Glue for affixing LED’S in models

[hon30critter]

tstage

Half a day???  The Testors Clear Parts Cement I mentioned is basically canopy glue and it begins setting up in 5 min - i.e. if applied thinly to the surface you are affixing the LED to. 

Hi Tom,

I hope you know that I was kidding with the "half a day" comment. The canopy cement that I have, which is 'Formula 560' by Pacer, does take a long time to dry. It certainly isn't suitable for mounting LEDs. I'll have to try the Testors stuff.

Thanks,

Dave

[mthobbies]

JDawg

Just curious what everyone uses to affix leds. I've been using silicone but it takes forever to dry and it stinks my whole workshop up for hours. I though about super glue but I'm afraid that the solvents would cause problems. Any suggestions?

 

 

Why not try hot glue? It dries quickly and it is removable and flexible. Also it's clear, so it won't obstruct your light source.

 

Matt

[Bayfield Transfer Railway]

I attach surface mount LEDs with plain old Duco cement.

 

[snjroy]

For wiring inside locos, I cut thin strips of electrical tape to hold the wire, and apply some silicone for a better bond. The tape will hold it long enough to hold the wire. A bit of silicone over the tape will prevent it from falling in the long term. I prefer silicone because it is easy to remove.

Simon

[jjdamnit]

Hello All,

I have used CA (super glue) to affix LED headlights to shells with no ill effect other than having to completely destroy the LED when I wanted to remove it from the shell by drilling it out.

Now I use Micro-Mark PSA- -Pressure Sensitive Adhesive. It dries tacky, does not cloud the bulb and the LEDs can be removed without having to drill out the lamp or damage the shell.

Currently, I am re-motoring and upgrading the O.E.M. Bachmann Printed Circuit Board (P.C.B.) type decoders to Digitrax DH166D decoders in four GP40s.

These O.E.M. P.C.B. decoders had the LED lights built into the boards.

I am using 3mm "Warm White" LEDs.

There are mounts on the frame to hold the bulbs rather than attaching them directly to the shell. 

I will be using the Micro-Mark P.S.A. to hold the new LEDs in place. 

Hope this helps.

[BigDaddy]

I've not worked with anything smaller than 3mm.  I place it next to the light pipe and use blue painters tape to hold it in place so there is no tension on the wires to torque it out of place.

I use callk, same as I use for track.  It is easily peeled off if I need to remove the led.

[tstage]

hon30critter

gregc

canopy glue - Forms a firm, flexible clear bond

Hi Greg,

How do you hold the LEDs in place while the canopy glue dries? Canopy glue takes a long time to dry. I'm sure that you are not sitting there holding the LED in place for half a day!

Thanks,

Dave

Half a day???  The Testors Clear Parts Cement I mentioned is basically canopy glue and it begins setting up in 5 min - i.e. if applied thinly to the surface you are affixing the LED to.  There are also ways of jigging to hold things in place while the adhesive dries.  You would have to do that with 5 min. epoxy.

Tom

[tstage]

JJF,

As it may be obvious I'm not a fan of using CA for securing LEDs; hence the alternative suggestions.  If and when an LED burns out (and they do) or I inadvertantly fry it during an DCC installation (and I have), I don't want to run the risk of destroying it or the lens it is affixed to trying to remove/replace it.

Tom

[JDawg]

tstage

Two questions:

1. What type of LEDs?  Bulbs or SMDs?
2. Will you be affixing them to a lens or a lightpipe

 

I will be using either small smds or 1.8 mm standard LEDs.

The model is a walthers Plymouth ML8. I normally use 3mm LEDs, but the lenses are smaller then other locomotives I've worked on. Thanks for all the awesome suggestions. I think I have some of this stuff lying around!

Some suggested that superglue would also work. I was concerned that the solvents would break down the outer layer of plastic on the LED causing it to become milky and/or diffuse the light. Maybe this is totally wrong.

[richhotrain]

tstage

Two questions:

1. What type of LEDs?  Bulbs or SMDs?
2. Will you be affixing them to a lens or a lightpipe?

Good questions.

Water Level Route

What kind of models?  Locomotives or buildings?  

More good questions.

If locomotives, headlight/Mars light, ditch lights?

What brand and model?

Rich

[Oldngrey]

I have been successfully using 2 products:

1. Black Tack available on ebay from the UK. Wonderful stuff and stops all light bleed around it too.

2. I have also tried Aleene's Instant Tacky. Same idea as black tack, but in white from the USA. I prefer black tack.

The idea is to get those tiny smd leds into place and hold them there on their hair wires. It also works for the 3mm leds too. Works well for ditch lights, number boards and headlights.

