Best way to remove flux and melted plastic off PCB? - diyAudio
Go Back   Home > Forums > General Interest > Everything Else

Everything Else Anything related to audio / video / electronics etc) BUT remember- we have many new forums where your thread may now fit! .... Parts, Equipment & Tools, Construction Tips, Software Tools......

Please consider donating to help us continue to serve you.

Ads on/off / Custom Title / More PMs / More album space / Advanced printing & mass image saving
Reply
 
Thread Tools Search this Thread
Old 17th June 2013, 08:29 PM   #1
diyAudio Member
 
Join Date: Jul 2010
Location: Chicago
Default Best way to remove flux and melted plastic off PCB?

I have hardened flux on my pcb and I'm looking for an efficient way to remove it. I can heat it up with a soldering iron and wipe, but that's time-consuming. The liquid flux has hardened and I want the pcb clean.

Secondly, I don't know how it happened, but when I used a wick to remove excess solder, black plastic melted into the pcb The wick and soldering iron was clean, so was the pcb. Maybe there was melted plastic underneath the solder that I didn't notice. Is there a way to remove it without damaging the pcb and components?
  Reply With Quote
Old 17th June 2013, 09:35 PM   #2
diyAudio Member
 
Join Date: Apr 2004
Location: manila, philippines
try to soak in danatured alcohol.
  Reply With Quote
Old 17th June 2013, 09:39 PM   #3
diyAudio Member
 
john curl's Avatar
 
Join Date: Jul 2003
Location: berkeley ca
Sometimes you have to loosen hardened flux with a dental pick. This is what I use.
  Reply With Quote
Old 17th June 2013, 10:01 PM   #4
diyAudio Member
 
Join Date: Nov 2008
Location: Victoria,TX
Blog Entries: 1
Hi,
I used acetone to clean the PCB after soldered the components.
  Reply With Quote
Old 18th June 2013, 11:09 PM   #5
diyAudio Member
 
cogsncogs's Avatar
 
Join Date: Jul 2003
Location: Wayne, West Virginia
Quote:
Originally Posted by Headfi Fanatic View Post
Secondly, I don't know how it happened, but when I used a wick to remove excess solder, black plastic melted into the pcb The wick and soldering iron was clean, so was the pcb. Maybe there was melted plastic underneath the solder that I didn't notice. Is there a way to remove it without damaging the pcb and components?
Not plastic, but burnt, overheated rosin (flux) most likely from the desoldering braid. I've used alcohol, acetone and/or flux remover with cotton tipped wooden cleaning sticks. You just have to be careful not to soak the board with it as you don't want it to wick into components like electrolytic capacitors.
  Reply With Quote
Old 19th June 2013, 02:40 AM   #6
diyAudio Member
 
Join Date: Jul 2010
Location: Chicago
Quote:
Originally Posted by cogsncogs View Post
Not plastic, but burnt, overheated rosin (flux) most likely from the desoldering braid. I've used alcohol, acetone and/or flux remover with cotton tipped wooden cleaning sticks. You just have to be careful not to soak the board with it as you don't want it to wick into components like electrolytic capacitors.
So that's what it was. Thanks!
  Reply With Quote
Old 19th June 2013, 07:10 AM   #7
diyAudio Member
 
Join Date: Jul 2003
Location: Dona paula, Goa
Chloroform melts plastic.

Gajanan Phadte
  Reply With Quote
Old 19th June 2013, 07:11 AM   #8
AJT is offline AJT  Philippines
diyAudio Moderator
 
AJT's Avatar
 
Join Date: May 2003
Location: Palatiw, Pasig City
denatured alcohol and lacquer thinner works for me...
__________________
the best advertisement for a good audio design is the number of diy'ers wanting to build it after all the years....never the say so of so called gurus....
  Reply With Quote
Old 19th June 2013, 08:10 AM   #9
diyAudio Member
 
wrenchone's Avatar
 
Join Date: Feb 2004
Location: Silicon Valley
90% Isopropanol works well, and you can get it at most drug stores. The water in the usual 70% rubbing alcohol renders it much less effective. Soak the board a bit, and scrub it with a tooth brush. The iso is compatible with most plastics, and also is compatible with electrolytic capacitors.

If you want to spend the money, the flux remover mixtures marketed by folks like MG Chemicals are very effective, and formulated not to harm most electronic materials. As a bonus, they wash off magic marker and silicone grease quite well, so you can use the stuff to clean old silicone grease off a heat sink, as well as the random gobs that seem to magically leap onto your clothes, (especially if you're wearing black). I also use the stuff as a general purpose cleaner and degreaser.

Chlorinated solvents of any sort are taboo, as they slowly rot electrolytic caps from the inside out. Acetone is a no-go, as it eats several types of plastics used in electronics, most notably, polystyrene.
  Reply With Quote
Old 19th June 2013, 08:43 PM   #10
diyAudio Member
 
Join Date: Jul 2010
Location: Chicago
Quote:
Originally Posted by wrenchone View Post
90% Isopropanol works well, and you can get it at most drug stores. The water in the usual 70% rubbing alcohol renders it much less effective. Soak the board a bit, and scrub it with a tooth brush. The iso is compatible with most plastics, and also is compatible with electrolytic capacitors.

If you want to spend the money, the flux remover mixtures marketed by folks like MG Chemicals are very effective, and formulated not to harm most electronic materials. As a bonus, they wash off magic marker and silicone grease quite well, so you can use the stuff to clean old silicone grease off a heat sink, as well as the random gobs that seem to magically leap onto your clothes, (especially if you're wearing black). I also use the stuff as a general purpose cleaner and degreaser.

Chlorinated solvents of any sort are taboo, as they slowly rot electrolytic caps from the inside out. Acetone is a no-go, as it eats several types of plastics used in electronics, most notably, polystyrene.
Will they work on burnt flux? They're harder to remove and I haven't worked on the pcb for a year.
  Reply With Quote

Reply


Hide this!Advertise here!
Thread Tools Search this Thread
Search this Thread:

Advanced Search

Posting Rules
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is Off
Trackbacks are Off
Pingbacks are Off
Refbacks are Off


Similar Threads
Thread Thread Starter Forum Replies Last Post
How do you remove flux residue after soldering? 777funk Construction Tips 40 25th September 2010 11:31 AM
How to remove rear seat and plastic??? BlacknRedGT Construction Tips 2 24th April 2009 12:38 AM
double-sided pcb: how to easily remove a soldered component? jarthel Parts 30 29th September 2006 10:51 PM
How to remove thru-hole IC from multi-layer PCB? Alexandre Parts 20 21st February 2006 09:32 AM
Melted NeoPro5i ultrachrome Multi-Way 13 20th September 2005 10:37 PM


New To Site? Need Help?

All times are GMT. The time now is 12:46 AM.


vBulletin Optimisation provided by vB Optimise (Pro) - vBulletin Mods & Addons Copyright © 2014 DragonByte Technologies Ltd.
Copyright ©1999-2014 diyAudio

Content Relevant URLs by vBSEO 3.3.2