Gear Driven Hydraulic Scarifier System on Boxblade

[3RRL]

I converted my 7' Howse Boxblade during my vacation so that it now has a hydraulic system to raise and lower the scarifiers. I got the idea from other threads I read here and figured it would be a fun project.

I'll show a lot of pictures (again) to show the new "look" first and then the process of changing it. This project took quite a lot of machining and a little design work to retro-fit everything so it would work properly. Lucky, I was able to do most of the component machining in my shop at home, but much of the welding, fitting and final assembly had to be done at my rural property. My biggest concern was the proper line up of all the leader pin guides, the gears, shaft and racks. I had no way to fixture or bore holes at the property to guarantee perfect association between them.

Here is the first picture of the finished hydraulic system on the boxblade. Notice the handle to move the system manually in the event of a blown hose or cylinder. The handle screws off the end that stays on the shaft and I'll store it in one of the tool boxes on the tractor. All components and gears are keyed to the shaft. Notice the pins that guide the scarifier lift blocks up and down. Also notice that each gear/rack assembly is enclosed to keep the appropriate pitch diameter relationship. Also the clearance through the large black brackets for the system to work.

I also added supports for the lift pins now that the boxblade nears 1,000 lbs in weight. And finally supports around the sides and back of each scarifier to add strength and reduce bending and breaking.

 

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This is a picture from the rear that shows each of the gear/rack assemblies and the center mount that supports the hydraulic cylinder. The 2 outer scarifier lift blocks hold 2 scarifiers and the center lift block holds 3. The 2 outer ones are driven by one set gear/racks and the center one by 2 sets. That is also where the hydralic cylinder racks (2 of them) drive all the gears.

 

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Now to show how I started with this concept sketch.

 

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Which I detailed out on the CAD system to look like this.

 

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Of course I soon learned that the original boxblade was not EXACTLY symmetrical from one side to the other and I might experience having to compensate for a few thousands of an inch... boy was I ever wrong. There were some areas that were over a ¼" off!!!
Here is the original 7' Howse boxblade when it was new.

 

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It didn't look bad then but I got tired of messing with adjusting the scarifiers up and down and whatever...
So here it is on my shiny Kama 554. Notice in this picture I put my code name on for you guys.

 

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Here's a close up of the conversion mounted to the tractor....hope you're not getting tired of seeing all this?

 

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Before I start showing some of the building process here is another one of it from the side, lifted up. This is where you can see the hydraulic lines and also the Top-N-Tilt cylinder with my indicator markings on it.

 

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Before I go any farther, I wanted you guys to know how supportive my wife Loretta was throughout this whole "project" thing. Plus, she helped me assemble the thing at the property and as usual, painted everything for me.
This is what my garage looked like after finding all the scrap remnants and other stuff to make everything.

 

[3RRL]

As you can see from that last picture, there is a right angle gear box in that pile of junk that will someday become part of my "gutter cutter" project.
Anyway, this picture shows the lift bars that carry the scarifiers and the guide pins and retaining pins I made. You can see that the center bar is longer and carries 3 scarifiers. Those are held in place with dowels and then there are pockets cut to hold gibs in place. This is because I could not use a pull-out pin in the center, plus this long center bar is covered up by the black brackets. All the lift bars have milled slots for the scarifiers to slip though.