I’ll have to see if we have an SEM. It is very possible this pot had SAC305 in it. I can tell you it killed a carbide drill bit. From: David Hillman [mailto:[log in to unmask]] Sent: Tuesday, March 07, 2017 1:50 PM To: TechNet E-Mail Forum; Nutting, Phil Subject: Re: [TN] grunge at bottom of tinning solder pot Hi Phil - what you have is an IMC which is more dense that solder so it sank to the bottom. It may be FeSn which is pretty tough to remove. Use the SEM to figure out what IMC you have and then it may be possible to dissolve it with another solder alloy (i.e. SAC305, etc.). Dave Hillman Rockwell Collins [log in to unmask]<mailto:[log in to unmask]> On Tue, Mar 7, 2017 at 12:12 PM, Nutting, Phil <[log in to unmask]<mailto:[log in to unmask]>> wrote: I have two wire tinning solder pots that have not received the proper day-to-day maintenance and now there is solid crud filling all but about ¼ of the crucible. I have tried chiseling it out and drilling it out. All I end up with is dull tools, even carbide drills. Other than buying new solder pots or replacing the crucibles are there any suggestions for removing this super hard stuff? Phil Nutting | HVP Development Engineer | Excelitas Technologies Corp Lab: +1 978.224.4332<tel:%2B1%20978.224.4332> | Office: +1 978.224.4152<tel:%2B1%20978.224.4152> 35 Congress St, Salem, MA 01970 USA [log in to unmask]<mailto:[log in to unmask]<mailto:[log in to unmask]>> www.excelitas.com<http://www.excelitas.com><http://www.excelitas.com/> [Excelitas R_emailsig] Please consider the environment before printing this e-mail. ________________________________ This email message and any attachments are confidential and proprietary to Excelitas Technologies Corp. If you are not the intended recipient of this message, please inform the sender by replying to this email or sending a message to the sender and destroy the message and any attachments. Thank you.