The only issues I've had with my (greater than 5' wide) Caroni and LandPride RFM's were with the wheel yoke shanks bending. Both brands were only problematic in the 6' and greater widths. I assume it is due to the weight. The way the decks are made and the height at which I cut the grass means that there's a lot of shank held below the support via the spacers. Cruising along and running into a tree root, or swinging a turn so the wheel impacts the edge of paving translates into a lot of leverage. I've bent shanks over the 30-ish years I've had RFM's. Straightening them hasn't seemed to affect their strength. My first successful attempts were (mis)using an old hydraulic bender without the bending shoes. A bit cumbersome, but OK:
Next was a rig that was made to fit into a receiver hitch. It is a 1" plate with 3" channel irons. There is an oversized hole for the shank, and the shank protruded out the rear. Sorry, no pics but it was a beast to use. A piece of heavy wall pipe slipped over the shank and with a prop under the Rube Goldberg assembly it was solid enough to do the job. It was even more cumbersome than the old hydraulic bender, so as time passed there were different thoughts about both repairs and possible prevention.
Spending some quality time with the tools and various scraps produced what is so far the best solution. There were parts left over from a previous project of taking two "challenged" 5' Caroni decks and making one nicer deck. Having those leftover parts allowed the new supports to be fabbed without taking the 7-1/2' RFM out of service during the mowing season. I had a few pieces of 2x2x1/4 galvanized steel square tube that would be good for the horizontal parts of the supports. For the round vertical 1" ID tubes that the shanks pass through, I plasma'd a set off the old donor deck. Unfortunately, my mag drill only goes to 1-1/4", so I used a 1-3/8" hole saw in the drill press to make clearance holes for the vertical tubes to be welded in. The new mounting method reduces the amount of shank below the support to the thickness of one washer by having the horizontal 2x2 square tube 1-1/2" above the top of the mower deck..
The existing tapped holes for the grease zerks in the round tubes fell about 1/2 in the one wall of the square tube, so they needed new holes. That was a good time to make a drilling jig that I thought about many times. It's a simple piece of angle iron with a flat bar welded to the outside corner. The flat bar is clamped in the drill press vise. A small bit is chucked up and lowered into the angle. When the bit is at the bottom of the V, the vise is fastened to the table. Laying a pipe in the V brings round tube to be drilled TDC with whatever diameter bit wanted. A smaller bit for the setup makes it easier to see when it's at the right spot. I'd bet Wifey wouldn't miss a knitting needle if I cut one down for a "pointer".
Straightening the shanks was done by modifying the shop-made tool mentioned earlier. It involved drilling a hole that fit the 1" shanks better and reworking the 3" channel iron. Excess length of the channel irons was removed and welded to the bottom to create a space that worked well with the 8T jack at hand. Here's the tool being modified. The new clean hole holds the shank better than the original oversized hole. All stresses are within the tool itself now. I clamp it to my welding table with a Visegrip clamp just so it doesn't get knocked over. The one "before" pic is a sample of what I was dealing with. With leftover donor parts there is a spare set of yokes ready if the need arises.
Next was a rig that was made to fit into a receiver hitch. It is a 1" plate with 3" channel irons. There is an oversized hole for the shank, and the shank protruded out the rear. Sorry, no pics but it was a beast to use. A piece of heavy wall pipe slipped over the shank and with a prop under the Rube Goldberg assembly it was solid enough to do the job. It was even more cumbersome than the old hydraulic bender, so as time passed there were different thoughts about both repairs and possible prevention.
Spending some quality time with the tools and various scraps produced what is so far the best solution. There were parts left over from a previous project of taking two "challenged" 5' Caroni decks and making one nicer deck. Having those leftover parts allowed the new supports to be fabbed without taking the 7-1/2' RFM out of service during the mowing season. I had a few pieces of 2x2x1/4 galvanized steel square tube that would be good for the horizontal parts of the supports. For the round vertical 1" ID tubes that the shanks pass through, I plasma'd a set off the old donor deck. Unfortunately, my mag drill only goes to 1-1/4", so I used a 1-3/8" hole saw in the drill press to make clearance holes for the vertical tubes to be welded in. The new mounting method reduces the amount of shank below the support to the thickness of one washer by having the horizontal 2x2 square tube 1-1/2" above the top of the mower deck..
The existing tapped holes for the grease zerks in the round tubes fell about 1/2 in the one wall of the square tube, so they needed new holes. That was a good time to make a drilling jig that I thought about many times. It's a simple piece of angle iron with a flat bar welded to the outside corner. The flat bar is clamped in the drill press vise. A small bit is chucked up and lowered into the angle. When the bit is at the bottom of the V, the vise is fastened to the table. Laying a pipe in the V brings round tube to be drilled TDC with whatever diameter bit wanted. A smaller bit for the setup makes it easier to see when it's at the right spot. I'd bet Wifey wouldn't miss a knitting needle if I cut one down for a "pointer".
Straightening the shanks was done by modifying the shop-made tool mentioned earlier. It involved drilling a hole that fit the 1" shanks better and reworking the 3" channel iron. Excess length of the channel irons was removed and welded to the bottom to create a space that worked well with the 8T jack at hand. Here's the tool being modified. The new clean hole holds the shank better than the original oversized hole. All stresses are within the tool itself now. I clamp it to my welding table with a Visegrip clamp just so it doesn't get knocked over. The one "before" pic is a sample of what I was dealing with. With leftover donor parts there is a spare set of yokes ready if the need arises.
