Even the no clean type has some conductivity. We did analog boards
with the stuff and still had to wash it off. Rosin never caused
any problems even into the 100's of megohms.
Dwight
Subject: Re: NorthStar Horizon restoration question
From: paulkoning at
comcast.net
Date: Tue, 24 Jun 2014 11:16:21 -0400
To: cctalk at
classiccmp.org
On Jun 23, 2014, at 5:52 PM, Ian McLaughlin <ian at platinum.net> wrote:
Hello all and thank you for adding me to the
list.
I am in the process of restoring a NorthStar Horizon machine. The boards in this machine
have a significant amount of flux residue on them - it certainly appears that this
particular machine was constructed from a kit. My question is about this flux - should I
be removing it as part of my cleanup, or should I leave it in place? I know that this
isn't a super-collectible machine or anything, but I've never come across this
issue in any other machine in my collection, and I was wondering what the general
consensus was. I'm perfectly aware of the corrosive nature of the flux and how to
remove it, however this flux has been there for 35+ years.
Thanks in advance for your thoughts.
If it?s a kit, the flux is 99% likely rosin flux. That?s been used with electronics for
many decades, and while in theory it can be removed, I?ve never heard of anyone doing it
nor of any device suffering from having it stay on.
Modern industrial fluxes are not rosin, but either water-soluble flux or ?no clean? flux.
The latter is designed to be left on without ill effects. The former definitely needs to
be removed (but you can do that with warm water). Either can be bought nowadays at least
from electronics supply companies (you?re not likely to find them at Radio Shack or the
local hardware store). But I would not expect that?s what you are looking at.
Rosin flux residue is often rosin-colored ? yellowish or light brown translucent blobs.
paul