fabricating a new and improved bucket for my mini-excavator

[dfkrug]

I recently imported a new mini-X from China, and it has been very useful. The buckets that came with it, however, leave a lot to be desired. They are too flimsy, too shallow, and use soft cast steel teeth.

This will be the 2nd bucket I have made from scratch, since I made one for my tow-behind mini-X, the CADDigger 728. Fabricating that bucket, back in the mid-90s, showed me how NOT to do it next time. BTW, the CADDigger designer (CADPLANS) is a TBN member. That bucket was 12" wide, and the carcass was 1/4" steel plate. Bending it into the curved shape necessary was tough, requiring lots of force and O/A torch heat.

First, let's look at the OEM 14" wide bucket and how it is made.

 

[dfkrug]

So here is my plan:

My mini also came with an 18" bucket, which I modified and used primarily. I also used the ripper tooth that I bought at the same time. I have about 120 hours total using these two implements to dig trails and remove small stumps and large rocks.

I showed the modified bucket in my Chinese Mini-X thread:

Importing and modifying a new mini excavator from China

It has been a while since I posted a Big Project on TBN, so here we go again. I have been on a quest for a mini-X, so I imported a new one from China. It has been complicated and took a lot of time and energy, but it is here and working. Over the next week or so, I will post about my search...

www.tractorbynet.com

Primarily, I welded on homemade sharper teeth. Worked great. The ripper tooth also works great, unmodified.

The 18" bucket is too wide for many applications (e.g. trenching), and it is too shallow and easy to bend. So I plan to make a deeper, narrower bucket with more reinforcement, plus homemade teeth.

 

[ArlyA]

Those 1/8 side plates are sure light!

 

[timbatrader]

strength verses weight very temping to over build something like this but every extra kilogram of weight you build into the bucket is a kilogram less dirt in each bucket full over the life of the bucket that thousands of tons of dirt. so my advise make it light use better steel and don't design it to last forever that's false economy

 

[ArlyA]

strength verses weight very temping to over build something like this but every extra kilogram of weight you build into the bucket is a kilogram less dirt in each bucket full over the life of the bucket that thousands of tons of dirt. so my advise make it light use better steel and don't design it to last forever that's false economy

What steel do you advice other than mild cold rolled? This is all I've ever used here in the states for 1/8 plate.

 

[dfkrug]

Dissecting the OEM bucket....

I reused the pin bracket and support tube, plus the cutting edge is 5/8" thick, so I reused that, too. The curved section of the carcass is 1/8" steel plate, which is far easier to bend, vs. the 1/4" plate I used last time. 1/8" steel plate wear strips will be welded onto 1/8" plate, as the OEM did. That gives you good strength, but far easier fabrication.

I will also increase the side carcass thickness to 1/4" steel, with a reinforced edge that makes it a total of 1/2" thick there. My total width will be 12", which is a good compromise for trenching and digging, but less likely to get clogged with sticky soil. My tractor's backhoe has 100s of hours on it with only a 12" bucket.

When cutting apart the OEM bucket, I noticed that the support tube was quite substantial, similar to 2" OD, 5/16" wall DOM tubing. I placed some 2" OD 1/4" wall DOM next to it in photo for comparison. Nice.

 

[dfkrug]

So I made a template out of 1/8" plywood, and used it to cut 2 side plates out of A36 steel 1/4" plate.

When making something like this, I like to reuse what I have, but also I buy and cut up tougher steels for wear edges and teeth. So-called plow steel. I also learn from failures to make other implements strong enough or wear-resistant enough for the duty I subject them to.

 

[M59]

So here is my plan:

The 18" bucket is too wide for many applications (e.g. trenching), and it is too shallow and easy to bend. So I plan to make a deeper, narrower bucket with more reinforcement, plus homemade teeth.

View attachment 756752

dfkrug,

I am shocked you could actually dig with such a lightweight bucket without either tearing the pin bosses off or wracking/ collapsing/ tearing the bucket to shreds.

I, before I moved to dedicated quick attach hitch for the M59, had a clamp on to the FEL hitch for moving trailers around the property. The clamp on hitch had a top plate of 1 inch by 4 wide steel through which the clamp was threaded. I made the mistake of setting the bucket down hard, under power, and bent that 1 inch top plate up 20-30 degrees.

What is the Chinese mini x model and weight? ( Just saw you have a model XN08/ 1700 Lb machine so I am guessing you could run 1/4" back and sides with 3/8 side cutters and some nice replaceable Esco or Pengo teeth)

I run backhoe buckets on the M59TLB ( 11K Lb ) with following specs
3/8" AR400 Sides
1/2" AR400 Side Cutters
3/4" Hardened Cutting Edge
3/8" 572-50 Shell
Esco teeth

 

[timbatrader]

What steel do you advice other than mild cold rolled? This is all I've ever used here in the states for 1/8 plate.

over here the brand name is Hardox my guess is that something similar is available over were you are but with the USA trade restrictions on steel maybe it is priced out of the market The most popular abrasion-resistant steel with excellent structural properties.

 

[dfkrug]

Next, I clamped and welded some 12" A36 1/8" steel plate to the pin bracket and cross-tube. The side plates were then aligned and welded to the cross-tubes.

Bending the plate around and tack-welding was the next step, which used a cable come-along. I welded the plate inside the side plates (rather than on top), for a longer-lasting welded junction. Large C-clamps were also used.

Lastly, I reused the cutting edge, added wear plates, side reinforcement, and a lifting hook.

I also wanted a 12" bucket with one central ripping tooth, rather than three. This allows me to use the bucket as a ripper AND a bucket. Works very well. The tiny teeth in the two corners were more for reinforcing the corners (the first place I usually see cracks).