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Looking for either a commercial one, or plans for a DIY one, Looked at the LMI one . didn/t know what to make of it ?? Your experiences pro an con would be appreciated if you bought a commercial one or made one . Need one to go from 2 -5in Thank you.

Primitive/simple but I know the 1st one works just fine with a down spiral bit.

http://www.acousticguitarconstructionfo ... p?f=7&t=15

http://www.luthiersforum.com/forum/view ... 77#p504977

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Ken Cierp

http://www.kennethmichaelguitars.com/

I assume you mean a "manual" circle cutter as opposed to one that utilizes power tools. If so, here is a link to Leonard Letourneau's site. He makes very good ones. I have one myself.
http://www.letourneauguitars.com/handcrafted-tools/

Here is a photo.

And there is this one

http://www.luthiersforum.com/forum/view ... 59#p469259

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Ken Cierp

http://www.kennethmichaelguitars.com/

Michael very nice rosette cutter . Len says call for pricing . How much are they in us $$??. No . I am strictly looking for a manual one . The routers/air die grinders make way too much noise for me . I have 3 routers I want to quickly cut uke s. holes without setting up my air /die grinder. Thanks

The last one posted is a Boone design and no motor. Sorry in our shop manual means not using the CNC machines.

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Ken Cierp

http://www.kennethmichaelguitars.com/

Tnx

You know, a circle cutter can easily be made from a fly cutter, the kind that is used in a drill press. Just skip the drill press, swap out the drill portion and put in a 1/4 brass rod, and make a simple base for it to sit in. Or, alternatively, put it in the drill press and turn it by hand.

I've used it this way a number of times and it works very well. Just sharpen the blade very well.

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Expectation is the source of all misery; comparison the thief of joy.
http://redrivercanoe.ca/

Tnx doug, , got one an used it on the drill press a few times yrs ago.It/s been sitting in the garage for yrs now. Sounds like a good idea

I reground the cutter from 45 to 25 deg. an tried it on an old piece of1/4 sawn wrc.It works ok . The cuts are not as clean as I would like lots of tearing on the wrc it/s 25 yrs old. Will try it on scrap spruce tnx

There's always the 'popsicle stick trick': drill a hole for a center pin in a thin stick of hard wood, and stick the point of an X-Acto knife through it at the proper distance out to make the cut. This works surprisingly well. You can control the depth of cut pretty easily, and with a nice new blade it will make a clean cut. Just remember to always cut from the work toward the waste.

Regarding the drill press fly cutter: Unplug your drill machine. Slip the drive belt off your drive pulley. Chuck the fly cutter into the machine jaws very securely.

...Now...

With your wood stock securely clamped and with one hand on the quill plunge mechanism, just start lowering your fly cutter with one hand while turning the chuck with the other hand. It works GREAT.

Or...use the popsickle stick method, as previously described.

Or...use a home made circle cutter, as previously described and illustrated.

I have done all of the above.

Someone on a forum (this one?) alerted us to this tool. I've not used it, but their other stuff that I have works very well and is good value. Probably best to change out the pointy pivot for a pivot shaft, though.

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Trevor Gore, Luthier. Australian hand made acoustic guitars, classical guitars; custom guitar design and build; guitar design instruction.

http://www.goreguitars.com.au

They are expensive, about $600 CDN I think ($450 USD. Leonard uses 2 blades, 1 to make fine cuts for a rosette channel and the second to chisel the waste out of channel. Extremely accurate. Considering the high cost, this tool is a little bit of an overkill for its purpose and very much so for just sound holes.

TNX michael, an trev, I don/t care for the drill press method, am sure It would work for others . I/ve used it a few times .The popsicle I have not tried.Len/s tool is wonderful . but past my current budget. I do have a similar circle cutter from L/N it works ok. I saw a nice hand made cutter in the book by J. romanillos, also 2 other english guitarmaking books courtnall an doubtfire. Time to break out some wood an try my hand at tool making

FWIW, here's a link to my circle/purfling cutter in the OLF Tutorial Archives. It's a little different, but it was fairly easy to make. I still use it to cut out sound holes. viewtopic.php?f=10102&t=13581%22

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Waddy

Photobucket Build Album Library

Sound Clips of most of my guitars

Alan, I'm sure I'm just being more dense than normal today, but could you expand on "cut from the work toward the waste"? My exacto blades have a bevel on both sides so although I -think- I remember that that unbeveled side should be against the work and not the waste, that wouldn't seem to apply here.
Thanks, Mike

OK: the 'work' is the part of the top you're going to keep, outside of the rosette and in between the rosette and the hole. The 'waste' is the part you're routing out for the rosette. The cutter should always be moving away from the work, and toward the waste. That way, if it decides to follow the grain lines it's not cutting into the part of the top you want to keep. Thus: for the outside border of the rosette you start cutting on the center line of the top under the fingerboard and run the knife downthe treble side of the hole to the place where it's going parallel to the grain. Pick up the knife so it's not cutting, and go to the center line at the lower edge of the hole and cut up toward the bass side of the hole to the wide part. Reverse the knife, and stating at the top and bottom complete the cuts. The inside edge goes the other way: start from the widest part of the hole and go to the center line on each side.

When cutting the channel for the rosette I like to make the inside cut first, and to size, and then make the outside cut a bit in from where it 'should' be. Clean out the channel, and see if the rosette goes in: it shouldn't. Sometimes commercial rosettes vary a fair amount in width, though, ad you may find that parts of it will fit. In that case you can hold it is with the inside edge tight and scribe around the wide parts with the point of the knife. If it's all too small it's fairly easy to make a little bit of a trim cut. This has the added advantage of removing the dings you made around the edge when you slipped with the hand router or chisel.

Trevor, that is what I use, and I replaced the point with a 1/8" diameter dowel pin. Works great.

Bob

Thanks, Bob. Apologies for not being able to remember it was you who told us.

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Trevor Gore, Luthier. Australian hand made acoustic guitars, classical guitars; custom guitar design and build; guitar design instruction.

http://www.goreguitars.com.au

Tnx waddy for the tutorial on circle cutter!

Perhaps the cutter might just need to be sharper?? FWIW I always had nice clean channels with no tearout when I used to use a drill press fly cutter. 45 degree angle worked for me. Sharp enough to split hairs. Plain chisel cut type grind. (stone the sides of the cutter too)

Greg I inherited my general circle cutter abt 25 yrs ago the blade on mine is curved on the outside and has a skew bevel edge set at 25 deg . Is your blade flat on the outside and ground flat at 45 deg like a chisel ?? Thanks a photo if you have one would be good ..That could be my problem ?? The way the blade/bevel is ground

Yeah, ground flat in the front like a chisel back. I am cheap so used the other side of the stock cutter, but you can buy 3/16" tool steel easy enough.

The Popsicle stick method does indeed work quite well. I remember seeing that trick in Cumpiano and Natleson's book and thought it was stupid till I tried it years later. The only difficult part about it is getting the radius measurements just right but it cuts perfectly when using a fresh blade. I just use it in a continuous circle too but make sure to take very light passes to depth.