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Hi Stephanie, half to an hour a sieve once you've done a few, which probably makes them less than half the price of the, too small, 100mm diameter brass Endicote type sieves. The mesh, which we do get from Locker Wire Co (shame that I never noticed they produced wire mesh but may have decided against it 25 or so years ago on the grounds of how do you fasten it to bowls!!) is nylon and extremely robust. I think it correct to say that the bowls and/or stitching have always given way first and several of our bowls have been in service for some years. Bowls are the most vulnerable because the dryng ovens too easily get turned up too high. We tend to use 2mm, 1mm, 500 and 300 micron although sometimes use commercial garden sieves, ca 8mm, to remove the largest stones after the sample has been weighed/volume taken. Does no-one else out there make their own sieves? Jacqui Quoting Stefanie Kahlheber <[log in to unmask]>: > Dear Jacqui, > > thanks a lot for your detailed description! Though, I have the > impression it is a lot of work - how long took it to sew one bucket? > Another question, how durable is the plastic mesh you use? Is it > suitable for coarse stony sediment, or is it easily cut by sharp stones > and ceramic fragments? > > Best regards, > Stefanie > > > Jacqui Huntley schrieb: > > >Dear Stephanie, > > > >We've tried various methods over the years although only with plastic mesh > as I > >don't know of a British source of wire mesh. We use plastic washing up bowls > as > >these often have a convenient ridge around the base that is easy to cut > against > >when removing the base. > > > >We've found the most reliable to be a double set of stitching, each with > saddle > >stitch, using either nylon fishing line or a heavy linen thread. For the > non- > >sewers, saddle stitch uses two needles and threads; pass one up through a > hole > >and the other down through the same hole, pull tight and move onto next > hole. > >We use a fine mounted needle heated in a Bunsen to make the holes but you > have > >to be careful not to make them too large. Alternatively use robust leather > >needles and a pair of pliers. > > > >As long as the mesh is cut quite closely to the outer line of stitching the > > >sieve is easy to clean of the little material that gets caught under the > mesh. > >We have tried all sorts of materials to seal this edge but they are either > >rigid and quickly break/flake or are flexible and get soft and sticky when > we > >put the bowls in the ovens to dry the flots. A thin layer of ordinary gloss > > >paint works quite well for the finer mesh sizes and I have a 300 micron > sieve > >made more than 10 years ago still in good working order - it has only had > 'one > >careful owner' though and not a lot of work recently! The mesh is white and > by > >using pale coloured bowls (luckily 'fashioinable' today!) it is easy to > check > >for possible contaminants. > > > >Look forward to seeing what other methods have been used.... > > > >Happy sewing, > >Jacqui > > > >_________________________________________ > >Jacqui Huntley, > >English Heritage > >North East Regional Science Advisor, > >Bessie Surtees House, > >41-44 Sandhill, > >Newcastle upon Tyne > >NE1 3JF > > > >Phone: > >Durham University: +44 (0)191 334 1137 (also fax/answer machine) > >Regional Office: +44 (0)191 269 1200 (Mondays: ... 1222) > >Mobile (preferred contact): +44 (0)771 3400387 > > > > > > > >