Newbie question: Do you Tin the LED?

[Viper1]

Howdy,

Yet another newbie question.

When wiring up an LED do you tin both the LED and the wires or just the wires?

Just paranoid about blowing the LED

[Rathan]

Always tin both. With flux, a good tip, and a nice hot iron you can do it nice and quick.

[Silver Serpent]

Depends on the LED. Some of them (like the Seoul P4) come with pretinned pads. Others (LEDEngin 10w) don't. If the pad isn't tinned already, you should do so.

[captain_mills]

My Seoul P4 White did not come tinned. I had to do both the wires and the LED...

[Silver Serpent]

My P4 greens and blues were pretinned. It would appear they're not all the same, so look at them closely before you begin. Either way, be sure that the LED pads and the wires are tinned before you attempt to join them. Your wallet will thank you later when you don't have to purchase new LEDs :)

[Viper1]

My P4 greens and blues were pretinned. It would appear they're not all the same, so look at them closely before you begin. Either way, be sure that the LED pads and the wires are tinned before you attempt to join them. Your wallet will thank you later when you don't have to purchase new LEDs :)

How will i know from visual inspection whether or not the LED is tinned?

I have a P4 and part of the reason I raised the question is that the square pads on the Led board have a silverish colour rather than the green grey colour on the shop picture would this indicate that it is tinned or just a variation in p4's?

Many thank's for your help and patience

[Knighthammer]

I have a P4 and part of the reason I raised the question is that the square pads on the Led board have a silverish colour rather than the green grey colour on the shop picture would this indicate that it is tinned or just a variation in p4's?


Chances are if they are silver in color already, then they are pre-tinned. If your wires are tined already, it should just take (literally) a couple seconds to solder the two together. The P4's I've worked with and the Luxeons have all been pre-tinned. I recently got a LEDEngin and it most definately is not.

[Skottsaber]

RULE OF THUMB: TIN EVERYTHING
(With the possible exception of your fingers)

[Loachri MacTalabh]

Skott said it plane and clear. Tin everything, that way there is no doubt.

[Azmaria Dei]

RULE OF THUMB: TIN EVERYTHING
(With the possible exception of your fingers)

QFT. and yes, don't tin your fingers...

[captain_mills]

Got it... tin everything... I still don't think my Seoul P4 White was pre-tinned even though the pads are silvery...

:)

[Tarrell]

QFT. and yes, don't tin your fingers...

Haha helpfully tip, do you smell burning?

[Viper1]

well theres good news and bad....

My saber kit arrived a couple of days ago and after practiceing tinning decided to have a go at putting all the electrics together. For the most part everything went ok. I did find that i had to use clips to hold the wire as i struggled trying to hold both the solder and wire in one hand. Unfortunately i managed to make a right pigs ear of the LED.

I Decided to pre tin the the LED pads and although a bit fiddley managed to successfuly solder the leads to the LED pads. Unfortunately i found out when i had compleated the saber that the Led was not in the correct postion for the Lens mount to fit over the top...DOH!

So after removing the Leads from the LED and changing the position I tried to re- solder the Leads to the other set of pads but for some reason i just couldn't tin the other pads. Any solder that went onto the pads just collected on the soldering iron and wouldn't seem to stick to the pads. After several attempts decided that i had screwed up the LED and called it a day. I'm trying not to beat myself up and telling myself to use this as a learning experience. I'v ordered another LED kit, buckpuck and spare LED just in case. I figure the extra parts in the LED kit will be useful spares.

Although overall (other than the LED) everything went together ok i still have a couple of basic questions about soldering:

1) when tinning are you supposed to heat up the wire you are going to tin with the Iron and then touch the wire anywhere with the solder or does the solder have to be right next to the iron to melt? Same thing with the LED pads, do you heat the pad then touch the pad with the solder right next to the iron, or is the pad supposed to be hot enough to melt the solder whever the solder is.

I ask this as when i tried to heat up a wire and then place the solder on the wire the wire never seemed hot enough to melt the solder. I found I had to place the solder wire almost directly on the soldering iron for it to melt and then i was concerned the solder was coming from the Iron rather than being fresh solder off the spool. I'm actualy wondering if i need a better soldering iron than my battery operated one.

2) Any idea why the solder just didnt seem to want to stick to the LED pads the second time around?

I hope this all makes sense and sorry for this being such a long post!

[Azmaria Dei]

your first problem is not enough heat... your second problem is your battery powered soldering iron. please get a real one and try again.

also, when tinning wires/pads, heat the wire/pad and let it melt the solder - it forms a good bond that way.

[Viper1]

your first problem is not enough heat... your second problem is your battery powered soldering iron. please get a real one and try again.

also, when tinning wires/pads, heat the wire/pad and let it melt the solder - it forms a good bond that way.


Thank's for that, i had an idea the iron may have been part of the problem. When buying a new soldering iron do i need to make sure it of any patticular specification ie Wattage, ideal temperature etc?

[Rafalema]

Did you try to tin it while it was on a heatsink?

[Skottsaber]

As for tinning, solder is attracted through surface tension by more solder. As per my tip above, you want to tin EVERYTHING (that includes your iron tip). When tinning a wire, use your tin to heat up the wire and then also add solder, it doesn't matter if you "premelt" the solder on your spool by touching it quickly to the iron tip while it is on the wire, this can be helpful. If you're pretty quick you can also just put solder on your tip and move it up and down your wire before the flux boils off, it works most times for me.

EDIT: And also what Raf said, don't solder an LED while it is on a heatsink. It won't work.

[Jedi-Loreen]

As for tinning, solder is attracted through surface tension by more solder. As per my tip above, you want to tin EVERYTHING (that includes your iron tip). When tinning a wire, use your tin to heat up the wire and then also add solder, it doesn't matter if you "premelt" the solder on your spool by touching it quickly to the iron tip while it is on the wire, this can be helpful. If you're pretty quick you can also just put solder on your tip and move it up and down your wire before the flux boils off, it works most times for me.

I think you meant "iron", not "tin". ;)

When I tin wires I hold them in my "helping hands" and touch the iron tip to the bottom of the wire, with the solder against the top. I don't even touch the solder strand with the iron. As soon as the wire gets hot enough, it will melt the solder onto itself. I move the iron tip back and forth against the wire to make sure it's evenly coated with solder and remove the iron before the wire insulation starts to melt.

If you can't get solder to adhere to the other pads, try a very light sanding on them (be careful of the LED dome). Roughing those up a bit could help.

This is the type of helping hands I have:
5227

[Viper1]

EDIT: And also what Raf said, don't solder an LED while it is on a heatsink. It won't work.

Ahaaa...yep that would be my mistake, possibly more than the battery operated iron. it did seem strange that it worked fine for the wire and not the LED.

now that i think about what a heatsink does it kinda makes sense that this would cause problems with soldering..duh:rolleyes:

[Skottsaber]

I think you meant "iron", not "tin". ;)

Well... the tin on the iron ;)