Whiche difference in heel

[Willem Parel]

To the engravers who have both systems Id' like to ask the question.
Is there a characteristic difference (not the optical) in the parallel heel you produce with the Lindsay templates and the heel you get with the GRS dual angle fixture???

Willem

 

[Ray Cover]

All other things being equal, ie. same belly angle, same face angle, same heel angle, etc., etc...............

I find that the parallel heel lets me roll the graver farther without issues. I tend to use that kind of heel anytime I am cutting things that require bright cutting like script lettering or flare cut scroll, etc.

The traditional triangular heel tends to be a little stronger (at least it seems so to me) I tend to favor it when cutting standard scroll or other designs that do not require much in the way of rolling the graver.

Now this can turn into a case of comparing apples and oranges if you do not consider the other angles involved in teh geometry such as the belly angle of the graver. What I mean is the heel on a graver with a 116 degree belly is going to be stronger than the heel on a 90 degree graver simply because the wider belly angle adds strength to the whole geometry of the graver.

Ray

 

[Brian Hochstrat]

What Ray is saying I have found to be true as well. One thing I will add is I find the triangle heel to be more stable in the cut and less apt to want to porpoise or shift side to side. I like the parallel heel for background removal, because of the full cutting edge.

 

[fegarex]

Another thing to mention is you can easily do full length heel with a dual angle sharpener. The angles just need to be adjusted to suit the tool you are using. For instance a 105 degree graver is set at 45 degrees for a full length heel.

 

[Red Green]

Brian,

I have little experience so your statements surprise me. I do not understand the dynamics of why one graver heel shape would be more stable within a cut than one of the same width and length and angle in the cut. Is this true in power, push and H&C?

Bob

 

[Brian Hochstrat]

Bob, I am really not sure the dynamics of why either. It is just what I have experienced and my statement is totally anecdotal, hence the wording that I used, " I find". It is possible that others experience the exact opposite. But I mentioned it because if I find it be more stable, there is a good possibility others will experience the same.

 

[Ray Cover]

I have notice the same thing. For some reason it shows up more for me on wider belly angles than on narrow angles for example a 90 with a parallel heel doesn't seem show this affect as much as a 120 degree belly with a parallel heel.

I have a theory as to why this happens but I am not a physics professor or an engineer so take it for what its worth.

I think one thing that comes into play with this is the surface area of the heel. For the same length heel the parallel heel has a much greater surface area than the traditional wedge shaped heel. Since a cut is made by finding that sweet spot or running angle where the downward pressure from the face is counterbalanced by the upward pressure from the heel angle, having a greater surface area on the heel seems to make that running angle more critical. You get outside the zone in the least little bit and the graver either wants to rise or dive.

That may not be the only factor at play. The fact that a 15 degree heel on a parallel heel is presented at a slightly different angle to the work being cut may also be a factor in this.

Here is what I mean. On a standard 90 degree graver (with a 15 degree wedge heel) to get the heel you set you post angle for the lift of 15 degrees and the roll angle at 45 for one side of the 90. For a 90 degree graver with a parallel heel you still set the post angle at 15 for the lift but you have to turn that roll angle on over to about 55 degrees (if I remember right).

That extra ten degrees on the roll angle changes the angle at which the cutting edge is presented to the steel it's cutting.

 

[Red Green]

Brian and Ray,

I think I'd take your 'feeling' about engraving over a professors theory, so please don't think I'm questioning your experience.

“Here is what I mean. On a standard 90 degree graver (with a 15 degree wedge heel) to get the heel you set you post angle for the lift of 15 degrees and the roll angle at 45 for one side of the 90. For a 90 degree graver with a parallel heel you still set the post angle at 15 for the lift but you have to turn that roll angle on over to about 55 degrees (if I remember right).*“

Did you state that backwards? I thought a parallel heel was at the same angle and was just parallel across the facet and did not change the width angle of the cut.

Bob

 

[Ray Cover]

The lift is still 15 degrees but the angle in relation to the face is changed when the graver is laid over that extra few degrees to make the heel run all the way up the face. This changes the angle that the cutting edge is feed into the work.

Ray

 

[Roger Bleile]

I generally favor the parallel heel after using the wedge shaped heel for about 30 years. The main reason is that I get no burr or heel drag on curved cuts no matter how tight the turn. I don't know if this is because of something about the way I engrave or not. I can cut scrollwork in any metal with a parallel heel and leave not the slightest burr to be polished off. I mainly use a Lindsay PC but when I use a burin it works the same.

Roger

 

[Andrew Biggs]

And then there is the no heel method that Phil Coggan and others use with such great effect.

I think a lot of it is what works for one doesn't necessarily work for another because we all have individual methods of attack. It's those slight variances that make all the difference. That and whatever you get used to doing over a period of time.

For instance, I don't have a lot of luck with carbides in steel because the way I use them they break a lot............and yet others swear by them for everything.

Cheers
Andrew

 

[Red Green]

Ray,

I forgot to account for the angle of the face, that put my head in a twist for a minute (had to get a bigger hammer:beatup. The more I think about this the more confused I get. If I have this correct a parallel heel is set from the face of the graver so a 120 degree parallel heel graver is 120 degrees from top to point on the face. So a 120 degree graver is 120 degrees and has a 120 degree heel and that gives it a triangular shape?

Bob

 

[monk]

a good reason to have more than 1 graver of the same size/shape. this way you can experiment and find what's just right for the way you work. good to have the same graver size/shape with different geometries for different cutting techniques or effects. i don't know about most folks, but i own a truckload of gravers-- and can always use more !

 

[Willem Parel]

Thank you all for the replay, I will experiment with both.
The reason why I did ask this is because untill now I always used a graver with the parallel heel.
But yesterday I sharpened a graver with a triangle heel and it felt different.
Indeed it felt more stable and I was able to cut nicer tapered lines, like shadow cuts.
Ofcourse this can be my lack of experience in engraving but I changed gravers and noticed still the difference.
For myself I will try a little more on this and see what type I prefer.
Thanks again for the answers.
Willem

 

[Kevin Scott]

Willem, my theory is the parallel heel is best for power or hammer and chisel. It has many advantages.
I have tried the standard Lindsay geometries and find they require quite abit more push power when hand pushing. Which leads to more slipping and control problems. Seems to me you have to go deeper with the parallel heel to get flare cuts. Went back to traditional geometry with about 45 to 50 degree working face angle, which is alot lower than the Lindsay geometry.

I do find that I can make very fine hairlines with good depth with the 96 degree Lindsay template. Better than with other geometries. But have more control problems on turns.

I am a amateur hobbyist push power only, with no lessons, so maybe I am doing something fundamentally wrong.

I should try the parallel heel with a lower face angle. Maybe that would be the best of both worlds for me.

 

[Red Green]

Kevin,

I am an absolute newbie but from my very limited experience it sounds like you're describing what happens when I have made too wide of a heel.

Bob

 

[Willem Parel]

I haven't done that much with the triangle heel but what i've noticed is that you can permit a little longer parallel heel without getting heeldrag with tight curves compare to a triangel heel.
But for me it's interresting to find out the difference in character of those type of heels.

 

[Kevin Scott]

Kevin,

I am an absolute newbie but from my very limited experience it sounds like you're describing what happens when I have made too wide of a heel.

Bob

Bob, went back and resharpened my 96 degree with the Lindsay template. Made heel about 1/64" versus before 1/32". Better control on turns, but still had the other problems. So it seems your thinking is correct.