A relatively little discussed sharpening question . . .

[Michael Ray Smith]

Hard to believe, I know. Actually, I found an old thread mentioning that Derek had posted a video on the topic, but I don't know where to find it.

Not too long ago, I bought a couple of L-N joinery floats, and I've found all sorts of uses for the face float. I've sharpened it a couple-three times using either a 6" XX-slim file. (I tried a 5" XX-slim, and it works okay, but the teeth of the float are deeper than 1/2 of the width of the side of the file. If you want to use the file going both directions without overlapping the areas on the file, you need the 6".) This last time, I can't seem to get the float as sharp as I have before. So. . . what techniques do you use for sharpening floats?

[Matthew N. Masail]

Good question. I think one more thread like the convex bevel thread and I might kill my virtual self.

[Steve Voigt]

If you are sure you have gotten the teeth sharp, but the float is still not cutting as it should, there are two main problem areas to check.
First, the teeth may not be at even height. I joint my floats just as you would joint a saw, but you want to be very cautious here and only take the tiniest bit off the top. I suggest you take 3 or 4 light passes with a mill file and then inspect. If your teeth are not even, you'll see little flats on only a few of the teeth. Take a few more light passes, and then file only the teeth that have flats showing. Then test the float and see if that fixes the problem. You can do this in several stages until you have most of the teeth working for you.
Second, you may have relaxed the rake of the teeth too much, so the float is scraping, not cutting. Have you seen Larry Williams' video on sharpening floats? I think it's on youtube. Anyway, the teeth should have 5-10 degrees of positive rake--the opposite of the rake you use on a saw. You should be able to see this just by looking at the float from the side. I recommend using a rake guide, just as you would use on a saw. Mike Allen had pictures of a simple homemade rake guide on his recent saw-sharpening thread.

[Michael Ray Smith]

I wondered about the rake. I'll check. Actually, I did joint it. . . wonder if I took too much off and haven't completely removed all the flats. I'll check that, too. Thanks.

[Derek Cohen]

Hard to believe, I know. Actually, I found an old thread mentioning that Derek had posted a video on the topic, but I don't know where to find it.

Not too long ago, I bought a couple of L-N joinery floats, and I've found all sorts of uses for the face float. I've sharpened it a couple-three times using either a 6" XX-slim file. (I tried a 5" XX-slim, and it works okay, but the teeth of the float are deeper than 1/2 of the width of the side of the file. If you want to use the file going both directions without overlapping the areas on the file, you need the 6".) This last time, I can't seem to get the float as sharp as I have before. So. . . what techniques do you use for sharpening floats?

Hi Michael

No video, but I did a brief demo when reviewing the LN Joinery Float ..

http://www.inthewoodshop.com/ToolReviews/The%20Lie%20Nielsen%20Face%20Joinery%20Float.html

Just treat the flat as if you were sharpening a rip saw ..


http://www.inthewoodshop.com/ToolReviews/The%20Lie%20Nielsen%20Face%20Joinery%20Float_html_ 5dda2af6.jpg




Regards from Perth

Derek

[Michael Ray Smith]

Thought I'd pull up this old thread and let you know what I found. Turns out Steve was right -- I had relaxed the rake a bit in my earlier sharpenings. I put my Veritas sharpening jig on the file and set the rake at -10 degrees. (It's not actually marked for negative rake, but it's pretty easy to figure out how to do it.) It cuts far better now. Much obliged!!