Forging a tree root cutter

[Abby Babby]

I need to forge a root cutting tine for my backhoe.  In researching tool steel I was a little overwhelmed,  ok, a lot overwhelmed.  What I found was V3 steel. Is there a better choice. I am not sure what will be the chief attribute needed for an implement like this. I have to remove hardwoods and pine trees roots. Thank you in advance.

Regards

[Dave51B]

Abby, I probably won't be able to help with the steel type, but I am a retired hoe operator. What size hoe do you have? Are you thinking of a single ripper tooth? Just a bit more info should help.          Dave

[Alan Evans]

I made an old woman's tooth for my little 360 bobcat from 50mm (2") square mild steel and just tipped it with 312 rod. It was not for roots but breaking up the limestone layers in the bottom of the trench.

Your actual hook and carriage just need to be strong enough to take the pull, so can be made from mild steel rather than needing anything stronger or more exotic, the back hoe won't mind if is from a heavier gauge softer metal or from a lighter and stronger alloy.

The cutting edge is your only need to have something hard and keep a sharp edge. I would be inclined to modify a bolt-on bucket tooth. Which will hold an edge and can be replaced easily if it ever did fail. 

A welded on lump of Hardox bucket edging could also be used for cutting edge.

Alan

[Abby Babby]

Gentleman,  thank you for your responses.  I have a Kobota L35 with the factory backhoe.  I appreciate the guidance on a much cheaper and probably superior method and material.  Also I apologies for the late response,  I am figuring out how to use this site.

Regards.

[Glenn]

Best way to use the site is daily (grin).

[Alan Evans]

I have just dug this out from the long term storage nettle patch as I happened to be passing by with a strimmer.

The main piece is forged from 50mm (2") square mild steel welded to 12mm (1/2") plate. You can see the 312 on the tip has survived unscathed.

The little Bobcat X320 is a 1.5 tonne machine with a 3,408lbs bucket crowd and it could not bend the 50mm. As far as I can see your Kubota model has the same size motor but double the kW and has 50% more digging power...but I would still have every confidence in the 50mm square.

 You could always make a sharks fin shaped blade...In fact I might just put in a hard edged gusset plate in mine for tree roots...and it could double as a mobile log splitter. I already attach my log splitter ram to the dipper auxiliary pipes for firewooding.

After use as a trench bottom ripper tooth I added the cross bar and some 20mm (3/4") square mild steel fork tines so I could weed an overgrown chippings heap. At one stage I added some bits of 6mm(1/4") stainless flats to link all the tips together for stone sorting and digging out clay for a pond. Cut them off to revert to weeding again.

Every now and then the 20mm tines get snagged and bend but I just use the hydraulics to bend them back.

The time consuming part is making the pin plates. Once that is done you can weld any configuration of implement to it and keep modifying it to suit the project...

Alan

[Abby Babby]

Thank you for that picture. That is exactly what I was looking for.

[Charles R. Stevens]

I was envisioning a “V” shaped cutter like a garden weeder. Cheap would be  grader blade for the cutting edge and A36 for the rest. Abrasion resistance is the thing here. One simply sharpens the edge to a sixty degree edge with a grinder and goes to town. 

Another option would be a thumb and claw arrangement to acualy shear the roots.

Stumps are a pain unless you have a grande machine. Old school used a special cat claw shaped plow that Pivotson the stump to cut the roots, then the beam was chained to the stump to provide leverage to pull the stump over to expose the tap root.