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miche
06-22-2016, 02:01 AM
Can anyone recommend a circle cutter for ukulele size sound holes? I am having a nightmare trying to cut rosette channels. I currently use a crappy handmade one that does not give good results and has ruined a few sound boards. The dream would be the stew Mac set up or the proxxon Dremel tool and circle cutter but they are a bit out of the price range at the moment. So any recommendations in the UK would be greatly appreciated. I am no good at making circle cutters myself believe me I have tried. So any other ideas would be greatly welcomed.

Thank you everyone

Pete Howlett
06-22-2016, 09:22 AM
Tank cutter...

cml
06-22-2016, 09:47 AM
Something like this from your equivalent hardware store?
http://www.jula.se/catalog/verktyg-och-maskiner/elverktyg-och-maskiner/halsagar-och-dosfrasar/haltagare/stallbar-haltagare-181252/
It's only about 8...

Kekani
06-22-2016, 01:14 PM
Lmi
http://www.lmii.com/products/tools-services/rout/shape/drill/rosette/circle-cutter

Or a simple google search shows this:
http://www.jsbguitars.com/shop/guitar-building-tools/rosette-inlay/guitar-rosette-router-attachment/

Personally, I fight buying SMD tools because of cost, until I actually buy them, and wonder why it took so long for me to get. Then I sometimes get another MORE expensive tool thats even better. In the end, those with the most tools, WINS! Arfh argh argh. . .

fungusgeek
06-22-2016, 02:51 PM
I wanted absolute reproduciblity when cutting rosettes and sound holes. All these adjustable jigs mean that things will be different from one usage (adjustment) to the next. I took a class in using the laser cutter (which will cut 1/4" acrylic) at my local community college. I made up a base for the StewMac dremmel router base which has a series of 1/8 inch numbered holes, designed to fit over a 1/8 in pin in a backing board. I simply drill a 1/8" hole in the soundboard where the sound hole will be. The difference between one hole number and the next is a 1/10" larger diameter circle so the base will cut from 2" to 4" circles. I can now say that for some uke, I want a slightly wider rosette, so will cut from #9 to #14 with the sound hole cut with #7. If I like the result I can do exactly the same thing in the future, with no inexactness of 'adjustments'. Same thing every time, guaranteed.

miche - If you would like one, I can cut you one next time I am over at the community college, cutting other jigs and patters I have been thinking up.

9204492045

Kekani
06-22-2016, 07:31 PM
I wanted absolute reproduciblity when cutting rosettes and sound holes. All these adjustable jigs mean that things will be different from one usage (adjustment) to the next. I took a class in using the laser cutter (which will cut 1/4" acrylic) at my local community college. I made up a base for the StewMac dremmel router base which has a series of 1/8 inch numbered holes, designed to fit over a 1/8 in pin in a backing board. I simply drill a 1/8" hole in the soundboard where the sound hole will be. The difference between one hole number and the next is a 1/10" larger diameter circle so the base will cut from 2" to 4" circles. I can now say that for some uke, I want a slightly wider rosette, so will cut from #9 to #14 with the sound hole cut with #7. If I like the result I can do exactly the same thing in the future, with no inexactness of 'adjustments'. Same thing every time, guaranteed.

miche - If you would like one, I can cut you one next time I am over at the community college, cutting other jigs and patters I have been thinking up.

9204492045
You need to be selling these. 3/16" for me, though.

dofthesea
06-22-2016, 07:46 PM
I'll `take a 3/16" as well.

orangeena
06-23-2016, 03:20 AM
I use an old one of these.
http://i367.photobucket.com/albums/oo118/orangeena73/my%20ukulele%20stuff/hole%20saw_zpsk9lmjbxo.jpg (http://s367.photobucket.com/user/orangeena73/media/my%20ukulele%20stuff/hole%20saw_zpsk9lmjbxo.jpg.html)

I use a brad-point bit in place of the supplied one.
You can get them here (http://www.clasohlson.com/uk/Bosch-Hole-Saw-Set/40-9275) in the UK.
I should probably replace my blunt old one now I think about it, but it still does a fine job.
Max

