Artists use something called "fixative spray" to protect charcoal drawings. It might work better than hair spray.

http://www.dickblick.com/zz217/11/

Jim Hannon

---------- Original Message ----------------------------------
From: ChrisAtUpw@.......
Reply-To: psn-l@..............
Date:  Mon, 26 Sep 2005 20:43:14 EDT

>In a message dated 26/09/05, asc@............... writes:
>
>> Chris
>> No need to spray the back. Just use hair spray for oily hair - it contains 
>> no  oil particles which cause the blotchy look and can obscure the first 
>> arrival.
>
>Hi Kevin,
>
>       Thanks for the comment! The blotchy look on my early gliding barograph 
>traces came from actual blast / droplet removal of areas of carbon. The 
>coating is only lightly attached and the adhesion can be somewhat variable. Sure, 
>with practice I learnt to lightly smoke the paper just the right amount and 
>later spray the coat from a considerable distance to fix it to get a nice clear 
>trace, but this took quite a bit of trial and oops. 
>       I later found it much easier to spray / soak just the back of the 
>paper and get a 100% reliable good trace - there is no skill to learn and it uses 
>less hair spray! You can also use other types of spray lacquer. The paper also 
>becomes more translucent making the trace easier to read. Why do things the 
>hard way?
>
>       Regards,
>
>       Chris Chapman
>
>
--
Jim Hannon
http://www.fmtcs.com/web/jmhannon/
42,11.90N,91,39.26W
WB0TXL
--

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