Re: [CAD_CAM_EDM_DRO] plastics

All plastics emit toxic fumes, at all times, it's just a question of how much,
and temperature is a major factor.

Bill

On Sat Jan 12 14:01:46 2002, Craig Chamberlin, <ccc@...> wrote:

>Ian,
>
>Our local plastic supplier only recommends cast acrylic for machining
>because of the lack of stresses.
>
>It may be possible to stress relieve the plastic by warming it to some
>temperature in an oven...BUT...I have been told that many plastics can
>emit rather noxious and often toxic fumes as they are heated up...So
>sticking with cast acrylic may be the best solution.
>
>FWIW,
>
>Craig
>
>Ian Wright wrote:
>>
>> Forgive me for raising a question which is not specifically related to CAD
>> or CAM but I have a problem which is perplexing me and preventing me from
>> finishing my mill !! ;o)
>>
>> I have been making a new mouthpiece for my euphonium out of acrylic
>> (perspex, lucite?) and I have turned it from a solid 2" diameter rod. When I
>> finished it and polished it it looked the bees knees and I was delighted
>> but, since I have been playing on it for a few days, it has developed a
>> network of fine cracks around the narrowest portion of the bore. I am
>> assuming that these must be due to vibration from the sweet musical notes
>> but, since such plastic mouthpieces are made and sold commercially in the
>> US, I assume that they shouldn't be there and are probably due to stresses
>> already in the plastic.
>> Does anyone know if there is a way to stress relieve plastics after
>> machining?
>>
>> Ian
>> --
>> Ian W. Wright
>> Sheffield UK
>> www.iw63.freeserve.co.uk

--
----------------------------------------------------------------------------
RKBA! ***** Blessings On Thee, Oh Israel! ***** 4-19!
----------------+----------+--------------------------+---------------------
An _EFFECTIVE_ | Insured | All matter is vibration. | Let he who hath no
weapon in every | by COLT; | -- Max Plank | weapon sell his
hand = Freedom | DIAL | In the beginning was the | garment and buy a
on every side! | 1911-A1. | word. -- The Bible | sword.--Jesus Christ
----------------+----------+--------------------------+---------------------

Constitutional Government is dead, LONG LIVE THE CONSTITUTION!!!!!

----------------------------------------------------------------------------