graver geometry confusion

I've been looking at my flat graver and it occurred to me that when the flat graver is rotated to use just the point to cut a line, it looks like a square graver with a parallel heel on only one side. A square graver with only one parallel heel won't cut very well, and since one can cut a line with the point of a flat graver these gravers don't have the same geometry. My problem is that I don't understand why they don't have the same geometry. The bottom and side of the flat graver that create the cutting point are at 90 degrees just like a square graver. Only the bottom of the flat graver has a heel so that when it is rotated to cut on the point there is essentially a heel on only one side. I'm obviously missing something significant here. Can anyone help? I'm really struggling with graver geometry and trying to understand the different results that can be achieved in the metal based on changes in graver geometry. I appreciate any help.
Diane Belk

Diane,
I'm not really sure I understand the question 100% but let me try to answer.
Yes, a flat turned sideways is similar to a 90 but with only one heel. BUT.. A flat is designed to be used mostly laying flat and/or tipped slightly. Trying to cut a straight line like a border with a flat isn't recommended. It can be done but s really tricky.
On the same token, a 90 degree tipped over is very similar to a flat. Many engravers use a 90 to achive the look of a flat. It's personal preference. The 90 usually won't cut as wide of a swath however.
The bottom line is you need both gravers.
Clear as mud????

Rex

a flat graver heel is equal the entire lenght of the cutting portion. The heel facet looks like a small rectangle

a 90 degree graver only has a very small portion of its potential cutting portion with a heel on it. The heel facet looks like a small triangle

Hi Diane, Imagine this:
a flat is ground to use a whole flat of the tool to cut with. The square is designed to cut on just the corner of the blade. The flat is a square chisel type tool. the 90 degree or 120 degree square is faceted on the corner like a diamond shaped tool. It is designed to cut both ways, right or left with one tip. the flat will cut and has two points, right and left and you have to alternate from one corner to the other to cut right or left curves.

The square graver is used for line engraving, the flat is used primatrily for bright cutting or wide flared cuts in a scooping fashion.

The square has a keel with two belly flats with a corner of the tool up and a corner down requiring a facet on each flat, where the flat is using one whole side of one flat.

Hope this helps.

Ron S

As I see it the main difference to the question between the two is the angle of the face. If you use a flat as a square the face is not perpendicular to the cutting angle but on a slant. As far as the hell mentioned on a square graver, This is true unless you are using a parallel heel in which case the heel runs up the full length of both sides and thus looks like a two sided flat.

Thank you everyone for taking the time to give me your feedback. It really helped me. I thought flat gravers were used for line engraving as well as square gravers, and it was just a matter of personal preference whether a person used a flat or square graver for line engraving. It seemed that cutting with the point of a flat graver would require orienting the flat graver in such a way that the flat graver would look like a square graver with a parallel heel on only one side. I thought this would create a lot of heel drag on the side without the other parallel heel. My question came from my misunderstanding of the way a flat graver is used. Thank you all for clearing this up for me.
Diane

lots of neat tricks can be done with a flat. here's just one of many dozens !

What would happen if you put a small heel on each side of a flat graver? Sounds like something you would try just to see.

Rod