How I can unit test Dapper Extension Method?

Cutting quartz glass tubing

• Last ditch attempt at reclaiming a damaged unit: I have a water steriliser for a garden pond. It consists of an ultra-violet fluorescent tube, which passes through a larger chamber through which water is pumped. The fluorescent tube is separated from the water by means of being contained within a test-tube shaped quartz glass tube, about a foot long and an inch-and-a-half wide, the wall thickness being approximately 1mm (sorry to mix metric & imperial measurements.. I was brought up on the changeover!) cutaway view, side-on: water water inlet outlet __| |________________________| |_ | water | | /''''''''''''''''''''''''''''' | | ========================<---------- fluorescent tube | \.............................<---------- glass 'test tube' | water |\ '''''''''''''''''''''''''''''''''' \___damaged lip of 'test tube' Now, my problem is, that whilst cleaning the innards of the unit, the 'lip' of the quartz glass 'test tube' became damaged - a piece being chipped off the rim. This means that the tube no longer seals in it's mounting, which is a rubber 'o' ring lining the inside diameter of a hole at one end of the unit's casing - water can pour out at the end via the chipped portion of the tube. What I'm wondering, is that since there is plenty of spare length on the quartz tube, could I repair the unit by slicing off the end of said tube - so that the open end of said tube would once again seat correctly in it's rubber-lined hole at the end of the casing? Specifically, I remember a method of making 'attractive ornamental glass rings' from a childhood arts and crafts book. As I remember, the method involved filling an old glass bottle with oil, and then plunging a red-hot poker into the oil. The result was supposed to be that the bottle cracked cleanly around it's circumference, at the level of the oil's surface. You then repeated the process to produce your glass rings. I'd like to know if I can employ this method to take off about 1cm from the end of my tube, removing the damaged section, and leaving a clean, level rim. What would be the procedure - is oil the correct thing to use, should it be pre-heated, should the glass be pre-scored where the break is intended to occur? Is there anything else I should do to try and ensure best results? If information you supply results in my reclaiming this unit, a tip will be in order. If not, and things go 'pear-shaped', nothing's lost, I shall just have to replace the full unit. If you need question clarification please ask, I'll be paying attention. Thanks for your time.

• Answer:

  gan... I believe the following tool will be more effective than an angle grinder, and I hope it falls within your definition of "readily available". Item 79022, on the following page, is a glass cutter designed to cut tubes of up to 1.5 inches in diameter, and is available from the Wheeler-Rex Company: http://www.wheelerrex.com/glass_cutter.html I don't see a way to order online. Contact info: Wheeler Manufacturing - division of Rex Int'l USA P.O. Box 688 3744 Jefferson Road Ashtabula, OH 44005 Ph: 440-998-2788 Fax: 440-992-2925 Toll Free: 1-800-321-7950 KHUE.com offers a variety of stained-glass and glass-related products, including the bottle cutter on this page: http://www.khue.com/dept/cutt/bott.htm While the bottle cutter itself might be a bit wide for your purposes, the instructions for its use are very relevant to your situation. The instructions start here: http://www.khue.com/dept/cutt/bott1.htm It continues with instructions for etching the glass, using a very light etch, and only one revolution. The next step outlines heating the etched line with a candle, followed by cooling it with an ice cube, which causes the etch to become a crack, allowing the piece to be easily removed: http://www.khue.com/dept/cutt/bott3.htm These procedures, in combination with a cutter such as the one above, should make it a 'snap' to cut your tube. If you are not willing to wait while the cutter above is delivered, you might even find a way to use a regular glass cutter, assuming you can find a way to stabilize the etch through some alignment process as might be used on a table saw, e.g. Perhaps you could hold the glass cutter in a vise, and find some means of rotating the tube against it with adequate stability to produce a straight line around the tube. You could practice on bottles until you got it down pat. I'm not sure, but perhaps the process and the results would be improved by the use of glass cutting oil available on the KHUE site here: http://www.khue.com/dept/chem/cutto.htm Presumably, this reduces splintering on a microscopic level, and produces a cleaner etch. Maybe 3-in-1 oil would work just as well? Please do not rate this answer until you are satisfied that the answer cannot be improved upon by means of a dialog with the researcher through the "Request for Clarification" process. sublime1-ga Searches done, via Google: glass tube cutter ://www.google.com/search?num=50&hl=en&lr=&ie=UTF-8&oe=UTF-8&safe=off&q=glass+tube+cutter glass cutting tube ://www.google.com/search?num=50&hl=en&lr=&ie=UTF-8&oe=UTF-8&safe=off&q=glass+cutting+tube&btnG=Google+Search "glass cutting" tube ://www.google.com/search?hl=en&ie=UTF-8&oe=UTF-8&q=%22glass+cutting%22+tube