HDS Systems #23

Showngo

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I'm still in the research stage.
Vihn has a 100% success rate and only charges $20. That should be known because that's a fantastic bargain taking into account the 100% success rate.

I only have 1 HDS and the HCRI emitter has a wonderful tint.

My thought is this…use flux gel so less time is required to desolder and then reflow.
Set the small nozzle hot air station to 700 degrees so that I get in and out quickly without the heat having time to spread. I think is where people go wrong is when they use 400 degrees, requiring more time thus allowing the heat to spread. Then just pop off that dome that was the heat shield.

I have successfully done this several times with an import twisty where the driver and LED share the same board. The driver directly is under the LED.
FWIW I had Vihn do one. Zero issues with the light after.
 

kaichu dento

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Vihn has a 100% success rate and only charges $20. That should be known because that's a fantastic bargain taking into account the 100% success rate.
I had numerous LED swaps done a few years back with probably half a dozen of them on Ra or HDS lights and never a single problem. The problems don't come from the operation itself, but rather from their level of ability. One of those things that's easy for some with the skills, and disastrous for those in over their head. Henry is another one of those individuals that's very, very good at it.
 

id30209

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I'm still in the research stage.
Vihn has a 100% success rate and only charges $20. That should be known because that's a fantastic bargain taking into account the 100% success rate.

I only have 1 HDS and the HCRI emitter has a wonderful tint.

My thought is this…use flux gel so less time is required to desolder and then reflow.
Set the small nozzle hot air station to 700 degrees so that I get in and out quickly without the heat having time to spread. I think is where people go wrong is when they use 400 degrees, requiring more time thus allowing the heat to spread. Then just pop off that dome that was the heat shield.

I have successfully done this several times with an import twisty where the driver and LED share the same board. The driver directly is under the LED.
You haven't been reading Hogo's reply about this method...
It was possible swapping emitters using hot air on old models but as i found out and Hogo pointed it out, new models have components directly under the board where emitter seats.
Don't ask me how i know...
No matter how much flux gel you're using, it will be messed up and Henry is not repairing those "mistakes" anymore but charges you a full module without a tail...
 

nbp

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Was this a one-mod decision? If yes, is there any kind of documentation as to what was removed, and why? As a somewhat longtime user of this site i'd be grateful to know what the unspoken no-nos are that aren't listed in the TOS.
Moderator action is up to Mr. Ed now. He would be the one to reply regarding that question.
 

kerneldrop

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@id30209

I have been reading…but there's different degrees of warnings. There's a don't step on that landmine, and there's a hey - powerlifting is risky for overall health. He didn't state which one.

What is the procedure now? I was under the impression the mcpcb is potted and epoxied in and does not come out?

Do you mind sharing what you did and at what temps so we can learn from it?
 

id30209

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@id30209

I have been reading…but there's different degrees of warnings. There's a don't step on that landmine, and there's a hey - powerlifting is risky for overall health. He didn't state which one.

What is the procedure now? I was under the impression the mcpcb is potted and epoxied in and does not come out?

Do you mind sharing what you did and at what temps so we can learn from it?
Good old elbow grease is what i did last time and never more (successful)
Use solder wick and press iron on all 3 contact points and while doing it try to remove as much solder as you can.
You will scratch MCPCB for sure but that is the price if you want to do a swap...
Board is potted but it is soft material so it is not an issue here. Doing it without much damage to the board, that is a real challenge.

But like i said i am not doing it anymore but i am de-domming them instead. I made some tiny tools and improvised copper gasket that goes around emitter for perfect slice and not to cause damage while using pieces of blade...
 

thermal guy

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Wow. I thought the army was messed up. CPF really is a different animal nowadays 😞
 

kerneldrop

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1662157952814.png
 

Duster1671

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@kerneldrop - Do you believe the method of reflowing the LED in place has a greater chance of success than removing the LED board and reflowing on a hotplate?

