Hardfacing welding rod. Back in welding class years ago I ran some on a rock crusher. Later while doing farm work we put it on ripper tips and stuff like that.

http://www.mylincolnelectric.com/Cat...owse=104|1847|

It can be difficult to run, and you will reapply from time to time, but if you are only running the occasional hole that would be the ticket.

Wearshield ME might be the stuff for your application.

 

I'd suggest to a local welding shop and inquire about tungsten carbide edge for core drill.

They can (or you can) apply it on the end of a piece of pipe to build you own core drill any dia. and length you need. The opposite end can be fabricated to attach to your gear box on you 3-pt attachment post hole auger.

Seems to me like they braze it on.

Scroll down a little on the site and you'll see what it looks like. It's a very rough, aggressive cutting material. Rock does not phase it.

http://www.dimatec.com/products/core...n/tungsten.htm

 

Ok I ordered a box of these rods.
My thought is to take the replaceable blades for this auger and weld a few beads along the edge. Grind those edges down to be somewhat sharp and then maybe cut notches into those blades.
Good idea??? Other options??

 

Once you've run that stuff I wouldn't plan on cutting. Grinding wise, use a fine grit, keep it cool (have a hose or whatever) and go slow and you should be able to put somewhat of an edge on it.

Let us know how it works out.

 

Will do!!
Hopefully we'll be cutting through some rock soon.

 

Well, if it doesn't last, at least you've tried the cheap, easy solution first...

 

This is your answer. At least a good place to start. You can get tungsten carbide with a smooth surface, or with a grit.
The problem with trying to harden a whole drill bit is that it very easily may become brittle, and break.
The reason being is that you would most likely be guessing at the carbon content of the steel in the bit. The carbon content would determine the exact temperature the bit would be heated to, and whether it would be tempered(hardened) by water, oil, or air.
Metallurgy is more complicated than you think. That's why those bits are expensive.
Depending on the "hardness" of the drill bit, along with the extra "hardness" of the tungsten, against the "hardness" of what you are drilling will determine whether the bit will bend(soft), or break(brittle,hard).
All these variables are factored in with the shear pins, which are designed to break first and save your drill.
Good luck. You are about to find out why drilling equipment is expensive, and professional drilling outfits charge what they do.

 

You are on the right track except that you will not cut the rock, you will actually shatter it, depending of course on the rock. I would not spend a lot of time attempting to get a toothed edge, they will catch and you will snap or bend your auger, or it will just stop all together. If it were me, and it was, I would hard surface you auger blade as it is. The hard surface essentially becomes a wear portion for your auger that you will have to replace, or re apply. One thing to note is that different formations drill different with different speeds and and different drilling pressure. Once you have varied your speed and drilling pressure, and have had limited luck, you may try drilling with water. You may also try drilling with heavy salt water, or even acidic or basic water (and acidic and basic salt water). The different chemistries will aid in breaking down the surface of the rock to soften and create fissures which will aide in fracture.

You wont need to have drastic acidity or alkalinity just a couple of points above and below 7 (neutral). pool chemicals will work fine.

Assuming you are drilling in the same areas, keep notes, you should be able to use the same drilling parameters for most everywhere on your location.

If you do use chemically treated water to drill, be sure to wash off your auger immediately, the heat and pressure from the drilling will 'open up' the steel causing it to rust a bit faster. wash it with clear water and then spray a light coat of diesel or used motor oil to seal it off.

HTH

 

It's pretty mch all the same stuff. The upper layer is a softer yellow limestone and clay. They overlap each other for a few feet. At 16' (not going near that deep) it turns into a much harder (gray limestone).

 

With limestone use an acidic solution. If you auger just spins, drill a 1/2" hole (hammer drill) in the center of the rock and pour vinegar down it. it will react instantly. If the vinegar isn't strong enough, get some muriatic (hydrochloric) acid and pour it into the hole you drilled. The limestone will almost disappear. Same process we use to get a well going. Shoot a hole into a limestone formation then fill it with acid to soften up the fissures and make the limestone more porous. Its fun to watch too!!!!

With the limestone softened and fractured it will churn out like butter. And you wont wear out any equipment beating on it.

Don't forget PPE. Glasses and gloves are an absolute minimum.

 

You can probably dilute the muriatic acid in order to stretch a bottle.......X2 on the eye protection and acid proof gloves.

 

Funny.....I was cleaning out my shop yesterday and found a qt of HCL on a shelf.
Glasses????? We don't need no stinking glasses!!!
J/K, I always wear eye and skin protection.

 

Good.......one of my guys ended up in the hospital over night because he refused to wear glasses. This was with muraitic acid diluted to 9:1 for cleaning grout.

 

You should see me when I'm mowing my yard.
Rag on my head, safety glasses, earplugs and long sleeves!!