Problems soldering Luxdrive K2 star?

First post here, so go easy, I'm no expert at electronics. Hopefully this is the right subforum for the question.

I've put together a few LED lights for reef aquarium and vivarium lighting using Luxeon Stars by Philips (Luxeon IIIs) and some by Luxdrive (both rebels and K2s). I just used a radioshack soldering iron with radioshack solder, and soldered by hand. I have no problem wiring the Philips stars, as the pads seem to be pre soldered, however the Luxdrive stars give me a major headache. The solder simply does not want to stick to those bare pads and repeatedly pops off halfway though the project.

I am probably using a completely wrong type of solder or something, and if theres some easier way to attach wires to those pads please help me out. If it can be done with materials that are readily available locally, and don't have to be mail ordered that would be AWESOME.

TIA for any advice you can give me.
-Tim

are you heating the parts to be soldered too? solder will stick to it better if you hold the iron on the solder pad for a few seconds more before applyig solder

3 tips:
1. Use flux
2. Heat the parts to be soldered
3. Use a higher quality iron or a soldering station.

A cheap Hakko or Weller clone will do a much better job than the Radio Shack special, and won't dig a hole in your pocketbook. If you can afford an actual Hakko, it's well worth the price.

Oh, :welcome: