Rhino File Preparation

The main thing to do is separate your line work based on the type of cut you would like. The specific power-parameters and order of the cuts are handled later.

Cut Layers:

Red Layer = External Cut

Magenta Layer = Internal Cut

Scoring Layers:

Marks the surface but doesn't cut through, line is always the width of the laser

Dark Blue = Dark Score

Light Blue (Cyan) = Light Score

Engrave/Raster Layer:

This needs to be a shape rather than a line, fill the shape with a black 'Hatch'

Black Hatch = Engrave area

Printing from Rhino

In order to start laser cutting, your Rhino file needs to be sent to the machine's software 'Job Control'. To do this:

1. File > Print (or CTRL+P)
2. Check the preview window in the print pop-up...does everything look right?
3. Check the output scale, it should be set to 1:1
4. Once everything looks correct, pres 'Print'
5. Follow the instructions on the machine for how to navigate Job Control.

Tips & Tricks

• Having your lines joined instead of having lots of little line segments (especially with curved shapes) will make you job much quicker. In Rhino: Select all the lines you wish to join > Use the 'Join' command.
• Sneaky, hidden duplicate lines can cause mischief...you might not even know they are there! With nothing selected, type 'SelDup' into the command bar. Any duplicate lines will be highlighted and can then be deleted.

FDM 3D Printers

FDM or fused deposition modeling, is a material extrusion method of additive manufacturing where plastic filament is pushed through a heated nozzle, which melts the material and deposits it in 2D layers on the build platform. While still warm, these layers fuse with each other to eventually create a three-dimensional part.

SLA 3D Printers

Stereolithography (SLA) belongs to a family of additive manufacturing technologies known as vat photopolymerization, commonly known as resin 3D printing. These machines are all built around the same principle, using a light source—a laser or projector—to cure liquid resin into hardened plastic.

Additive Design for Ultimaker Printers

Evaluating your design for printability

Reducing Support Material

Supports structures are undesirable features that increase print time and produce plastic waste. Additionally, they have the potential to ruin the surfaces of prints, leading to more post-processing time.

In the end, it’s not always possible to completely avoid support structures, but we can try to minimize them as much as possible.

As a first rule of thumb, we should always consider model orientation when designing parts – that is, how parts will be positioned during printing. This should, among other things, try to eliminate overhangs and bridges, or at least reduce them to a minimum.

Secondly, think about how splitting your model could help reduce the need for supports. In the above instance, could the wheels of the car be printed separately and joined again after?

Bed Adhesion

Bed adhesion is one of the major sources of failure in 3D prints, and printing this model could prove to be a headache. When 3D prints don’t stay in place on the build plate, you can get curled, shifted, potentially disastrous results.

The amount of surface area contacting the bed is a very important factor in its ability to stick. Think of ways in which you could increase the surface of your model that is touching the bed, could you create a little flat surface on the bottom of a curved part?

Reducing Material

Another good tactic for reducing build time and filament wastage is removing unnecessary material from models. For functional parts, this can be more complex due to the direct impact of that material on the overall resistance of parts. For more aesthetic models, however, there’s less to worry about.

Chamfers and fillets are great tools for removing material while at the same time smoothing sharp corners and edges. Yet, there are other ways, too.

For the above example, we could save some filament by removing material from the vehicle’s underside. This region should stay hidden most of the time, anyway. How could you reduce material in your models?

Details, Details, Details

Small-sized features are not always able to be printed successfully. As a general rule we usually suggest features no smaller than 2mm. While this kind of issue is often detected during the model slicing, it’s good to think about it while still in the design stage and not waste time going back-and-forth between CAD and slicer.

The “Measure” tool can be an excellent ally for checking the printability of fine details. Let’s take, for example, the frame of our vehicle’s windshield. This should be the finest detail of the model, and it will definitely present a problem if we scale down the entire model during slicing.

Make sure to check all the measurements of your parts before sending them to us, if it's too small, we won't be able to print it!

Bolts and Nuts

• Bolts are used to clamp things together with the use of a nut. By tightening the nut onto the bolt, you can squeeze the materials together.
• Bolts are commonly referenced using their 'M' sizing. E.g. M6, or M8.
• This stands for Metric 6mm, and indicates that thread/shaft diameter is 6mm.

