Thanks for writing and welcome to this forum. You have landed on a good spot.
Adding a heel to the graver is more or less the norm in North America, however, in Europe it is probably the norm not to add a heel. Excellent work is done with and without a heel.
I am sure others will respond to your post. I am pretty sure that world class engravers like Phil Coggan in Wales and Martin Strolz in Austria use gravers without a heel, but let them speak for themselves?
A heel is used to stop your graver tip from diving into the work. So in many ways it gives you some extra control.
Having said that, and what Rod says above, many European engravers do not use a heel. Rather they taper the bottom of the graver so it gives them some lift. One of the tricks when you don't use a heeled graver is to keep your hand very low.
It is one of those things that is personal preference and no right or wrong way of doing it.
I would suggest you try a graver with a heel and one without to see what you think of it. If you are a complete beginner then you may find a heel would suit you a little better and give you a bit more control. But like eveything there are no absolutes.
If you are learning and you work in copper maybe you can start with a half rounded graver , is more easy to control than the square for example, after that like Andrew say try with heel and without, considere that the lenght of the heel is important too
I am learning too and have found copper and silver the most difficult to engrave due to their extreme softness. Ive found mild steel the best.
Thats just my experience.
Felipe,Like Andrew said go with the heel for better control, a briun with out a heel take some practice.I like Martin Strolz's no heel geometry for fine detail on animals & bird anatomy.also like the onglette works great with H&C and briun. J.J.
Heeless gravers must have some sort of lift or I think it'd be difficult to use them, especially without breaking. As Andrew pointed out, some European gravers are given lift by tapering or rounding of the bottom. Stonesetters normally don't heel gravers, but I believe most hand engravers do.
All the above is great advice. I'd also like to add that a slightly longer heel will help you in cutting straight lines at a consistent depth and give you more depth control in general. However, if you go to far the heel can get in the way causing heel drag in tight radius turns. Once you get a feel for engraving, I'd suggest you also try a parallel heel.
No matter the heel, or in spite of, remember that control takes practice, practice, practice. Kind of like learning to ski or ride a dirt bike really well versus just making it down the hill. Mostly, keep it sharp.
I engraved for about two years without a heel and constantly fought for control. I was introduced to the graver heel in 1978 and it made an immediate difference in control. I always use a heel now except for banknote figures where all of the cuts are rather short.