How to melt white plastic stubs that hold LED PC Boards

[jimlips]

Hello:

I recently replaced the lower clamshell frame on my P3A due to hairline fractures in one of the motor "arms" on the old one. It all went OK, but I'm not sure how to melt the two little white plastic "pins" that pop up through the holes in the four LED PC board assemblies. I'm guessing I could use a soldering iron, but it sure seems hokey. Is there a better, more professional way? I don't want to damage anything.

Thank you!

 

[Steve7777]

Hello:

I recently replaced the lower clamshell frame on my P3A due to hairline fractures in one of the motor "arms" on the old one. It all went OK, but I'm not sure how to melt the two little white plastic "pins" that pop up through the holes in the four LED PC board assemblies. I'm guessing I could use a soldering iron, but it sure seems hokey. Is there a better, more professional way? I don't want to damage anything.

View attachment 110827

Thank you!

Carefully softening the pins with a soldering iron is, indeed, one way to do it, until you are able to gently lever the board out. Be very careful, of course, as you don't want to crack the board! They might not be as secure after refitting even if you remelt the tabs, so I'd probably use a few of dabs of hot glue on the edges of the boards to refix them.

Another way could be to use a small grinding wheel on a Dremel-type tool to grind the plastic tabs down and then again use a hot-glue gun to refix them.

 

[jimlips]

Maybe I wasn't clear; I have already removed the LED boards, and am trying to secure them into the new clamshell. How do I melt the stubs to flatten them out and secure the board?

 

[N017RW]

They were likely ‘melted’ using ultrasonics. Much safer as there is no heat applied. It is the result of friction delivered by a tool.
Consider glue in your case and don’t worry too much as the interface is not structural.

 

[Dragonfly Joe]

Maybe I wasn't clear; I have already removed the LED boards, and am trying to secure them into the new clamshell. How do I melt the stubs to flatten them out and secure the board?

Jim, I would use the flat blade on a full size soldering gun. The blade is meant for melting and cutting plastic. using the flat side of the blade would melt a knob on the top of each of the posts to secure the board. It would not get hot enough to worry about damaging the PC board.

 

[captainmilehigh]

+1 on the hot glue.

 

[artfuldodger]

Heated putty knife. Not too hot. You want to soften and flatten the plastic stub not melt it. A soldering iron will ruin it if it is too hot.

 

[chazz]

Did it more then one time with a solder iron. Takes less then a tenth of a second. After you do it you wonder why you even questioned why not do it that way.