making a subframe for my 01 John Deere 4300 and Prairie Dog backhoe attachment

[mjncad]

a new member to this community.thinking of building a mini backhoe,for a power tiller of 12bhp.so i require some detailed free backhoe plans.please help with any valuable guidance and plans if any.thank you.
email kairala27@rediffmail.com.

Welcome to TBN.

However, as a designer I get tired of people asking for free plans. There is a lot of work that goes into the design, engineering, documentation, and testing of products to just give away that intellectual property without compensation.

Best of luck in finding free plans of a backhoe. I do suggest you search TBN for various implements designed by the members of this community. Those threads can provide valuable insight for you to design a backhoe to fit your needs.

 

[dfkrug]

There is a lot of work that goes into the design, engineering,
documentation, and testing of products to just give away that intellectual property without
compensation.

I agree, and the actual experience of building the item in the plans has even more
value.

I was happy to pay $99 for my CADDigger plans years ago (the blue machine in my
avatar). There is certainly value to not having to make every mistake the designer did
in his first build. As it was, there were plenty of hours spent in the fabrication work
that I did. (And some modifications, of course.)

Sometimes, I just don't get it when someone insists on going it alone when there
are some good plans out there at reasonable prices.

"Genius is 1% inspiration, and 99% perspiration." T.A.E.

 

[retiredmgn]

Very nice work. Could you explain how the backhoe is attached to the tractor? One of your pictures shows 3 bolts. What else holds it on? Never had a backhoe.

 

[dfkrug]

I have been using the tractor to move some rocks and log sections
around my place. I always use these machines for several hours
at least to iron out any problems and make adjustments.

I had to replace 3 zerks that broke, and I tracked down a hydraulic
leak or two. New equipment often has hyd leaks since there are many
hoses and fittings, and not all of them are tight.

I also had a tiny tiny pinhole leak in one of the swing cylinders. I
thought it was a hose leaking, since the location was hard to see,
and it only leaked when swinging one way. Well, here it is. You
can see where it is from the paint that came off. It is so small that
my smallest wire can not go into it. It puts out quite a spray.

To fix it, I removed the cyl, drained the oil, and drilled a divot with
a 1/4" drill bit about 3/16" deep. The divot was aligned with the pinhole
and did not go all the way thru the cyl wall. I then put a bit of acetone
in the divot to dissolve the remaining oil. Oil will cause porosity
in the weld I am going to do to plug the hole. You can also burn out
the hyd oil with a torch, but I did not want to heat the cyl more than
I had to. The weld took a second, and worked great.

The original weld seemed to be done by a machine (perfectly straight),
and the pinhole was right at the start/stop point in the bead.

I have done a video of the tractor, and I will post it next.

 

[Luremaker]

Thanks for another great build Dave. I do have a question about the saddle. I suppose the saddle will take much of the weight and other forces when the backhoe is being used. When I compare your saddle to the saddle on the Kubota or Woods subframes they seem much beefier. Do you think this may be a weak spot after some heavy use of the hoe. I've attached a picture of the saddle on one of Kubota's subframes.

 

[mjncad]

I agree, and the actual experience of building the item in the plans has even more
value.

Exactly! Depending on the item, the design and engineering time can equal or exceed the fabrication time.

 

[dfkrug]

I do have a question about the saddle. I suppose the saddle will take much
of the weight and other forces when the backhoe is being used. When I compare your saddle to the saddle
on the Kubota or Woods subframes they seem much beefier. Do you think this may be a weak spot after
some heavy use of the hoe. I've attached a picture of the saddle on one of Kubota's subframes.

Thx for the support, LURE.

Why do you say the Kubota's saddle is beefier? It's only 3/4" or 1" thick and it's pin is supported
on only one side of the plate it is attached to. My saddle is 2" wide and forces bear on the pin
thru the center of the 1/2" plate. What is your pin diameter?

I know the pins on my B21 4-pt hitch were thicker at 1.5", but they were supported
on both ends in U-shaped weldment, not unlike your upper support. The mainframe was
1" thick where the saddle was, too.

The vertical forces on this subframe are divided among the 4 main connections,
since the toplink pivots. Most of the time the hoe is used, the larger forces on the
saddle and it's pin will be horizontal: rearward when digging, and forward while
lifting. These forces will be compensated (and opposed) by those on the toplink.
I think it will be plenty strong enough. I seems stiffer in use vs. the one on my Kioti.

 

[dfkrug]

Here's a short video of the tractor and hoe in action:

https://www.youtube.com/watch?v=1OT1sI95414

It is now up for sale.

 

[dfkrug]

Very nice work. Could you explain how the
backhoe is attached to the tractor? One of your pictures shows 3 bolts. What
else holds it on? Never had a backhoe.

Sorry I was not clearer.

The back surface of the hoe in photo #1 bolts to the surfaces you see in the
2nd photo. 3 bolts on each side. You can see the holes.

 

[Luremaker]

Thx for the support, LURE.

Why do you say the Kubota's saddle is beefier? It's only 3/4" or 1" thick and it's pin is supported
on only one side of the plate it is attached to. My saddle is 2" wide and forces bear on the pin
thru the center of the 1/2" plate. What is your pin diameter?

I know the pins on my B21 4-pt hitch were thicker at 1.5", but they were supported
on both ends in U-shaped weldment, not unlike your upper support. The mainframe was
1" thick where the saddle was, too.

The vertical forces on this subframe are divided among the 4 main connections,
since the toplink pivots. Most of the time the hoe is used, the larger forces on the
saddle and it's pin will be horizontal: rearward when digging, and forward while
lifting. These forces will be compensated (and opposed) by those on the toplink.
I think it will be plenty strong enough. I seems stiffer in use vs. the one on my Kioti.

Oh that is not my subframe, BTW. I got that picture off another thread here on TBN when I was planning on building my own backhoe subframe. I now have a Woods subframe on my L3130 which I purchased from another TBN member and I'd have to measure the pin but I would say it's diameter is between 1 and 1-1/2 inches.

Great video! Your subframe is strong and stiff with out any movement at all when you are lifting and placing that rock.

Here is a picture of my woods subframe taken while I was installing it. Notice how long they made the part which stays attached to the backhoe. I think they did that so the 3pth can remain attached to the tractor or for tractors with cabs.