Builds

[David Perry]

Post your F-F-Fiddle builds here! I'll get us started with the first F-F-Fiddle EVER made. It didn't really work, but it validated the concept. These pictures were taken on July 14th, 2013.

 

[David Perry]

Here's the third version, the first with a truss rod. I played this version at Portland's Mini Maker Faire in September, 2013. 

[David Perry]

Then things got more awesome. Some changes were made for playability, and I made 'The Red Violin.' This is the version that you early adopters made. This particular F-F-Fiddle went on a bluegrass cruise in February 2014 and I got it signed by some rad bluegrass fiddlers. I still have this F-F-Fiddle, and have mostly avoided tearing it down for parts...

[David Perry]

This F-F-Fiddle was assembled for the How-To in MAKE Magazine #40. After MAKE was done with it, it went to live at the 3D Printing the Future exhibit in Tampa, FL's Museum of Science and Industry.

[David Perry]

Now, the most recent F-F-Fiddle build -- printed in ProtoPasta's carbon fiber PLA! It sounds better! I was under a major time crunch and had printer problems which made it very difficult to build two of these in quick succession. One was sponsored by ProtoPasta for iMakr's store opening night in NYC, another I took to the White House Maker Faire. These pictures were taken on June 10th, 2014.

[Ben McCandless]

Disclaimer 1: I have almost zero musical aptitude.  Designing and building stuff, though . . .

Disclaimer 2: I have a 6 year old daughter who is taking violin lessons.  This is a crucial piece of information that relates to essentially everything else in this post.

----

When I first saw the F-F-Fiddle in a hackaday article, I was intrigued, but some quick checking showed that the bed on my printer (a MakerBot Replicator 2X) was too small to print either the neck or the bout, and the only version available was a 4/4 size.  (Too big for the little lady!)

Anyhow, that was it for a while.  Then my latest Make Magazine showed up, and there in it was the F-F-Fiddle again!  I must have had a weak moment, because I showed the article to the girl, and asked if she wanted one.

"Can you make me a pink one?"

"Yes" (I happen to have a spool of pink filament for exactly this situation.)

To be fair, I was probably to busy giggling at the image of the girl, with braids, playing a pink electric violin in a subway station, with a set of effects pedals.  Like I said, I had a weak moment. . . 

My next step was to contact David and ask nicely for access to the CAD files.  He promptly shared the Autodesk 360 files, and I got cracking!  Sort of.  Actually, after some flailing on my part, I realized I was going to have a really hard time modifying the existing version into a 1/2 or 1/4 size version that would fit the little girl, so I fired up SolidWorks, (my CAD package of choice) and got started CAD-ing up my own version.  I did a bit of research on measurements for each violin size, and here's the single most useful collection of information that I found: http://woodsoundstudio.com/setup.htm)

I had a couple of non-negotiable requirements:

• Must use OTS tuners that do not cost $130 per set.
  
• Must use the same K&K pickup as the F-F-Fiddle
  
• Must be a parametric design that can be modified to fit any particular size player.
  
• It must have pink parts.
• All printed parts must be small enough to print on a MakerBot Replicator 2X.

In addition, I had a couple of other things I wanted to do compared to the F-F-Fiddle design:

• Use the truss rod as part of a truss structure, not as a beam in bending.
• Eliminate as many fasteners as possible, and make the assembly self-aligning.
• Hide the balls at the end of the strings.
• Eliminate the need to solder the 1/4" jack.

The jury's still out on the last optional requirement, but I think I got the rest!  Here's a picture.

This is strictly the first pass - There are still a few things to do:  Specifically, the pickup hasn't arrived yet, so I'm waiting to see how it will be integrated with the rest of the unit - I will likely need to add some material to make everything fit. In addition there are a lot of little improvements to be made - tweaking hole sizes and the like.  However, this version tunes up nicely, and I can play "Twinkle, Twinkle, Little Star" on it, which is about the limits of my abilities. 

Here's some specific notes: 

• I printed this out of ABS, which may not be ideal.  PLA might be stiffer, which would probably yield a better sounding instrument.  On the other hand, the truss rod design (see below) may remove a lot of this from the equation.
• The CAD totally parametric model, so you can modify it to whatever size is needed.  I've nominally set the measurements for a 1/2 scale violin, but I think the body is a bit short for that - I'm going to be talking with someone who knows more about violins to discuss that.  
• I used Schaller M6 Mini tuning machines, which are substantially cheaper than the Gotoh Stealth units.  
• A big difference from the F-F-Fiddle is the structural design - there is a truss rod, but it's held in compression (not bending) by the strings on one side, and a thick music wire - which is tensioned by that 5th tuner under the chin rest - on the other.  This also lets me get rid of the nuts and bolts - the fingerboard and the body are self-aligning, and the tension on the music wire pulls everything together, making them unnecessary.
  

I'll make another post when everything is working and all of the improvements have been implemented.  I'll also post the current version of the CAD files so that people can print their own versions in whatever size they choose.

