The instructions on this site tell you how to make a wheel hoe with an 8” oscillating stirrup blade. This tool is the most common and universally useful hoe attachment.
When I purchased a Glaser wheel hoe years ago, I paid dearly to get several different attachments with it. I have tried them all but the only one I really used was the 8" stirrup hoe.
Since developing the Planet Whizbang design, with the 8" hoe blade, I have come out with a 10" oscillating stirrup hoe attachment. In time, I may offer a 12"stirrup hoe for the Planet Whizbang.
I’m also working to develop an adapter fitting that allows the Whizbang to accept Glaser wheel hoe attachments, like the 3-tine cultivator and hiller-furrower.
But The Planet Whizbang wheel hoe is first and foremost a stirrup hoe weeder, and as such, it is an incredibly useful tool!