[R-390] Desoldering part 2

[Norman Ryan]

Hi,

Good routine overall, but I'd add this: Where possible, after clipping leads off the post, undo its mounting screw and finish desoldering the post's terminal outside the chassis.  

These little guys are very susceptible to breaking under heat and physical stress, so one should take every precaution to avoid damage to the posts.

For desoldering I use a Weller DS-600 that I found on eBay that was missing its bottom cover.  Due to that and bidders' apparent lack of interest I got it really cheap.  

Cooper Industries (Weller's parent company) graciously sent a replacement cover gratis.  Ya gotta love that kind of technical support!

Boatanchor restoration is strictly a hobby and retirement pastime for me, thus the high cost of state of the art desoldering gear is beyond my reach financially.  However, the current thread on desoldering (plus the raves about Hakko) has me rethinking this.

73 de Norman, KG4SWM





On Thursday, November 7, 2013 12:51 PM, wli <wli98122 at yahoo.com> wrote:
 
Standard procedure is to heat and unwrap using needle-noses and dental picks. This puts a lot of stress and torque on the post, and can fracture them, as we have seen.  What I do, is first clip off the wrapped lead of the offending component flush with the post using a real sharp flush wire cutters, whose nose has been filed narrow. Then with a hot 100W narrow tip iron, touching the post momentarily causes that component to literally fall off. It takes only seconds to just heat those portions of the post holding the old lead, and lessens the damage caused by conducted heat to neighboring components like resistors or coils.
>
>
>Principle is to use a hot enough iron to loosen the solder for removal, and not heat up the entire assembly. 
>
>Reassembly is another matter, since now the entire post and other leads require cleaning and re-tinning, and you should use hemostats or other narrow heat sinks to prevent collateral thermal damage.
>
>At least, that is my routine........    W. Li
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