Figuring out Size

• Common Bolt sizes found in the makerspace: M2.5, M3, M4, M5, M6, M8, M10, M12
• The size of the fastener is more accurately specified using the diameter, pitch and length dimensions in millimetres

Nuts

• Hex nuts have a six-sided drive surface to match hex bolts. They're a common type of nut used with bolts to secure wood and metal components.
• Nylon lock nuts have a hexagonal head with a built-in nylon ring. As you install a lock nut, the bolt threading deforms the ring, helping prevent loosening caused by slipping or vibration.
• Wing nuts are designed to allow fastening without the use of tools; the wings allow you to tighten or loosen them with a thumb and finger.
• Cap nuts have a domed shape and hexagonal driving surface. You can often install them by hand. They screw onto the exposed threads on a bolt or threaded rod to protect against injury, or for aesthetic purposes

Screws

Common screw head types found in the makerspace

• Countersunk
• Button head

Available lengths: 15mm, 25mm, 30mm, 40mm, 50mm, 55mm, 65mm

Screws require a clearance hole, and a pilot hole. Clearance is larger than the threads and pilot is smaller, so that the screw will grab into the bottom material and clamp the material together.

PVA

The Good

• Great for wood, paper, cloth or any porous materials
• Water based, easy to clean up
• Dries with elasticity, can bend rather than crack

The Bad

• Drying time varies, could be 2-4 hours, up to 24 hours
• Soaks into materials, so cannot fill gaps

Epoxy

The Good

• Great for gluing different materials. E.g. metal to wood, wood to plastic.
• Can be quick drying (as little as 5 minutes)
• High strength

The Bad

• Can be slow drying (could set in a several days)
• 2 part system, resin part and hardener part, if not mixed in the correct ratio it could remain liquid indefinitely

Super Glue

The Good

• Fast Drying
• High Strength when used appropriately
• Low viscosity, can seep into cracks

The Bad

• Very good at sticking fingers together (dissolve with acetone. Yes we have some.)
• Brittle, doesn't bend - just breaks

Hot Glue

The Good

• Great for quick fixes
• Quite good for different materials. E.g. metals to wood, wood to plastic.

The Bad

• Hot glue guns takes time to heat up
• Please don't use it to hold your entire project together

Internal Plywood (No visible glue line)

Uses:

Laser Cutting + general woodworking

Source:

Shop or offcut bins in Kirby or Squarehouse (DFL)

Bunnings (Must be Interior Ply)

Sustainability:

Not great...

External Plywood (Visible black glue line)

Uses:

General woodworking

Source:

Bunnings

Sustainability:

Not great...

Recycled Timber

Uses:

General woodworking

Source:

Wherever you can find it (Make sure to remove all nails and screws!)

Sustainability:

Better...Good to give things a second life!

Acrylic

Uses:

Laser Cutting (best), drilling, bandsawing, sanding, melting

Source:

Shop or offcut bins in Kirby or Squarehouse (DFL)

Art supply stores (Kadmium)

Sustainability:

Average...but we can recycle it! Make sure to add it to our dedicated acrylic recycling bins

Recycled Plastic

Uses:

Great for use with the woodworking tools

Source:

Recycling bins (make sure you know what type of plastic it is)

Melt it at home (SAFELY...) or chat to Staff at the DFL

Sustainability:

Great...we love giving things a second chance

PVC Pipe

Uses:

Light-weight frames and submarines. Cut using specific cutter, ask a staff member, we have plenty.

Source:

Bunnings

Sustainability:

Terrible...definitely contributing to the end of the world

Aluminium

Uses:

Easy to work with, can be folded, drilled and cut

Source:

Have a look in the Kirby offcut storage

Sustainability:

Pretty good, just don't chuck it in the general waste bin please

Steel

Uses:

Very difficult to work with...avoid if possible

Source:

Steel suppliers

Sustainability:

Actually not too bad if you do the right thing with it

Cardboard

Uses:

So easy to work with, great for fast prototyping! Can be cut by hand, in a laser cutter or on the bandsaws.

Source:

Too many places to list, try a recycling bin to start with!

Sustainability:

Excellent

Worm Gear - High torque, Speed reduction

The Good:

• Simple
• Best for high torque, low rpm
• Can be used for gear reductions
• Can't be back driven
• Some are self locking

The Bad:

• Less gear ratio options
• Not very efficient

Planetary Gear - Flexible & Compact

The Good:

• Lots of gear ratio options
• Can be back driven
• Multi purposed

The Bad:

• Complex to build - lots of parts!
• Not very efficient

Rack & Pinion - Rotation to Linear Movement

The Good:

• Rigid
• Quite easily laser-cuttable!
• Rotational movement to linear movement
• No limit on travel length (given infinitely long rack (the straight bit))

The Bad:

• Incorrect spacing in teeth may cause backlash and unwanted slack
• Works best with higher friction but.
• Could wear out easily

• 3-12V
• 150rpm
• 1:48 in built gearbox

• 6-12V
• 5-1000rpm (depends on gearbox, check before buying!)
• Gearbox comes with the motor, there are different types, that can't be changed.

