Light up staff, looking for help


(Tabitha Hastie) #1

Hi, I’m looking for some help on what components to buy to make this:

I can make the casing easily enough, I’m just not sure how to do the movement. I’m making a steampunk version of it so it won’t look exactly the same, but I’d like the lights and movement to be the same. The requirements are:

  1. Needs to light up at the top, orange for clockwise, blue for counterclockwise.
  2. Needs to be able to rotate indefinitely in each direction.
  3. The sticks need to sit against the base when it’s not moving, then move out when it rotates (they also move out a different amount for each direction, they come out further for anticlockwise than clockwise, but I’m not too fussed if they come out the same amount for each direction).
  4. It needs to be turned on and off by a switch, or switches, on the outside.

I’m hoping to come to the electronics night next week to start on this, but I’m not sure what components I need to bring for this (other than LEDs, I know that much!), or what would be provided at the space. I spoke to @joeatkin2 about this yesterday (I really hope I’ve tagged the right person there, I’m terrible at remembering names…), he said to use a slip ring and various other bits, but I’ll definitely buy the wrong thing if I try to go from memory, so I figured I’d better ask!

Thanks for any help!!


Costume with moving staff & wings
(Tom Newsom) #2

I’ve just had a quick doodle here and I think I’ve come up with an entirely mechanical method of doing this. You’d just have to turn the motor CW or ACW and you’d get the appropriate light and motion (including the differing extension of the arms for each direction)

Give me a bit to draw something more legible and see what you think :slight_smile:

(and yes you’ll definitely need a slip ring)

EDIT: Actually, it’s very easy to have a single switch to control motor and lighting circuits, so no need for any mechanical complexity at the motor end.

The articulating end, however, I think can be done with a pair of concentric cams. I’m having great difficulty drawing this :D, but I think it could be extraordinarily easy to make on the laser cutter with the axial attachment


(Tom Newsom) #3

Ok, just say “OMG Stop stop!” if you think this sounds crazy…

The mechanism has 4 concentric parts. I’m thinking perspex tube 5mm thick with 80,70,60 and 50mm diameters.

  • The central part D has 3 vertical slots cut in it. This is to keep all the sticks lined up.
  • The most important part C is shaped like a cup and is attached directly to the axle of the motor (I know nothing about what motor you should use)
  • The middle parts B1 and B2 are rings that are free to rotate, and slide up and down the length of C
  • The outer part A is stationary along with the handle of the staff. It sits like a bowl at the bottom of it all. It has 3 indents that line up with the “stowed” position of the arms.
  • The motor shaft runs all the way up the centre.
  • Three sets of three-way arms run out through holes in C and B1+2. A nylong bushing around the arm allows it slide smoothly in the slots
  • All three arms are free to rotate independently of the axle.
  • Each arm terminates in a hinge point. The linkage for the sticks attaches to these hinges.

The central part C is where the magic happens. It has slots cut into it that look like this.

Remember, only this part is attached to the motor.

At rest, the indent in A keeps the arms stationary.
When the motor turns, the slots move along the bushings until they reach the sloped part of the slot, at which point, the bushing, arm and connecting rings B1 or B2 are pushed up C by the sloping slot. The last to move is B2 because the sloped part is right at the end. It lifts out of the indent in A and now the whole thing is turning as the bushings are at the end of the slots.
The top slot for B1 goes to different heights depending on which way it turns, so you can get your two different stick heights. (the sticks will retract when reversing though, which might be a problem)

This drawing is not so good and is missing part D, but it shows how the linkage attaches and makes the arm go up and down. Some experimenting with lever lengths is needed, but my Lego experience tells me you can convert any linear motion into pretty much any other any other linear motion with a linkage like this.


As for fabrication, I think the cylindrical parts are all easily done on the laser cutter with the rotary adapter.

The 3-way arms can be very simply made out of aluminium and threaded rod - just cut a hexagon, or whatever, and tap 3 holes in the sides.

The linkages and hinges could be more aluminium. Not quite so sure about that.


The alternative is a retract/extend motor in each stick and a bunch of wires and a microcontroller to make everything move in sequence, but I happen to like mechanical gizmos :smiley:


(Tom Newsom) #4

I am now teaching myself Fusion 360 to see if I can mock this up and make it move…


(Tabitha Hastie) #5

@tomnewsom Oh wow, I can’t believe how much effort you’ve put into this! Thank you!!

…I’m going to admit now that I don’t understand most of it haha, this is way beyond anything I could ever design or make. If you (or anyone else) are willing to help me with this at the space, I’ll pay for your time!

Also with regards to mechanical vs electrical, personally I also prefer mechanical for this. Not for any practical reason as such, just because this is meant to look steampunk and something steampunk would be all mechanical, and having all the moving bits actually be moving to make it work rather than being artificially put on there afterwards to make it look mechanical just feels so much cooler.


(Louis) #6

I have access to fusion 360, please let me know how easy you find it to use/learn…


(Tabitha Hastie) #7

@tomnewsom I’ve read it through a few more times, I think I’m starting to understand it! I’m going to start buying stuff, so far I’ve got yellow & blue LEDs, a motor, 9v battery connector and perspex tubes (though they didn’t have 80mm so I’ve gone for 70, 60, 50 and 40mm instead). What other bits would I need? I’ve been told there’s wire available at the space, not sure what else is available there that I could use for this.


(Tom Newsom) #8

Ok, good luck with this! My time in the space is pretty limited, but will try and make it down at some point to help with the laser cutting bits. You will need:

  • Some aluminium to make the arm hubs and pivots (there’s loads of metal in the metalwork area but I don’t know whose it is). Should all be doable on the bandsaw, drill press and thread taps.

  • Some threaded steel rod for the arms, and some acrylic bushings to fit. Say M6 for the thread and 8mm outer diamter for the bushing? Let me

  • Some silicone lubricant (unadulterated - some types have extra solvents etc)

  • Some flat perspex to make the base of the “cup” that is part C (and probably on D as well. And on the top ends of both, come to think of it). Loads of offcuts in teh space, so no worries there :slight_smile:

  • An axle to run up the centre.

What’s the deadline btw?


(Tabitha Hastie) #9

Thank you! I can’t wait to get started :smiley: The deadline technically is end of May, but I’ve also got to make the outfit and these wings to go with it:

So will need to get the staff done quick enough to leave time to do those. I shouldn’t need to much help with any of that though, just the staff I wasn’t sure about!


(Stefano Romano) #10

Hi Tabitha
What you want to do is SUPER interesting, can I get involved? :slight_smile:
I never did something like that but I have few skills, an open mind and I LOVE a challenge lick that! :slight_smile:
Keep us updated when you will be at the space so we can have a chat all together!
Plus I suggest that you wait before to buy stuf… the space is full like an egg of stuff that you can have and use… scrap metal, scrap plastic, electronic components, motors, screws and more random bit and bobs that you can imagine…
I find really fun and relaxing going through all the boxes of odd stuff , a lot of ideas can spring from that!


(Tabitha Hastie) #11

I’d love for you to get involved! Yay! I’ll be in the space for the electronics evening this Thursday, if you’re around I can be there from about 6.30pm, though I’m also free tonight if you’re not available on Thursday.

I’ve bought some of the stuff already, I didn’t want to turn up at the space empty-handed and just expect everything to be provided for me! I know I’ll still need a lot more bits though, so good to hear I might be able to find some stuff there :smiley: