How do I make LED's stick?

[GM50 4164]

Walthers Goo works very well. Use a small amount, if that is possible, hold in place for a minute and done. Try not to move, the wires may move it around and you wouldn't want that. Yes its brown but a little amount to hold it at first works fairly well for me.

[peteski]

Walthers Goo works very well. Use a small amount, if that is possible, hold in place for a minute and done. Try not to move, the wires may move it around and you wouldn't want that. Yes its brown but a little amount to hold it at first works fairly well for me.

Like WD40 or masking tape, Walthers Goo is universal - it sticks to everything! 
Not my primary choice, but it will do the job satisfactorily in some instances.

[DKS]

Actually, paper towel might be an accelerant. Well, something in the paper. Maybe moisture?  I think it is more to it than just wicking away excessive amount of glue on the joint.  I use Bounty paper towels and sometime I drip few drops of CA on the towel. It sets fairly quicky (especially thin CA), even heating up and emitting "smoke".  So maybe when you wick away the excess glue, you migth be setting up a chain reaction.

Yes, it's possible that trace moisture in the paper might contribute to the bonding process, but it's probably fairly insignificant compared to the effect of wicking, which allows the long molecule chains to form more rapidly and create the bond. However, if the paper has any cotton content, then the CA will have a strong, rapid exothermic reaction with it, hot enough to emit smoke. That's why you should avoid spilling CA on cotton clothing at all cost--it can get so hot it can cause skin burns, not to mention bond the cotton to the burned skin.

 

[Chris333]

Same thing when I clean up CA with a q-tip=smoke 

[peteski]

Same thing when I clean up CA with a q-tip=smoke 

Yup, Q-tip=cotton - like DKS said.

From https://en.wikipedia.org/wiki/Cyanoacrylate

Reaction with cotton, wool, and other fibrous materials
Applying cyanoacrylate to some natural materials such as cotton (jeans), leather or wool (cotton swabs, cotton balls, and certain yarns or fabrics) results in a powerful, rapid exothermic reaction. This reaction also occurs with fiberglass and carbon fiber. The heat released may cause serious burns, ignite the cotton product, or release irritating white smoke. Material Safety Data Sheets for cyanoacrylate instruct users not to wear cotton (jeans) or wool clothing, especially cotton gloves, when applying or handling cyanoacrylates.

[Jbub]

I put some CA on receipt (thermal) paper. Yup, that stuff has carbon in it. It smokes and turns black.

[peteski]

I put some CA on receipt (thermal) paper. Yup, that stuff has carbon in it. It smokes and turns black.

It is not carbon - the exothermic reaction of he CA hardening triggers the dye release in the thermal paper.

For more then you ever want to know see: https://en.wikipedia.org/wiki/Thermal_paper

You can "draw" a line on that paper with your fingernail.
Usually, the coating will turn black when heated, but coatings that turn blue or red are sometimes used. While an open heat source, such as a flame, can discolor the paper, a fingernail swiped quickly across the paper will also generate enough heat from friction to produce a mark.

The surface of the paper is coated with a solid-state mixture of a dye and a suitable matrix; a combination of a fluoran leuco dye as an example. When the matrix is heated above its melting point, the dye reacts with the acid, shifts to its colored form, and the changed form is then conserved in a metastable state when the matrix solidifies back quickly enough. The reactant acid in thermal paper is often bisphenol A (BPA).

[Urodoji]

I use E6000 applied with the tip of a toothpick.

[MetroRedLine]

Howdy all,
     I am trying to upgrade lighting in some of my locos. I am having a hard time gluing the 0603 led's to the numberboard/headlight plastic.
     Regular CA just is not working for me. For example..I drilled a hole in rear head light plastic in order to recess the LED, inserted the LED used regular CA..did not hold.
     So what can be done to glue the LED's?

Cya, Y-it

I've actually had great luck with this:



Only $2.50 at Michael's! It's semi-elastic, which means it's in a tacky state when not yet fully dry, allowing you to position your LEDs in place for maximum brightness. Also, you can paint it with black acrylics to avoid light leakage.