Homebrew PCBs

I used to use concentrated HF at work routinely.  Later we had to be specifically certified to work with HF.  It's very nasty stuff.  I looked at amazon and there are a number of etching products, for porcelin.  http://www.amazon.com/s/?ie=UTF8&keywords=hydrofluoric+acid&tag=googhydr-20&index=aps&hvadid=22879189327&hvpos=3o2&hvexid=&hvnetw=g&hvrand=1455058631626177776&hvpone=&hvptwo=&hvqmt=e&ref=pd_sl_2yx2giqcys_e

I searched for Hydrofloric Acid (HF).  HF cannot be stored in a glass bottle.

I bought a gallon of stuff that contained 3% HF and 3% Hydrochloric, a commercial product for cleaning windows.  I accidentally got some Superclean on the house windows.  It seems to etch it, but it worked wonders.  I only needed a little bit, but it beat replacing the windows.  Every once and a while I use it to clean some bottles used to store iced tea.  Takes less than 30 sec to clean the bottle.  I have to find some way to use it.  Disposal would really be an issue, (neutralizing with baking soda, but ph testing would be worthwhile.

--- On Fri, 3/15/13, Rick Sparber <rgsparber@...> wrote:

From: Rick Sparber <rgsparber@...>
Subject: [Homebrew_PCBs] slightly OT: etching the OD of a cylinder to create a graduated dial
To: Homebrew_PCBs@yahoogroups.com
Cc: "'Granthams'" <granthams@...>
Date: Friday, March 15, 2013, 11:08 AM
















 



  


    
      
      
      This has been a favorite problem of mine for a long time. 



It is standard practice to engrave the outside diameter of a cylinder with

tick marks and numbers in order to make a graduated dial. I have done this

by laser printing, mirror image, to clear plastic and then bolting it on the

OD with the toner on the inside:



http://rick.sparber.org/Articles/CD/CDM/d.pdf








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