Hi Harry I can't argue on that one, after all the leading boiler making expert in the UK (Alec Farmer) advocates cooling the boiler with a watering can fitted with a rose. I guess all the professional boiler makers must quench their boilers, they would take too long to make otherwise. The point I was making that (from what I've heard) if you have used silver solder from a dodgy source, you run the risk of cracking when quenching. Regards Ron ----- Original Message ----- From: "Harry Wade" <hww@xxxxxxxx> To: <modeleng@xxxxxxxxxxxxx> Sent: Wednesday, October 19, 2005 12:13 AM Subject: [modeleng] Replacable Tips now silver solder >.............. In years of reading I can never recall a single > cautionary reference to quenching and I've quenched nearly 100 copper > boilers and never had a crack, but then I've never used anything but new > silver solder from a known source. Quenching serves a useful purpose. -- No virus found in this outgoing message. Checked by AVG Anti-Virus. Version: 7.0.344 / Virus Database: 267.12.4/142 - Release Date: 18/10/2005 MODEL ENGINEERING DISCUSSION LIST. To UNSUBSCRIBE from this list, send a blank email to, modeleng-request@xxxxxxxxxxxxx with the word "unsubscribe" in the subject line.