Tools for Working with Acrylic
by Strangetanks
Aquarticles
If you don't buy the tools you need, you will eventually pay for it,
but not have your tool.
--Henry Ford
What Henry is trying to say is that it pays to have the tools you need. Not only are
you paying for materials which may go to waste but you are also investing time. Most
importantly you are gambling with your self confidence, completing a project successfully
will give you a stepping stone to your next project. Before starting any project try to
determine what tools you are going to need and how sophisticated you want your project to
be. Because acrylic is clear, it is very unforgiving of mistakes. Your goal should be to
build things which look like you bought them, otherwise perhaps buying them is a better
option.

Router: Probably one of the most important tools you will use for
achieving professional quality results. Routers may run between $100 and $300 depending on
quality. A router, which is capable of accepting both 1/4 inch and 1/2 inch shank bits,
will be beneficial. You also want a router that can be fitted with guide collars. Another
thing to keep in mind when purchasing a router, many of the methods I will be describing
are based on mounting your router under your work table with the cutter protruding from
the surface. Look for a router, which you feel, will be easy to mount in this manner.
 
Although acrylic is softer than tool steel, it will dull regular tool steel cutters
rather quickly. When buying router bits look for the highest quality carbide tipped
cutters you can find. They will be more expensive (around $20) but will make smoother cuts
and last longer than lower quality bits.
 
(photo courtesy of Gopi at www.indianaquariumhobbyist.com)
Solvent Cement and Applicator: The adhesive used to cement acrylic actually melts
the plastic chemically, allowing the molecules from both parts to combine, forming strong,
watertight, clear joints. The method most commonly used in acrylic fabrication is referred
to as capillary cementing. The parts to be joined are held in the desired position, and a
water-like solvent cement is allowed to flow into the joint, bonding the parts together.
The product most commonly available, and I would recommend, is Weld-On #3. Thicker solvent
cements (Weld-On #16) are also available, although I do not recommend using these as they
often result in unsightly, unprofessional looking joints. Specially designed applicators
or hypdermic syringes can be used to apply the solvent.
Scrapers: Every glue joint needs to be as perfectly fitted as possible. The
smallest gaps will result in bubbles in the joint which are unsightly and weaken the
joint. This includes the texture made by sawing and machining. Scrapers can be made from
any piece of steel (preferably tool steel) which is flat and has a sharp corner. The flat
side of a hack saw blade works well, although I prefer using a cut-off cutter bit used on
metal lathes because it is stiffer. Most plastic suppliers will also carry scrapers
appropriate for acrylic. Tool marks should be carefully scraped away until the edges of
the material are smooth and square. This also creates better surfaces for flame polishing.

Scoring tool: Scoring a piece of plastic sheet actually places a heavy
scratch on the surface, creating a weakened area. Bend the piece of plastic, supporting
the material just behind the score mark and Crack! You now have 2 pieces. This method of
cutting plastic takes a little practice but is very easy to master. It works extremely
well for 1/8 inch and 1/4 inch material although the larger the piece is the greater the
pressure you need to apply. I would not recommend it for large sheets or anything over 1/4
inch thick as the break will tend to drift away from your score mark. Scoring tools are
usually sold by your local friendly plastic store and will only cost a few dollars, it is
an investment which will pay for itself in a very short time.

Blow Torch: Just a plane old propane blowtorch can be used to flame polish
edges, giving them that clear bright finish. Professionals use a hydrogen/oxygen torch,
they do work better but I've never met a hobbyist with one. I've never had any problems
flame polishing with a propane torch although colored plastics tend be more difficult.
Flame polishing requires a lot of practice to do well, buy some scrap and practice until
you are completely comfortable with holding a blow torch on your newly completed project
without creating a big mess.

Squares: Check everything for squareness then check it again. Pay the
money for a good carpenters square and combination square, they will save you twice as
much in headaches resulting from parts which fit poorly or jigs which hold parts
incorrectly.

(photo courtesy of Gopi at www.indianaquariumhobbyist.com)
Clamps: You can never have too many clamps!
Some other tools you may find useful:
Drill bits need to be purchased specifically for cutting into acrylic. The
cutting surfaces are ground at different angles and work surprisingly well. Expect to pay
between $5 and $15 per bit based on diameter. I would not even bother trying to drill a
hole in acrylic with a standard drill bit unless your completely desperate and have a
drill press.
Saber saw blades also must be purchased at your acrylic supplier. The teeth are
specially shaped to cut acrylic, and they outperform standard blades well enough that they
will be worth every penny.
Hole saws work very well in acrylic but, as with router bits, you need to buy
very high quality hole saws or you will find yourself cracking and melting plastic instead
of cutting it. Expect to pay $10 and up. I prefer the Starrett brand.
Strip heaters are used to locally heat up plastic to create nice bends. You can
purchase strip heaters from various suppliers or you can make your own. Hopefully I will
publish an article on making strip heaters in the near future.
A table saw is not a tool which is absolutely needed for working with acrylic.
Most plastic suppliers will cut sheets to size for you, and simply charge you by the
square foot. If you do happen to have one however, I have found that the carbide tipped
blades available at the hardware store perform well and don't feel there is any real need
to purchase one of the special circular saw blades available (they run about $100).
Bandsaws are very convenient to have but keep in mind that acrylic tends to dull
steel quickly. If you are melting through plastic instead of cutting, its time for a new
blade.
Editor's note: Other articles you
might find useful include:
MAKING
AN ACRYLIC AQUARIUM
ACRYLIC
AQUARIUM REPAIR
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