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Folks - In the past, I have been band sawing out pegheads and getting them to finish shape with rasps/file/sandpaper. In an effort to speed up the process, I made a 3/8" acrylic template which I made to be screwed to the peghead. On my router table with a 1/2" straight flush trim bit, I routed the peghead using cushioned push blocks from my jointer to keep the piece flat on the table and under control while pushing it into the bit. Even though the amount of material was minimal that I was removing, when I got to the endgrain on the top of the headstock, it grabbed the piece violently and took a big chunk out of it... so I made a new neck and it did it again! Not fun....

What bits do you recommend for peghead template routing? Do most of you use a router-table or fix the neck and use a hand-held router? If you use a router table, how massive is the jig that you use to hold the neck if you use a router table? Any pics? Recommendations?

Thanks, Peter

How are you feeding the stock into the bit? Normal feed or climb cutting? Climb cutting will cause a lot of chatter and cause tear out as well.

I also make sure I have no more than 1/16" of material to remove when using my router table to route my headstock shape.

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Hi Peter.

After the exact same thing happened to me a few times, I decided to leave the extra wood on the sides of the headstock while routing the top of it. This way, when chunks are taken off, they are taken off out of wood to be cut off. Once the top is shaped, I do the sides.

Hope this helps!

EDIT:



Maybe me definition of 'climb cutting' is wrong, but to me climb cutting is the safest way to avoid tear outs. Although you have to hold on to your router tight since it will want to move forward on its own.

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Alain Moisan
Former full time builder of Acoustics, Classicals and Flamencos.
(Now building just for fun!)

Climb cutting is when you feed the wood into the router and the bit is spinning in the direction of the feed. Yes this can cause the wood to run away on you. This is the most common type of cut on a shaper as long as there is power feed which really holds the material against the fence. If there is only slight pressure when climb cutting the chatter that can happen can cause tear out as the bit moves in and out and you wrestle with the piece or router to stay in place.

A normal cut, feed at a moderate speed makes a much cleaner cut and when routing end grain shouldn't cause tear out. Depends on grain direction too, but routing end grain shouldn't be an issue.

That's my understanding and experience anyway. Want a real router adventure? Just climb cut most of your pieces and it can be a wild and crazy ride.

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Well...that's what I always do!

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Alain Moisan
Former full time builder of Acoustics, Classicals and Flamencos.
(Now building just for fun!)

I am only taking off about a 1/16th+-... Also, I am not holding onto my router. That's mounted in the table. I am holding onto the stock pretty firmly with push-pads from my jointer. It's not causing tear-out, it's grabbing my piece and trying to chuck it across the room! The rest of the headstock gets routed out like cutting through soft butter... Should I be using the smallest diameter bit? Biggest?

Take a look at this Youtube video for an alternative way of cutting out your peghead. It takes a bit longer to make the cut but you will always have all 10 fingers when done!

Big bit is good, a bit slower speed. I use a 3/4" 2 flute flush cut.

The reason the piece is being grabbed and trying to throw it across the room is because you're climb cutting. Try running the piece the opposite direction. You should have that problem.

Well Alain my friend, I'm glad you have success with climb cutting your pieces. I certainly hope you don't get the router running away on you and causing any damage to yourself or your work. Sounds like you have experience with your router but for some, that would just be a terrifying experience to have the router ripped out of there hands because they are running it in the wrong (well, opposite) direction. There are times to climb cut but for the most part, running a router in the "normal" direction is best.

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"We have to constantly remind ourselves what we're doing....No Luthier is putting a man on the moon!" Harry Fleishman

"Generosity is always different in the eye of the person who didn't receive anything, but who wanted some." Waddy Thomson

I like to bandsaw headstocks pretty close to shape, then robo-sand them on the drill press, and then go over them again with a fresh sharp pattern bit in a router table. After shaping with the robo-sander, there is just the slimmest skin for the router to take off, it basically just shaves off the sanding scratches from the robo, leaving a nice finish that barely needs any detail sanding, and more importantly to me, the router doesnt get grabby and chippy with such a small bite to take.

It is an extra step, but fewer steps than fixing tear out OR turning your fingers into hamburger.

I also really like the looks of Robbies trick, thats cool!

