I thought it might be useful to do a quick thread on boro annealing schedules so that the info is in one place. I've copied bits from various other threads, so that we have one thread to look at rather than several.
I think there may well be as many boro schedules as there are boro workers - but I hope these will give a start to anyone wanting to have a try with the hard stuff.
Boro can (specially for small pieces) be garaged with soft glass, run through the soft glass annealing schedule and then batch annealed later - useful to know if you just want to play at the end of a session using soft glass.
http://mikeaurelius.wordpress.com/2007/12/26/annealing-cycles-for-torch-made-glass/I used to use this schedule: (all in degrees C)
garage at 505, then ramp up to 565 at 80 degrees to anneal for an hour. I then ramp down at 90 to 510 to let the glass "rest" for 10 mins and then down to 370 and switch off
but now use one closer to Glenn's (Dendrobium) below, with a longer annealing time (my stuff has got larger) and a striking part at 590 added in. I have seen striking temps go up much higher than this - quite a bit over 600.
Hope he won't mind, but here's Glenn's schedule (also degrees C):
"I've seen various advice on garaging everything from 510 up to 540, but the important bit is ramp up to 567 for about 1hr, then a slow ramp down (about 46deg per hour) to about 525 for a short rest (10mins to 1hr depending how thick) then a slow ramp down to 370. Thicker bits will need a longer anneal, and if you've got ruby colours you will need to do an extra ramp up before the anneal to about 582 to strike the reds which tend to strike better in the kiln rather than in the flame"
