Workflow video
The vacuum forming workflow
Here, we present an example FormBox workflow, from idea to final part. It is important to note that each project is unique and may require different or additional steps.
Step 1: Designing the tool
In order to give the formed plastic sheet its desired shape, you will need to use a tool. Here are some things to consider when designing your tool:
- Draft angles are essential as they make de-molding much more comfortable. The greater the draft, the easier it is to remove the formed sheet from the tool.
- Undercuts should be avoided as you won't be able to remove the object once the plastic sheet cools down. However, small undercuts and vertical walls are possible when using our Flex sheets
- Air holes should be added to non-porous 3d printed tools and handmade tools. This allows the sheet material to pick up more detail and form inside of internal voids without trapping any air.
Click here for more information on 'Tool design and creation'
Step 2: Manufacturing the tool
You can use various technologies to manufacture a tool, including 3D printing, CNC and laser cutting. Click here on more information on tooling manufacture
The Mayku FormBox also works with handmade tools made from wood, stacked card & paper, polymer clay and foodstuff such as potatoes (We’ve even been known to use digestive biscuits as coaster templates in the past)!
‘Tip’ Soft shapes that go into the FormBox can’t be too soft, or it will just squish or flatten the template when the vacuum goes on. So - if you wanted to form a banana, freeze it first.
When making a tool or using a found object, make sure it:
- Adheres to the rules of vacuum forming
- Melting temperature above 100c
- Strong enough to withstand the pressure of the vacuum
- If using a found object, try it first with a less precious piece if you can
- Create a 3d printed version if you are worried about using an original precious object
- Re-print or re-cast the object or 3d printed part if the tool melted or is not strong enough - like in this video
Step 3: Choosing the Material
The FormBox works really well with thermo-plastics (plastics that go soft when warm).
At Mayku, we have a range of materials that you can buy directly from us. The FormBox heating controls are set for the Mayku sheets;
Some of our materials, such as the Clear Sheets have a protective film, so make sure you remove this before using.
It’s also possible to use thermoforming materials provided by third parties. As long as it’s one of the tested compatible materials on our website, it’ll be fine to use.
If you are using a 3rd party material we recommend contacting the material manufacturer/seller prior to using 3rd party materials to confirm:
- What the working temperature of the material is for casting and the material heating time as this might vary between sheets. We can’t guarantee the quality of 3rd party materials but it’s always worth a try.
- If the material you are using releases harmful fumes as it melts. For example don't use PVC as it can release chlorine gas if it burns. If in doubt make sure you position the FormBox in a well ventilated area.
Step 4: Forming process
Pre-forming checklist:
- Check that there is no debris on the forming bed and seals
- Use a clean sheet and remove protective film, if present
- Ensure no debris is on the sheet
- Check quality of your tool for cracks or imperfections
- Clean your tool removing any debris
- Optional / depends on the template and design: Coat the tool with PTFE before forming, for easy de-moulding. We recommend applying 4 coats, allowing each coat to dry between applications. Wipe dry before forming
- To keep your FormBox running in optimal condition, we recommend using it in 45-minute sessions, followed by a 20 minute cooling period with the temperature dial switch to OFF. Make sure you let the fans cool the heater down for 10 minutes, before turning off at the mains
Follow these step-by-step instructions:
When setting up your FormBox for the first time, follow these easy steps for everything to work smoothly.
- Plug the vacuum into the back of the FormBox
- Plug the FormBox into the wall
- Turn the vacuum on, it will not make any noise while its on
- Turn the FormBox on
- Turn the temperature to the heat you want, depending on which sheets you're using. The Mayku sheets have temperature settings on the box
- Put your sheet on the bottom bed, pull the top tray down and lock in the handles
- Pull the trays up to the top and wait for the plastic to be ready to form
- When you pull the handles down to form over your object, the Formbox will activate the vacuum and it will start making noise while it forms
- Wait 15 seconds after you've formed your object to allow it to cool down, then remove from the bed
Tips to follow
How does the vacuum work?
Placing the tool on the bed
- If you are using a single tool, place it as centrally as possible on the forming bed
The size of the FormBox bed is 200mm x 200mm. The maximum width and length you are able to mold is 150mm x 150mm give or take, depending on tools overall dimensions. To avoid tearing the plastic, we suggest not vacuum forming anything taller than it is wide.
- If working with multiple tools - space the tools apart, at a distance greater than the height of the tallest tool.
How do I clamp the trays together?
How do I know when my sheet is ready?
Mayku clear sheets will ripple at the edges and begin to droop in the middle when they are ready to form. Mayku form sheets will soften across the whole sheet. When the corners are fully softened, it’s ready to form.
There are no hard and fast rules as to how long this should take, so experiment with different times and temperatures to find what works best for your template shape and environment. Look for when the material just starts to bow and bring both trays down over your tool.
Wait 15 seconds after you've formed your object to allow it to cool down, then remove from the bed.
Check out the video below to see what a Mayku sheet will look like when it’s ready to form.
How much pressure should I apply when lowering the trays of my FormBox?
When pulling your trays down to to the base of the FormBox, you only need to apply enough pressure to make the silicon airtight. This is roughly about as much pressure as you would use to close a tupperware lid. A quick action to remove the trays from the heater unit followed by a smoot downward motion to lay the pastic over your template will create the best forms.
Machine cooling time and turning the machine OFF
To keep your FormBox running in optimal condition, we recommend using it in 45-minute sessions, followed by a 20 minute cooling period with the temperature dial switch to “OFF”. It’s located on the right hand side of the front panel of your FormBox.
Make sure you let the fans cool the heater down for 10 minutes, before turning off at the mains.
Increase longevity of the tool
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Allow the tool to cool down slowly between forms
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Add fillets and large draft angles during the tooling design.
Demolding
- Coat the tool with PTFE before forming, for easy demolding for end parts (not suitable when casting edibles).
- You can also add a little bit of Cooking oil to your template if casting chocolate into your mold
- Demold swiftly after forming (when warm)
- Introduce air into the mold
- A bit of air pressure with an airgun to inflate through the air holes from the underside or in between the formed part and the plastic sheet will usually make your mold pop right out
- Prying up the edge of the form while applying pressure to the center
Tips for demolding chocolate
Proper tempering is key. When chocolate is tempered correctly, it will shrink in the mold, making demolding easier. Additionally, ensure your master tool is well-designed. For more details, read our article on tool design and creation.
For more information read our FormBox Trouble shooting guide
Step 5: Post-processing
Once you have removed the tool from the formed material, you can remove the excess material. For thinner and flexible materials, hand-cutting with Kevlar scissors or a scalpel will work great. If you're using thick or rigid materials, using electric tools like a bandsaw, drill, or a rotary power tool is highly recommended.
If you're using the FormBox for small batch production, consider making a jig to quickly and accurately post-process the part.
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