Moore Bettah Ukuleles
06-23-2016, 08:23 AM
I wanted absolute reproduciblity when cutting rosettes and sound holes. All these adjustable jigs mean that things will be different from one usage (adjustment) to the next. I took a class in using the laser cutter (which will cut 1/4" acrylic) at my local community college. I made up a base for the StewMac dremmel router base which has a series of 1/8 inch numbered holes, designed to fit over a 1/8 in pin in a backing board. I simply drill a 1/8" hole in the soundboard where the sound hole will be. The difference between one hole number and the next is a 1/10" larger diameter circle so the base will cut from 2" to 4" circles. I can now say that for some uke, I want a slightly wider rosette, so will cut from #9 to #14 with the sound hole cut with #7. If I like the result I can do exactly the same thing in the future, with no inexactness of 'adjustments'. Same thing every time, guaranteed.

miche - If you would like one, I can cut you one next time I am over at the community college, cutting other jigs and patters I have been thinking up.

9204492045

Absolutely brilliant. I probably have $1000 invested in the 4 or 5 rosette/hole cutters I have but yours is so simple and foolproof (as long as you remember the numbers). I need one too but in 5/32". ;)

Biedmatt
06-23-2016, 09:14 AM
That is genious. If you are willing to take orders, I would like one in 1/8 inch.

SeanB1
06-23-2016, 10:19 AM
Brilliant! Here's what I made up for myself but there is little to no repeatability aside from markings on the base of the jig. Yours is really fantastic. As above, if you are taking orders, I'd like one in 3/16".9205192052

Sean

Moore Bettah Ukuleles
06-23-2016, 10:19 AM
That is genious. If you are willing to take orders, I would like one in 1/8 inch.

Fungusgeek needs to quit his day job and get busy with these orders! :)

Timbuck
06-23-2016, 10:30 AM
Fungusgeek needs to quit his day job and get busy with these orders! :)
That one is no good for you Chuck ...There's no flag on the Dremmel :rolleyes:

gspears
06-23-2016, 12:46 PM
If he does take orders, I'm in too. :iwant:

jcalkin
06-23-2016, 01:39 PM
For the first couple thousand H&D guitars we used a 1/8" pin that stuck up from piece of plywood, through the center hole of the rosette in the top wood, and into blind holes drilled into a full-size router bases. The router spun around the pin. I think the first upgrade was going to a 1/4" pin. The next was going to a Fadal CNC. The CNC is the cat's patoot, but the routers did just as nice a job.

Moore Bettah Ukuleles
06-23-2016, 02:03 PM
That one is no good for you Chuck ...There's no flag on the Dremmel :rolleyes:

You're right Ken. But he can sell those too! :)

fungusgeek
06-23-2016, 03:56 PM
When you guys say you want a "3/16" I assume that means you want 3/16 inch pivot holes, as opposed to 1/8 inch holes (?)
I'll modify the cutting diagram to make sure there is sufficient distance between the holes to expand them to 3/16 and let you know.

fungusgeek
06-23-2016, 04:07 PM
With 3/16" holes the holes in the base overlap in places if you want them close enough to maintain the 1/10" difference in the eventual diameter of the circle(s) which are cut between two numbers. however, I figured out that there are two sides to the base, so by spreading alternate holes out to different sides, I can achieve the same result with 3/16 holes. It is just that things are less than sequential, and you have to watch your numbers. See photo of drawing.

I about to go on vacation, so it will be a couple of weeks until I can get back to the laser cutter but:

Who might be interested in this base with the proviso that it uses 1/8 inch pins?
Who would be interested in 3/16 inch pins with the more spread out layout?

92053

Moore Bettah Ukuleles
06-23-2016, 04:59 PM
With 3/16" holes the holes in the base overlap in places if you want them close enough to maintain the 1/10" difference in the eventual diameter of the circle(s) which are cut between two numbers. however, I figured out that there are two sides to the base, so by spreading alternate holes out to different sides, I can achieve the same result with 3/16 holes. It is just that things are less than sequential, and you have to watch your numbers. See photo of drawing.

I about to go on vacation, so it will be a couple of weeks until I can get back to the laser cutter but:

Who might be interested in this base with the proviso that it uses 1/8 inch pins?
Who would be interested in 3/16 inch pins with the more spread out layout?

