Opinions on box blade modifications

   / Opinions on box blade modifications #1  

canoetrpr

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I'm ready to take on my first implement modification project having gotten to the point where I think I can weld well enough to do something simple.

My box blade is the kind that has a hinged rear blade and I want to set it up so that the rear blade could be fixed optionally. Others have noted that a fixed rear blade works well for final grading... figured I might as well have the option.

There are some box blades that come from the factory so that the rear blade can be adjusted to either be fixed or not. I've never seen one like this. If you have one, can you describe to me what the mechanism is that either locks the blade in place or allows it to move?

I have attached a picture of my box blade. My current thought is to weld a 3/8" plate to each side so that it over hangs by a couple inches off the rear. Then I would drill 2 3/4" holes into each of these side overhangs through which I can insert two 3/4" pins.

The pins alone might do the trick but the rear blade is not shaped exactly straight (unless one 3/4" pin would do it).

Thought was to cut another 3/8 piece for each side which would be loose and would fit up against the rear blade. It would also have two holes to align with the welded on side plate, through which the 3/4" pins would go.

Not sure if one 3/8" piece on each side supported by two 3/4" pins will adequately hold the rear blade in place.

Your thoughts are appreciated.

P.S. Rob - bet you will have some good ideas on this one. You put me up to considering rigging something up to fix the rear blade when necessary :)
 
   / Opinions on box blade modifications
  • Thread Starter
#2  
Oops.. here's the blade.
 

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   / Opinions on box blade modifications #4  
buy some 3/8" thick by 2" angle iron. Bolt it on the edges so it holds the edge down. The bolts will go from outside to inside. Inside the box, weld nuts so you only have to loosen / tighten from the outside.

Align the angle. Clamp it in place. Drill the holes thru the angle and the box. Remove the angle. Grind off the paint on the inside. Assemble the angle with bolts & nuts. Protect the bolts so the weld slag doesn't freeze them. Weld the nuts. wire brush off the burnt paint, prime, paint, photo and admire.
 
   / Opinions on box blade modifications #5  
john_bud said:
buy some 3/8" thick by 2" angle iron. Bolt it on the edges so it holds the edge down. The bolts will go from outside to inside. Inside the box, weld nuts so you only have to loosen / tighten from the outside.

Align the angle. Clamp it in place. Drill the holes thru the angle and the box. Remove the angle. Grind off the paint on the inside. Assemble the angle with bolts & nuts. Protect the bolts so the weld slag doesn't freeze them. Weld the nuts. wire brush off the burnt paint, prime, paint, photo and admire.

I have a similar blade and this was almost exactly my thought. I wasn't going to weld the nut on the inside though if it was at all possible to get to the area to remove it. On my blade it might take 2 1/2" or 3" angle to make the dimensions work.
 
   / Opinions on box blade modifications
  • Thread Starter
#6  
john_bud - glad I came and asked here!

In bed right not but I will check the blade tomorrow. Pretty sure that area I would have to drill would not be terribly accessible from the inside of the box blade even to weld on nuts.

That said, I'm thinking of a simple modification to your idea. Welding on a 3/8" piece at each end jutting out of the back two to three inches, so that I have something to drill that I can access. Bolting on the angle iron except reverse to the way I'd have to do it as per your description.

Now that I think about it, I have some 1/4" thick angle iron about 3-4" sitting in the shop that I picked up at a scrap yard to practise welding. I think it might work perfectly if 1/4" won't be too weak. If it is - well it was scrap anyway, and I'll go replace it with something stiffer when it bends up!

Thanks again!
 
   / Opinions on box blade modifications
  • Thread Starter
#7  
john_bud - silly question from a welding newbie. How does one "protect the bolts so the weld slag won't freeze them"?
 
   / Opinions on box blade modifications #8  
canoetrpr said:
john_bud - glad I came and asked here!

In bed right not but I will check the blade tomorrow. Pretty sure that area I would have to drill would not be terribly accessible from the inside of the box blade even to weld on nuts.

If you use loose nuts you access them from the bottom. Just put it on the 3 point and lift it up. If you want to weld the nuts on then set the blade on its endplate


canoetrpr said:
john_bud - silly question from a welding newbie. How does one "protect the bolts so the weld slag won't freeze them"?

Put a bolt in them that sits flush with the nut face before you start welding. Remove it before the nut cools completely.

That said, I think you'll be disappointed with nuts welded on. The welding heat turns your nice grade 5 or grade 8 nuts into something that's softer than hardware grade fasteners...
 
   / Opinions on box blade modifications
  • Thread Starter
#9  
Looks like welding nuts or putting hole in the side plate won't work out for me. The area is inaccessible even from the bottom. This is the area between the two (front and rear) blades and there isn't a way to get to it on the other side.

However the modification to john_bud's idea will work. I'll weld up a 6" by 3" 3/8" plate so that 3"x3" juts out behind the side plate. I'll drill that and hook the angle iron to that.

Thanks!
 
   / Opinions on box blade modifications #10  
Glad to help.
 
 
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