The miniature Fender amp was mostly gratuitous.

Best Regards,

Ben McCandless

[Ben McCandless]

So here's the follow up.  I finished the little girl's violin (1/2 scale), installed the pickup, and everything seems to be working just dandy.  Here's a picture of the finished item:

I'm pretty happy with how this one turned out - I've posted the STL files on Thingiverse (Link: http://www.thingiverse.com/thing:430479)

And then, because my little boy wanted one too (and because I can't stop) I started from scratch, built a parametric model that would automatically scale to whatever size violin I was willing to enter the parameters for: 4/4, 3/4, 1/2, 1/4, 1/8, or 1/16.  My first test of this new design was to build a 1/16 scale violin, shown here:

Here's how the two compare:

I haven't put a pickup in the small one yet, but I went ahead and strung it up and tuned it, and it sounds fine.  

For future plans:

• Get a pickup into the blue violin to verify that everything fits.
• Update the chin-rest sizes to something that is moderately appropriate for each size of the new CAD version.  After this, I'll release all the CAD on Thingiverse.
• I've committed to building a 4/4 size violin for my daughter's violin teacher, which will hopefully be my last build for a while.  My only concern at the moment is that I don't have access to a 3D printer with a large enough bed to print it right now.
  

-Ben

[David Perry]

AWESOME work! I know you'll get a bunch of makes -- interest in smaller violins is high. 

Schedule pending, I'm planning to make one before Portland's Mini Maker Faire! Lots of kids come by to play the F-F-Fiddle only to struggle with a full size instrument. I'd also like to try your truss assembly and to see how the fastener-less assembly feels. That is all super clever and looks really well executed!

Oh, and thinking about a parametric model for a string instrument makes me weak in the knees! I may build a string number parameter for additional strings on top of your design...I have always wanted a five string...

[Ben McCandless]

For the record, I received a pickup and installed it in the little guy's violin:

The installation was actually easier than with the 1/2 scale version - I've made some improvements to the voids and things fit better.

Anyhow, he seems very pleased with it, and drags it out for visitors all the time.  I've also posted the Thingiverse files here: http://www.thingiverse.com/thing:457018

I'm still working on a full scale (4/4) version, but have been distracted by other times - the only thing stopping me from printing one right now is that I need to get the chin rest scaled to fit an adult.

-Ben

[Taavi Burns]

I built mine! :)

I printed on a MakerBot Replicator 2 located at the Toronto Tool Library East location http://torontotoollibrary.com/ . The Scotch Exterior Blue tape was really awesome as a printing surface. It feels a bit like rubber/vinyl. I printed both parts on the same strips of tape; next time I'd replace them, as I think the bout's raft didn't stick as well, leading to some of the raft bonding to the bout.

The neck printed out really cleanly; the bout had a lot more hair on it. I wonder if there are slicer settings that would let you get a slower print, but with more predictable "hair seams" (where the print head skips from one tower to another in a layer). That would make them easier to clean up. I also noticed that the layers weren't always even, particularly around the machine head holes. I suspect the slicer changed directions when new holes came up, and the printer wasn't perfect at lining things up when moving in different directions. It probably gets a lot of use, so it could just be that the belts are getting loose.

I found that all the holes were a little too small: the strings were a bit hard to get through their holes, the drill rod needed a LOT of prodding, and the machine head sleeves did need to be drilled out. This kind of thing was the case with another thing I printed in regular PLA on that particular printer, so it may be something quirky about this particular printer, or maybe there's some setting that can be tweaked. The pilots for the machine head screws worked perfectly though. I didn't hear any scary noises while screwing them in. The machine heads themselves also fit perfectly. The jack had no wiggle room at all. I had to shave the sides of its slot down, but left them as a pressure-fit, since the nut wouldn't have turned anyway. I'll chalk that up to my jack being significantly larger than the one designed for.

I accidentally left a small tab on the drill rod (see the album below), and that let me use the drill rod as its own drill bit, with a little help from a pair of vice grips. Rememer: TWIST not PUSH! (well, a bit of both)  ;)

Parts list:
https://docs.google.com/spreadsheets/d/179m9drMQz87-0DkCkORPrP9kHZOq23TcsZ6VBbdc4AE/edit#gid=0

Pictures of the build:
https://www.flickr.com/photos/jaaaarel/sets/72157647011762069

Here's what it sounds like plugged into my PreSonus AudioBox 44VSL, with no effects added (warning: horrible technique, and my playing is out of tune; it's been 20 years since I played!):
http://taaviburns.ca/f-f-fiddle-taavi.flac

Some of the sound might be a result of the bow I'm using: it was in a case with a student-quality violin in my father-in-law's (unheated) garage (in Toronto) for 20 years…and the bow was left tensioned! So it's lost some hair, and there's only so much tension you can get on the hair before the wood is straight. :( There's also no sign that it's ever been rosined, but that'll get fixed quickly. :)

David: Thanks for sharing the design, and the joy of building your own instrument! :D

[David Perry]

Taavi -- you're welcome! I am SO much enjoying reading about all of y'alls builds, derivatives, and feedback, so thank you for building a F-F-Fiddle, and for the detailed report.