92053

So, too hard to do 5/32" holes? All my cutters have 5/32" pins. I guess I could drill out the 1/8" holes to fit or just switch to a larger pin. Problem solved. :) Please put me down for an 1/8 inched. It seems that the smaller holes would allow you to adjust it in smaller increments.

gspears
06-23-2016, 05:14 PM
What Chuck said. 1/8" would be fine by me.

dofthesea
06-23-2016, 05:36 PM
Ok I'll do the 1/8" as its easier to keep track

Kekani
06-23-2016, 05:56 PM
I'll take 3/16". I'm hoping the wider base fits a laminate trimmer or compact router (so I can plunge properly).

Suggestion: keep 3/16" handy; that's the "standard" pin you'll find all over the place, probably because SMD uses that size.

Briangriffinukuleles
06-23-2016, 06:00 PM
What a simple but great idea! I want one, Put me down for a 1/8". Puleez

Biedmatt
06-24-2016, 02:35 AM
BTW, this piece of kit has value and I am quite willing to pay you for it. The CAD layout alone for the laser cutter would cost someone about $100/hour and that doesn't get the machine set up nor includes the cost of material.

Titchtheclown
06-24-2016, 02:50 AM
My only suggestion for change would be to do the holes in 1/8th intervals rather than 1/10th intervals. That way using a 1/8th bit will allow you to do matching inside and outside diameters. Having holes at 1/16th intervals gives more flexibility, that is unless you are using 1/10th bits.

fungusgeek
06-24-2016, 10:38 AM
Interesting suggestion about using 1/8 inch difference between the holes radius, so a 1/8 inch bit (which is what I use) would cut inside and outside circles that match. Hmmmm...

I have an idea for a new layout that would permit an arbitrary size of pin, and would have the holes 'ordered' in a more friendly fashion. Have to do the math to figure out the hole placements though. Trig and simultaneous equations, but I think it will work.

At any rate, for those of you who would like a base, please Private Message me your name, address, and desired pin hole size.
The cost will be about $3.50 for the acrylic + $3.50 for shop time on the laser cutter + postage.

lauburu
06-24-2016, 12:36 PM
For those of us in far-flung places where postage exceeds the cost of the product, would you consider offering a downloadable CAD file for sale?
Miguel

mainger
06-24-2016, 02:01 PM
1/8 inch please :iwant:
:D

fungusgeek
06-24-2016, 03:44 PM
I have worked out a new hole pattern that makes a lot more intuitive sense, and allows for different sized pins and different diameter increments pretty easily. I have a calculation spreadsheet set up to compute the hole positions for different variables. Below is an example. I envision making bases for 1/8 inch pins, 3/16 inch pins, and one for Chuck with 5/32 inch pins. For any of these I can do 1/10 or 1/8 inch diameter increments for the eventual circles which are cut. So if you want a base, you will need to specify pin size and diameter increment.

As to a CAD file. This is all in Corel Draw, since the laser cutter is treated just like a printer. One prints from Corel and lines which are a red and a hairline thickness are 'cut'. Black lines (like the numbers) are just etched on the surface. It is real simple, and much easier to play with template wise that a full CAD system. If it is of help I can send out the spreadsheet which computes the hole positions if you want input to some CAD thing.

92066

Kekani
06-24-2016, 10:08 PM
If you made the base bigger, and did a double hole pattern, you could space it at 1/16". Then I know the base will be big enough for a compact router! Hint. . .

fungusgeek
06-25-2016, 04:45 AM
The base as it stands is 6" x 7" which should be plenty for a compact router base.


If you made the base bigger, and did a double hole pattern, you could space it at 1/16". Then I know the base will be big enough for a compact router! Hint. . .

Kekani
06-25-2016, 06:14 AM
Very nice.

lauburu
06-25-2016, 11:34 AM
If it is of help I can send out the spreadsheet which computes the hole positions if you want input to some CAD thing.

Thanks. That would be most helpful
Miguel

fungusgeek
06-26-2016, 08:00 AM
Thanks for all the interest and suggestions. I love making tools that make people's jobs easier. (I was in the software development business for the last 36 years, recently retired). I have settled on a design where the diameter increment between successive holes is 1/16 inch. This is a finer gradation that my former 1/10", and with a 1/8" router bit should allow inside and outside cuts to match well, allowing the jig to be used to cut both the rosette, and the rosette channel in the top. I calculated the numbers, made the drawing, and you get the expected really elegant pattern:

92153

I had to move a couple of holes to the 'other side' to leave room for the attachment bolts of the StewMac router base, but otherwise it is kind of neat to plug in a bunch of numbers and end up with a neat (though expected) spiral.

