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In a recent thread about cutting purfling/binding ledges there were a number of comments about making sure the cutter is clean and honed. How do you hone the cutter?

Thanks,
Max

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Max Bishop
Brighton, Michigan

I use a diamond "stone", and hone the inside of the cutter only. Not every time I use it, but hopefully before it gets dull enough to tear out (on soft woods, especially).

Just as important as honing, is to remove any resin buildiup on the cutter, as this will also inhibit a clean cut.

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Rian Gitar og Mandolin

Thanks, Arndt. Can you direct me to any detail directions or tutorials?

Thanks,
Max

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Max Bishop
Brighton, Michigan

Here you go: http://www.highlandwoodworking.com/care ... rbits.aspx

I do it just like Highland explains it. Soak in blade and bit cleaner to remove resin, then use a diamond paddle to sharpen the flat face. That's all there is to it. Just give each flute the same amount of strokes on the paddle. I start with 600 then move up to 1200. Doesn't take long.

I forgot to mention that I use a spiral up-cut bit to cut my purfling/binding ledges. The tutorials 've seen on Youtube are for flat-sided cutters.

Max

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Max Bishop
Brighton, Michigan

I don't know how to sharpen spiral bits, but for my straight bit (I use the Stewmac binding cutter set) I use a fine stone, and rub the bit against it. I lay the stone flat on the table, and hold the bit, while guiding things with my fingers, its not a difficult at all.

To remove resin from the cutter I use some alcohol on a paper towel to dissolve and wipe it off.

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Rian Gitar og Mandolin

Spiral bits may not be re sharpenable. I toss them when they get to that point.

Has anyone sent their Stew Mac bit out to be re sharpened. I have a good sharpening guy here that I trust but I suspect professional re sharpening will alter the original diameter. A bit of a pain to figure out which bearings cut what.

This is such a simple task that I don't see the need to send it off to be sharpened. It can be done at your bench with your choice of sharpening stone in about a minute.

I do similar, with diamond cards raised off the bench on an MDF block.
I've gone as small as a 3mm bit.
Wearing gloves (thin, soft leather) can prevent nasty cuts to the guiding fingertips...................

Spiral cutters would be a whole different ballgame.

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The name catgut is confusing. There are two explanations for the mix up.

Catgut is an abbreviation of the word cattle gut. Gut strings are made from sheep or goat intestines, in the past even from horse, mule or donkey intestines.

Otherwise it could be from the word kitgut or kitstring. Kit meant fiddle, not kitten.

Fine! I was just wanting to help the local economy. Diamond card it is.

I accept donations.

Don't toss your straight bits! Their smooth shafts make great scraper burnishers. Drill a hole into the end of a big dowel/other handle and bury the cutter end of the bit into it.

"Spiral bits may not be re sharpenable. I toss them when they get to that point"

Spiral bits can be resharpened professionally, and considering the initial cost, this is probably worth doing.
Shear angle bits offer some of the advantages of spiral bits (shearing cut), cost less, and can be resharpened like straights (with a diamond hone)