Characteristics of
the material:
Acrylic is half the weight of glass, impact resistant,
unaffected by sun or salt spray. It has a temperature
range of -10°C to +55°C
for continuous service. Cleaning:
Wash with mild soap or detergent, with plenty of lukewarm
water, dry with soft cloth or chamois. Grease, oil or tar
can be removed with kerosene. Solvent residue should be
removed by washing immediately. Do not use window
cleaning sprays, scouring compounds, acetone, petrol,
benzene, carbon tetrachloride or lacquer thinners.
Masking:
When working with the material, leave the paper or
plastic masking film on the sheet as long as possible.
Except for intricate detail work you should remove the
masking only when your project is completed. Never leave
the masking exposed to sunlight or water.
Working with acrylic sheet:
DO
Keep masking on as long as possible. Use metal
cutting saw blades and drills which are ground and
sharpened specifically for acrylic sheet. Make sure all
tools are sharp. Use water or drilling oil as a coolant
when cutting sheets over 3.0mm thick or drilling sheets
over 4.5mm thick. Wet the material before cleaning.
DO NOT
Use saw blades with side-set teeth. Saw teeth ideally
should be ground with 0° of rake and be of uniform
height and shape.
Cutting Acrylic Sheet with a knife or scriber:
Acrylic sheet up to 4.5 mm thick may be cut by a method
similar to that used to cut glass. Use a scribing knife,
a metal scriber, an awl, or a utility knife to score the
sheet. Draw the scriber several times (7 or 8 times for a
4.5 mm sheet) along a straight edge held firmly in place.
Then clamp the sheet or hold it rigidly under a straight
edge with the scribe mark hanging just over the edge of a
table. Apply a sharp downward pressure to break the sheet
along the scribe line. Scrape the edges to smooth any
sharp corners. This method is not recommended for long
breaks or thick material.
Cutting with power saws:
Special blades are available to cut acrylic. Otherwise
use blades designed to cut aluminium or copper. Teeth
should be fine, of the same height, evenly spaced, with
little or no set.
Table and circular saws:
Use hollow ground high speed blades with no set and at
least 5 teeth per inch. Carbide tipped blades with a
triple chip tooth will give the smoothest cuts. Set the
blade height about 3.0 mm above the height of the
material. This will reduce edge chipping. When using a
hand held circular saw, clamp the sheet to the work
surface and use a length of 25 x 75 wood to distribute
the clamping pressure and act as a guide for the saw.
Feed the work slowly and smoothly. Lubricate the blade
with soap or beeswax to minimise gumming from the masking
adhesive. Be sure the saw is up to full speed before
beginning the cut. Water cooling the blade is suggested
for thicknesses over 6 mm, especially if edge cementing
will be performed.
Jig saws:
Use metal or plastic cutting blades. The blades you use
to cut acrylic should never be used for any other
material. Cut at high speed and be sure the saw is at
full speed before beginning the cut.
Hand saws:
Good results are possible, but very difficult. Ensure the
acrylic is clamped to prevent flexing. Flexing at the cut
may cause cracking.
Routers and shapers:
Use single fluted bits for inside circle routing and
double fluted bits for edge routing. At the high speeds
at which routers operate it is critical to avoid all
vibration. Even small vibrations can cause crazing and
fractures during routing.
Drilling:
Regular twist drills can be used, but need modification to keep the
blade from grabbing and fracturing the plastic. Modify the bit by
grinding small flats onto both cutting edges, so the bit cuts with a
scraping action.
Scraping:
The first step in getting a finished edge is scraping.
The back of a hacksaw blade is perfect for scraping.
Simply draw the corner of the square edge of the blade
along the edge of the acrylic.
Filing:
A 300mm smooth cut file is recommended for filing edges
and removing tool marks. File only in one direction. Keep
the teeth flat on the surface, but let the file slide at
an angle to avoid putting grooves in the work.
Sanding:
If necessary, start with 120 grit sandpaper, used dry.
Then switch to a 220 grit paper, dry. Finish with a 400
grit wet/dry paper, used wet. Grits as fine as 600 may be
used. Always use a wooden or rubber sanding block. When
removing scratches be sure to sand an area larger than
the scratch. Sand with a circular motion, and use a light
touch and plenty of water with wet/dry papers. Almost any
commercial power sander can be used with acrylic. Use
light pressure and slower speeds.
Polishing:
Final polishing will give acrylic a high lustre.
