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Is there a good way to sharpen a router bit? Any guidance is appreciated...
Steve

I think it's better to give it to experts... But, you might want to know that the bit will loose of its precision (maybe a 1/2 bit will become a 15/32, by example), whatever the way you sharp them. So, for the price that cost a bit, maybe it's better to buy a new clean, sharpie and precise one.

Francis

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Francis Richer, Montréal
Les Guitares F&M Guitars

A router bit will always become a bit distorted as a result of being sharpened regardless of who does it by virtue of the fact that the edge is angled. You always sharpen the flat side of the bit (never the angled side). This will remove a tiny amount of carbide and the new edge will be slightly down the angled edge from where it was originally. This is usually no issue at all. On a flush trim bit, however, the bit will come slightly out of alignment with the bearing and no longer trim exactly flush. You can take care of this by wrapping a piece of tape around the bearing to make up the difference.

Use a diamond stone and just rub the flat side of the bit on it. It works great in a pinch, but after a few times of this it is better to send it in to someone who has a good sharpening system. The small bits are probably cheaper to buy new. Hope this helps.

I don't bother , most router bits are very economical. Carbide takes special tooling to sharpen and I was never happy with the end result . Buy new ones.

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John Hall
blues creek guitars
Authorized CF Martin Repair
Co President of ASIA
You Don't know what you don't know until you know it

I'm not sure about this (above). When you sharpen a router bit, the sharpening happens on the cutting face (the flat face). Because the back side of the cutting edge has a relief ground on it (a few degrees of angle), the diameter of the flush trim cutting bit is slightly reduced (a few thousandth's on each sharpening). Wrapping tape around the bearing will only increase the amount of clearance between the bearing and the cutting face, and will leave even more waste to remove with a file, scraper or sandpaper.

cheers

John

Throw it in the trash and but a new one.
James

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James W Bolan
Nashville Tennessee

John, you are right about this. Viva la dislexia!!

I have a small Fallkniven DC3 combination Diamond/Sapphire stone which you can touch up an edge with to give it a little more life, though its a compromise not as good as a new/resharpened but will extend the life

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Formerly JJH

I learn more from my mistakes than my successes

If you are going to do it at all, take it to a pro. I've had fair luck with the person who does this though our local WoodCrafter store.

For bits that really need to be sharp, like routing channels for binding, etc., take John's advice and toss them.

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Jim Howell
Charlotte, NC

So, you guys are suggesting to toss the LMI down sheer bit they sell for cutting binding channels instead of sharpening it?

Maybe that's the way to go... How many binding jobs should one get out of a bit???

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Fine diamond honing stick. Same number of passes on each blade. 3-4 swipes should do it.

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Howard Klepper
http://www.klepperguitars.com

When all else fails, clean the shop.

I'm with Howard for Rod's reason.
For a couple of years now I've been using a diamond sharpener to touch up the flat faces of router bits.
Helps to clean off any resin/oil build up on the face first.

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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.

I think it probably is important to clean off the trash...

The thing I worry about (Though it may not be an actual problem) is balance...

Things spinning up at 24,000 rpm vibrate like crazy if they aren't balanced right...

I think on a binding bit, I would probably buy a new one.... though I think the duty cycle on a Carbide bit should be quite a bit longer than 1 or 2 guitars...

Thanks

John

I had bad luck with my local machine shop, so mileage may vary. I now send my SM binding bits to Highland Woodworking sharpening service and they're as good as new, and it's inexpensive.
For most bits I just buy new as well, but binding and pattern bits are expensive.

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Laurent Brondel
West Paris, Maine - USA
http://www.laurentbrondel.com/

Check out these diamond mini-hones, they're not expensive and would have other uses around the shop if you don't like them for router bit sharpening.

http://www.woodcraft.com/Family/2005910 ... -Hone.aspx

René

Dyslexics of the world Untie!!!

Darrin

Join ADN!

National Dyslexics Association

Laurent,

I have the LMI kit. Do you think Highland can do this bit? And what would you estimate the cost to be including shipping?

Thanks,

Mike

If you are using a bit with a bearing on it, wouldn't it change the clearance, slightly? Might not be enough to worry about, if you leave your bindings proud.

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Waddy

Photobucket Build Album Library

Sound Clips of most of my guitars

I think the LMI rabbeting bit is more standard than the SM one, and you may be able to find an inexpensive replacement. I'd start looking at the Grizzly rabbeting set #1, with which the SM bearing are compatible BTW.
Highland Woodworking subcontracts a shop in NJ to do this:
http://www.highlandwoodworking.com/saw-sharpening-service.aspx
It's less than $5 for a bit, they'll sharpen most bits and blades, and they're good.
Waddy, they take very little carbide off the flat edge (less than .0005"?), it is not noticeable. Theoretically, after a few sharpenings the bearings will have different values.

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Laurent Brondel
West Paris, Maine - USA
http://www.laurentbrondel.com/