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Working with .005" thick Glass         Cutting the glass to size 
    
    Since we are dealing with glass here, it's very important to 
    take proper safety precautions: 
      
      Wear good eye protection.
      Handle glass with care, edges can be sharp.
      Use adequate lighting.
      Good eye magnification is always helpful.
      Uncluttered work surface to keep track of any stray 
      pieces.
      Use clean tools.
    Your working surface should be 
    very clean and flat. We like to use the polished marble 1-foot square 
    floor tiles that can be found at your local home improvement center (Home 
    Depot, Lowe's, etc.). We've seen them on sale for as little as $1 to $2 
    each. If you choose to go this route, inspect them prior to purchase and 
    pick the best you can (unscratched or chipped with minimum pitting). Hint: 
    These are ground and polished to  a very flat surface. They work very 
    well for general model assembly where squaring-up parts for bonding is 
    required (i.e.; styrene structures).
    For the glass cutting process, we 
    recommend placing a clean sheet of paper (colored paper is fine) on the work 
    surface. This provides a slight non-scratching cushion for the glass and 
    helps it stay in place. Holding the paper in place with masking tape can 
    help.
     For scribing, you'll find that 
    diamond absolutely works the best. There are literally hundreds of small 
    diamond coated tools available in hardware stores, hobby shops, home 
    improvement centers, on the Internet, probably Sears tool section, Ebay, 
    etc.. There are Dremel thin cutting disks (about $6 for an 8-pack with 
    mandrel), scribing tools, cutters, and so on. What you'll want is something 
    small and light-weight.  
    As an alternate, you can use the 
    broken pieces of Dremel sanding disks. These are typically of carbide/epoxy 
    composition and the broken pieces will have relatively sharp corners which 
    can make a good scribing tool. 
    
    To scribe the glass, a gentle touch 
    is required. If you're going to scribe a straight line (most common), we 
    recommend using a piece of styrene strip as your straight edge. This, we 
    feel, is a better choice than a steel straight edge for two reasons. First, 
    styrene is relatively soft and has some "give" to it. It won't scratch the 
    glass or chance cracking it as easily as any pressure on a steel object 
    will. We recommend a strip wide and thick enough to maintain straightness 
    but not thicker than, say, .040". Choose a length of about 2" to3".
    With the glass on the paper, align 
    the styrene straight edge on the glass where you want to scribe. Gently 
    hold down on the styrene, positioning your fingers above, below, and in the 
    center of the glass along the styrene. This helps hold the glass so it won't 
    move while scribing.
    Lightly drag your scribing 
    tool along the side of the styrene to scribe (scratch) the glass. Too 
    lightly and no scribing will be done, too much pressure and you'll break of 
    move the glass. Too lightly would be a better choice to start with. After 
    you've done this once or twice, you will definitely get a "feel" for what 
    works best for you. Caution: Try not to drag your scribe across the 
    beginning or ending edges of the glass while exerting the downward pressure 
    or you may make small chips on these edges. Try starting and ending you 
    scribing process just at, or slightly inside these edges. When you flex the 
    glass to break it, the fracture will follow your general scribed line. The 
    very small amount at top and bottom that weren't scribed will fracture along 
    the same approximate line. This is much better than unwanted chipping or 
    cracking of the glass.
    If your fingers are clean and dry 
    (which they should be), pick up the scribed glass by the edges and gently 
    bend it like you would to break a scribed piece of styrene only with a 
    much gentler touch. It will almost instantaneously break along the 
    scribed line.
    The more you handle the glass, the 
    bigger the chance is that it will get smudged by the oils and dirt trapped 
    in your finger prints. Minimizing handling and careful storage in a clean 
    environment will save you time ultimately. Since we are dealing with glass, 
    you can use most any type of cleaner if required. We've actually used Windex 
    and a small Q-tip on the finished and mounted product with great success.
    The first time you cut this glass, 
    the results may not come out perfectly to your liking, but like anything 
    else, you will quickly get a "feel" for it. In a very short time you'll be 
    able to repeatable cut tiny sections without any problems.   Bonding .005" thick glass You can use virtually and bonding agent: CCA, epoxy, rubber 
cement, Walthers Goo, white glue, etc. Your choice really depends on what you're 
bonding the glass to and what type of bond you need. If you plan to use this 
glass where there may be wide variations in temperature (on portable modules 
containing structures that may be stored in cold, then moved to hot locations), 
you may want to use a fairly flexible adhesive. This will allow for variations 
in thermal expansion between glass and the product you're bonding to or the 
possibility of your product flexing and cracking the glass. However, for the 
most part, thermal expansion differences probably won't be extreme enough to 
cause problems. Besides, we've actually cracked a window in one demo example and 
it looks fantastic! That's not something you can do with clear plastic. For an HO demo we built, we used extra-thin, instant-cure (1-3 
seconds) CCA. We placed the cut glass over the window opening and set a small 
weight on the center of the glass to hold it in place. Placing a small drop of 
the CCA on a toothpick tip, we touched the tip to the edge of the glass by the 
edge of the window opening. Capillary action caused to CCA to "draw" into the 
point where the glass and styrene window touch. We did this at each corner of 
the window. In a few seconds, the glass was securely in place. When viewed from 
the structure front, we could see (under magnification) a very tiny glue-line 
where the bond exists. This was essentially unnoticeable even under 
magnification, but at one tiny point a little extra glue was evident on the 
glass surface. This was easily scraped off without causing any damage or 
scratching.   
  An N-Scale sized glass scraper Here's a simple little tool that will make cleaning our tiny windows much 
  easier. If you use a wet razor to shave (or know someone who does), it is 
  undoubtedly  one of those newer multi-bladed safety razors with the 
  packages of replaceable blades. What we want here is a used blade that we can 
  disassemble to (carefully) remove one of the cutting strips from. These are 
  typically tiny strips of very sharp, very thin stainless steel that are 
  spot welded to a small angled strip.  A typical example would be the Gillette 
  Sensor which has two cutting blades. These are held in place in the plastic 
  housing with two small aluminum straps, one at each end of the blade assembly. 
  Any jewelers screwdriver or small pick can be used to pry off these retaining 
  straps. These very sharp blades will then virtually fall out of the 
  plastic housing. We recommend cleaning the blades by soaking them in alcohol 
  and brushing them gently with an old toothbrush to remove shaving residue. 
  This will help reduce the possibility of infection from bacteria should you 
  accidentally nick yourself. Using a Dremel tool with a sanding disk mounted, use the edge of the disk 
  to cut a small notch on the blade edge about 3/32" to 1/8" from the end. 
  CAUTION: This blade is very sharp. Hold it carefully and securely when 
  grinding and wear good eye protection. Always note the direction 
  of rotation of the sanding disk and contact the part with the disk so that the 
  sanded debris is thrown away from you, not toward your face. The purpose of this small notch is to 
  allow you to bend the end of the blade at 90 degrees to the rest of the blade. 
  This will be your tiny scraper. While you're at it, sand the sharp edge off of 
  the length of the remainder of the blade. That way you can hold onto this 
  portion with you fingers without worrying about getting cut. The bent end of this 
  little tool is a very sharp little scraper that can be used to scrape right up 
  to the edge of a window and remove glue (or paint spatters in the case of our 
  HO lamp demo). 
    © 2008 Ngineering   |