hobo9941:
How long does Shoo Goo take to dry before the LED would stay in place?
Thanks
Dave
I'm just a dude with a bad back having a lot of fun with model trains, and finally building a layout!
I have found a lot of uses for Shoo Goo, which is found in the shoe dept at Walmart. It's sort of like stronger rubber cement, but you can pull something free of it. It's used for fixing shoes and glueing soles. But I have found a number of other uses for it. You could pull a bulb out of it without breaking anything. A little dab on a toothpick would hold a bulb in place and allow you to remove it easily.
You're very welcome, Dave. Yes, clean surfaces do make a difference with any tape.
I've even machined with double-stick tape when securing something with hold-downs with wasn't practical. The downside was you had to run the operation dry - i.e. without coolant. Generally, it wasn't an issue because either the piece was thin, or I ran the operation removing small amounts of material at a time so the endmill never got very hot.
Tom
https://tstage9.wixsite.com/nyc-modeling
Time...It marches on...without ever turning around to see if anyone is even keeping in step.
Hi Tom:
I have had a roll of Kapton tape for several years now and I have never been impressed with its holding power. In fact I just bought a new roll from Litchfield Station hoping it would be better, but it doesn't seem to be a whole lot stickier. That led me to reflect on your statement that the surfaces must be grease free. It dawned on me that the likely reason the tape wasn't holding is probably because there was oil from my fingers on the surfaces. Duh!
Next time I will get out the alcohol and Q-tips.
I hadn't thought of using foam tape. It certainly is sticky enough. However, I'm still leaning towards epoxy because the exact position of the LED can be adjusted easily before the epoxy sets. Us old guys you know - we're as stubborn as heck!
Thanks for the suggestions.
BTW, I replaced both the front and rear blown LEDs on the Atlas RS-3 and soldered the negative wire to the 1K resistor pad on the TCS A4X decoder board. Works a lot more reliably now...and no snaps, crackles, or pops.
hon30critter Tom: tstage I do everything I can NOT to glue in bulbs; I could use other glues besides epoxy that would be easier to remove, but the drying time then becomes a problem. Its bad enough having to wait a few minutes for the epoxy to set. Keeping the lights properly lined up while something like Aileen's Tacky Glue sets up would be difficult. I'm open to suggestions. Dave
Tom:
tstage I do everything I can NOT to glue in bulbs;
I could use other glues besides epoxy that would be easier to remove, but the drying time then becomes a problem. Its bad enough having to wait a few minutes for the epoxy to set. Keeping the lights properly lined up while something like Aileen's Tacky Glue sets up would be difficult.
I'm open to suggestions.
Hey Dave,
Have you considered double-sided or double-stick tape - e.g. the 3M version that comes in its own dispenser? That stuff holds amazingly well. You just have to make sure that the mating surfaces are grease-free. You can also get thinner foam tape that also holds well.
You might also be able to utilize Kapton tape. Have the wires come off either side of the SMD LED (like it's being suspended) and secure it with the Kapton tape. It sticks well enough repeatedly that you can make minor adjustments and not worry about it sagging or pealing off.
Just a few ideas...
Thankfully, Ed, the LEDs on my Atlas RS-3 are very excessible. The hood was still off when I was running the locomotive and the first POP! blew the entire rounded lens cap right off the LED. Never have seen one blew that thoroughly before. Usually it's just a flash of light and then it goes dark.
tstageOh, well. LEDs are easy to change out.
Unless they're buried deep inside the boiler as I found out just last week with a Proto 2000 Heritage 2-10-2!
The thing that threw me off was that I was changing a sound-for-sound decoder, removing the QSI factory one and replacing it with a Loksound select.
Moving right along with the install everything went swell! Since I didn't encounter the resistors with the QSI board it just didn't sink in that I'd need them with the Loksound! This was probably my hundredth decoder install, too!
With the engine on the Sprogg test track it only took me 1/500th of a second to be reminded of the resistor's absence!
THEN I started digging around for the LED! On their Berkshire it is a simple plug-in behind the smokebox front.
Oh, no... this baby was installed right after the motor was put in! I mean it is right next to the flywheel! Fortunately I had the explosion diagram and discovered the hidden screw I needed to remove that you had to pry off the steam dome to find!
Fortunately, all is good, now. No guarantees that I won't do the same thing sometime in the future... just gotta laugh and chalk it up to human nature!
hon30critterUnfortunately I have encountered a number of situations where there didn't seem to be any alternative to using glue.
I encountered that situation not long ago as well, Dave. Trying to align two 0603s behind an Athearn Genesis dual sealed beam on a F7B backup light. 1.5mm fiber optic was my only resource. Took me two tries but it worked out OK. I used a Highliners dual sealed beam housing as a pattern and glued the LEDs to a backing plate with the exact alignment. Took two tries but I finally got it...
Regards, Ed
tstageI do everything I can NOT to glue in bulbs;
Good advice. Unfortunately I have encountered a number of situations where there didn't seem to be any alternative to using glue. For example mounting 0603s behind locomotive or vehicle headlights requires that the LED stays exactly in place. If they are out by even a tiny amount the light won't come through the lens properly. I used to use 3mm LEDs and like you said, there are a number of ways to secure them without gluing. However, I have done a number of installations where the 3mm LEDs took up too much space.
Dave,
I do everything I can NOT to glue in bulbs; either incandescent or LEDs. I like to use either a press fit (in the shell), black heat shrink (around a light pipe), or Kapton tape so that I can replace the bulb when it goes.
I have forgotten the resistors for LEDs and 1.5v bulbs a few times. More often then not the lights have been buried in epoxy or the wires CA'd in place.
Now I get the resistors out and put them on the workbench where I can see them during assembly. No doubt I'll still miss one or two.
Ohhhhhhh, that sound....You know...the one you get when you've replaced the circuit board that came with your locomotive with a quality DCC circuit board decoder...and you test it out on the programming track for the first time. Everything is going well...the locomotive moves smoooooothly back and forth - like it's supposed to...and you press the HEADLIGHT button on your throttle and...POP!...No more headlight.
You scrunch your brow...You look at the wiring diagram that came with the decoder - the very diagram you've been using to make sure that EVERYTHING is wired correctly...and THEN...you discover that there are TWO diagrams: One for incandescent bulbs and one for LEDs...so that you can utilize the onboard resistors. And now with your eyes fully opened, you can clearly see the subsequent...POP!...of the other LED giving up the ghost.
Oh, well. LEDs are easy to change out. Better that than a blown decoder. Looks like I'll be unpacking my Weller soldering station when I drive back to OH this weekend.
P.S. Despite the above earlier incident, the replacement TCS A4X decoder works beautifully.