Engineering the cheapest headless system

[shai-ga]

So basically I'm just looking to make an alternative for the few $200 and up systems on the market.

The problem to solve is fairly easy, talking about the body side only,
when the 1st fret side is: adapter (string holes), tightened to a C shape brass bar with 2 holes, connected to the neck, and a nut to set the strings right.

So the main 2 options to tune a string:
1. roll it on a screw \ rod, like a normal tuning post.
2. take it back to step up in tension, like the regular "drawers"

Obviously a drawer looking part is a hard one to manufacture, so I went with the following idea, currently using a normal bass bridge for saddles, but that might be solved in the future as well.

1. Fluted angle aluminum bar, drilled for mounting holes, also drilled for tuning screws. (electrostatic powder coated in black)
2. 4 Socket cap M4 screws, tuned by allen wrench.
3. 4 springs
4. 4 locking nuts, coming from the front.
5. 4 barrel nut (flat surface = constrained rotation) + drilled for strings, when the ball
end is held by the barrel nut body.

I believe this should work pretty good, but what can you say about the tuning precision and movement?

The progression of the screw threads should be close enough right?

I mean, ABM surley use these kind of screws for their systems, maybe M2\M3 to be more accurate.

Any thoughts?

 

[bholder]

That's pretty cool. Only comment I've come up with: the indentation on the top of the saddles (barrel bolt) will likely need to be deepened, widened, and shaped to the string.

 

[shai-ga]

Yeah the sketch is not the best - the string is going through a drilled hole in the barrel, no saddle solution in this system yet
Maybe 4 more barrels, tightened from beneath, and a top flat screw held on top, and the whole thing on 1" rails, for intonation.

Or another nut on each screw, with 6 slots, on every facade.
Then you can just move it along the screw to intonate, in 6th of a turn, depends on the screw type in terms of forward movement.

 

[Scoops]

Just for reference:

Single String Headless Tuner Design

 

[Jon Clegg]

You may find that drilling that barrel nut to capture a ball end to be difficult. If I were to try this, I'd machine the part out of aluminum using a drill press.

 

[dwizum]

It's almost like putting two bass bridges on, using the first just for the saddles and securing the strings to the saddles of the second bridge for tuning.

I bet the potential for failure comes in the threads between the tuning screw and that barrel that holds the ball end. Or the barrel itself. There's going to be a lot of tension on some pretty small threads right next to the hole for the string. And I'm wondering about how important it will be to keep the tension in line with the screw so it isn't pulled out of alignment. Setting the tuning mechanism into the body on an angle to allow you to keep the screw in line with the saddle would probably help.

 

[Jisch]

I would look for a finer pitch thread on the tuner, I think that would make it easier to tune. The headless tuners I have all have very fine pitch threads, of course they're using a knob, so there is less leverage than you will get with a hex key.

 

[Matt Liebenau]

Definitely has possibilities. Fine pitch threads on the tuning bolts probably aren’t a bad idea. Most of those systems end up with some kind of flat plate as a cover over that rear tuning part. On the Steinbergers it was part of what held the string ball in the jaw but also, with out it, those tuners and screws will tend to pull up and out from the angle plate they’re supposed to be on.

I’m guessing you’re setting it up to tune with a hex key? I suppose get a dozen or so of the correct size key so you have one everywhere when you need to tune.

Keep us updated.

 

[T_Bone_TL]

...only if you count your time as "free" will this remotely compete with "$200 and up" by the time you are done with it. Which can be fine, many folks do count their time as free, doing this as a hobby.

Looking at what you've shown so far, it's already complex, and you haven't even gotten to half the problems yet, such as the uplift and potential to rattle when you DO get a bridge involved. On the adjustable bridge that this borrows most heavily from, the break angle on the strings holds the barrels down. Here, the strings will tend to pull them up, as far as I can see.

 

[shai-ga]

More about making it work with cheap standard and available parts, no CNC, no CAD work or real mechanical design, but still with a professional look and function.
I guess I will have to discover the breaking angles and pressure levels in real time experimenting.

 

[Beej]

Dave Higham came up with an elegant unit in this thread: 5-String Fanned Hybrid Headless Mind you, it's not an uncomplicated design. Just some food for thought.

I'm always interested in these as I'd love to have a simple, elegant solution to headless that I can make myself. Part of my issue is how far most systems place the bridge away from the end of the body. It affects the ergonomics I'm after.

 

[T_Bone_TL]

Just putting this on the non-head end was doing well until you got to wanting it to look "professional."

Frankenbass Budget Buster....Tuning Machines??

 

[MPU]

You need only about 12mm or 1/2" movement for tuning. I think Schack has a very simple and pretty easy to make tuner system. You need brass plate for bottom an top and brass flat bar for the string clamps. You can make the clamps 18mm wide so no need for spacer parts between each clamp. M3 bolts, top knobs from stacked pot knobs (16mm diameter) and that's quite about all parts needed. Hacksaw, flat files and accurate filing, drill press and thread tap is all the tools needed.

 

[Jisch]

I am looking forward to seeing this as it progresses.

Incidentally the Nova headless system is about $150 and it includes the headpiece for string retention. I have found it to be really well built (not trying to dissuade you, just putting it out there).

 

[MultiScaleMale]

Just don't forget your Allen wrench or you can't tune.

 

[sublimate]

I don't think you need the lock nuts or the springs - the string tension will take care of keeping it in the right place.

I think your biggest issue will be with the barrel trying to turn with nothing holding it down.

 

[dwizum]

If your true goal is simple DIY without a lot of fancy design or metalwork then why not use a tune-o-matic style bridge, and route the strings back to standard tuners along the tail of the instrument? You could recess the tuners on the back so they were hidden/protected and mounted at the right angle to get straight pull and good break angle.

 

[Arie X]

imo, i don't think anybody is gonna want to tune with an allen wrench.

as far as thread pitch goes, M4 might be ok. you really don't gain much stepping down from an M4 (.7 pitch) to an M3 (.5 pitch) or to an M2 (.45 pitch) -you just loose strength and decrease socket size and increase user frustration.

 

[Kickass]

My Washburn Force 42 tail piece has metal cubes inside, each with a threaded hole and a string retaining hole and slot, and uses big knobs on the end to tune with. The other end has holes in the neck end plate for the strings and 2 bars that clamp the strings down. Good luck.

 

[T_Bone_TL]

imo, i don't think anybody is gonna want to tune with an allen wrench.

Not THAT much of a pain, IMHO - provide hole with some strategic rubber bits or o-rings for retention and you can slot the Allen (Torx, Robertson, etc) wrench right into the instrument, or even a few if you feel the need for spares - or, as I mentioned on the janky version, consider using a drum key, particularly if you find that you normally better have one to keep your drummer productive anyway.