Used auger bit question

[Tim Null]

I just picked up a set of Jennings auger bits from e-bay. When I went to try them out is some maple scraps, they did not work. The lead screw would go into the wood and the bit would start to bore, but then it would stop. The lead screw would just spin an the bit no longer cut. Only a small hole, about 1/8" or so was actually cut. The bit would pull out, the screw was full of wood in the4 threads.

What is the problem? The cutters seem sharp, but maybe not enough? This occurred on all of the bits I tried.

The largest two had no screw, just a sharp point like on a forstner bit. The third had a screww, but the threads were basically stripped. The smaller bits had good threads, but still the same results.

I am a bit disappointed so far. 9 bits for 39.00 plus shipping. Anyone use the new bits from Traditional Woodworker or Tools for Working Wood?

[Jim Koepke]

It sounds like they may have been improperly sharpened.

Here is something I wrote on this before:

http://www.sawmillcreek.org/showthread.php?131238-A-Bit-About-Augers...

If the underside of the cutting lip has been filed, it may not be hitting the wood at an angle to cut. This would explain the lead screw stripping out.

If the spurs were sharpened on the outside, then the bit can jam in the hole to prevent it from proceeding.

The spurs on an auger need to extend from the cutting lip to a little past the peek of the next thread of the lead screw. If it doesn't, then you will get a little tear out where the lip starts to cut where the spur didn't score the wood.

Some close up pictures might help. Otherwise, the auction number if it has been less than 30 days and the pictures are hosted by ebay.

Don't put the ebay link as that is not allowed on SMC.

jtk

[Pam Niedermayer]

Did you try to drill into the end grain?

Pam

[Mike Holbrook]

Is there some advantage to these older bits I see on ebay, especially the augers?

I am in the market for bits for my old hand drills and braces and see these old bits going for what seems like generous sums. I believe Lee Valley, among others, offers new bits that will work with these braces. I would think the newer bits might have some design improvements but the market for the older models seems strong too.

[Bill Houghton]

+1 on the sharpening. If they're not sharp, you'll get this even in pine.

Another point: The lead screws on auger bits come in various pitches. Finer threads work better on harder woods. Even sharp, it's possible for a coarse-thread lead screw to strip out in hard wood - the lead screw is trying to pull the auger through the wood faster than it can handle.

[Tim Null]

Pam, no I did not try end grain. Would that make a difference?

Lee Valley only carries a bit that is to be used on softwoods and green hardwoods. Traditional Woodworker carries bits for hardwood use, one made in
Brazil, one in England.
Anyone use either of these?

[Tim Null]

So on the bits that only have a sharpened point or a stripped thread, they are useless I guess.

[Peter Pedisich]

Tim,

I own one of the new Irwins (Brazil) and I purchased a set of older (1950's-60's?) from Brass City Records that were made in USA. The pattern is identical, except the older ones are better finished. I went with the Irwin solid center style as almost all I do is in softwood. The Jennings type are more expensive for both new and vintage...must be better.

I wonder if someone could fix the threads on yours?

Good Luck,

Pete

[Mike Holbrook]

Although Traditional Woodworker carries bits that they suggest and design for use with braces; I do not find reference to using those bits with hard wood. Lee Valley does offer single flute augers but cautions about using them in dry hard wood. Under their Hand Drill> Braces area Lee Valley offers adapters for using 1/4" hex, 3/8" sockets, tenon cutters.... with braces. Garret Wade offers some similar bits to Lee Valley's (green wood bits) but does not caution against their use in hard wood. The double fluted augers that the Traditional Woodworker offers may be better for drilling with braces in hard wood, would make sense; I just do not see it mentioned. Those double fluted augers are very expensive though.

With the exception of Lee Valleys specifics regarding using bits in hard wood, most vendors seem to avoid the subject. It also looks like much of the information assumes the purchaser will be using an electric drill. I am curious about real live experience using various bit types in hand crank drills and braces.

[Jim Koepke]

I am curious about real live experience using various bit types in hand crank drills and braces.

