3D Printed Bass with Aluminum Backbone

[GisserD]

Pickups ordered today. 

Changed my mind and went for a nordstrand jazz and mm combo. Not blades as previously intended. 

Design has been progressing, I'll publish some more ideas soon. 

[GisserD]

Babicz Bridge and Nordstrand 3B-5B Preamp now aquired.

[mixingwithtom]

This sounds interesting, hope it’s going well! Wondering which CAD programme you are using?

[GisserD]

4 hours ago, wwcringe said:

This sounds interesting, hope it’s going well! Wondering which CAD programme you are using?

Siemens NX

[mixingwithtom]

I’m not familiar with it, but cool! Best of luck & can’t wait to see more

[GisserD]

NEW BODY SHAPE!

the idea was to give more access to the upper frets and make the lower horn more synpathetic to the shape of the upper horn which i like.

(old one for comparison in lilac)

Edited January 14, 2020 by GisserD

[GisserD]

[GisserD]

Parts starting to arrive now

(Nordstrand 3band pre in the box)

[GisserD]

some developments today in the moving pickup design...

 

2x Multi start screw with thumb wheel at each end to move pickup shuttle. 1 revolituon wil be 8mm travel.

im considering moving the entire mechanism to be actuated from the back of the bass for better acces, however it then opens up the opsibility of it moving unintentionally.

[SpondonBassed]

What sort of linear bearings will the shuttle run on?  I'm assuming plain from your diagram.

[GisserD]

Bearing? 

There are no loads involved so I think bearings are unnecessary.

The shuttle actuates through a T slot in the front body panel. To stop it falling out but even that isn't strictly necessary.

What isn't shown in those pics is a housing on the back of the shuttle that will encapsulate the nut that runs on the screw.

 

[GisserD]

Got home. Had a glass of wine and upon reflection, I now think this pickup actuation design is overengineered.

There is a far simpler solution. And it takes up less space. And it's cheaper. No vibrations,  allows more movement. And quicker to move the pickup. 

A simple recessed thumb screw through the body, securing the shuttle from the back. 

 

 

Edited January 15, 2020 by GisserD

[SpondonBassed]

19 minutes ago, GisserD said:

There are no loads involved so I think bearings are unnecessary.

Then what finish will be on the surface that the shuttle slides upon?

I'm just thinking that a single screw thread might allow the shuttle to bind with some finishes if it is even slightly out of alignment with its guide channel.  Twin screw threads would help but they would also ruin a simple and effective idea because they'd have to be connected so as to turn in unison. 

[SpondonBassed]

5 minutes ago, GisserD said:

A simple recessed thumb screw through the body, securing the shuttle from the back. 

I like that a lot better.  Simple = reliable and easy to fix if things go wrong.

[MoonBassAlpha]

How about securing plastic shuttles with magnets? As you might imagine, it's easier to slide magnets across the surface they're stuck to than pull away perpendicular to the surface.

[GisserD]

Nice idea. But I'd need some pretty strong magnets on the other side of the 8mm aluminium to make that work as ally isn't magnetic. And I'm not sure how that would affect the pickups at all....

[Maude]

Could some sort of cam lever arrangement be used for locking the sliding pickup? Two rails could still be used to stop any twisting motion making the pickup snag when sliding, but only one need have the cam lock. Lift the lever to release, slide the PU and push the lever down to lock. Similar sort of thing to quick release bike spindles. 

[itu]

Cut half of the longitudal (?) thread away from the nut and the screw and you can lock the pickups with just a half turn of the screw. Like the locks in cannons.

See "stepped thread", "breech screw" etc.