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im trying to figure out a method for cutting a rosette channel that will work best for me. im totally burned out on making jigs right now and want to do something cheap, easy and accurate so i can get on with the guitar building. i came across grumpy's method on line (i think cumpiano does something similar in tradition and technology) where there are holes drilled in a base plate to a router or laminate trimmer that allow different radius circles to be cut. i guess my question(s) is if you use a lam trimmer (or a fixed base router), how do you plunge and keep things accurate? no big deal for the rosette because you can start and stop under the fingerboard, but what about cutting out the sound hole? am i over thinking it? i have both lam trimmer and fixed/plunge base routers. what would work the best?

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sweat the small stuff.

Heath:
The simplest way to cut the soundhole out is using a popsicle stick with a pivot hole drilled on one end and a #11 xacto blade jammed through the stick on the other end at the proper radius. Works like a charm! Mikey

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The Biggest Little City, Nevada
www.hammondguitars.com
I love building guitars!

Does your lam trimmer have a circle cutting jig? I'm assuming not or you probably would be using it right now. My dremel came with a little circle cutter that no one suggested using but ended up working well for a piece of aluminum and plastic. No micro adjustment, I just crept up on the final dimensions. Could you make a very simplified circle cutter out of scrap? There are several "hand" jigs that use cutter blades, making something like this would be pretty simple to fit your lam trimmer I think. Lots of ways to go about it apparently.

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Chansen / C hansen / C. Hansen / Christian Hansen - not a handle.

Christian

I now use a jig modeled after one showed on Sylvan Wells web site because it is more versatile and very easy to adjust, but the trimmer with multiple holes in the base plate works well; I have one like that too. To cut the sound hole I simply lift the bit off the sound board when I start the machine and tip it in, you don't need a plunge base for this. Test on scrap, there's nothing to it, you'll see!

The popsicle stick method works great too, that’s about as simple as it gets, jigwise. That or a drill press with a fly cutter or one of drill press jigs that LMI sells. Or a regular circle cutting attachment for your trimmer or Dremel. Or… Lots of ways to do this for sure.

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Rian Gitar og Mandolin

I have used the dremel circle cutter attachment that I ordered directly from Dremel for cutting ukulele sound holes and rosettes, and it works just fine. For less than $20 it will work just fine. http://www.amazon.com/exec/obidos/ASIN/B000HI5WTY/ref=nosim/dremelaccess-20


Hope that helps!

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Tracy
http://www.luthiersuppliers.com

Simple. Free. Effective. Accurate. What more can you ask for? Don't worry about the "plunging"; it wn't matter, even at the soundhole, since you'll clean that up when you sand it to round it off.

You could make the popsicle stick thicker by using a paint stir stick, as long as its a good one.

I use a dremel and there are bits that fit the outside B&W perfling rings perfectly, so it makes it a bit easier.

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Here is what a Parlor Guitar is for!
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all excellent information. thanks for the replies.

grumpy, thanks for addressing my concern about plunging. im planning on binding the soundhole, would you say that it is still not a concern to "tip in" since you need a more precise fit?

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sweat the small stuff.

With the lam trimmer base on the pin, you can lower the bit straight down into the wood. No need to tip it. I get a totally clean cut with no sign of where the bit went in. Do some test cuts and you'll see. Piece of cake.

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Todd Rose
Ithaca, NY

https://www.dreamingrosesecobnb.com/todds-art-music

https://www.facebook.com/ToddRoseGuitars/

thanks for the heads up todd. maybe the only down fall of this forum is that if im unsure of something, ill sit in front of a computer instead of a work bench and wait for someone to give me the answer instead of going out and making some saw dust. so thanks for the info and encouragement from all.

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sweat the small stuff.

I use double-sided tape, securing the soundboard to the workboard below, so that everything stays put once the sound hole is cut.

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Todd Rose
Ithaca, NY

https://www.dreamingrosesecobnb.com/todds-art-music

https://www.facebook.com/ToddRoseGuitars/

The center pin in my jig goes through the soundboard and into another hole in the workboard below. This workboard and the top are both clamped to the workbench, so nothing moves when the soundhole is cut.

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Rian Gitar og Mandolin

Here's a circle cutting jig that is pretty easy to make and works very well. It's what I use and it's trustworthy. I always cut the soundhole on the drill press with a fly cutter at LOW rpm.
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.

thanks for the heads up on securing the soundboard when cutting the soundhole out. not doing so would be like trimming a tree and standing on the branch you are cutting off! not pretty.

terence, i was pretty much sold on making a circle cutting jig like the one mario posted above (and i still may because it is super simple to make and use), but your jig would not take that much more effort to create and looks like it would be easier to adjust to different radii. thanks for posting that, it was totally helpful.

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sweat the small stuff.

Here's mine. It is quite easy to make. As I mentioned, instructions on how to make one can be found on Sylvan Wells' web site.

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Rian Gitar og Mandolin

arnt, that is a sweet little circle cutter. i did see that on sylvan's site, but i kind of always dismissed it because i thought the material might be difficult to get a hold of. i know youre in norway, but did you find your material somewhere i might have access to? actually, i havent even tried that hard. i just know they dont have it at local hardware stores.

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sweat the small stuff.