This is an excellent question, but our problem is slightly different. Our production line uses a no-clean wave soldering process and in-line BON testing. Using the continuous flow manufacturing philosophy, we test the boards as soon as they are built(previously we used a batch process, with a stand alone BON). Our problem is that the boards need to be cool, basically room temperature, before they enter the BON, or else you will get false resistor readings due to the high temperature. We presently have a series of muffin fans after the wave and a length of conveyor to cool the board before testing. We are still working to improve this, including trying Dave Hillmans recommendation of fans blowing over the chilled water pipes(we started this before his response--I was glad to see that great minds think alike LOL). The secret with fan cooling is high air flow volume with low force or pressure. This way you get the maximum cooling effect while avoiding the ESD effect of high pressure air. However, to cool a board down to room temperature in a short time period, you need to blow air that is cooler than room temperature. The cooling curve is asymtopic, it is the last 50-100 degrees that is the hardest! I am experimenting with a vortex tube, blowing cold air on the product, but this is extremely loud. There is a conveyor company that markets an enclosed FIFO buffer tower with an air conditioner, this is rather expensive, not something we are trying right now. I have recommend to many Equipment vendors(Electrovert, Seho, etc), that they need to create a stand alone piece of equipment similar to what is found in the cooling section of the newer reflow ovens today, i.e. a one meter long cooling section that can be used to cool boards down after the wave solder or any other operation. SEHO presently has one under development.. If anyone has any other recommendations, I look forward to hearing them QUESTION: not trying to be a smart alec, but in the original question, the problem is taking ltoo ong to cool down because of the large ground plane, thus the solder joint is liquid for a long period of time, and the component probably moves while the solder is cooling. I thought the proper term for this was a "disturbed solder joint" not cold solder joint. Just wondering!?! Ed Holton Lectron Products [log in to unmask] ------------- Original Text From: C=US/A=INTERNET/DDA=ID/TechNet-request(a)ipc.ipc.org, on 4/2/97 11:23 AM: Does anyone have any information on what type of fan (ionizer) works best at the end of the wave solder machine? We are having some problem with cold solder joints on some of the products with large ground planes. They are taking too long to cool. I was going to place an ionizer that will blow onto the bottom of the board as it leaves the wave solder machine. We are running an Electrovert 2000/s. Also does anyone have any information or experience with how far away from the wave itself the fan should be placed? Any help is appreciated. ------------------------------------------------------------------------ ------- Ryan Chase - Manufacturing Engineer Harris Canada Inc. Wireless Access Division (403) 295-5036 FAX (403) 295-8862 *************************************************************************** * TechNet mail list is provided as a service by IPC using SmartList v3.05 * *************************************************************************** * To subscribe/unsubscribe send a message <to: [log in to unmask]> * * with <subject: subscribe/unsubscribe> and no text in the body. * *************************************************************************** * If you are having a problem with the IPC TechNet forum please contact * * Dmitriy Sklyar at 847-509-9700 ext. 311 or email at [log in to unmask] * *************************************************************************** *************************************************************************** * TechNet mail list is provided as a service by IPC using SmartList v3.05 * *************************************************************************** * To subscribe/unsubscribe send a message <to: [log in to unmask]> * * with <subject: subscribe/unsubscribe> and no text in the body. * *************************************************************************** * If you are having a problem with the IPC TechNet forum please contact * * Dmitriy Sklyar at 847-509-9700 ext. 311 or email at [log in to unmask] * ***************************************************************************