DIY Mini Digger

Colcreate · Jul 24, 2015

I have a few projects planned around the home where a mini digger would be useful but I'm on a really tight budget and need to spread the expenditure over time. Hiring a machine several times a year would be too expensive so after looking at some of these homebuilt backhoes I thought I would have a go at building my own.
OK that's what I told the wife, truth is I just really wanted to build a digger and I had a pair of old Land Rover axles in my workshop and some steel channels that were going for scrap.... 4wd backhoe?
So here is how I have started...
Strip and clean the axles which will be cut and narrowed.

No plans or drawings, not even a sketch just going to make it up with what falls to hand.

bcp · Jul 24, 2015

I've seen three types of homemade "mini-diggers."

1. Two legs and two wheels that change locations for towing or for digging.

2. Four wheels, engine and booms rotate like an excavator.

3. Old truck frame, with old, small tractor backhoe mounted on rear, front axle may be in place with a steering tongue, or replaced with a rigid tongue for towing. Pump may be powered by the truck engine, which remains in place for weight and pump driving.

If you had two front axles, that would allow a better turning radius, and the ability to move sideways at an angle.

Bruce

ptsg · Jul 24, 2015

Looking forward to see it running!

Here is mine I built from scrap:

I started building it with my dad with 10 years old and finished it with 18 years old. So don't worry about time as long as you get it running

Colcreate · Jul 25, 2015

I'm thinking along the lines of a tractor type vehicle. Simple but strong chassis, rigid rear axle with a pivot mounted front steering axle. Front end loader bucket with optional forks and a rear mounted backhoe.
I agree two front axles would be great for manoeuvrability or even an articulated chassis steer but I'm happy to keep this simple and run with what I have to hand. Here's the axles being narrowed.
I've cut 8 5/8" out of the long side of the rear axle to match the short side. I can use another short half shaft here. The front axle is offset differently so I've cut and welded the long halfshaft to keep the overall widths the same at about 4ft.

PTSG your digger looks awesome! So many questions... Do you have a build thread somewhere or link to more pictures?

ptsg · Jul 25, 2015

Ask whatever you need to ask!

I don't have a build thread but I can post whatever picture you need here, if you don't mind.

Colcreate · Jul 25, 2015

Chassis layout with narrowed Land Rover S2 axles, Suzuki transfer box and a Range Rover prop shaft.

The 6ft steel channels are 5" deep and fairly heavy so plenty strong enough for this job. The wheel/tyre on full lock has determined the width of the chassis rails.

bcp · Jul 25, 2015

Looks like this project won't be dragging on for months at this rate.

I've never seen heavy-duty clamps like those in your axle shortening photos. They look much more rigid than C-clamps.

If you tap your keyboard space bar after each photo attachment, they will be easier to see and select.

Bruce

Colcreate · Jul 25, 2015

bcp said:
I've never seen heavy-duty clamps like those in your axle shortening photos. They look much more rigid than C-clamps.
Bruce

They are Carver Rack clamps made in the UK specifically for welding and fabrication. The clamp thread is shielded to avoid spatter, best clamps around but expensive. I'm a time served sheet metal worker but have been off the tools for 20 odd years.

Colcreate · Jul 26, 2015

A few more pic's, rear axle tacked in place and rear cross member welded

Need to figure out the front crossmember and axle pivot. The chassis rails at the front are spaced with a temporary brace.

Colcreate · Jul 27, 2015

Front axle pivot, the diff housing is still slightly off-set so I've shaped the end of a piece of 4" x 1/4" box section to fit the contour of the casing. I have some 2" round bar that I can turn bushes from for all the pivot points and some EN8 bar for pins. Might need some radius arms but will see how it looks when it's rolling.