Golston 7W / Seoul Mod

[JohnF]

I removed the Lumileds LED 'star'. I added a steel washer to the base of the Seoul 'star' (purchased from DealExtreme) after using a Dremel to add 'indents' to the washer so the thickness of the Lumileds star and Seoul star are roughly the same. Mounted the Seoul star with no problem. The resistor installed in the Golston measures 1.2 ohms.

I can turn it on, and it seems bright as heck, with a decent focused beam, but I'm afraid to leave it on for more than a second for fear of frying the Seoul star.

I know absolutely nothing about the differences between the electrical characteristics of the original Lumileds star and the Seoul star I installed.

Help please - what have I done??? Like I say, it turns on fine, but - can I leave it on without frying anything in its current (no pun intended) configuration?

EDIT - BTW, it is a 'T' bin Seoul, if that matters, and the Golston is of course (2ea) CR123A's. As the resistor is 1.2 ohms, am I save driving the Seoul? (my meter doesn't measure DC current, although I should run right down to ratshack and buy one that does...) I'm sure you know I have no idea what I'm doing, or what I've done...

John F

 

[Lighthouse one]

Usually the led will fry real quick- if it's going to. Any chance you have a 17650 li-ion ?
This is 3.7--to 4.2 volts. and won't hurt any led.

 

[lexina]

I removed the Lumileds LED 'star'. I added a steel washer to the base of the Seoul 'star' (purchased from DealExtreme) after using a Dremel to add 'indents' to the washer so the thickness of the Lumileds star and Seoul star are roughly the same. Mounted the Seoul star with no problem. The resistor installed in the Golston measures 1.2 ohms.

I can turn it on, and it seems bright as heck, with a decent focused beam, but I'm afraid to leave it on for more than a second for fear of frying the Seoul star.

I know absolutely nothing about the differences between the electrical characteristics of the original Lumileds star and the Seoul star I installed.

Help please - what have I done??? Like I say, it turns on fine, but - can I leave it on without frying anything in its current (no pun intended) configuration?

EDIT - BTW, it is a 'T' bin Seoul, if that matters, and the Golston is of course (2ea) CR123A's. As the resistor is 1.2 ohms, am I save driving the Seoul? (my meter doesn't measure DC current, although I should run right down to ratshack and buy one that does...) I'm sure you know I have no idea what I'm doing, or what I've done...

John F

This is a very useful resistor calculator (link provided by Long John in another thread). By entering your supply voltage (2 CR123s = 6v), forward voltage of your Seoul emitter (indicated by the bin code) and desired current (I believe Seoul P4s can handle up to 1000 mA); you will get a recommended resistor value. If it is less than your 1.2 ohms, you are safe. If not, you could do what Lighthouse One suggested and use a 17670 instead.

http://www.metku.net/index.html?path=mods/ledcalc/index

Cheers,
lexina

 

[JohnF]

Usually the led will fry real quick- if it's going to. Any chance you have a 17650 li-ion ?
This is 3.7--to 4.2 volts. and won't hurt any led.

No, there are 2 ea. CR123A's in it. How can I find out the forward voltage of a 't' bin Seoul?

 

[JohnF]

Has anyone been able to drop in a regulator of some kind into the Golston w/ Seoul P4? I'd appreciate any advice here.

John F

 

[beefy6969]

Im in the same situation. I have a spare star laying around.

 

[Walt175]

I was able to install a DownBoy 750 in one of my Golstons. Took a LOT of dremeling to make it fit. It's currently driving a Cree XRE P4, but I have been considering swapping it for a SSC. It should work just fine.

 

[JohnF]

I was able to install a DownBoy 750 in one of my Golstons. Took a LOT of dremeling to make it fit. It's currently driving a Cree XRE P4, but I have been considering swapping it for a SSC. It should work just fine.

In a nutshell, how did you do this? What is brightness & runtime like? I was thinking of the downboy 1000...

John F

 

[Walt175]

I added the driver before Cree announced the XRE could be safely run at 1A. Like I said, I dremeled out the aluminium until the DB would fit. Took a few days working for an hour at a time. Bright as all heck, it's also my best throwing LED light. Was a pain getting the reflector to work with the XRE. Haven't done a runtime test.

I have been considering changing this over to a Seoul. Should involve little more then swapping the star, and taking out a spacer I had to use with the Cree.

 

[Long John]

Hello JohnF

I would use one RCR LiIon cell in your light and add a Flupic-board. The result would be very nice. You can use one 17640 or, after boring out the batt.-tube one 18650 cell.
In combination with the Flupic, you will get amazing runtimes on low (your choice of setting the brightness:thumbsup and incredible brightness at high level.

Best regards

____
Tom

 

[JohnF]

Yes, with the Seoul all I did was swap out the star, and focus seems great. I'm still afraid to run it until I either get a converter or properly sized resistor installed...

John F

 

[beefy6969]

Yes, with the Seoul all I did was swap out the star, and focus seems great. I'm still afraid to run it until I either get a converter or properly sized resistor installed...

John F

So whats the update on your mod? Did you get a resistor yet?

How much are resistors anyways, where can i buy some?

 

[ronzor]

i used the original resistor from the golston rechargeble
didnt fit a washer,just focused the head with some loctite.
its really a 5 minute job..
can run it until it goes dimmerwithout the heating up as the original star did.

greets