How do you "Harden" Metal

[Nowland Farms]

I have just purchased new teeth for my auger and wnay to make sure the metal has been harden since the Guy at feed store didn't know.

How do you harden metal to make them last longer?

Seems like I remember someone saying you heat to cherry red and dip in oil but don't remember the details.

Any ideas

 

[denoginnizer]

Sounds like a good way to start a fire.

 

[Bez!]

I have just purchased new teeth for my auger and wnay to make sure the metal has been harden since the Guy at feed store didn't know.

How do you harden metal to make them last longer?

Seems like I remember someone saying you heat to cherry red and dip in oil but don't remember the details.

Any ideas

Teeth? For an auger? What you using this thing for?

Why not just purchase a harder metal?

I know metal can be hardened - waiting with bated breathe for the answer myself.

Bez!

 

[dun]

Heating and quinching in oil or water will harden metal. Done wrong and it's a screwed up mess. An eisier way is to just get some hardface rod and weld it on the surfaces.

dun

 

[Saltydawg]

http://www.technologystudent.com/equip1/heat1


This procedure will work good for your cutting teeth. Most important part is the second heating and watching for the blue in the metal then slowly cooling from that point.

 

[Nowland Farms]

Salty,

Thank you for your response. I will try this on the new teeth for the auger. It seems that the tooth on the outside normally wears out the fastest. I have several holes to "drill" in an old abanadon gravel roadbed that is pack HARD.

Thanks again.

 

[Dusty Britches]

Nowland Farms - if it is just a few post holes, why not rent a rock saw? That's just a retorical question, since you already have the teeth for the auger bit.


Sometimes I wish I had a rock saw, as tough as clay gets during a drought.

 

[edb130]

Dun is right. I work for a Welding & Cutting Manufacturer and I can tell you that simply hardening your metal is not going to make the teeth last considerably longer. Hardened metal can actually become brittle from the heat treatment and break faster. Welding with a hardfacing material (i.e. rod, wire) containing materials that will withstand both impact and abrasion would be your best choice to improve the life and performance of your auger teeth

 

[Susie David]

Flip the switch on the trusty o'l Lincoln and run a bead on the under side of the teeth, chip the slag and do it again. When the weld bead starts to wear repeat the process. Instant heat treating and the addition of hardened material.
Alot of different ways to heat treat depending on the type of steel and the degree of hardness that is desired. Heating and allowing to cool is anealing (softening) white hot heating and quenching in brine will harden the entire piece of metal and will be subject to cracking because it has lost it's natural flex. Now if you want to draw a temper in the piece, heat beyond white hot until it looses it's magnetisim and use a heavy steel tool (hammer) to draw the temper away from the desired edge. Works well on knives, chisels and the like.
And that's my two bits worth.
Dave Mc

 

[Bez!]

Crikey!

You auger grain.

You use a post hole digger for drilling in the ground! Or better yet - use a backhoe - faster and easier. Even in good ground.

Seems I need to learn that "southern speak".

I was darned if I could figure out why someone would want to put teeth on a GRAIN auger!

:lol:

Bez!

 

[msscamp]

I am totally confused here, the post hole augers I've seen have no place for 'teeth'. Help?

 

[dj]

msscamps
http://www.daken.com.au/prod_tr_phd.htm
scroll about half ways down to the pic in "Heavy Duty Augers"
you can see the "teeth" welded on this one. Other brands might be bolted or pinned on

 

[cfpinz]

I am totally confused here, the post hole augers I've seen have no place for 'teeth'. Help?

The augers have replaceable bolt-on edges, or "teeth", at the leading edge of the spiral flights. They also have a replaceable point in the middle of the auger, too. Go to Danuser's websight, they may have some pictures showing different types of teeth.

cfpinz

 

[msscamp]

Thanks guys! I see now. I knew about the point in the middle at the bottom of the auger, but I have never seen the teeth on the spiral. Interesting!

 

[sidney411]

We just put carbide teeth on both of our augers, $150 a pop, but well worth it when drilling in rocky areas.

 

[Saltydawg]

Yes Tungsten Carbide is what's normally used for rock teeth.

There's a very good reason profesional manufacturers don't use beads of weld to make hardened cutting teeth. It's impossible to properly temper the base metal and the cutting edge when they are joined this way.

Wear facing is used on things like snowplow and grader blades and bulldozer teeth because they don't actually have to "cut" anything and the ammount of wear is so great that they are just using it as a sacrificial coating to protect the base blade.

You will never find a high quality cutting tooth made using wearfacing.

 

[Bama]

The problem with harding a unknown metal is you don't know the carbon content. Differant metals use differant methods. Some air cooling some oil and others in a draw down furnace. Most good quality augers have pretty much the optium rockwell hardness metal on the teeth. To hard and they break, to soft and they wear quickly. Thats why the teeth are there, to prevent wearing of the flights. Most of them are replacable but most of us just weld them up when they wear.

 

[memanpa]

without knowing the type of steel to be hardened it is basically impossible to harden correctly! hi carbon? low carbon?
air hardening? oil hardening? water hardening? true tool steel?
all have varying degrees of hardening capabilities, and many steels require CONTROLLED temps and times to achieve optimun hardness and durability.
and of course there is always the chance of doing more harm than good if you are not sure of what you are doing
dave dun and edb130 have stated it as well as i can

 

[bgm]

without knowing the type of steel to be hardened it is basically impossible to harden correctly! hi carbon? low carbon?
air hardening? oil hardening? water hardening? true tool steel?
all have varying degrees of hardening capabilities, and many steels require CONTROLLED temps and times to achieve optimun hardness and durability.
and of course there is always the chance of doing more harm than good if you are not sure of what you are doing
dave dun and edb130 have stated it as well as i can

I'm a tool & die maker at my full time job, so I can say your right on the money with steel types and hardening.

Use of the wrong hardening procedures will damage the part. For instance if you quench a piece of air hardening steel in water, you will have cracks form and I have even seen the part turn to "gravel" in the bottom of the quench bucket.

After the steel is hard it must be tempered or drawn back to a useful state. If it's left full hard it will be brittle and crack VERY easily. Dropping some steels in full hard condition will cause them to shatter against the concrete floor.

As someone else pointed out, welding a hard face on unknown material can present possible problems as well. The heat affected zone at the weld can become embrittled and hard. Without the knowledge of the steel type it's difficult to know how to draw it back properly. You can end up with the built up hard face edge broken neatly off the piece right at the weld line.

Since it's in an auger application with replaceable teeth, failure of the tooth will not likely be catastrophic, so it doesn't hurt alot to experiment.

Just some info for what it's worth.

Good luck

Bryan

 

[putnamd]

most has been said - tool and die man knows and rightly said about harding varies - so to 'get' er done' use the hard surfacing rod on the teeth as they are replaceable. since you only have really minimum number to do. if it wears slap another coat of weld on - remember to grind to a cutting edge to help it dig in. I have been a shop teacher and farmer for 32 yrs- doesn't mean anything other then I have had some practice-so ya need to get it done by trying this. then go to buying the harden tiped if you want to spend the money- or use muscle- a 'pick' to get the ground started for the auger.
good luck