mini backhoe - collecting materials and ideas to make one

. I may never make one, but I am proceeding on the grounds that I will.

do not need a real backhoe. I can really get by with just using a shovel. But a mini backhoe that would be say 3 times as fast as just using a shove l appeals to me.

nearly the same as a some what bigger machine. The hydraulic cylinders and hydraulic valves are the major expense and they would not be significantly less for a tiny backhoe.

ith them. Most of the drawings are three dimensional showing all the hidde n lines. And most dimensions are in the text. And the pages all have the same title block. But I did not pay a lot so can not expect a lot.

from the local scrap yard. I am intending to put the engine, hydraulic pum p, filter and tank as a unit with quick disconnects. So I can remove that part and connect it to a log splitter or what ever. And hope to find a bo at trailer at the scrap yard to supply the wheels. I have already bought some 3/16 rectangular 4 by 3 inch tubing for the booms and chassis. All in pieces only 4 feet long, but I have a welder. I also have some cut offs o f 1 inch rod and some 1" bronze bushings.

a mini backhoe. Good sources for hydraulic cylinders and valves would be nice. The Surplus Center is already bookmarked. Things to avoid would be nice.

f using a hydraulic cylinder. It seems like that might be okay to do. May be have a plan on how to add power to swivel the boom if using my feet is t oo much work. Or maybe figure out a way to use car clutch and brake parts to swivel the boom. I am sure there will be comments on that idea.

There are ones that places such as harbor freight sells, called a Towable b ackhoe. It has a small engine powering the hydraulic system. These cost aro und 2k or so and work great. If your handy, you could probably build a smal l one. Google them and see the design, it might be exactly what you need.

I was thinking about a 3 valve block for the three cylinders used in digging and a 1 valve block for the boom swivel. So the one valve block could be mounted so it is actuated left and right rather than forward and aft. Even better might be a swivel valve that is operated by one's feet. Have not got my head around how to do that.

Dan =============================

You might consider if you would ever want a manual or hydraulic thumb, perhaps to lift stumps or boulders out of the hole. Rocks can be difficult to grip with chains.

-jsw

Am Mittwoch, 18. Oktober 2017 02:25:49 UTC+2 schrieb snipped-for-privacy@krl.org:

You're welcome to post your sketches here. I'll take a look (send me an e-m ail if I don't) and others can give their opinions too. You won't get a det ailed analysis, but we can likely help you to avoid the worst stress concen trations.

nders so one needs four valves. Are you saying use two two lever valve blo cks instead of a 4 valve block?

No, I mean you could get one of these (valve block on the right):

The two big levers operate four spool valves (the small levers in the centr e are to raise and lower the stabiliser legs). You can see the tops of the valve spools in the pictures.

That's my own pile of backhoe spares and the block is going onto my machine soon (to replace a leaky block), so it's not for sale, but they are often available from places which stock used backhoe parts. Two levers are a lot more comfortable to use than four levers.

The idea of the bell crank and foot pedals definitely sounds possible. One backhoe manufacturer used to have some arrangement like that, but it wasn't a manufacturer I'm familiar with. Might have been Case.

One last thing: if you're going to use the machine a lot, think about pivot wear. Use large bearing surfaces, lock the pin so that wear only occurs at one interface, and maybe consider replaceable bushes.

Nice project. Enjoy it!

Chris

It's strange, for a brake. There must have been some considerations that aren't obvious, in order to engineer something like that.

After all, leading-shoe drum brakes will give you all the mechanical "amplification" you want.

Appears to be a holdover from earlier farm tractor models. The bare tractor is only about 3200 lbs. With a loader and hoe it's nearly triple that. Did some searching yesterday and found several comments about the inadequacies of these brakes, and one mention of improving them by using oversize balls. Perhaps with disc friction material wear, the balls must move so far on the ramps that the drum rotates too much before the disc makes contact. I'll check it out next time the brake housings are off. Maybe the drum assembly can be shimmed a bit outboard.

I can see the attraction of using the vehicle's momentum to provide leverage, which works well on electric trailer brakes for example. But if the compound balls/ramp/disc thing was a good idea it should have been more popular.

My first thought was that it's very compact, which may have been the main idea. My second thought was that it's something from an era when we expected to make adjustments and replacements to mechanical parts for all kinds of things -- including cars.

Still, I'd like to know what the engineers were thinking. Overrunning clutches in most applications are either on or off, like a Bendix drive; the balls are either fully released, or locked on. There doubtless are exceptions, but, as I said, the mechanism is known to give trouble when parts wear.