[Overmod]

What I used for fabricating clear components and light pipes/fibers  was the clear epoxy marketed for 'glass repair'.  This is non-etching to most if not all the transparent plastics and is 'engineered' to have a cured index of refraction similar to normal glasses or PbO2 'crystal' so gluelines may be less visible.

Problem is that this product only appears sporadically in stores, so you may have to search around for it and pay a premium plus shipping...

Incidentally I don't think the active 'junction' in a LED would be injured by transient exposure to typical glue solvents for the time involved in making a bond.

The problem with most 'paste' epoxies like PC-7 is getting good metering and then mixing at the relatively small quantities involved for most modeling jobs. With sufficiently fine tip tools and patience (and perhaps judicious use of a loupe) one of the two-part stick products might be used... but use strictly separate tools to get the resin and hardener.

[hon30critter]

gregc

canopy glue - Forms a firm, flexible clear bond

Hi Greg,

How do you hold the LEDs in place while the canopy glue dries? Canopy glue takes a long time to dry. I'm sure that you are not sitting there holding the LED in place for half a day!

Thanks,

Dave

[gregc]

canopy glue - Forms a firm, flexible clear bond

[Water Level Route]

What kind of models?  Locomotives or buildings?  I use hot glue in buildings.  Works well, dries fast.

[hon30critter]

Hi JDawg,

I have been using quick setting epoxy with success for several years. The quick setting stuff usually claims that it will set up in 90 seconds but it never seems to work that fast. However, it is quicker than 5 minute epoxy.

One thing that I have found to be absolutely critical is that the LED has to be held exactly in the right spot until the epoxy is solid. That takes a lot longer than 90 seconds for '90 second' epoxy. I have found that, even after the epoxy feels firm, the LEDs can still shift out of place.

I have also found it easy to see if the LEDs are in the right place if they are illuminated while you are working with them. That is especially true when doing things like classification lights or vehicle headlights/tail lights where the opening in the lens is very small, but it is important when doing locomotive headlights and number boards too. I have a couple of different power supplies on my workbench so I can light up the LEDs without needing to have the final circuit in place. Don't forget the resistors!! It is very frustrating to smoke an LED that you have just spent 10 minutes glueing in place!

Epoxy can be removed if things go wrong, but the LEDs are usually destroyed in the process.

I have never considered using putty to mount LEDs. There are two part epoxy putties available that might make it a lot easier to hold the LEDs in place while the putty sets as opposed to using a liquid epoxy. Interesting suggestion! Has anybody tried this?

Cheers!!

Dave

[RR_Mel]

I’m always screwing around with all kinds of LEDs and for the most of it I use Harbor Freight Super Glue/Super Glue Gel in the 0.1 oz tubes.  I’ve been using Super glue for LEDs for years without any problems.

The most complex LED glue job is my Mel Mars light, three 3mm LEDs glued together on a 5mm LED lens.

I have about a half dozen Mars lights working in my E7s for several years.

https://drive.google.com/file/d/1BpyxY12gIfkm04Y_jRph5xdahu4MJ7Mb/view?usp=sharing


Mel
 
Modeling the early to mid 1950s SP in HO scale since 1951



My Model Railroad    
http://melvineperry.blogspot.com/
 
Bakersfield, California
 
Aging is not for wimps.

[tstage]

Two questions:

1. What type of LEDs?  Bulbs or SMDs?
2. Will you be affixing them to a lens or a lightpipe?

Suggestions:

• 3mm LED to a lightpipe -> heatshrink - It's flexible and it's strong enough to secure both the lightpipe and the 3mm LED.  The black heatshrink will also absorb stray light.
• 3mm LED to lens -> Drill out the lens 3/16" deep with a #32 (0.116" OD) drill bit - The LED will press fit into the hole w/o any adhesive.  You can use Elmer's glue or silicone adhesive if you'd like but it's not necessary.
• SMD to lens -> Testors Clear Parts Cement - It holds well and dries clear.

Any of the above will stay in place but will allow the LED to be removed, if desired - w/o the fear of damaging the surfaces of either the lightpipe or the lens.

Tom

[JDawg]

Maybe a putty or epoxy product? I'm looking for something without lots of solvents. 

[JDawg]

Just curious what everyone uses to affix leds. I've been using silicone but it takes forever to dry and it stinks my whole workshop up for hours. I though about super glue but I'm afraid that the solvents would cause problems. Any suggestions?