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greg Forster
03-24-2010, 7:14 PM
How do you sharpen a nose bit? Should just the lip on the bottom (similar to a center bit) be sharpened, or do the sides(flutes) also need to be sharpened?

When, thru use and many sharpenings, the lip is worn away, can this bit be modifyed to cut in a different manner?( several of the bits I have the lips are almost gone)

What is the advantage of a nose bit in use- why do they exist?

harry strasil
03-24-2010, 8:35 PM
picture would be nice, personally never heard of a "nose bit".

Jeff Burks
03-24-2010, 9:11 PM
A Nose Bit (http://books.google.com/books?id=jPIYAAAAYAAJ&dq=brace%20nose%20bit&pg=PA62#v=onepage&q=brace%20nose%20bit&f=false) is a type of shell bit for a brace. It looks like a carving gouge with a spur on the end pointing to the center of the sweep. They were mostly used for boring small pilot holes in end grain. As far as I know, when the cutting spur is worn off, it's time to retire the bit. I just don't see how you could grow the spur back without serious metal working skills. If, on the other hand, you had such skills it might be possible to grind back the existing end of a nose/centre bit and bend a new spur from the remains...but then it might be a lot less headache to just buy another one.

...and as usual Google Books (http://books.google.com/books?q=brace+nose+bit&lr=&sa=N&start=10) has lots to tell us of this subject.

Stephen Shepherd
03-24-2010, 9:22 PM
Greg,

Just sharpen the lip [nose] at the bottom and don't sharpen the sides or it will ream an oval hole. Sharpen it as you would a chisel or plane iron, flat on one side with a bevel on the other. Sharpen the bottom [outside] flat and the top [inside] with the bevel.

Once the nose is completely gone they can be made into gouge bits.

Stephen

Jeff Burks
03-24-2010, 9:30 PM
Oh I forgot to mention sharpening. I would agree that you sharpen the spur only, bottom flat on a bench stone, and the top of the spur with a fine tooth triangular file. The flutes are just there to guide the cutting spur as it spins around shearing the endgrain. The purpose of this bit design is to cut end grain without having the grain direction pull the bit off course, which happens with most common bits. And Stephen has a great idea about converting the worn out bit. A few minutes at the grinder and you could change a worn out nose bit into a shiny new spoon bit.

harry strasil
03-24-2010, 9:44 PM
I know it as another name. once I saw the picture.

Stephen Shepherd
03-25-2010, 10:02 AM
And Stephen has a great idea about converting the worn out bit. A few minutes at the grinder and you could change a worn out nose bit into a shiny new spoon bit.

Actually when you grind the nose off you are left with a gouge bit [sometimes called a quill bit] and technically not a spoon bit, which curves in on the end like a spoon.

Stephen

David Keller NC
03-25-2010, 1:32 PM
Actually when you grind the nose off you are left with a gouge bit [sometimes called a quill bit] and technically not a spoon bit, which curves in on the end like a spoon.

Stephen

Another word for these bits (the "gouge" bits) is a shell bit. They are mentioned often in early literature.