If the brace is a type that can hold a standard bit it should work fine. It is likely to be clumsy with short and smaller bits, but I used to drill a lot with a 1/4" bell hanger's bit.

jtk

[Pam Niedermayer]

Pam, no I did not try end grain. Would that make a difference? ...

It would behave much like you described, since the threaded screws don't work for going into end grain.

Pam

[Andrae Covington]

So on the bits that only have a sharpened point or a stripped thread, they are useless I guess.

Sadly, pretty much. The auger bit design relies on that threaded point to pull the bit into the wood. Without that, or even if it has the threads but they become clogged with shavings, the bit will just spin. This seems especially true with larger sizes which require more downward force to keep them moving through the wood.

Before you give up, try them in something soft like pine or aspen. I have found that I can drill larger holes in softer woods, just because of the difference in force required. Still, something like a 1/4" or 3/8" should be easy to bore through just about any wood short of ebony, ipé, etc.

I am always reluctant to complain to the seller if things weren't quite as I hoped; I have let some minor to middling issues slide, especially if I felt like I didn't pay much. But if you can't get any of the bits to work... depending on how they described the condition, you probably have a valid case for sending them back and getting a refund. The auction resolution policies these days heavily favor the buyer, so you can get your money back whether you have a legitimate cause or not, IMO.

[Johnny Kleso]

Does the bit feel and look sharp?
I am sure they can use a sharpening but I can't believe they are all stone dull..
You are pushing hard on the pad while cranking, correct?

The bit does not pull it self in, you must push hard as well as crank..

[lowell holmes]

If I were going to purchase new bits, I would order one bit and test it before ordering a set. I've purchased tools from both companies and never disappointed in either company. I bet they will communicate with you about your concerns.

I have a set of 1960's ventage Irwins that were my dad's. They do quite well except for a 1" bit that just wouldn't pull into the wood. A friend had a new one and gave to me. It is a 1970's vintage Irwin and does very well.

[Jim Koepke]

I have a set of 1960's ventage Irwins that were my dad's. They do quite well except for a 1" bit that just wouldn't pull into the wood. A friend had a new one and gave to me. It is a 1970's vintage Irwin and does very well.

These bits were made to work. If a bit doesn't work, it is often possible to determine why and correct the problem.

An understanding of how a standard auger bit works will help. The screw starts the initial hole and is the guide for centering and pulling the bit into the work.

For larger bits it is often a good idea to drill a pilot hole a little less than half the diameter of the guide screw's widest point to prevent splitting of the wood.

As the lead screw penetrates the stock, the spurs will come into contact with the stock and if long enough will scribe a circle of the outside diameter of the hole being bored.

When a complete circle is scribed, the cutting lips should start taking shavings from the surface of the stock being bored.

Now for the problems that can happen.

The lead screw might not be cutting cleanly. If the threads are buggered, then you may be out of luck. You may be able to touch them up with a needle file. The bit may be useable for rough work with some effort if the lead screw is not restorable.

If the spurs are too short, then there will likely be a rough edge where the lip splits the wood when it starts cutting. What happens is the lip starts to lift the wood before the edge is scored by the spur. If the wood is not scored first, the lifted piece can tear out beyond the edge of the "defined" circle.

If the spurs have been filed or abraded on the outside, then they will scribe a circle that is smaller than the outside diameter of auger bit. It is just against the nature of physics to allow a 5/16" shaft to fit into a 19/64" hole.

Then there are the cutting lips of the auger. These are like little chisels lifting the wood out of the circle that the spurs make at the outside and the lead screw makes at the center. The peak of the thread on the lead screw should actually transition into the edge of the cutting lip. If the lip has been sharpened on the underside, then the edge will never be able to touch the wood in order to cut it and lift it out as a shaving. With a properly sharpened auger bit, both lips will cut equally. If one lip is doing most of the work it can cause a bit to have a tendency to wobble and bore a hole that is not straight.

If the lips have been messed up by improper filing, you can park your car on top of your brace and turn for all your worth, it is not likely to bore through any but the softest of woods. It won't really be boring, it will be more like pushing a flat rod through the stock.

It may be easier to figure out what problems a bit may have than it is to correct the problem.

jtk