Renze said:
Trust me, when you're done with it, you'd wish you kept the hydraulic parts and scrapped the rest (scrap price is good these days !!) and started from scratch.
In the end you'll have more work grinding and welding, re-aligning pins and bushings, than to weld up a stronger backhoe from a little more steel on the areas that have cracked on the original.
Just remember, welding is putting heat in the material, which warps the material and creates inner material tension: A backhoe that is totally welded up and through, has a lot of internal tension and will crack quicker than the original factory product, even if you reinforce it here and there.
By the way, are you welding cast iron parts there ?? Those will loose at least 40% of their strength after welding, because of the carbon in the cast iron...
You must like welding a lot
Renze,
I know you mean well, but --> sorry, you're wrong about the alignment. All the bushings line up just fine. When I brought the box, boom and pivot back from the machine shop they were mounted. All points moved like warm butter on hot pancakes. Or as they used to say, "slicker than deer guts on a door knob". No issue there, in fact that's why I did all of the welding BEFORE taking the parts in to be fitted with new bushings. Let the machine shop set the bushings and line hone if need be. Except for one bushing that was repaired incorrectly by a prior owner, no line honing was needed. Maybe I was lucky?
As to internal stress induced from differential cooling rates, maybe some but probably not enough to matter. I'd rather have a repaired steel piece than one with a crack in it. Wouldn't you? The only weakness around the welded areas I found was from the prior owners repairs where they failed to chip slag out after each pass. Encapsulated slag is not so strong.... Even at that, the hoe had lots of post repair hours - probably several thousand hours without problems. (outside of the pivot which was JUNK). The hour meter for the tractor was at 8500 and it was long ago broken. Actually, the meter works just the drive cable was broken. But the sun faded the exposed numbers very badly.
No cast Iron. All mild steel. Also, cast iron can be welded up and be just as strong as it was initially. (not that I can!). It takes an oven to pre-heat the metal to the exact temperature, weld hot, then a specific post heat and cool down. Done correctly the carbon is kept out of the grain boundaries and it winds up being good ductile material - not brittle. But, doing it correctly cost about $100 per crack.
BTDT - the ladder? It's one I bought to do home repairs back in 1984 or 85! The joints keep freezing up from me leaving it out in the rain, but a little oil and good as new. If you like wobbly ladders, it's great! I keep wanting to get a new one, but it just won't die!
I'll get some more pictures. I brought all of the tree hanging parts down and brought the boom, box and pivot in to the shop. By the way, moving a 600# freshly painted boom that is 1 foot longer than the door is wide is not all that simple! In fact, it took all day to get the parts in to the shop. Just knowing that one ill timed move can peel off the fresh paint makes my palms sweat! I did manage to get them onto a small trailer and set in the sun. The parts warmed up nicely - hopefully that will cure the paint up faster.
Yesterday I took one cylinder apart. It's the boom cylinder that would leak down slowly but steadily. It's a 4 1/2" diameter cylinder and should be a real bear to remove the rod, but it slid out pretty easy. The VEE packing is all age hardened. Unfortunately, the piston nut is on like crazy. A 4' cheater bar under my arm pit with me hanging from it and whacking the cheater with a 5# hand maul only managed to make my ears ring and armpit sting~! Ouch. I think my neighbor has a more powerful impact wrench to spin the 1 13/16 nut off.
jb
Edit to add pictures -----
The blob shaped reflection on the right side of the bucket is me. You can see the "industrial" hammered finish that the Corlar 2.8 PR primer gives. That stuff is THICK even when thinned to the recommended maximum.
