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Glass Drills:

Holes in glass plate are traditionally cut using a water cooled diamond core drills or with a metal cylinder "cookie cutters" used with an abrasive slurry. The tool using a  glass drill   is an inexpensive way of cutting holes .This is also a good method to cut windows for sealing into glass tubing.

Equipment: Drill Press:
Material: Mounting Adhesive - Armco Co. Crystal Bond 509 recommended
Glass tube about 2-3 inches in length - OD to match the hole desired
Metal Plate on which to mount glass tube
Abrasive Grit - 220 grit silicon carbide

Use the same speed of low RPM, as in metal cookie cutters, while starting the glass drill contact slowly without much downward pressure. Allow for equal material loss from the glass drill as in the glass plate being drilled.

 

Silver Plating - Brasher Process
Three Part Solution Mix for Internal Plating

Solution I

2 liters distilled water, 50-g silver nitrate. Store in a dark glass bottle.

Solution II

2 liters distilled water, 90-g potassium hydroxide.

Solution III

800 ml distilled water, 80-g cane sugar, 100 ml ethyl alcohol, 3.5 ml nitric acid. Age 30 days or boil 30 minutes before using.

 

Solutions are used at the following ratio:
I : II : III = 64% : 32% : 4% by volume

 

Solution Required (ml )

Solution I

Solution II

Solution III

50

32

16

2

100

64

32

4

150

96

48

6

200

128

64

8

250

160

80

10

300

192

96

12

400

256

128

16

500

320

160

20

600

384

192

24

700

448

224

28

800

512

256

32

900

576

288

36

1000

640

320

40

1500

960

480

60

2000

1280

640

80

 

To use: Add ammonium hydroxide (dropwise) to solution I. and Stir the solution while adding the ammonium hydroxide until precipitate clears. Add solution II to I. Stir the solution while adding ammonium hydroxide until the precipitate is slightly cloudy. Pour the solution into glass vessel to be silvered. Add solution III and then stir/shake slightly to ensue the proper mixing while working 

Warning: wear working protective clothing and promptly and safely, discard unused mixed solutions.


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