Circular Bow for Guitar- Help in perfectioning it.

Construction and repair of Classical Guitar and related instruments
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H.H. Alejandro
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Circular Bow for Guitar- Help in perfectioning it.

Post by H.H. Alejandro » Thu Nov 09, 2017 1:55 am

Hello!, so this is a product of my own invention, Ive always wanted to get that acoustical bow sound on a guitar or bass, so i made a PROTOTYPE, I have to say that i never knew about the hurdy gurdy, but i ended up buying a custom size wheel from some friendly crafters!
What is new about this, is that it will let you have resonance on any string you want (you can play 1 to 3 strings at the same time), and unlike the hurdy gurdy, not all strings are played at the same time. I attached some pictures for you to see. you control the mechanism with your right hand, by sliding the wheel to whatever string you like and by rotating the wheel with your ring finger (or multiple fingers (from middle finger to pinky)), the cilinder is for support, you can place your thumb in it, or above it, and it is for applying pressure on the string or lifting the wheel.
I recently added a ring on the lever of the wheel (the one you rotate with your ring finger), to help rotate easier.
I can get sound out of it but the design needs to be more "stable", or not more stable, but completely static when using it (without it moving sideways a little or tilting the other), it needs more precision and Id add more rings or one whole ring where you can put your fingers from the middle to the pinky on a longer lever. Also the wheels rotation is a little bit crooked.
Can someone help?! with all these things fixed Im pretty sure it will work!
Thank you! (this is my surprise to you guys! I wish it could have been working fully by now, but its still in progress).
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Steve Ganz
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Re: Circular Bow for Guitar- Help in perfectioning it.

Post by Steve Ganz » Thu Nov 09, 2017 2:15 am

Try leather on the wheel.
Steve

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H.H. Alejandro
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Re: Circular Bow for Guitar- Help in perfectioning it.

Post by H.H. Alejandro » Thu Nov 09, 2017 2:32 am

HEllo! thank you for your reply! but what for? you mean to change the guitars timbre with that? because when it comes to timbre there is no problem!

vesa
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Re: Circular Bow for Guitar- Help in perfectioning it.

Post by vesa » Thu Nov 09, 2017 6:50 am

What about a sound sample Alejandro?
Vesa Kuokkanen

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malc laney
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Re: Circular Bow for Guitar- Help in perfectioning it.

Post by malc laney » Thu Nov 09, 2017 9:49 am

A sound sample! What fun is there in that ? I've justb made a travel trumpet out of a washing machine hose a bit of plastic milk bottle , it sounds like Sweep having a panic attack.[if you don't know who Sweep is i suggest you check your Larousse]

UKsteve
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Re: Circular Bow for Guitar- Help in perfectioning it.

Post by UKsteve » Thu Nov 09, 2017 1:14 pm

I have an E-bow: What would be the benefits of your device over that?
(I understand that the E-bow only works on steel strings, but that is what you are using in your pics).

malc laney
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Re: Circular Bow for Guitar- Help in perfectioning it.

Post by malc laney » Thu Nov 09, 2017 2:57 pm

In machinus complexus Heathicus Robinisimus has a few pointers , especially those he graciously attributes to Leonardus Vincissime.Very practical.

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H.H. Alejandro
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Re: Circular Bow for Guitar- Help in perfectioning it.

Post by H.H. Alejandro » Thu Nov 09, 2017 4:13 pm

Sound sample: Ill try to make a sample, but i accidently messed up the lever when trying to make a new ring for it, so turning the wheel no longer works, it sounds pretty neat i can tell you that! As soon as i have another one Ill upload one, but i dont know how much time it will be.

E-bow: well the main difference about an ebow and this is the tone or the sound it produces, ive never used an ebow but i ve heard it, and this sounds very different. i dont know the playing possibilities of the ebow, but with this bow you arent very limited.

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H.H. Alejandro
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Re: Circular Bow for Guitar- Help in perfectioning it.

