Best router bit sharpening file

[Don Morris]

I've been doing a lot of routing lately and noticed that some of my router bits need resharpening, or replacing. Given the cost of my latest large cove bit, I would prefer to resharpen it, rather than replace. Some of the bits have shapes that easily lend themselves to file sharpening. I saw an add recently for a diamond faced file sharpener. Wondered if there were people out there with experience in this area, before I go ahead and pull the trigger. Brands? Shapes? Other recommendations?

[Rick Potter]

I use those diamond files on a plastic stick. Look like tongue depressors. You only want to lap the flat face of the carbide. Do not mess with edge of the curved area. I do it in the kitchen under a slowly running faucet. Helps keep the file clean. Take off any bearing first.

Rick Potter

[ian maybury]

I looked at this, but concluded the finish on a new router bit seemed very fine compared to the grit of any slips i had. Can you say Rick or anybody else what grit and type of slip might be advisable for this sort of job?

ian

[Curt Harms]

You might check into people in your area that can sharpen carbide. I had a couple bits touched up just to see how they came out. $4 each and the bits seem fine. One was a rabbeting bit and another was a straight bit. I don't have any bits with curves that need attention right now.

[ian maybury]

Thanks guys, that's opened up a new perspective for me. Pardon if what i've linked below is old hat Don and Rick. I have to admit to buying bits as needed (which hasn't been all that often) and chucking them to date....

I took a little dig on the web and the following came up:

There's a nice little video on quality and care of router bits here, it includes honing them using blue and then red DMT diamond slips: http://www.youtube.com/watch?v=NBcAT0ZzNVc He's selling a turning system, but the stuff on router bits starts with some info on carbide quality @3.00, cleaning @ 4.50 and honing @5.45.

There's another piece from Highland here which takes a fairly similar tack: http://www.highlandwoodworking.com/careandsharpeningofrouterbits.aspx They suggest Eze Lap slips which come in a set with more grades than the basic red and blue: http://www.highlandwoodworking.com/eze-lapdiamondpaddleset.aspx

Fairly routine honing sounds like a good move, in that he seems to suggest that grinding can remove a lot of material - the idea being to keep the bit in decent shape by cleaning and lightly dressing it for as long as possible.

Here's a video clip of a (maybe large workshop) level machine in use that grinds router cutters and other cutting tools, with a link to the company afterwards. There's a variant that does shaper cutters too:

http://www.youtube.com/watch?v=5QIC4RAimiM&NR=1&feature=fvwp

http://www.universalsharpener.com/us550andattachments.html

ian

[Tom Walz]

I really like the DMT dia-sharp 3 Grit Kit
Great for pocket knives if nothing else.

[Rick Potter]

OK, I went out and looked. I am using the set Tom mentioned. It's called EZ Lap, by DMT. Ian's link to Highland woodworking shows it. Mine has three paddles....250, 600, and 1200 grit. The new ones apparantly come with four grits.

I don't really consider what I am doing as 'sharpening', it's really 'lapping', just touching up the flat part a bit, which gives you a sharper edge, where the cutting happens. Getting the pitch/resin off is pretty important too.

I do it about like the video from Legacy shows, but with running water to keep the paddles unclogged as much as possible. I also clean the paddles with a scotch brite sponge from time to time.

Works for me. No expert here, just doing what the guy selling them at the show said to do, with the addition of the running water. After watching the Legacy video, I think I will try it his way, using a pan of water.

Rick Potter

[Don Morris]

Did anybody catch that "Eliminator chuck" the Legacy person in their video sliped onto the PC router? I hate changing bits in my PC routers. And what was he meaning by "Remember to balance it" when you first put it on? I'm going to research that now.

[Rick Potter]

I have one, and it works fine. Maybe I just got lucky putting it on. I assume that 'balancing it' would just mean trying it and twisting it about in the collet till it runs the smoothest.

I had an early model which vibrated the router. Returned it and got this one. The only disadvantage to using it is that a couple longer router bits, like the multi purpose one, will no longer go low enough in the table to use the upper part.

Rick P

[glenn bradley]

I too use the EZ Lap or DMT plastic sticks: http://www.rockler.com/product.cfm?page=2414&filter=sharpen They have been serving their purpose so long I think they were $9 a set when I bought them. If you've done some serious damage, this is a great and inexpensive little ttol although I use it mostly for Forstners: http://www.leevalley.com/US/wood/page.aspx?p=32954&cat=1,43072,43089