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Jordan Aceto
Ithaca, NY

When I first started template routing my headstock With a 1/4" plexiglass template I had a similar problem. I made a template out of 3/4" stock. Cut the peghead close on the bandsaw. Attach the template, and take it to the Robosander which leaves a very small ledge. Maybe 1/32" or less. Then finish off on the router table. I have had absolutely no problems doing it that way. The Robosander is totally safe. You can apply the same principle to other template routing operations.
Terry

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It's not what you don't know that hurts you, it's what you do know that's wrong.

If you're routing: the smallest bit you can use spinning the fastest you can spin it is safest from tearout, chip out, and chunk out. Abrasive methods are, of course, even safer. Robbie's method is quite clever, as well, and has most/all the benefits of the small cutter. You could do the same thing with a 1/8" cutter in your drill press (taking VERY LIGHT depth cuts!) and get a slightly better finish, letting the shank run against your acrylic template of course.

I use a 1/8" end mill on one-off headstocks where I don't want to fuss with the toolpath (though it is something to see watching a 1" cutter doing a headstock! )

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Bob Garrish
Former Canonized Purveyor of Fine CNC Luthier Services

After some help locating it from some folks here (maybe Chas Freeborn?), I bought what is essentially a 2.5" tall spiral power plane blade mounted on a shaft with a flush trim pattern bearing on the bottom for use in a router. Works great on end grain and runout.

I can't remember the source though and I can't find it in the archives or by google. Maybe someone else will remember and have better luck.

The entire purpose for climb cutting is to prevent tearout. There's no other reason to cut that way. But without a power feed, one should only climb cut when removing small amounts of wood and/or with pieces you have excellent control over and with hands well out of the way of the bit. It will certainly try to grab the work.

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Rick Cowan, a student and one of our members here, routed his headstock last night in class ....

We use a 1/2 inch thick baltic template bolted thru two tuner holes, countersunk. This goes face down onto the router table. I use a spiral 4 flute, 1/4 inch ball end, end mill as the bit, with a 3/8 template guide, in a table. We take only about 1/16 of height off in each pass, and use a climb cut for everything except the bass side of the headstock's top curve. It takes about 7-8 passes to cut the pattern thru, but there is no tearout, chipout, the bit doesnt chatter, and because you are only taking about 1/16 by 1/16 or so of material, not much for the bit to bite into and chuck the neck across the table.

Climb cutting is dangerous by hand when you are using a bit that is trying to take off too much material - even if the cut is only 1/16 deep, it still has has the full tickness of the headstock, and as such, too much wood to bite into, and then it grabs. I tried a flush bit once - not too good for my liking - tore the corner right off.

maybe Rick will see this and post some of the pix he took last night - the end product right off the table was ready to final sand. As I told 4 students last night -it may not be as fast - but it works everytime, and the results show you dont have to start over !!!

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Tony Karol
www.karol-guitars.com
"let my passion .. fulfill yours"

Robbie,

Thanks for the tip. Been looking for something like that!

Mike

Here's a general method that works well for me in many applications. It's based on the principle of suspending the router (with flush trim bit and large base) above a template to which the work piece is bolted. The fixture can be clamped to your workbench as you run the router. The first picture shows a classical head that will be later V-grafted to a neck, but the fixture can also be designed to accomodate an attached neck. The second picture shows how the slots were cut with the head mounted through the roller holes.

Hi all.

I know it's been a while but I tought I'd post this anyway since I was working on my peghead this afternoon.

When I mentioned I route the top of the headstock first, leaving the sides for later, this is what I meant. You can clearly see how the extra wood left on the sides would absorbe the chipouts, if any.

Hope it helps someone!

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Alain Moisan
Former full time builder of Acoustics, Classicals and Flamencos.
(Now building just for fun!)

In the video above (Robbie's), what size drill blank did he suggest? I cannot see it here at work and I was trying to order the parts..

Mike

I use a 4mm bit.

Thanks Robbie! Now whats 4mm in units of cubits?

Mike

Oh, and one more thing... do you find that 4mm is small enough for most inside curves and "corners"? Or do you do a little post processing with a chisel? Or rasp?

4mm. handles just about everything I need it for. If you have some super tight curves you might need to clean it up with a rasp or chisel.