Thanks everyone for your comments. I'd love to see it made by others and how it turns out for you. I spent quite a few months going over the design so it would be as simple as possible. When I came up with this idea, I really liked it and didn't think I could get it any better. Hopefully somebody can take it from here and make it even better!!!
I really don't need to lift it for any reason. I did think about putting some loops on the top of it so I could pick it up with my forks, but decided against it. If I need to pick it up for some reason, I'll just use my loader bucket and pick it up wit the chain.
I put a little thought into where to mount the chains, but it's all theory. I don't know if wider would be better or not. My thinking was to distribute the load so that the iron was being pulled evenly. Too far apart would mean more pressure in the middle. Too close together would mean all the ends are creating more stress. I thought to get is as close to thirds as possible with the size of the blocks deciding the exact position.
I never thought about angeling it. I'm not sure if that would make it better or not. I like the way it cuts off bumps the way it is. It's very impressive how quickly and easily it works. If somebody tries it at an angle and says it works even better, I'll give it a try, but for now, I'm gonna stick with what works.
I can't say how well it will work in other soils. I do notice that the wetter the soil, the more it builds up and the heavier it gets. At 900 pounds, my 35hp tractor pulls it pretty easily. When there is allot of wet clay built up on top of it and in front of it, I can really notice the extra weight. Since this was an experiment, I was prepared to take off the blocks to get it where it would work the best. That never happened, but when I plant my grass seed, I'm planning on removing all the blocks to drag it over my soil. If that isn't enough weight, it's a simple thing to add a few blocks until I get it right. This is what I like so much about this design. It's very flexible.
I don't have any plans to paint it. Just using it for a few hours and the metal went from rust to nice an shiny. For what I have into it, and an expected life of ten years or more, I don't think paint will accomplish anything. I'll just let it rust and when it falls apart, make another. It only took a few hours to make it, so it's sort of a disposable thing.
I agree that the cutting edge on the angle iron will round off in time. I'm curious to see how long it takes. The other side of the drag is identical, except for the holes to attach the chain. A drill will change that in about five minutes. I can then pull it from the opposite side with that length of angle iron become the cutting edge. Another thought was to weld a bead of a hard welding rod over the edge. I'd have to check the rods to know which one to get. If the wear is an issue, the welding rod should be able to fix it.
Maybe somebody who builds one can do that and see if it helps, or makes difference?
I haven't tried it on my gravel driveway, and probably never will. I'm a big believer in leaving the gravel alone. Then when it needs repairing, buy enough rock to do it right and the leave it alone. My driveway is in great shape and I haven't touched it since the day it went down.
It really is night and day from my log drag. I've never had an I beam or railroad tie to drag behind my tractor, so don't know how well they work. I think the two things that really make a big deal in this is the amount of weight and the front edge being 90 degrees.
Thank you,
Eddie