Manipulating and Joining Flashcards
What is Chinagraph pencil used for and what evaluate it?
It is used for MARKING OUT as it can be wiped off easily, however sometimes it can be too thick to follow.
What is a disadvantage of using a non-permanent marker?
It can be smudged easily
When is permanent marker used?
When progress is more important than high-quality finish. So good for early models
There is 0.5 HIPS sheet, what method can be used to cut it. Explain why
A scissor because it is suitable to cut fast for thin sheets
Describe the process of cutting with a craft knife.
Used to cut thicker sheets.
First SCORE along a line
Then FLEX the material until it SNAPS
When do we use Scroll-saws and what do we have to make sure whilst using it and why.
Scroll saw used to cut curved shapes
We must make sure to leave protective layer on as…
the cut may re-seal due to plastic dust heat up.
Coping Saw used where?
To cut CURVES in THIN sheets
Junior hacksaw used to cut…
fill in the blanks
sections
Why might someone use band saw?
To cut precise, SHALLOW curves and larger lines
Explain laser cutter usages
It is used to cut and engrave in 2D acrylic sheets. Hence used for decorative pieces.
Limitation of laser cutter
The size of the sheet.
Usage of milling machines.
to cut slots and grooves in blocks of suitable polymer
What can be used to cut more complex shapes?
CNC milling machines
central lathes usage
To make round components
What is CNC Lathe used for?
To cut more complex shapes
What is the difference between milling and multi-axis milling?
> > Milling machines move on 3 axes but multi-axis milling machine move son 4 axis.
A bit like lathe that could stop partway to let milling machine cut some slot.
Why is it important to have the correct drill bit?
So the polymer doesn’t whip or crack.
Larger the hole, slower the speed of drill, explain why?
The high speed can melt the plastic.
A person wants to bend a line on an acrylic sheet, describe how they would do it?
They would use a LINE BENDING.
1) They would use a STRIP HEATER to heat a material over a heated line.
2) Then use a JIG or a FORMER to bend the sheet to the desirable angle until it cools.
When is Drape forming used and how
Used when a LARGE CURVE needed
1) Sheet HEATED IN OVEN to ensure the sheet is evenly heated
2)One softened, DRAPED over a FORMER and pulled tightly by a piece of cloth until cooled.
Explain the components of press moulding and how it is done
Yoke is the upper piece and plug is the bottom piece.
1) HEAT the sheet in OVEN. to ensure the sheet is heated evenly.
2) Position over plug and pushed downwards by the yoke and clamped together until sheet cooled.
Vacuum forming and how it is done?
1)Sheet clamped to form air-tight sheet above the air chamber and mould.
2) Once heated the mould is raised and air evacuated by air pump. so air pressure forces the sheet to shape itself along the mould.
Explain why the mould’s and plug has to tapered or have draft angle, and rounded edges?
So it can be removed easily
How to make recesses in vacuum forming?
Use vent holes to allow air pressure press the heated plastic into the holes.
