Try it!!!! (Was - Re: One More PCB Dishwasher Question)

From: Pete Turnbull <>
Date: Sat Dec 29 18:49:26 2001

On Dec 29, 12:53, William Donzelli wrote:

> I would think the thermal shock of the chips hitting the hot water would
> be a failure mechanism. Hot air and hot water are different things, even
> at the same temperature. The thermal resistance of a water to ceramic (or
> plastic) junction is much, much lower, than one with air, so during the
> first seconds of the wash cycle, the chips go from ambient
> temperature to something rather high. Lots of stress results, especially
> if only some of the chip's package gets wet. Preheating the boards would
> help reduce the shock greatly, but home dishwashers do not do that (not a
> good idea to cook the food onto the plates before trying to wash them!).

Do most American dishwashers start with hot water? Most European ones
start with cool water and heat it as they run.

Pete						Peter Turnbull
						Network Manager
						University of York
Received on Sat Dec 29 2001 - 18:49:26 GMT

This archive was generated by hypermail 2.3.0 : Fri Oct 10 2014 - 23:33:42 BST