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Electronics => Repair => Topic started by: Old Don on October 05, 2017, 12:38:41 pm

Title: reattach lifted traces with Loctite Red?
Post by: Old Don on October 05, 2017, 12:38:41 pm
I got thinking about what product to use on lifted traces or solder pads that one often finds on previously repaired boards. Not missing traces, but ones still there, but up in the air. One of the problems is the need to solder replacement components to the repaired copper pads after doing the trace repair. That takes heat which kills a bunch of cements or glues, but Loctite Red after curing is rated to 500 deg's F (260 deg's C) and I've used it in the past to glue together not heavily stressed broken metal parts where epoxy has failed. So I was wondering if you use a low temp solder if it might be possible to not lift the repaired traces a 2nd time and therefore end up with a decent result.

Has anyone tried this or some other high temp product? I'm going to try this on the next board in need of TLC that I find. Thoughts?
Title: Re: reattach lifted traces with Loctite Red?
Post by: sprintcarfan on October 05, 2017, 03:59:32 pm
Loctite Red (272) is anaerobic, so it might not ever cure properly on a thin trace?
Title: Re: reattach lifted traces with Loctite Red?
Post by: joeqsmith on October 05, 2017, 04:34:40 pm
I use Loctite Tak Pak for traces and Black Max for bonding wires. If things are really unstable, I have resorted to epoxy. 
Title: Re: reattach lifted traces with Loctite Red?
Post by: keymaster on October 05, 2017, 07:26:35 pm
CW2500 from Chemtronics . it can withstand  temperatures from -48 to 315 °C for a few seconds . it is for coating but it does what you want just fine .
Title: Re: reattach lifted traces with Loctite Red?
Post by: stmdude on October 05, 2017, 08:43:08 pm
Here's a video of a guy that really pays attention to the details when it comes to repairing lifted pads (and traces)

https://www.youtube.com/watch?v=vx50YtEC2S8 (https://www.youtube.com/watch?v=vx50YtEC2S8)
Title: Re: reattach lifted traces with Loctite Red?
Post by: KL27x on October 05, 2017, 09:23:36 pm
Quote
...Black Max for bonding wires.
I bet joeqsmith pays attention to details, too. Bonding wires? Seriously!?
Title: Re: reattach lifted traces with Loctite Red?
Post by: Cyberdragon on October 05, 2017, 11:00:33 pm
Quote from: KL27x on October 05, 2017, 09:23:36 pm
Quote
...Black Max for bonding wires.
I bet joeqsmith pays attention to details, too. Bonding wires? Seriously!?

Louis Rossmann uses bonding wires. :P Plus it's kinda hard to glue a trace if it doesn't exist anymore.
Title: Re: reattach lifted traces with Loctite Red?
Post by: The Guy on October 05, 2017, 11:18:03 pm
Use whatever the dentists use for gluing metal stuff to our teeth... I'm sure it's the best product in the universe.
Title: Re: reattach lifted traces with Loctite Red?
Post by: joeqsmith on October 06, 2017, 11:52:21 pm
I watched his entire video.  I wonder how much time was spent cutting the new pads.  Nice workmanship. 
Title: Re: reattach lifted traces with Loctite Red?
Post by: Old Don on October 07, 2017, 01:18:41 am
Quote from: The Guy on October 05, 2017, 11:18:03 pm
Use whatever the dentists use for gluing metal stuff to our teeth... I'm sure it's the best product in the universe.

I'm sure it is strong and it cures with UV light, but I don't think teeth get heated to 250 deg's C and that's a problem with soldering repaired traces.
Title: Re: reattach lifted traces with Loctite Red?
Post by: Neomys Sapiens on October 07, 2017, 01:49:22 am
TB 43-0127 calls for epoxy for repair of delaminations and for setting of replacement eyelets