• 12-24V
• 12000-15000rpm
• Requires separate gearbox to work well.
• Planetary gearboxes can be found, from 1:3 to 1:1000

1404

• 3-4s (11.1-14.4V)
• ~4500KV
• Normally used for light drones

2212

• 2-4s (7.4-14.4V)
• ~1000KV
• Normally used for RC planes

8108

• 6-12s (22.2-44.4V)
• ~100KV
• High torque, could be used for robot arms

9G Blue Servo

Typically used for aeroplanes and low load applications. Not suited for any application where a significant load is required to be lifted.

• Plastic Gears
• 1.6kg.cm torque
• Fixed angle 0-180 Degrees
• 3-5

MG996R Metal Gear Servo

Useful for small scale robotic projects which require a heavier item to be lifted.

• Metal Gears
• 10kg.cm torque
• Fixed angle 0-180 Degrees
• 4-9V
• Can be purchased as fixed angle or continuous

Small Reduction Stepper Motor

• 5-12v
• 16-64 steps per rotation
• 2.5kg.cm
• Built in gearbox

Nema 17 Stepper Motor

• 12v
• 200-300 steps per rotation
• 4.3 kg·cm

Ultrasonic Sensors

Uses ultrasonic sound waves, sends a pulse, and receives the echo. Calculates distance from the time delay. Great at sensing things at medium range.

The Good: Can sense all material types, even see through objects,

The Bad: Struggles with thin, curved or soft objects that absorb/deflect ultrasonic waves.

Infrared Sensors

Content for this module in the infrared range (wavelength between 760nm to 1mm) to transmit data or find ranges. Infrared radiation is transmitted and bounces off objects before being picked up by the receiver.

Can also be used as a means of sending data.

The Good: Line of sight, no reliance on visible light, good for objects between 10mm to 800mm

The Bad: Ineffective at longer ranges, low data transmission rate, affected by particles such as dust or smoke.

Lidar

Rather than Radar (Radio Detection And Ranging), we have Lidar (Light Detection And Ranging)

Send pulses of lasers and measures their echoes reflecting back from objects similar to ultrasonic sensors.

The Good: Not light dependent, better at detecting smaller objects compared to Radar, smaller beam spread than Ultrasonic.

The Bad: Expensive, doesn’t register see-through materials (lights passes through transparent obstacles!)

Accelerometers

Sensor for measuring linear force/acceleration.

Most accelerometers will give you three axes of measurement

The Good: Measuring acceleration and deceleration, typically gives X,Y,Z axis readouts.

The Bad: Gives you acceleration, NOT velocity. Tells you if you're speeding up or slowing down but not how fast you're going.

Gyroscopes

Sensor for measuring angular rotation

Gives three axes of rotation, pitch, roll, yaw.

The Good: Measuring angular velocity (not acceleration, although you can calculate acceleration yourself)

The Bad: only provides angular velocity, not acceleration nor linear velocity.

Inertial Measurement Unit (IMU)

Consists of Gyroscope and Accelerometers (and sometimes, magnetometers)

Best of both worlds!

Cameras

Uses a camera and computer vision algorithms as a sensor to find objects. Everyone's got a camera (sometimes a few now) on their phone so we're not going to explain that here..

The Good: Able to identify colours and signs using computer vision to identify obstacles

The Bad: No range sensing, doesn’t work as well in low light, expensive in price and computing power.

Others

There are an assortment of other sensors that are compatible with Arduinos or Raspberry Pi's. We can't cover them all here, but if you look up the manual from the suppliers, they will show you how to use them - sometimes with example code!

Some examples are:

• Temperature
• Moisture
• Sound (Microphones)
• Ambient Humidity
• Hall Effect
• Light (Photoresistors)
• Pressure
• and many more!

Where to Buy?

If you need something quick - we suggest going to Jaycar as they have in-person stores.

The closest ones are:

Jaycar Sydney City
Jaycar Alexandria
Jaycar Queens Park

Otherwise Core Electronics and RS Components do quick shopping for their online stores!

In a pinch, Amazon next day delivery is also quite good!

Crimps

Crimps are mechanical connections that get squeezed or crimped onto the ends of stripped electrical cables to ensure a strong connection.

There are many shapes and sizes of crimps, the colour of the plastic (usually red, blue and yellow) are for different gauge of wires.

When using crimps, you should use a crimping tool, and ensure that the crimps are secured tightly, but not overly tight.

Connectors & Terminals

Connectors and terminal blocks are another great way of connecting wires. Terminal block are typically used soldered onto PCB's to provide a stronger connection (it's screwed in to compress the wire!)

There are also various different connectors like WAGO connectors that are a little more expensive, but are great at connecting wires quickly. It even works with different gauge of wires using the same connector!

Last but not least, we have a T-splice connector, which are usually used to split a single connection into two!

Soldering

Seen as one of the strongest connections, but also the hardest one to do well! There is an art to soldering, and if you're interested, we run an induction for teaching basic soldering here!

Soldering is the process of joining metal parts by melting a metal alloy (solder) to bond them together.