Post by H.H. Alejandro » Thu Nov 09, 2017 4:15 pm

also, the hurdy gurdy people told me about trying to use gut strings on a guitar to play with this bow, i think you could use any type of string, from gut to nylon to steel and this would work, but i havent tried!

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H.H. Alejandro
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Re: Circular Bow for Guitar- Help in perfectioning it.

Post by H.H. Alejandro » Thu Nov 09, 2017 4:17 pm

I made a motorized bow too, but i just like it mechanical a whole lot more, the reason is that you dont have to plug anything in to charge or to have power in this.

malc laney
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Re: Circular Bow for Guitar- Help in perfectioning it.

Post by malc laney » Thu Nov 09, 2017 4:26 pm

Exactly!

Alan Carruth
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Re: Circular Bow for Guitar- Help in perfectioning it.

Post by Alan Carruth » Thu Nov 09, 2017 5:05 pm

I've made a few hurdy-gurdies. Plywood wheels are a drag; although they stay round the edge roughness is an issue. Plexi wheels work well enough, but the best I've found was a wood 'tire' on a ply wheel. A thin piece of wood (walnut is good) is bent to fit around the wheel, making something like 1-1/3 turns. Then you scarf off the ends to fit together for an inch or more, and glue the tire on. A large hose clamp makes a good clamp. Once it's on scrape it round.

It's hard to avoid triggering torsional waves in the strings, particularly large ones. These can 'phase lock' with the transverse waves you're trying to generate, and steal all the energy, producing a loud squeaking sound. I suspect that a plain G string would be hard to control in that way. Violins often use a soft damper on the bridge top, particularly with the high E string, which cuts his down pretty nicely. It's not so much of a problem with wound strings as the windings themselves help damp torsional waves.

You might find you'll get more sound out of the guitar if you put in a sound post. It's hard to say; violins use a taller bridge and that helps as well. The bow is driving the string from side to side, and the top of the instrument works best when it's moving up and down. The post immobilizes one bridge foot, and converts a tall bridge into a bellcrank, with sideways motion at the top of the bridge producing vertical motion at the other foot.

On the other hand, that may not be such an issue. Guitars are actually far more efficient at turning string force into sound than violins. If you did bow the strings on a guitar 'vertically' you'd probably have the world's definitive collection of wolf notes. Maybe making it the less effective way is the right thing to do.

The wheel has a tendency to saw through gut strings pretty quickly, so the old hurdy-gurdies used to have some cotton on the string where the wheel hits it. This totally messes up the intonation, which is one reason the 'frets' on a hurdy-gurdy are adjustable. It also eases up any problems with the wheel going out of round, which used to be quite an issue before the invention of plywood. The usual solution to that was to cut the wheel as a section of tree trunk, with the axil running through the center and the annual rings concentric around it. You have to find a wood that has almost no shrinkage difference between radial and tangential or it will check radially. I think they used mulberry.

There are descriptions of a keyboard hurdy-gurdy, called a 'giegenwerke', iirc. No originals survive, but a few years ago somebody made one. I saw a video on line of it, and it's quite a sound. The key to the mechanism is that there is a wheel for every pair of strings, and the wheels are always turning. Pressing a key on the keyboard presses the string onto the wheel so that it can sound; with a smooth round wheel you only need an infinitesimal gap to silence the string. I suspect they used metal strings so that they could do away with the cotton. They may well have had a damper on the string between the fret and the nut to stop it sounding as soon as it was released. The one I heard did not seem to speak quickly, which is to be expected, but for slow and stately tunes it offered an organ-like sonority that was interesting.

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H.H. Alejandro
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Re: Circular Bow for Guitar- Help in perfectioning it.

Post by H.H. Alejandro » Thu Nov 09, 2017 5:23 pm

ok i just saw the "giegenwerke", if its the one made by Akio Obuchi, pretty neat! Ill see if i can get a luthier here in mexico to recreate my bow with less errors... would you be open to this? if you are please send me a private message!

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