while using it we had the shaft break, dont have it mounted in the best way just yet but a seed tried to bind an that cause it to pull slack in the chain an pulled the sprocket out of line just enough for the chain to start climbing on the top of the teeth instead of between an that was the force that ended up breaking the shaft, but it bent both bolts first then broke. ive added a v5 and v5.1 to the files an this should fix the issue along with the brush to help keep only a single seed in the seed wheel as it trys to feed through. im going to use v5.1 but im adding both for those who want to try it, but if u have the ablitily to make the shaft out of metal id suggest that option first an thats what im working toward just trying to get all the tools i need to make that happen so until then the printed one works. also with this version being bigger u can actually use the thread inserts like i did on the rest of the parts. the side of the shaft the sprocket bolts to is the only one that didnt use thread inserts cause of lack of space so now that shouldn't be an issue.

after using it the newer seed wheel seems to try to hold 2 seeds instead of just one as it passes through the hopper an it can bind the wheel, alot of the professionally made used a little brush or section of brissels right b4 the seed would pass through the divider section helping it only allowing a single seed or clear what would normally bind the seed wheel. so that was the solution i went with, just used a old paint brush an glued it in place.
i come up with this for my dad to keep him from having to plant the seeds by hand. he only uses it for green beans or half runners i think they are called. i took the 3d printed parts an mounted them to a frame i put together from old scrap metal. bicycle rear wheel the crank sprocket for the drive gear for the hopper but it could be done from whatever youd like, searching for seed hopper or seed planter will show how some of the professionally made planters work an the frames would be easily recreated i was just trying to make use of old scrap but i made the mounting parts so they could be used in different ways in hopes it would fit anything someone created. i used old metal tubes i had laying around so it might not have been the best option, again i was just using scrape metal i had on hand but if you was willing to spend alittle money u could build the frame just like the manufactured ones.

i printed alot of the bigger parts with a .4 nozzle at .28 layer heights to keep the print times down, smaller parts i used .2 but whatever works best for you is what i would suggest. all parts printed in pla an i used brass inserts in all of the bolt holes except for the ones on the shaft due to lack of space.the shaft could be easily made from a bolt if u have one the correct diameter an just grind a flat spot for the seed wheel.