Your issues with your Rep2 sound familiar -- definitely could be belt tension. They are notoriously bad with backlash in the belt system. Even though my belts are tight, I have configured custom Makerware profiles that adjust for my backlash. Without the backlash adjustment my truss rod is WAY too tight and I run into some of the other issues that you had.

I still have trouble with inserting some strings. Some strings have more thread wrapped around the base of the string and simply don't fit, while some neck prints (especially if I use a new mat'l or make settings changes) have a bit of goober in the string holes. There's no reason those need to be as small as they are.

Glad your machine head screws went well. I often end up with one screw stripped (and it's always the same one, there must be something funny about the print path there), but due to the nature of the loading of the strings I don't feel worried about it. It's another good reason to go to a different tuner (like the Waverly uke pegs).

Another builder loaded the drill rod up in his drill, and used that to twist! Very clever. 

Thanks again for these great details, this kind of information is really helpful! 

[Bill Carson]

Hi everyone,

         work has interrupted play so I decided to post the progress so far.

I am in the progress of modifying the 3D model to take a 10mm metal dowel that has been cross drilled and tapped to take a threaded rod.  The threaded rod has a brass bush glued on one end with a screw driver slot in it.  I chose 5-6mm studding as long as it can fit down an 8mm carbon fibre tube.  The neck still needs work to change the existing hole to take just the threaded rod and a recess to accommodate the brass bush.  Locating pins align all the parts, the threaded rod doesn't need to be cranked down hard as it will only cause the PLA to creep, this should make a very stiff assembly.

Its still all on the drawing board and I have a few other designs I am trying out in CAD first.

[Bill Carson]

A little further work and experiment.  PLA machines well if you print it dense and keep it cool.  To get back to Davids printed style violin I am testing some printed dowels and cutting thread in them and replaced the brass bush with a PLA conical bush that will fit in a tapered hole, like old fashioned violin tuners.  This spreads the load across more surface area than a step so reducing the load on the PLA.  Still a chance it could split across the printed layers, so the ideal would be to print the top of the neck vertical to take advatage of (for want of a better term) the printed grain.

This is something we tend to forget with 3D printing, change the density for different part applications. Another thought for you David the flutes you run down the truss rod, spiral them round it.  This will add denser material where you need it all the way round the rod without too much unsupported overhang.

[John Porteous]

Hi Guys - I recently printed parts using a Lulzbot TAZ 5, PolyMAX PLA, and used the suggested settings from Thingiverse.  Printing went great & the parts looked good.

When the violin was taken to install tuners we experienced "delamination" or layer separation (picture attached).  Curious as to whether the suppleness of the PolyMAX PLA may be in play.  I chose it over regular PLA as it is generally stronger.  I'll be re-printing with 'normal' PLA as a test.

Also curious to know if increasing density (more infill and/or more shells) is an option or whether that would degrade sound quality.  

Sincerely appreciate any input/thoughts.  Many thanks, jp

Ps - as a side note - there were no thermal factors (e.g. - not left in car, etc.).

[David Perry]

Bummer! 

Looks to me like poor bonding between your layers. I've never had cracks like that in my F-F-Fiddles, but I've had layer separation on other parts when my temperature settings weren't quite right. For me it's usually an indication that I'm printing too cool.

Denser infill might help, but that may just help to cover up the real problem. I don't expect you'll get too much of a change in acoustics, but it may cause more warp on the parts.

Also, make sure you're drilling out the bushing holes. They're designed to be undersized, and if you force the bushing in you could cause a split.

[John Porteous]

Thanks David - I’ll bump the temp on the next go round - also appreciate the note about the bushing holes!

I’ll let folks know how it goes.  Best, jp

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[Andrew Murrell]

Boom!

Printed on a MendelMax 1.0 (remote bowden extruder, E3D V6 hot end, and a highly modified y-axis with 16mm linear rails/bearings) using Inland PLA from Microcenter. Total print time was roughly 30 hours. I ended up printing the neck with 30% for more rigidity/strength. Assembly was done with ZERO sanding/preparation of the printed parts (I wanted to see how fit and finish was without sanding). The next step is to pull it apart and sand the fingerboard. Playing through a Fender Mustang I V.2 is really neat. I need to brush up on my violin skills (I played for 15 years and stopped almost 10 years ago) before I post up a video of how it sounds.

Thank you David for such a cool object to print!!!

[David Perry]

WOOT! This thing looks awesome, Andrew! Nice color and print, and I love those gold Stealths. You're welcome! I'm really happy this gets you playing the violin again.

Hi to the new folks that I just approved. There are a few of you that had to wait a while for approval -- my apologies! I don't know how I missed your applications...but I hope you can still find some useful info here as you build your F-F-Fiddles. Please post up your builds on this thread, I love to see them!

-David