At least you can see what's going on. A digital version would be a real headache. d8-)

Greetings Dan, My Case has what are called "Case Style" conrols. There are also "John Deere Style" controls. I have never used the Deere style controls but more than one person I have spoken to about backhoes has derided the Case style control. In fact, I was told that Case backhoes could be ordered new from the factory with Deere style controls. My case uses three levers and two foot pedals to control the how. As well as two levers for the outriggers. I think the Deere controls don't use the foot pedals. The foot pedals control the swing, the levers the the digging motions. I would advise against the foot pedal controls. This is because on my machine it is easy to step on the foot pedal when getting in and out of the seat. And this makes the boom swing fast. Which is dangerous. You should really take a close look at a backhoe control lever setup on a machine. Maybe your local heavy equipment rental place has one. Maybe talk to an operator or two. I rented a small excavator several years ago that used a joystick control. Much better. It took me almost no time to learn using the joystick. My Case controls were much harder to learn. They take more finesse. When you are digging the bottom of a ditch and it needs to be level the dipper has to be drawn backwards while at the same time it must be raised. It took me many hours to learn to do that operation even half way good. Finally, think about adding a thumb. My hoe doesn't have one but I got a cylinder recently to add one. I know, mission creep and all that. Cheers, Eric

I practice that whenever someone lets me try their machine, most recently a Kubota. Is there a control layout that makes it easier?

-jsw

On the one I used for about 150 hours a while back, all hand controls. Dipper control moves left and right for bucket tip. Boom control moves left and right for swing. That's if I remember right, because after a while it just becomes muscle memory. I'd used Case controls before and now after. No problem with either, although I'm occasionally still trying to move the Case levers sideways. :) Some will find either more instinctive than the other.

I find that the least dangerous thing on the 530. No handholds, no ROPS, vestigial fenders. Definitely made for an era when men were men, and sleepy heads lost limbs. :)

The Deere hoe I used was on a dozer. If you wanted to get out to be near the hoe, it was a long way around through the door. Much shorter to climb around the hoe controls, but one needs to take care to not snag a pant leg. Same with my skidsteer. No safeties at all. If you climb out with the bucket up you damned sure better not step on the lift pedal on your way out. They've engineered most of these risks out of modern machines. One friend's skidsteer has so many safeties it can be a pain sometimes. Another's needs its seat safety adjusted. He's heavier and has no issues. But when I'm in it and a bump lifts a bit of my weight off the seat, the brakes slam on. The halt bounces me back off the seat and then there's rounds two three and four before things settle down. Upside is that I can't remember the last time I felt the need to go on a carnival ride. :)

Am Mittwoch, 18. Oktober 2017 19:15:12 UTC+2 schrieb Jim Wilkins:

What layout does the Kubota use? I find the JCB cross-pattern levers pretty comfortable for this, but I'm not sure if they're better than other layouts.

Am Donnerstag, 19. Oktober 2017 12:49:30 UTC+2 schrieb Jim Wilkins:

Yes, the older JCB pattern is different. Lever motions at 45 degrees (into the corners).

You can find several different types of plans on Ebay for ten bucks a pop, too. Cutlists, patterns, assembly tips, etc. Pretty cool. I've wanted one of those for decades, too, but I've seldom had a use for one. Instead, I pulled a couple dozen shrubs/trees out using my cherry picker (engine hoist). The key: soak the ground 36 hours before digging, dig straight down a foot away from the shrub or small tree (larger roots can be hacked off with a 12" wood blade on a sawzall), chain the trunk or trunk bunch, then lift straight up with the hoist in 2T mode. Up they come in under half an hour apiece.

But I still want a backhoe, anti-tank missiles, artillery, space ship, and mass quantities of high explosives. After all, I'm a red-blooded American boy who knows how to blow off a finger or two. (right, Pete?) (No, no known uses for any of it/no plotting. ;) I'd settle for a gW vaporizing laser or disruptor for my yard to keep the riff raff, dogs, and zombies out.

IIRC Kubota uses Deere pattern (some were actually convertible "dual pattern" if memory searves correctly

All I want are the personal helicopter and jet pack promised to me by Popular Science magazine in the early 60s.

If this was a home economics NG, you would be right. But this is nominally a recreational metalworking NG, and making wrong economic

Making things when it makes no economic sense to do so, and keeping ridiculous old junk alive by fixing and making spare parts for it, is our equivalent of camping in a tent when you have a perfectly good house to sleep in.

Or spending a great deal of money to catch a few fish.

That's why I use my SB lathe to build my own fishing rods.

A $1,000 investment and ten or twenty hours of work will save you $200. Such a deal!