> Hello Kit, > > You have me very curious about this. > Did you freeze the pipe with the toffee inside it ?
I had a bit of brass tubing about 12mm diameter and 40cm long, and I annealed it before starting (heat it until it glows dull red, then cool it). Then I drilled a shallow hole in a bit of wood to hold the pipe vertical and to act as a plug. When I say toffee, all I did was boil some sugar and water until the sugar went glassy. To test this, you get a glass of cold water and drop a teaspoonful of the mixture into the water. As the mixture thickens, it gradually gets stiffer and stiffer and eventually ends up quite glassy and brittle. When it was about the consistency I thought would work (fairly stiff, but not too glassy) I took the mixture off the heat and stirred it to get rid of any large bubbles. Then when it looked like a clear syrup (just a few tiny bubbles) I poured it down the pipe and left it to cool at room temperature. I had to top up about 10% of the pipe due to shrinkage as it cooled. When it was tacky, I cooled it under a cold tap then left it for about half an hour until it was at room temperature. Then I bent it against a radiused piece of wood. I am making a jig to get exactly the curve I want, but what I can say is that it bends nicely. I've made some quite tight bends and apart from one place (where I think I may not have annealed properly) the tubing is very round with no ripples. Afterwards, I just left it in a tub of hot water and the sugar dissolves out. > Or just bend it at room temperature? This was part of my objective - I knew of the ice method but heard you had to work very quickly. I've also used a low-melting temperature alloy when I went to a trumpet-making workshop earlier this year, which is my only experience of instrument-making. I would like to make some crooks, so I looked into buying cerrobend/bendalloy, but it was very expensive and more toxic than I would want to use in the kitchen. Toffee is quite an interesting material in that it is actually a liquid that flows very slowly, but can also shatter if you hit it with a hammer. I think my boiled sugar was probably acting the same way. There were some cracking noises as I bent the pipe, but the toffee clearly wasn't just breaking at a few places otherwise the pipe wouldn't have bent smoothly, which it did. I figure there's some room left for experimentation. I think it might currently be too stiff and brittle for bending really wide-bore tubing like the bell of a horn. My pure sugar was probably a bit more glassy than was ideal. Fudge is basically the same recipe + lots of butter, but would probably be too soft. Presumably a recipe somewhere in between might be ideal. But... It worked fine for the tubing I was bending which is wide enough for me to make crooks for a horn, or another trumpet if the mood takes me. Kit > > Paul Navarro > Custom Horn > > > -----Original Message----- > From: Kit Wolf <[email protected]> > To: [email protected]; The Horn List <[email protected]> > Sent: Wed, 25 Mar 2009 10:28 pm > Subject: Re: [Hornlist] Ice horn - pipe bending > > A new alternative: toffee. > > I've been meaning to try it for a while, but only got round to > experimenting this evening making a crook for a baroque trumpet. It > works > well. > > Kit > > >> Herb Foster wrote: >> >> "Hasn't ice been used as a filler for bending tubing?" >> >> Yes it has, although not straight ice. It is mixed with detergent to >> raise the melting temperature to around 40* F (around 5* C) and make > it >> more pliable. Otherwise the ice just shatters into sharp bits and it > can >> deform the outside of the bend. >> >> Stuart A. de Haro, >> >> Custom Horns, Leadpipes, Brass Repair and Modification >> >> (217) 377-1462 >> >> [email protected] >> >> http://www.deharohorns.com >> >> >> >> _______________________________________________ >> post: [email protected] >> unsubscribe or set options at >> > http://music2.memphis.edu/mailman/options/horn/c.j.l.wolf%40newcastle.ac.uk >> > > > -- > Sometimes my Email program gives the wrong return address. If you have > any > trouble replying to me, use '[email protected]' and not > 'n802...' > > Sorry for any confusion > > _______________________________________________ > post: [email protected] > unsubscribe or set options at > http://music2.memphis.edu/mailman/options/horn/corno911%40aol.com > > > -- Sometimes my Email program gives the wrong return address. If you have any trouble replying to me, use '[email protected]' and not 'n802...' Sorry for any confusion _______________________________________________ post: [email protected] unsubscribe or set options at http://music2.memphis.edu/mailman/options/horn/archive%40jab.org
