backhoe from scratch and scrap

[Crusarius]

Does the head on your mill swivel? mine will swivel front to back or left to right. Makes doing that chamfer much easier. That is how I made a set of V-blocks.

yea, thats usually my idea to.

It does swivel, but it takes a lot of fiddling to get it back where it's supposed to be. I didn't need accuracy or precision for this so I didn't want to disturb that head.

[Crusarius]

I bought one of those dual dial indicators for just such an occasion. It works very well. Biggest issue I have is all the bolts and things that need to be loosened then tightened then rotated. it is a decent amount of work to do. I think I am just going to get some countersink bits and use those for beveling.

[grouch]

Bucket brackets.


Gloves, me and the steel got cooked before those bevels were filled.


A line of 7018 slag in the undercut.


Looking better.


Part of why I had so much trouble with these is that I kept trying to weld as if the two pieces were equal.


Note how much the 3/8 inch plate is built up here with weld. That's not the best substitute for good welding technique.


That's glare this time, not slag.






Warpage is pretty obvious in this photo. The 3/8 inch rebar in the background shows that it was more restrained than the one in the foreground.
No telling how much I weakened that back plate around those welds.

[grouch]

Bucket brackets.


Oops. Only one pin goes in now.


The pin is 1-1/4 inch in diameter.


That can't be pounded in without damaging something.


I've added white lines to show the upper edges of the 3/8 inch rebar.


It needs to put its foot down on that plate.


It's out of focus, but you can see the back rebar touching the plate while the near one is above the plate.


The pin appears to be parallel to the plate and the bracket looks perpendicular, but everything above that is just plain wonkified.


View from the back.


It's easy to see what gave when things started shrinking.


Compare the offset of the hole to the pin with the offset of the rebar to the plate.

[grouch]

Bucket brackets.


Tack weld the back rebar to the plate...


and one end of the front rebar.


Prep for welding nothing to the inside.


You have to have a wide space to weld nothing to something.


A whole bunch of nothing welded inside.


That foot is almost down.






I can live with that sliver of daylight.

[Crusarius]

I need to remember the 3/8 rebar for holding stuff in place. its cheap light and flexible when you need it to be.

[grouch]

Dipper.


My dipper is too fat.


I know this has something to do with the taper. This is why my CAD drawings were always out of sync with reality.


My straight line cuts with oxy-acetylene were usually more like drunken paths with drool.


Plasma and a straight edge are much easier.


Other side. Note the piece curving away. Hot rolled steel has stresses built in; cutting lets 'em out.


Another view of the same cut.


A strange shark?


None of the stuff that was cut out was helping with the dipper's function.


It's a big mouth.
Black grease smeared on the DOM pivots keeps rust at bay.


Flop the fish on its back to prep for welding.


Very little slag to remove from the cuts. Note the curvature of that flap.


Clamps close the mouth.


Gap at the hinge looks to be about 3/32 inch.


Gap at the other end looks to be about 1/16 inch.


1/8 inch 6011 rod. Note tack on the left and the cooked grease above.


Closer view. Somebody beat it up with a chipping hammer.


Skinnier dipper, but it needs a lot more space.


Without that gap, the bucket could never curl to less than 90 degrees relative to the dipper.

[grouch]

Boom end.


The end of the boom needs to be closed but I don't want to try bending those curved corners.






Quick, Robin! To the Bat-Mo-Boom!


Oops. The white lines reveal the secret plan.


The weld drools a little.


Vertical up 6011 rod filling the gap in the darkness in the left of the photo.


Still in shadow; view from above.


All filled.








End closed.


After cleanup with a needle scaler.


After grinding some edges smooth. This is not just for looks; it improves the ability of paint to stick and it makes it a little less carnivorous when greasing or doing other work on it.


Not quite a work of art, but the sucker is closed up.

[grouch]

Boom other end.


This is the end with the hinge for the dipper stick.


Two magnets hold the plate flush with the end for tacking in place.


6011 again. Fat, ugly welds.

[grouch]

Dipper ends.


Good place for wasps and mud. This is the bucket end of the dipper.




Cuts and bend are a little raggedy, but they'll do.




The hammer responsible for that fancy edge is in the lower left of the photo.


Welded with 6011 rod. Photo shows the aftermath of a needle scaler.




Almost all the grease has been cooked off.


The big end of the dipper.

[grouch]

Bucket cylinder mount boxing.


The two pieces of 1/2 inch steel holding the DOM tube just didn't look right. Boxed in with 3/16 inch steel left over from the bucket buttectomy.


It at least looks stronger, now.

[gww]

Grouch

I bet your local welding rod supplier just loves you.
Cheers
gww

[grouch]

I shopped around for rods. Surprisingly, the best deal for price and dryness of the rods for me was a TSC store about 45 minutes away. I'm not sure how many 10 lb and 25 lb boxes I bought there. About 20 pounds came from the nearest welding supply place -- about 1 hour away -- but they burned inconsistently.

[Kbeitz]

I buy my rods from the Amish store. I use 80T AC Plus

[grouch]

Pins and retainers.


Used a plywood template to cut these out with a plasma cutter. Too much slag -- either cranked up too high or moving too slow.


That rusty, round table rotates.

[grouch]

Bucket linkage.


Putting the dogbone together.


Undercut above and drooling below.




DOM tubing, 2 inch OD and bored for 1-1/4 inch pins.

[Crusarius]

I like the rotating table. One of these days I may actually build one.

[grouch]

I got this one from a farm auction. It's just a pipe with a close fit over a steel rod and a bearing at the bottom.

[Crusarius]

power window motor with a computer power supply and a potentiometer be real nice add to that table

[Hilltop366]

I was thinking a sewing machine motor and foot pedal control.

[Crusarius]

That is a much better idea The foot control would be key. Bet you could use the foot control on the window motor.

[grouch]

Either way would beat having to turn the table with one hand while the other welds.

It wouldn't need much variation in speed to be effective. It's not like you're going to be making spin art with paint.

Someone built this little table from scrap pieces. The center column runs all the way to the ridiculously underbuilt base, so a motor and belt could rest on that base and be protected. Putting the motor up close to the underside of the table, you might need extra weight on the base, but that would not be a bad thing either.

[grouch]

Boxing the dogbone.


The sides are 1/2 inch thick, but it still didn't look strong enough to me. 3/16 inch thick pieces used to box it in.


Only needed a little curvature to fit.


Scrap pieces used to prop it up at convenient angles for welding.


Don't look at that blob at the bottom. It must've been defective steel. I'd never burn a hole when welding two different thicknesses. No sir, not me. Defective steel. Let's move along.


See? Perfect ... ok, moving again...


It's an artistic rendering of giant woolly worms square dancing.


Installed.




Clevis and come-along needed because that bucket is not a featherweight.

[Crusarius]

Oh there is something defective alright

One day I really want to build something like this. Mostly for the pure fun and entertainment. I was thinking a bulldozer though.

[grouch]

It has been fun. The fact that I didn't have to have it kept the pressure off so that I could enjoy working out each problem and building each part. That's also why it took so long -- it kept getting superceded by things that simply had to be done. For a while, I thought it would be up to my heirs to finish it. :D