"Rollo" Knobs for Altec, Langevin, and other Vintage Gear

[mjrippe]

Following up on a request in the Black Market, I am posting my drawings of the famous "Rollo" knob for free use. The knob this was derived from was on loan from Doug @emrr so big thanks to him!

@thomasdf is hoping to do the 3D model and make files available.

-Mike

 

[thomasdf]

Awesome 😍 many thanks
I’ll work on it later on tonight or this week and I’ll post here
Cheers

 

[thomasdf]

Well I had some unexpected spare time this morning so this is were I am right now :
This is a 2 grooves version, with a single set screw hole on the side. I seem to remember there are two set screws appart 90° from one another, one being through the indicator groove. I can easily add that.
I'll probably make a single groove, too.

I've kept all the edges / angles sharp, but I'd probably advise putting a little fillet to them, in order to make them a little smoother. If you have some high res pictures I can try to mimic the OG's edges.
I haven't modelled the brass insert

The TXT has to be changed to .STL in order to work

 

[ruffrecords]

How is the set screw going to work? Is there some kind of standard brass threaded insert that can be used?

Edit: Looking at the drawing in detail I see there is a brass insert. Are these readily available??

Cheers

Ian

 

[zzzzz]

Following. Looking great.

So these have a sort of circular hole? Like Ian mentioned re: set screw.

Would be great to someday have one that would fit a standard fader cap too as you mentioned

 

[thomasdf]

Give me the precise fader cap dimensions and I’ll do that, it’s quite easily done

For starters I wanted to do something true to the original. A rectangular piece of brass can be bent into a circular insert, drilled and tapped. Or maybe the original can be found ?

For my personal use I was thinking of having the screw hole drilled at 2.5mm and then tapped for m3 set screw + inside central hole at the correct size for the pot shaft. Milled in aluminium

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Edit: here are some pictures taken from two different Reverb sales

 

[zzzzz]

Give me the precise fader cap dimensions and I’ll do that, it’s quite easily done

For starters I wanted to do something true to the original. A rectangular piece of brass can be bent into a circular insert, drilled and tapped. Or maybe the original can be found ?

For my personal use I was thinking of having the screw hole drilled at 2.5mm and then tapped for m3 set screw + inside central hole at the correct size for the pot shaft. Milled in aluminium

---

Edit: here are some pictures taken from two different Reverb sales

Good stuff! Yeah I’ll get some dimensions for the faders in question in a week or two. I wish I knew how to actually do 3D CAD stuff…

 

[thomasdf]

I’ll be happy to do it for you
(I am using Fusion 360, but Google Sketchup is pretty easy to use)

 

[zzzzz]

I’ll be happy to do it for you
(I am using Fusion 360, but Google Sketchup is pretty easy to use)

I did something SUPER simple in Autodesk Tinkercad once, but that's obviously pretty limited. Will look into Sketchup!

Interested in these "rolo" caps to use in place of these totally unobtainium Auditronics numbered caps. Same vibe / will look good.

 

[Script]

Printed it.

Machine suggested to convert from inch to mm, otherwise object too small.

The 6 mm pot shaft has a layer of shrink tube. Used a standard M3 screw to thread the set screw hole (PLA / plastic is soft enough). Now need to get some flat-headed M3s.

Big thanks to @thomasdf