Belovac Vacuum Forming Machine
|Make/Model||Belovac BV E-Class|
|Host Area||Hot Metals|
This vacuum forming machine has been donated by SAIC and is currently installed in Hot Metals area. A Danger Committee was formed and the machine is ready for member use pending authorization.
Authorization for this machine is on demand. Please ask one of the authorized users (below).
This machine is working but requires maintenance and improvements.
Vacuum Forming, is a type of Thermoforming,which is the process of heating a plastic sheet and stretching it over a mold. As the plastic cools, it hardens, permanently retaining that shape.
This device can handle any thermoformable plastic up to 3/8" thick.
Depending on which platen/frame that is used, the machine can accept 3 sizes of plastic sheets. ?x?, ?x? and ?x? cm.
The "buck," or form, may be any sturdy shape that can tolerate a bit of heat. Wood, MDF, metal, and polyester resin work well. Avoid shapes with hollows underneath because they have a tendency to collapse. Shapes with undercuts, or shapes taller than they are wide, will be very difficult to remove from the formed plastic. Paint, shellac, or epoxy resin can cause the hot plastic to stick.
The oven must be used only for vacuum forming. Please do not attempt to use this machine to dry materials or anything other than its intended purpose.
Other related tools/skills:
- ShopBot Auth - to create molds out of MDF with the CNC.
- Bandsaw Auth - To cut flashing (excess material) from thick finished parts with Vertical Bandsaw.
The following instructions are an initial release of how to run the machine.
The Vacuum Former has an oven surface for heating and softening the plastic. It is made of multiple panels (total 6) infared radiant heating elements, draws a total 80,000 watts (top and bottom), and reaches full operating temperature depending on Active heating time set on the timer.
The most likely source of problems would be for someone to leave the plastic under the heater for way too long and set it on fire. To help avoid this error, we are only using the center top panel for heating. Ignoring safety protocal is cause for revoking authorization.
Fumes from most plastics are not expected to be significant when the machine is used properly (i.e., nothing is on fire). If fumes do turn out to be a concern, the machine can be retrofitted with a fume hood. Then existing exhaust duct for the Forge could be used.
- HOT SURFACE - Metal Frame holding material and handles will be hot. Wear Gloves during operation.
- FIRE - Material may catch fire while heater is left on. Do not leave unattended.
- CRUSHING - Make certain there is nothing obstructing the platform, before pulling the pneumatic lever raising the mold to frame. Clear Obsctructions.
- ELECTRIC SHOCK - High Voltage machinery (3 Phase Power) required to run motors and heating elements. Make certain cabling is secure and undamaged before operating. Check Cabling.
Company page: http://www.belovac.com/manual_deep_draw.html
Tips & tricks
How long does it take to heat the plastic sheet?
- This depends on which material and thickness is specified.
How do I know when the plastic is ready to form?
- Generally speaking it is necessary with any new material to establish the correct heating cycle. Plastic is ready to form when it becomes soft and pliable especially nearer to the clamping frame. This is known as glass transition temperature (Tg). Once you have established the time you can set the heater timer for accurate and repeated heating cycles.
Why is the plastic webbing on the mold?
- Material is too hot.
- Insufficient vacuum.
- Excess of material. Use reducing windows.
- Poor mold design.
Why can't I achieve good definition on the finished part?
- Material too cold
- Mold too cold.
- Insufficient vacuum.
- Insufficient vacuum holes in the mold
Why Is the plastic thinning over the mold when formed?
- Sheet cooled whilst forming.
- Mold design with insufficient draft angles.
- Too thin plastic gauge.
- Pre-stretch required.
- Plug assist required.
Why does the plastic bubble and pit when heated?
- Material is Hygroscopic which needs to be pre-dried prior to forming.
- Mold or plastic sheet too dusty
Why does the plastic stick to the mould when I try to release?
- Mold not fixed on baseboard.
- Insufficient draft.
- Mold undercuts.
Maintenance and Repairs
- Get Running - DONE
- Add equipment sticker to machine for wiki info
- Fix platen/frame rubber seals
- Build basic test mold for demos and training. (PS1 Logo or Mask)
- Move Gauge before valve to measure vacuum
- Larger Vacuum Tank
- More powerful Vacuum Pump
- Temperature Monitoring
- Attach Control Panel to machine
List of Currently Authorized Users
|Authorized Member||Authorized By||Date|
|Greg "Nerobro" Teiber||Andrew Camardella||1/12/19|