	Gramercy
	Finest abrasives.
	Microbevels front and back.
	Use a jig.

	Copyright (c) 2002-09, Brent Beach

Gramercy D2 Iron

Test Summary

Gramercy D2 Iron

This is my first test of a D2 steel plane iron. The specification of D2 looks a lot like that of A2, but with more Carbon, Chromium and Vanadium.

Both blades were tested using the standard sharpening procedure, through 200 passes of the standard 4 foot long douglas-fir board. The test was repeated immediately for both blades. The four sets of results were basically the same.

The blades tested were more durable than A2, but less than M2. They had a better looking edge at the end of the test than A2, not as good as M2.

Pro:	A very durable iron that retains a good edge. This is probably as good as you can do short of using High Speed Steel blades.
Con	A little harder to sharpen. However, you can't get a more durable blade unless you work a little harder sharpening it.

D2 and Abrasives

It seemed to me that D2 is harder to grind and hone, although I have done no rigorous testing of this. During later testing for initial sharpness and hand grinding using bench stones, it seemed to me that the D2 blades took longer than even the M2 (high speed steel) blades. However, the resulting edges were just as sharp as blades made with other steels. The Gramercy people comment on honing difficulty: "D2 as an alloy is tougher than A2, and slightly more difficult to sharpen. However, we typically hollow grind everything and use Norton water stones for final sharpening with no real worries. We have found that D2 seems to not sharpen well on Shapton ceramic stones, but on regular Norton, Naniwa, Ice Bear, and King stones they hone up fine."

The Test

February 2005.

The blades, one 2" and one 2-3/8", arrived with a larger than standard primary bevel. I ground them both back to 25 degrees on the belt sander using a 60 grit AlO belt. This took a while, since there was quite a bit of metal to remove. After grinding almost to the edge, I worked the bevel at 29 degrees using 15 micron abrasive then returned to the grinder with 120 grit AlO to complete the grinding of the primary bevel. These blades are quite tough - be prepared with fresh abrasive if you need to grind.

Primary angle at 25 degrees, first microbevel at 29 degrees using 3M SiC 15 micro abrasive, second microbevel at 31 degrees using SiC 3M 5 micro abrasive, third microbevel at 32 degrees suing 3M CrO 0.5 micro abrasive.

A theory has been put forward that the plane used may affect the results -- a better plane may result in a better test outcome. These blades are quite thick -- 0.116" -- so must be tested in a plane with a wide mouth. That meant a relatively modern Record #4 for the 2" blade (all the tests of thick 2" irons use this plane), but a Stanley #604-1/2 (Type 7) for the 2-3/8" blade (my first test of a 2-3/8" wide blade). I may retest the 2" blade in the #604-1/2 (no problem since I am using only the middle inch of the blade during the test) as part of an attempt to test this theory.

Rather than use the results of the first test after grinding, I used both blades for a full 200 pass test, then went through the 3 step honing procedure and did the 200 pass test again. The results shown here are for the second test. Both blades showed some edge chipping on the first test that I attribute to edge damage during the factory grinding, or perhaps during my grinding. Grinding considered harmful.

The Results

All images are of the front bevel at 200X magnification.

IMAGE CAPTURE CHANGE!

Starting with this test I have changed the way the images are collected from the QX3 microscope. In the past I used the software that came with the microscope. Lately I have been using the freeware program Irfanview instead, thus avoiding some post processing the original software did that reduces the clarity of the image. The result is a sharper image. These pictures are therefore not strictly comparable, in clarity, to earlier images.

This change has affected the conversion factor used to convert pixel, the individual picture elements, into inches. That is, converting from the apparent width of a feature in an image into actual size in inches. Now, each pixel in the image corresponds to 0.000076". Formerly, each pixel corresponded to 0.000071". This change was an error on my part, not a deliberate decision.

As delivered.

2" blade.

Ragged edge, interesting bevel appearance.

I could not get a reflection from this edge. It appears to be very smooth, with what scratches there are running parallel to the edge. My light setup does not catch scratches in this direction, it would appear.

In spite of lack of visible scratches, clearly needs honing.

2-3/8" blade.

Scratches in two directions. Not a bad edge, needs honing before use.

Freshly sharpened.

2" blade.

The black line is a scratch I put on the blade with a carbide scribe. This mark allows me to make get pictures of the same part of the blade each time. The mark was put on the blade before the 5 micron and 0.5 micron abrasive steps, so is partially honed away.

The scratch across the 0.5 microbevel about 1/3 of the way up from the bottom appears to have been caused by a larger piece of grit on the 0.5 micron abrasive. It will appear in all pictures, but does not appear to have weakened the edge.

2-3/8" blade.

The 4 bevels are pretty clear in this image: 0.5 micron third microbevel right at the edge showing few scratches,

the 0.5 micron third microbevel at the left edge showing almost no scratches,
the 5 micron second microbevel next, running just past the tip of the scribe mark,
the 15 micron first microbevel next, running just past half way across the image,
the primary bevel (120 grit belt) thereafter.

After 100 passes along 4 foot douglas-fir board.

2" blade.

Very narrow wear bevel, about 3 pixels wide, with good edge quality.

There is a small defect just back of the edge near the top of the image. It looks like a bit of lint and might well be. It did not come off with the usual rubbing to clean the blade (t-shirt material), so there is some defect there.