Re: Primary support -update


I probably have the same saw, and it will cut 1.25in Lexan if you cut slowly 
and use a carbide tipped blade as Brian stated. If the plastic looks like 
it's melting, then pull back slightly to let it cool and then continue.  
Never lift it off the table while the blade is spinning or it will catch and 
shatter. If you want to stop cutting, turn off the motor and wait for the 
blade to stop before lifting the part off because pulling back on the part 
with the blade spinning can also cause chips.

Slowing down the motor will only make make the blade stick easier.  You dont 
want a "flat" type of blade for plastic.  The less surface area on the part 
the better - the carbide tips are usually larger than the thickness of the 
disk and the carbide takes the heat the best.

If the blade gets too hot it will stick to the plastic and stall - don't 
panic - just hold on and hit the stop button. The best way to avoid this is 
to cut very slowly. 

I also take the saw outside when cutting plastic and phenolic, because of the 
toxic odors (phenolic especially). And wear a mask if you cut fiberglass with 
a table saw (I use a fan located behind me to direct the dust away).  

Thin plastic is best cut by scoring half way through with the back edge of a 
razor blade ( a dull carpet blade works great) and then setting the part on a 
pencil (at the edge of the score line on the non-scored side) and breaking it 
by pushing down on both sides. Takes practice though.

I worked in a glass and plastic shop as a kid.

Just my 2 pennies worth.


<< Original Poster: Terry Fritz <twftesla-at-uswest-dot-net>
 I have one of those small Makita table saws.  I have always been fairly
 afraid to cut anything in it but wood.  It would really be nice to use it
 for cutting plastics and such for my Tesla coil projects.  However, with
 the big direct drive brush type motor, the thing is too dangerous if
 anything hangs up.  The high-speed direct-drive high torque motor does not
 stall gracefully at all!!  It is great for wood but odd materials may go
 nuclear...  I was wondering if simply putting the variac in line with it
 (universal motor) would reduce the speed and torque to sane levels and if
 that would be of use for cutting plastics and such?  I was going to give
 this a try but thought I would check around first for tips...
 At 08:02 AM 7/23/99 -0700, you wrote:
 >HDPE can be cut into strips with almost no effort. Use a table saw with a
 >cheep (many tooth) carbide blade ($6.00 at HomeDepot). A couple shots of
 >silicone on the blade before starting also helps.
 >Brian D. Basura