My understanding is that Vinh uses the latter method with a desoldering tool.
 

kerneldrop

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What i had in mind would be something kinda like the picture here, except for only one light and a larger lip on top keeping it in place, however not enough to impede on drawing the flashlight. That way it'd be easy to just clean with some compressed air rather than having to go at it with tape, a screwdriver, and a tiny magnet.

https://www.gearuptohunt.com/resize...T_side-view.jpg?bw=1000&w=1000&bh=1000&h=1000

It may get a little annoying, but ripoff holsters is a usa holster maker that makes heavy duty nylon and other similar material holsters that have a flap. They may can replace the velcro with magnets. They do custom work and will make it to any dimension you want

 

kerneldrop

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@kerneldrop - Do you believe the method of reflowing the LED in place has a greater chance of success than removing the LED board and reflowing on a hotplate?

My understanding is that Vinh uses the latter method with a desoldering tool.

I was just under the impression the MCPCB cannot be removed.
And if that's the case then there's no other way to do the swap.

I'll post a pic of the little board and driver that I regularly use a hot air station on.

The commercial soldering people use hot-air to do just this.
I see it on my FB videos because I guess I'm a nerd and that's what pops up.
Well that and bodybuilding videos. Oh and farm videos. If you aren't getting Mike O'Hearn videos then you're doing it wrong

Just for conversation:
The fun part about reflowing....to do it the precise way requires a reflow oven that sets a temp for a specified time and that temp will change based on the parameters found in the datasheet. When you look at the datasheet the soldering pattern is very specific and the reflow rate will tell you the programming to enter into a reflow oven.

I imagine the place that does HDS reflows uses a professional machine because they do high-level work.
 
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kerneldrop

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Here's the board I have reflowed several times using a hot air station. Of course, this is not an HDS board. It's a Convoy AAA twisty

559AE994-3041-4239-A74C-C13E96BFD23E.jpeg
 

Duster1671

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I have examined the reflow guidelines found on LED datasheets. I'd expect any reputable assembly house to follow those parameters, but it's unfortunately not practical for the hobbyist.

I've considered trying to (very) roughly replicate the temp/time schedule with a hotplate and a stopwatch, but it seems like more trouble than it's worth. I just get the plate up to ~180C, wait until the solder flows such that the LED snaps to the pad, and remove from heat. No failures so far.
 

kerneldrop

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I use an electric skillet or hot air station.
Nothing fancy. It works. It hasn't not worked yet.
Only failures I've had were from shorts.
 

LRJ88

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It may get a little annoying, but ripoff holsters is a usa holster maker that makes heavy duty nylon and other similar material holsters that have a flap. They may can replace the velcro with magnets. They do custom work and will make it to any dimension you want

Thank you for the suggestion, i have holsters like that already and i've used several flashlights in them but them rubbing up and down the holster material is the issue.

I've even considered something like this just to lessen the amount of rubbing on the flashlights:

 

kerneldrop

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Thank you for the suggestion, i have holsters like that already and i've used several flashlights in them but them rubbing up and down the holster material is the issue.

All you need is a dremel to cut and sand, and some redneck. It sounds like you have everything you need to make this happen. All of mine are made for 2" gun belts but the clasp will adjust for 1" belts I think.

I've got kydex holsters made for 1" lights. You really just need to take one that's already made and cut out what you don't want, sand for smooth lines, epoxy magnets and you're done.

Or design you one made out of billet aluminum and shine like a baller.

Those are $26 off Etsy. Just gotta modify it.

3FFD1EB1-1531-4717-8739-AF36CD6C38B8.jpeg
 

LRJ88

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All you need is a dremel to cut and sand, and some redneck. It sounds like you have everything you need to make this happen. All of mine are made for 2" gun belts but the clasp will adjust for 1" belts I think.

I've got kydex holsters made for 1" lights. You really just need to take one that's already made and cut out what you don't want, sand for smooth lines, epoxy magnets and you're done.

Or design you one made out of billet aluminum and shine like a baller.

Those are $26 off Etsy. Just gotta modify it.

View attachment 31576
I've heavily considered doing that too, the main thing keeping me from doing so has been wanting to see if there's any other alternative similar to it already so i don't have to spend the very few hours free hours i have every week actually making it. A kydex or tanned leather sleeve would work wonders as long as the back is rigid enough for it, unless i go full ham and design a new holster that snaps in half to get the light out.

Sorry to have derailed the thread a bit with this, back to HDS business.
 
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