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It all has to do with the run-out/direction of the wood grain I guess. I just excavated channels on my headstock last night (shaped exactly like yours Hesh, and I do mean exactly... check it out, my picture here is the headstock ruff shaped) The only problem spots were the tight radiuses on the bottom and the top dome, which is to say, the endgrain. I think tear-out is more problematic with softwoods, though.

I'm no expert but maybe just scoring the line with a Gramil? That's what I used last night, just the gramil,and I can't praise it enough.


   

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From my experience, I tend to do climbing cuts when cutting the binding and purfling channels on the top and back. I have not bound a headstock yet, but I can see where you might want to do one there as well.

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Look at a router bit (rRegular style; spiral bits have less of an issue when it comes to wanting to rip junks of stuff out). Look at how the two blades are set, and visualize how it rotates. Now imagine, it the blades are biting into the wood (ie, regular cut), what the grain is doing; the times you risk tearout is when the blades are pushing the grain out and away from the piece you're cutting; like putting a chisel in, and prying. So you want to approach those areas from the other side, which means, since you can't turn the bit upside-down and reverse it (well, you could put the router in a router table for some things), a climb cut.

Look at a guitar top for a simple example: you tend to work from the peaks (bouts) to the valleys, because that way you're keeping the grainlines pushed 'in' toward the piece, not outwards. And that involves a climb cut in some situations.

With your headstock, much the same applies: approach the pointy wings in a regular cut (especially), and you very much risk a piece flying off. Go on. Ask me how I know this . My reccomendation: get a piece of scrap wood (any real wood will do, something splitty is good), and try cutting a few test-headstocks.Mattia Valente38789.5029166667

As my grandfather use to say “you make a lot less waves and better time paddling down stream"

Oh yes. one of the benifits of multi passes is less push off. One of the benifits of less push off is a more square ledge. The smaller the bit the greater affect push off has. the other is a smother cut.

The standard routing maxims of "outsided cut = counter-clockwise" and "inside cut = clockwise" just don't hold up too well in the curvy world of guitarmaking. Here's how I think when making router cuts (from above) on compound curves: always go downhill. On a guitar body, the bouts are the "hills"; so, from either lower bout you'd route toward the waist and toward the tailblock. From either upper bout, you'd route toward the waist and toward the headblock.

Hesh, for your headstock, think of the peaks of the wings as the "hills" and route from there down to the nut (on either side), and along the sides until it starts to flair out again (from the photo, I can't really tell if it does flair toward the top. If it does, stop at the "valley" and start over from the other "peak." If it doesn't, you're good to go along the whole side). Now, here's where it gets a bit confusing. The curved top of your headstock could very logically be thought of as a "hill," but you should always route "down" end-grain (the same reason the tail-block area of the body isn't a "hill"). So, in this case, the upper wing peaks are the "hills" and you should route from there to the center-line. Basically, the whole concept works around knowing where your end-grain is, and finding the "hill" that leads down into it.

Why does this work? Well, it's easy to imagine why routing into short grain could grab it and pull out the wood ahead of the cut because wood wants to split along its grain lines. The cutter can hit a softer grain line and literally push out a chunk of wood before it can cut it. So, since the cutter is always turning the same way (clockwise, when making a hand cut), how does changing the direction of the feed make a difference? Because if you use a climb ("downhill") cut, the wood that might have been chipped out by the spin of the bit has already been cut away. Hard to explain without a diagram.

How come it's called a "climb" cut? Because when you move the router in the same direction as the spin of the bit (clockwise, on an outside cut), it happily grabs the wood and wants to "climb" in the direction of the cut. That terminology made it difficult for me to grasp the whole concept until I started thinking of the climb as "downhill."    Warning: ALWAYS concentrate mightily when making this cut, because the router can VERY EASILY jump out of your control and ruin your work, ruin your router, or ruin your body parts!

Thanks guys, great information here, i'll sure reread this when i'm ready for that step of the build.
Thanks

Serge