I will make these up with either 1/8" pin holes, or 3/16" pin holes. (easy to change the hole size). I'm on vacation through the 4'th of July and should be able to get to the laser cutter shortly thereafter.

mainger
06-26-2016, 01:53 PM
I calculated the numbers, made the drawing, and you get the expected really elegant pattern

Yep. That's what great maths often produces. Looks lovely, thanks for the hard work!

dofthesea
06-26-2016, 08:25 PM
Dude you totally rock for offering these up to the Luthier community.

Titchtheclown
06-27-2016, 12:24 AM
I have settled on a design where the diameter increment between successive holes is 1/16 inch. This is a finer gradation that my former 1/10", and with a 1/8" router bit should allow inside and outside cuts to match well, allowing the jig to be used to cut both the rosette, and the rosette channel in the top.


Actually it is even better than that. You can use any bit that is a multiple of 1/16 and by shifting the pin by the number of sixteenths that your bit is you get matching insides and outsides. Two holes for 1/8, four for 1/4, six for 3/8, eight for 1/2.

mikeyb2
06-27-2016, 05:26 AM
What's happened to the OP? Anyway, his original post states that he's ruined a few soundboards, so I would say it would be worth his while buying the Dremel/Stewmac base with circle cutter that he says he can't afford, rather than keep buying soundboards. Seems to make sense to me.

miche
06-27-2016, 10:31 AM
I am based in the UK and the cost of the stew Mac set up plus shipping to the UK is very expensive. As for the sound boards I have ruined they were not grade A expensive quality just nice enough for a basic instrument. I am very early on in my journey and still learning.
Thanks

mikeyb2
06-27-2016, 11:13 AM
I am based in the UK and the cost of the stew Mac set up plus shipping to the UK is very expensive. As for the sound boards I have ruined they were not grade A expensive quality just nice enough for a basic instrument. I am very early on in my journey and still learning.
Thanks
So am I. UK and one uke to date. A Dremel will set you back 30 maybe( the price of a cheap wood set),, the router base can be got for the price of 2 wood sets ( search online for someone in the uk who makes a similar one) and the circle jig can be made from perspex like below.
92201
do your sums and good luck.

Wildestcat
06-27-2016, 09:34 PM
I'm also in the UK and started out with a second hand Dremel from eBay (which I still use) and Dremels own plastic router base which has a 1/8 inch pin hole for circle cutting. It isn't brilliant as there is no precision control over radius adjustment, but I never cut a rosette or channel that wasn't usable, albeit using epoxy impregnated with ebony dust to provide some gap filling. I have to say though that when I eventually upgraded to a StewMac dremel base & circle cutter my results improved dramatically - money well spent in my opinion.
I actually found my Stewmac circle cutter base in stock on a UK woodworking supplies website, which worked out significantly cheaper than a direct import from Stewmac thenselves.
Good luck with your future builds!

Timbuck
06-27-2016, 09:39 PM
If just a sound hole is required, then chain dot drilling and sandpaper wrapped around a tumbler will do the job..Rosette channels are more difficult.

Briangriffinukuleles
07-13-2016, 08:26 PM
Fungusgeek' I received my circle cutter in the mail today. It is brilliant, beautifully made, fits perfectly on my Stew Mac router base. I will have some fun experimenting with it in the morning but for tonight I am just admiring its quality production, clear numbering and the excellent schedule of dimensions included. You really must get this trade marked or patented and get it on the market. Anyone cutting sound holes or rosette channels needs one, and I bet it will cut the rosettes as well. Thanks for a genius tool.

lauburu
07-29-2016, 10:36 AM
My template arrived today (the metric version) and I totally agree with Brian (above). It's certainly the best looking template in the workshop.
Many thanks Jon. It's a very generous contribution to the ukulele making community
Miguel

Kevs-the-name
07-30-2016, 03:35 AM
Although I responded privately, I should have commented publicly as well!
I received my template (in the UK) recently. Made to metric specifications.
I am yet to try it, but I am sure it will be perfect.
It looks great, and appears to be precision made. Thank you very much.