> At 05:58 PM 5/23/2002 -0700, you wrote: > >I'll be teaching a pinhole class, constructing cameras from Quaker oatmeal > >canisters. I'd like to avoid using knives to cut the opening for the pinhole. > How about a punch? If you were to insert a piece of soft wood (like a 2x4 > clamped to the edge of a table) into the oatmeal box for a mandrel, you > could smack a short piece of brass tubing (or anything else you could find > lying around) with a hammer and punch out a pretty good circular > hole--especially if you filed the edges of the tube to make it slightly > sharp (but not skin-cutting sharp).
The above is much like a cork-borer. This is a tube with one end sharpened to bore a hole in a cork. You may be able to get one at a very good hardware store or from a scientific supply house - maybe even a wine-making store. We have a couple of sets of them for making different sized holes in corks and stoppers. They should cut through cardboard Gord > > --------------------------------------------------------- Gordon J. Holtslander Dept. of Biology hol...@duke.usask.ca 112 Science Place http://duke.usask.ca/~holtsg University of Saskatchewan Tel (306) 966-4433 Saskatoon, Saskatchewan Fax (306) 966-4461 Canada S7N 5E2 ---------------------------------------------------------