TEST DRILLING: Good for Safety, Bad for Blades

[Pomoxis]

I have one of those old "spoon type" Mora. I've had it for twenty years, but I have only been using it for three years. It started out sharp and stayed that way until recently. (I have done many 18" holes with it.) It didn't dull much over that time until this year. Why? Test drilling in shallow water! like I did last week.
For anyone with any auger: Be extra careful not to hit the bottom of the lake, no matter what you think is there. Of course it is very important to test drill when you are not sure how much ice. But, never let your blade hit anything other than ice, even for a second! If you learn that the hard way, it could ruin your trip, and every trip until you are sharp again. It took me about two minutes to do 4" of ice after it got dull. Luckily, it was just a scouting trip, 3 miles from home.
If you have a spiral auger with replaceable blades, it would be a great idea to carry an extra set in case you dull them by accident at the beginning of a trip, after you travelled so far to get there.
Sharpening straight blades, like those on a spiral drill, can be done. But you will need to do it right. It is very important to keep the same angles on the grind. The bottom of the blade may not be ground at all. The top of the blade is ground at a specific angle. Do not change that. I think I remember hearing that Strike Master will re-grind blades if you send them back. Am I right? That would be the right way to get them done. They have the grinder set-ups ready to go, and experience with exactly those blades.
My Mora spoon is sharp again and I got some bass & perch to prove it. Sharpening the spoon is more difficult than a straight blade, but it can be done when you understand grinding, cutter angles and metal. A spoon may not work as well as a modern spiral, but it is lighter and easier to carry on a 1 mile hike-in, through briers, brambles and snow, like I did yesterday. It can also double as a scoop.
I tried to get a blade guard for my spoon last year without any success. Finally, I found the original. Anyone else have any info or stories about spoon-type augers or sharpening problems?

Ahhh, I love adventure!
The only liquid I need is Beer.

[hali-man]

Sharpening the spoon is more difficult than a straight blade, but it can be done when you understand grinding, cutter angles and metal...

The only liquid I need is Beer.

LMAO
Hey Pomoxis-
I have curved blades and am having a real hard time getting the angle right. It's a 6" Nils.
Any advice?

[Pomoxis]

Is the 6" Nils a spiral auger or a spoon type?
I am not familiar with any curved blades used on spiral augers. Also, spoon augers are pretty rare nowadays.
"Convex" curved blades can usually be sharpened with typical grinding equip. by hand and with experience.
"Concave" curved blades can usually be sharpened with a Dremel type grinder with a cylinder shaped stone bit by hand and with experience.
If you are impatient or in a hurry, you can remove more metal more quickly with a sharp file rather than a stone. But you will not get as good an edge. You can start with a file and finish with a stone. If you have a "concave" edge you need to use a round or half round file and finish with a round or half round curved stone.
The most important thing is to maintain the same or nearly the same angles. If the "bottom" of the blade was not ground, do not grind it. You can see where the original grinds were. The same thing applies to lawnmower blades and scissors. A single ground blade is ground on only one surface. It is not like a knife, where it is ground on two sides.
When you grind an edge, it is quicker to grind at a slightly "steeper" angle, or at an angle that puts the stone in contact with the cutting edge rather than at the "back" of the grind. This will result in an edge that is more durable, but does not cut as efficiently. A "shallower" grind will result in an efficient edge, but it will not be as durable and will require much more grinding to achieve.
Don't worry about grinding at slightly steeper angles.  It is easy, and you will not have a problem until you go nuts.
When using power grinders, it is very important to not "burn" the blade. Do not let the stone grind in one spot for more than 1/2 a second. The stone should constantly move across the blade, never have a lot of pressure, and be cooled with water. If you see "blueing" of the metal blade, it is softened and damaged. It can be used, but it will dull quickly in the blue spots.
To sum up: It is best for most people to use the original manufacturer or a qualified sharpener to get good sharpening for ANYTHING. If you have some experience/knowledge about grinding/sharpening, and some good tools, you can get by very well.
I knew those long hours of studying cutting tool geometry and materials would pay off!

PERCH!

[hali-man]

Thanks- I'll try one more time...

[Sax_]

how bout taking a spud bar out next time lol

[Pomoxis]

My first time out in 1982, that is exactly what I used  8). And I got fish . However, the exact same rules apply for grinding a metal spud. It is a single side grind on steel. Sometimes I make suggestions that require a spectrum analyzer, a stereoscopic infrared spectrometer and a set of quasi-geometric particulate diamond cutters.
But knowing something about this stuff would help me survive, even if I had nothing but a piece of sandstone, a dead goose, and a shakenup old can of BUD. 

[TONYR]

I will strongly second everything POX said. The first thing I would recommend is that you buy a backup set of blades, or a second set when you buy a new auger. That way you never go unprepared into that cold hard world we all enjoy so much. I have 2 Mora spiral augers, a 5 and a 6 inch. The blades on the five are 4-5 years old and like new after a thousand holes. The six I expect will act the same.
     Here are a few things I will add to what POX said. Treat the blades of any auger with respect, careful with them at all times. This is not only because they can cut to the bone, but because they will last a long time if you don't abuse them. When putting the blade to the ice, put it down on the ice with a light touch, don't bang the blade into the ice. Keep the guard on when you are transporting. I general don't let the blades touch anything but ice and do it ever so softly when you do that.

[AJ Flag]

That's a good point to make, because nobody wants their auger messed up especially early in the season, but I know it depends on the water you are fishing but how far out should you go before you test the depth.  One so that you know it's deep enough, and two so that if in case it wasn't safe enough, you don't fall in too deep of water.

[Pomoxis]

When you are in familiar waters, you can walk away from shore into where you know it is 2 ft dp., then test drill. When you are not in familiar waters, there could be danger. Use the surrounding land to estimate what kind of dropoff there is. If it is a very gradual slope, you can venture farther out. If you are on the side of a cliff, well, you get the idea, I hope.

[AJ Flag]

Yea that's about what I figured, I was looking for the 2ft depth u gave me, that sounds good enough to make sure you don't hit your blade.