Force Induced Sabre Torch
Introduction: Force Induced Sabre Torch
There are many type of force and in this particular case we will be making use of the magnetically induce force to create a torch sabre from a STEM perspective.
This Instructable will describe the process of making a magnetic induction LED hand sabre torch primarily made from poly pipe. The simplicity of the design meaning that assembly is push fit requiring no screws or glue, no primary cells are required reducing the cost of ownership as power is generated by movement.
Feel the force and no batteries required.
Supplies
MATERIALS
22mm diameter poly pipe - 237mm
22mm diameter poly pipe straight coupling - Qty 2
18mm diameter disc or cylinder (N35), Neodymium magnets - Qty 3 - 5
* Before using magnets please read the following safety precautions from one supplier - no affiliation *
34 SWG/31 AWG, Enamelled copper wire - 176 metres
Bumpers 5mm thick High density foam or Polystyrene
21 mm insulating (none magnetic), washers (I.e. tap washers with or without holes)
Masking tape or clear tape
White LED
Supercapacitor 1F/2V7
IN5817 Schottky diode - Qty 4
10k resistor
ZTX450 NPN transistors or equivalent (I.e. 134
2N2222A)
Stripboard
Push button switch, Single pole Single Throw (SPST), momentary
Epoxy Resin polish
Ferrite Ring
* Alternative sources and part equivalents may be used based on your requirements and preferred suppliers *
TOOLS
Mitre Block
Saw
Ruler/Tape Measure
Marker
Sanding paper
Craft knife
Cutters
Soldering Iron + Solder
Pliers
Step 1: Physical Design
The physical design needs to be such that the torch can be easily held in your hand with sufficient length to allow the magnet to travel up and down the inside of the tube and a visible extension to fit the electronics and the light rod.
The torch is constructed in three main sections from 22mm poly pipe.
The generator is made up of a 135mm length of pipe.
This contains the magnets with bumpers and stoppers at each end, containing it within the tube whilst creating a soft impact at each end to prevent damage and dull the sound when shaking. Around the outside are wound the coils.
The convertor is made up of a 100mm length of pipe.
This contains the electronics mounted on strip board which will be used both to store the energy generated and drive the LED.
The light pipe being made of epoxy resin, coloured or clear in various suitable lengths as required.
Force_Powered_Torch_Sabre physical design can be found on TinkerCad
The individual elements are shown full scale and the fully assembled unit is shown at 50% of full scale to fit on the same workspace.
Step 2: Generator Construction
Cut a 135mm length of pipe with a suitable saw (hand saw and mitre block or circular saw).
Smooth the edges at both ends with sandpaper to remove any burrs.
Sand the outer edge at both ends to a rounded profile, this will make inserting in to the straight coupler easier.
Cut two 21mm diameter bumpers 5mm thick from silicone sheet, high density foam or polystyrene, optionally use 2 tap washers.
If cutting the bumpers use a small length of 22mm pipe as a template press this over the material to be cut and insert a marker or sharp blade into the inner circumference of the pipe and mark or cut the material.
The bumpers will be inserted in to the 135mm pipe one at each end.
Cut two 21mm diameter blanking plates ~1mm thick from aluminium, PCB board or nylon washers.
If cutting the blanking plate use a small length of 22mm pipe as a template press this over the material to be cut and insert a marker into the inner circumference of the pipe and mark the material. Then cut with a saw to shape and file the edges smooth.
The blanking plates will be inserted in to one end of each of the straight couplers.
The magnet will be inserted into the 135mm pipe and should be able to freely slide up and down the tube with ease.
In this case 6 * (18mm diameter x 3mm thick) neodymium magnets are stacked together, attracting faces together. Stacking magnets together with increase the field intensity however there is a "law of diminishing returns".
Optimum Stack = Diameter/Thickness (18mm/3mm) = 6
Meaning that beyond this the field strength does not keep increasing at the same rate and further additions to the length will provide small increases in performance.
A single 18mm x 18mm magnet could be substituted. 858