Why use a thermal epoxy?

[jldindc]

I have just purchased some SSC P4 stars and khatod 17mm reflectors for my two PT EOS. I plan to follow some of the advice here to replace the original EOS star with the P4. I have never soldered before, and just purchased a cheap weller soldering iron and some silver solder.
My questions:
1. Some here in the forum suggest adding a heat sink to the back of the P4. Some have used a sanded pre "79 penny, and then used thermal epoxy to "glue" the penny to the back of the star. Why must one use thermal epoxy? Can't I just use some superglue? My local store is charging a rediculous $19. for a small amount of thermal epoxy. I have some Arctic Silver 5 paste that I use for computer CPU heatsink connections. Couldn't I just use my existing paste and superglue in place of the thermal epoxy?
2. How do I de-solder the wire contacts from the existing star? I can't seem to buy any "de-soldering" wick at my local store. Google searches about soldering mention this de-soldering wick.
3. Since I've never soldered before, what do I need to know about soldering the wire contacts to avoid ruining my new star?
Thanks for any input.
-Jan

 

[GoingGear.com]

Here is a tutorial on desoldering:

http://www.hardwaresecrets.com/article/164

Here is an article/video on soldering:

http://www.makezine.com/blog/archive/2007/01/soldering_tutor_1.html

Dunno about the thermal epoxy, since I have not messed with modding too much yet.

MAKE has an awesome tutorial on soldering in one of their issues (can't rememeber which one). Either way, you should go and buy all of their back issues, since it is a wonderful publication.

 

[zgurl]

As for the thermal, you better not mix your glue and thermal silver paste. Otherwise you will loose the thermal transfer capacity of the silver paste.

As far as I remember, the led in the eos does not really need to be sticked to whatever: it is kepts by the wires and the optics. Personnaly, I just put a small drop of thermal grease between the back of the led and a small aluminium plate I had to use because the reflector was too short to keep the LED in place. No need for epoxy there.

 

[walkabout]

I suggest you do a search of this site. I did a while ago and found a number of interesting alternatives, including a) thermal paste + crazy glue on the edges and b) JB Weld high-temperature epoxy. Purists will insist on the high-end stuff, however, and will give you an authoritative explanation why.

 

[ace0001a]

Check this out:

http://www.overclockers.com/tips683/

 

[Long John]

Hello jldindc and welcome to CPF

I always prefer a propper heatsink and I'm using AA-epoxy to install Led's.
But you can try this, it's very basic, but it could work:

to1: the problem is, you have to isolate the bottom of the SSC. So you can try to use nail-polish to isolate a copper penny. Put your existing thermal paste to the bottom of the Led and install it on the penny. Then with 2part-epoxy (not superglue) fix the Led at the black plastic part and the penny, not underneath of the Led.

to2: you can cut of the wire of the old Led.

to3: be sure that your iron is at the right temperature, solder the wires to the connections at the SSC, it needs about1-2 seconds.

My suggestions are not the perfect way to do a propper mod, but they can work with your equipment.

Good luck and best regards

____
Tom

 

[chevrofreak]

to1: the problem is, you have to isolate the bottom of the SSC.

Not an issue with the PT EOS since the star is the heatsink and it doesn't contact any other metal.

 

[Long John]

Not an issue with the PT EOS since the star is the heatsink and it doesn't contact any other metal.

So then the mod is much easier

 

[nein166]

I have just purchased some SSC P4 stars...

The STAR is a great heatsink adding a penny won't help much more. Theres no need to try removing the emitter from the aluminum star. I'm not familiar with the EOS but if its not metal the heat won't get out of the heatsink anyhow. Just don't try running the LED over 500ma and it should last a long time and still put out a lot of light.