New rosette cutter

RPA_Ukuleles

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Made a new rosette/soundhole cutter to use with a Dremel. Drew it up in Adobe Illustrator and cut the parts from 1/4" acrylic on a laser. Had to etch away a recess in the back of the base to accept the retaining nut on the pivot pin. The nylon wingnuts tighten easily and don't vibrate loose. I threaded the tool plate with a 3/4"-12 tap and the Dremel screws right in. I wanted to make one of acrylic so I could see everything while working - but will likely have to polish out fine scratches regularly. Works great!

rosettecutter_zps9dc6dea2.jpg
 
Real men use these:

SpirographBox86.jpg
 
That looks like a piece of kit bought from a manufacturer for loads of quids. Well done.

I never could finish that flippin' owl with the Spirograph though. The green biro never lasted long enough, the pins would slip out of the cork board and then youd get a big blob of ink smearing all over the page.
"Hey Mum, here's a picture of half a wonky owl, with a large blue ink smear"
 
I did make the thumb wheels under the tool plate - also out of acrylic, then threaded for the 1/4-20 machines screws. But I would like to replace those with brass thumbwheels if I can find some. I have thought of some design mods already so version 2 will likely have small knobs both front and back to hold while in use. There is already a small hole to accept a knob in the front, but I think one behind the tool would be nice too. Had also thought about going with a finer thread on the screws, like a 1/4-28, but this is able to adjust about a thousandth of an inch at a time, so it might be good as is.

Hey, I loved my Super Spirograph when I was a kid. Well, at least until the little Spin-Art machine came along!
 
Very nice design. Looks like something made by the styling department of a classy company.
Now how about one to fit a laminate trimmer? I've always found that dremmels allow that little bit of wiggle at the bit that can cause gaps in the rosette.
 
Fixture looks great......... only problem I see is the acrylic....... we have and do make a lot of jigs, fixtures, and templates from acrylic and other plastic type materials. Think you will find that if the bit ever hangs or snatchs it will crack the fixture at the bolt holes. I'd recommend polycarbonate but it want be cut very easily with a low powered laser (less than 100-150 watt) to cut or mark or to pocket. If we are going to cut or mark polycarbonate we usually use the cnc, the carbon in the poly tends not to laser or cut well.

Nice addition to the fixture would be a fine adjustment screw and knob.

My two cents.

Blessings,

Kevin

Waldron Instruments, Inc.
 
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Agreed Kevin. I don't have that much power and I wouldn't laser cut polycarbonate anyway - just too toxic. And while I can't imagine straining the tool enough to break the plexi, it is pretty cheap to cut new parts if one should break. I thought of machining one on the ShopBot rather than the laser. But I do like the polished edges the laser gives.

I have drawn up a way to add a screw adjustment. But I'm just gonna use it for a while to see if that's even necessary. Sometimes simple is best.
 
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