I have been playing around with the machine control on the bench and have hopes of making cheap row shutoffs for my corn planter someday.(at the pace I move through projects it won’t be ready for this year ) I am running the precision planting e-sets, and thanks to some inspirations from some of you (@WildBuckwheat), I would like to do something similar to what the Agleader surevac system does. From what I understand they use a solenoid to block vacuum to the holes in the seed disk right before they fall into the seed tube. This way the disk will stay primed with seed, and vacuum pressure stays more consistent.
It seems easy enough to copy but I’m sure I will have some challenges along the way to document. Initially, I thought that a cheap solenoid be very easy to do this with, but I was concerned that it would get very hot if engaged for a longer period of time like planting along a field edge and cause damage to something.
My current thinking is that I can use a car door lock actuator to do the same thing and not have this concern and I have ordered this one off of Amazon to try for just under $10 usd!
It is similar to what @bitfieldfarm has on his APV seeder and I think I can do the same polarity swapping with my relay board to control it. I may need to 3d print something to block the holes in the seed disk with and to create a way to mount it.
Just wanted to throw the idea out there to see if I am thinking along the right lines or if I am missing something simple that would be a better approach. As always, I appreciate the input/ideas/help from all of you, this is such a cool community to be apart of!
Very interesting. I haven’t been around those. I’m only familiar with sure stop chain drive clutches from agleader. The power lock is worth a try for $10. Will need to test it’s ability to hold without power. It may burn up if power is always applied. I could be wrong, but that’s putting constant power to a locked rotor motor. Unless I don’t understand it fully.
Might b able to pulse it in and out and achieve desired result. It probably will be tricky to get correct tension to plate. Nothing you can’t handle.
Thank you all! Those are all good points. I do think I would have to figure out a way to cut the power to keep it from burning up and I’ll have to see what the holding power is like as well. It also might not even fit when I get it here, I’m not completely certain on the dimensions. I’ll try to update when I get it here and try it. Hard to go wrong for 10 dollars.
I wasn’t able to find any information on what type of solenoid Agleader uses. Should I even be concerned about the heat from a cheaper solenoid?
I know servo motors would also be a potential cheap option but I thought it would be simpler to have something that was easier to swap in and out without having to calibrate the position. I’ll have to do some more thinking for any other ideas…
I may end up eventually getting a commercial solution like the Surestop clutches, I do like that system and it seems it would be more accurate and easy to use. There would just be something really satisfying about finding a reliable cheap solution
The door lock actuators that I’ve taken apart were a Mabuchi 130 size motor with a gear reduction and rack and pinion drive. They have next to no holding power when not energized and are not meant to be constantly energized.
I think with some kind of 3d printed toggle mechanism you could have a spring that holds the actuator in the extended or retracted position, and a momentary burst of power will energize the motor to move through the toggle? Or use an H bridge and send the motor a very low duty to have a little bit of holding force without overheating?
Not giving into buying commercial is what AOG is all about! You can achieve anything you set your mind to.
So if I have this correct, the plate is there while planting. Pull it away to stop planting? Do you have a pic of a normal unit that plants all the time? I picture a spring extend, power retract solenoid. Power to not plant is best. I may have operation of vac backwards.
I don’t have a great picture of a normal one right now, but if I am thinking about it right, the solenoid is on the back side of the seed plate (opposite the seed) where the vacuum is pulling from. So then it is away from the plate while planting, and against it to break the vacuum and stop planting.
You are absolutely correct. I got it this morning and though it is a nice small size, there is almost no holding power. I like the toggle idea so I’ll have to see if I can dream up some sort of simple mechanism to try.
) I am running the precision planting e-sets, and thanks to some inspirations from some of you (@WildBuckwheat), I would like to do something similar to what the Agleader surevac system does. From what I understand they use a solenoid to block vacuum to the holes in the seed disk right before they fall into the seed tube. This way the disk will stay primed with seed, and vacuum pressure stays more consistent.
