On Mar 12, 2009, at 10:36 AM, Dan Reed wrote: > Fred, Thanks for researching this.I'm very interested in using steam > for puffing up compacted felt, and am looking forward to your > technique. How to keep the glue contact surface intact in the key > bushings is my question. > > Dan Reed > Dallas, Tx It's a matter of timing, of how long you apply the steam. If you are removing bushings, you need quite a few seconds, maybe even a minute or so, to loosen the glue joint enough so the bushings will come out easily. Bushings and the glue that was used do vary, so you do need to pay attention. But I have found that a fairly rapid steaming as I described, where the bushings get one second or so of steam, possibly repeated once, does not loosen the glue joint enough to make the bushing loose. Most of the time, the felt swells and the glue joint isn't affected at all. And following with the key bushing iron, again paying attention to time (less than one second per bushing, possibly repeated), this will tend to reset the glue if it has become loosened a bit (kind of like ironing veneer to get it to restick where it has bubbled up). I iron all my rebushing jobs. Occasionally I'll have a bushing that wasn't quite glued tightly - usually because I let the glue get too cold before inserting the felt and the caul. I find that the iron will melt the glue and set the joint adequately. But you don't want too high a heat, or too long a time. Or you will melt the glue enough to pull it into the felt. It's not as touchy as the description makes it sound. Just common sense. Like ironing clothes, where you can scorch the fabric if you have the iron set too hot, or you don't keep it moving. But it's not real hard to iron clothes successfully. There is plenty of leeway if you are paying attention. The best way to learn this technique, and not be worried about the result, is to try it next time you have a rebushing job. Just try it on a section of bushings, running the steam and following with the iron. I think you'll find that there isn't a lot to worry about. Regards, Fred Sturm University of New Mexico fssturm at unm.edu
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