as you can print it Ive printed mine at almost solid and it still feels marginal. I may redesign at some point,

Bearing housing
Designed to completely house 2x skateboard style bearings but Mine failed when I attempted to pause and insert the bearings as the fit was too tight , Rather then starting again I just press fitted the bearings and it has worked just fine as is.

Base ,
Ive uploaded it JUST to give you an idea of what to build , Ive not modeled in any of the screw holes as I just marked them straight from the components. I cant see any reason why it couldnt be printed but you would need to add in all the mounting holes yourself and I cant guarentee anything would fit as I have not personally used it nor did I get my plywood CNCed from it.

Electronics motors etc .
I used the a STM based Hoverboard motherboard with custom firmwire to allow RC control with a Cheap Mini 2.4GHz Remote and receiver from Ali-express (https://github.com/EFeru/hoverboard-firmware-hack-FOC/wiki/Variant-PWM)
The Grass cutting motor and blade are from a Ozito PXCLMK-218U which seem to be readily avaible and used by a few different manufacturers , I would like to upgrade to brushless at some point.
The wheel motors are from the same hoverboard and are availible as spares from various sources with custom printed "tyres". I made the tyres as one file and them the motor as another file and subtracted the motor file in my slicer This was easier for me as I could adjust the size of the tyre without adjusting the fit on the motor.
Ive uploaded my .bin file which you could in theory just write onto the HB motherboard although I STRONGLY suggest you compile your own and familiarise yourself with the parameters so you can change how it behaves/handles. No guarentee this this firmware will work with YOUR specific hardware.

Battery
I got lucky with a used 36v Battery from those popular e-scooters which fits nicely inside and provides more then enough runtime for my fairly small lawn, Mine came with damaged moutning tabs so I cut them off and made my own mounting brackets.

Various screws switches etc according to preferances
I prefer XT60 connectors as thats what came fitted to the motherboard and what I have in stock I have also since fitted a Remote switch for the cutter motor for convinience , you could use a RC controlled Relay if you have a extra channel on your remote/receiver or just use a manual switch as I did for testing.Various spacers Etc which are so simple I didnt bother uploading them.

Frount castor wheel I used luckyxav's wheel many thanks for that (https://www.thingiverse.com/thing:2066953)

I have uploaded my switch plate but you may want to model/make your own to fit whatever hardware you are using. In mine I have
4mm hole for a peice of teflon tube which the antenna fits into to get it up and out of the way of all the interferance
22mm hole for the large switch
Cut-out for the XT90 loop key which I still had to file to fit
Cut out for the battery guage
12mm hole for the charging connector which came with the Hoverboard
It was quite a challange to get it all to fit and I wished Id modeled in a larger cutout for the switch plate but I dont fancy re-printing it

I didnt make this for profit or specifically for others to print but if you did find this useful then you could give me a tip towards the cost of filament , Making a big project like this usually costs me at least a roll of filament in wasted parts which needed adjusting and then re-printing. Not counting the hours of modeling etc.

Update 02/06/2024. This Mower has now been fully tested and has mowed my lawn a few times now with great results . I occasionally have to manually move it when it gets stuck in a hole but thats as much a fault of my crappy uneven lawn as the mower. The grass skirt has provn itself to be JUST adequate as one of my children left a sizable stone on the lawn it smashed a quarter up BUT NOT THROUGH, the rock was safely contained and the grass skirt was intact enough to continue and finish mowing the lawn although I have reprinted it more sturdy and in PETG as I doubt it would survive a second hit.
The castor bracket has also cracked but is still working fine I will upload the new version as soon as Ive confirmed it fits ok.

Update 28/04/2024 Ive redesigned and reuploaded the castor bracket again, This is the only part Im having issues with so Ive adjusted the angles and thickened up the walls. Ive tried printing in PLA, PETG, ABS and even nylon and current testing a "tough" resin one ,Im seriously considering making a metal one.
Im also working on a skirt with a opening to eject the grass clipping a) this would allow a collection system , Which I am personaly not interested in but you could develop somthing b) seems to be much easier on the motor and it doesnt bog down in long grass as much . Im having difficulty getting the clippings (or anything else) to eject in a safe direction and not clog up.

Creality

Ender 3

Everything printed in bog standard whatever was cheapest at the time on Ebay PLA

Use print settings according to your printers tuning to get get best results.

I had to split the cover into quarters and print upright but undoubtedly would have got better results if I had a printer big enough to print them laying flat, best results would have been a printer big enough to print it in one peice

FOR THE GRASS SKIRT MAKE IT STRONG!!! at least 2mm walls I split it into 4 again with a screw hole in the middle of each peice and printed with the flat side on the bed 2 at a time , I probably could have squeezed 3 on the bed but didnt seem worth the bother. MAKE IT STRONG!!

Main wheels I think I went with 4 perimeters just to give some room for them to wear they dont need to be massivly strong.

Castor bracket I went with 3 perimeters which means it is about 90% solid and still doesn't feel as sturdy as I would like , it is however working ok so far.

Everything else standard print settings/ whatever feels right , Nothing apart from the grass skirt needs any particular stregnth.