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View Full Version : Getting an edge on a Lucas gl1 french curve scraper



Dueane Hicks
01-02-2020, 12:23 PM
I bought a Lucas gl1 French curve scraper; Since I only have a tormek and not a traditional grinder; Holding this monstrosity while grinding seems to be an incredible challenge! Plus, I'm not sure if it is supposed to be sharp; or have a burr on it?
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Eugene Dixon
01-02-2020, 12:35 PM
IIRC Glen sharpens these with a fixture that holds the tool vertically above the Tormek. He may show it on one of his videos. I sharpen the one I have with a CBN and grind for a burr. I use a Wolverine platform. One of RoboHippy's platform should also work.

FWIW, a Tormek seems to be Glen's go to sharpening system. Or it was when I was there.

John K Jordan
01-02-2020, 3:33 PM
I sharpen all scrapers on a CBN wheel with a flat tool rest. With a Tormek it takes too long to reshape the edge so you need the angle to be set perfectly to match the existing bevel. To set jigs and rests, one good way (if you haven't tried it) is color the edge with a sharpie, set the rest as close as possible by sight, then hold the tool firmly on the rest with the bevel against the wheel (with the switch off) and turn the wheel a tiny bit by hand. It's easy to see if the resulting scratch is across the whole bevel and make tiny adjustments until it is.

These days I make plastic setting gauges which save a lot of time. This one is for grinding 90 deg edges on hand scrapers.

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BTW, I've sharpened scrapers on my Tormek but I prefer a 600 grit CBN wheel on a bench grinder. (I use a 1200 grit CBN wheel on the Tormek to sharpen my spindle gouges.)

A scraper needs a burr to work properly. There are differing opinions on whether to use the grinder burr or use a burnisher to raise a burr. Having done both, I now always work this way:
- Sharpen the scraper and ignore the burr
- Remove the burr with an extra fine diamond hone or the leather honing wheel on the Tormek
- Burnish a burr with a carbide burnisher (I use one of three, depending)
- When the burr becomes dull, hone and burnish again

For me, the burnished burr lasts a lot longer than the burr from the grinder. It can also be burnished to be delicate or aggressive.

JKJ

Dueane Hicks
01-02-2020, 9:03 PM
That's some good information. Helps alot!

John K Jordan
01-02-2020, 9:44 PM
That's some good information. Helps alot!

I love these negative rake scrapers - I use them on every bowl, platter, and boxes and forms where

This is my design of a curved scraper. With a straight grind on the end instead of a curve I think it's more useful in flat or barely curved sections on platters and such. I grind both sides with the same bevel so I can change the direction from "right hand" to "left hand" by burnishing the burr on one side or the other. I grind mine from Thompson scraper and skew steel. I don't mount them in a handle but use them unhandled.

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I grind another NRS edge on the tang end for double duty.
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The straight end in use on the wings of a squarish platter:
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After using these on the small platters I go to hand scrapers off the lathe and then to fine sandpaper (off the lathe), usually 320 or 400 or finer.
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JKJ