Power-driven buffing tools are recommended without
exception. Buffing wheels are available as attachments
for electric drills. A good buffing wheel for acrylic
consists of layers of 5 mm carbonised felt, or layers of
unbleached muslin laid together to form a wheel. Solidly
stitched wheels should be avoided. The wheel should reach
a surface speed of at least 400 metres per minute. Speeds
of up to 1200 metres per minute are useful for acrylic.
Acrylic should be polished using a commercial buffing
compound of the type used for silver or brass, or you can
use a non- silicone car polish that has no cleaning
solvents in it. First, however, tallow should be applied
to the wheel as a base for the buffing compound. Just
touch the tallow stick to the spinning wheel, and then
quickly apply the buffing compound. To polish, move the
piece back and forth across the buffing wheel. Be careful
not to apply too much pressure. Keep the work constantly
moving to prevent heat build up. Never begin polishing at
the edge of the sheet. The wheel could easily catch the
top edge and throw the piece across the room or at you.
Forming Acrylic:
Acrylic can be heated to make it pliable. It will become
rigid again when it cools. Never heat acrylic in a
kitchen oven. Explosive fumes can accumulate inside the
oven, and ignite. A strip heater is the best tool to form
acrylic. This tool will only form straight line bends.
The strip heater will heat just the area to be formed.
Heat the sheet until it begins to sag at the bend line.
The bend should be made away from the side exposed to the
heating element. Sheet thicker than 4.5 mm should be
heated on both sides for a proper bend. Use forming jigs
or clamps for best results, and wear heavy cotton gloves
when handling heated acrylic. Forming other than straight
line bends will generally require specialised equipment
and jigs.
Capillary cementing Acrylic:
This is the most popular method for joining acrylic.
However, this method will not work at all unless the
parts to be joined fit together perfectly. Make sure the
parts fit properly. Then join them with masking tape or
clamp them in a form to hold them firmly in place. It is
important that the joint be in a horizontal plane, or the
cement will run out of the joint. Apply the cement
carefully along the entire joint. Apply from the inside
of a box-corner joint, and on both sides of a flat joint.
A needle-nosed applicator bottle is recommended. The thin
cement will flow into the joint through capillary action
and form a strong bond. Maximum bond strength will not be
reached for 24 to 48 hours.
Viscous cementing:
Viscous cements are used for joints that can't be
cemented with capillary cementing, either because the
joint is difficult to reach or because the parts don't
fit properly. Viscous cement is thick and will fill small
gaps. It can make strong transparent joints where solvent
can't. You can make your own viscous cement by dissolving
chips of clear acrylic sheet in a small amount of
solvent. Apply a small bead of cement to one side of the
joint, join the pieces, and tape or clamp in place until
cured.

The data sheet below describes General Purpose (GP)
cast acrylic, High Impact (HI) and Ultra High Impact
(UHI) acrylic sheet.
Properties
|
ASTM
Method
|
Unit
|
GP
|
HI
|
UHI
|
|
General |
|
|
|
|
|
| Specific
Gravity |
D 792 |
g/cm³ |
1.19 |
1.18 |
1.17 |
| Water
Absorption |
D 570 |
% @ 24 hrs |
0.3-0.4 |
0.3-0.4 |
0.3-0.4 |
| Light
Transmission |
D 1003 |
% |
92 |
91 |
90 |
| Dielectric
Strength |
D 149 |
Volts/Mil |
450-550 |
450-550 |
450-550 |
|
Mechanical |
|
|
|
|
|
| Notched
Izod Impact |
D 256 |
J/m |
22 |
50 |
64 |
| Tensile
Strength |
D 638 |
MPa |
74 |
54 |
38 |
| Flexural
Strength |
D 790 |
MPa |
112 |
84 |
60 |
| Hardness
Rockwell |
D 785 |
M or R |
M80-100 |
- |
- |
|
Thermal |
|
|
|
|
|
| Cont.
Working Temp |
|
°C |
77-86 |
76-82 |
75-80 |
| Vacforming
Temp |
|
°C |
135-190 |
135-190 |
135-190 |
| Thermal
Expansion |
D 696 |
10^5/°C |
7.7 |
9.4 |
11.3 |
These values are representative of those obtained
under standard ASTM conditions and should not be used to
design parts which function under different conditions.
For more information on available colours and tints, see the
Acrylic Colours page.
For more information on Glazing with Acrylic sheet, see our
Glazing page.
For more information on Light Transmission of acrylic sheet, see our
Light Transmission page.
Download this page as a PDF
file
Download Acrylic MSDS 
|