What did you mod today?

It really looks beautiful with this worn ano and blue blue switch. It reminds me on my beloved 602c triple 219a. It was my favourite light to this date!
I would love to get one of this host for a new build but can’t find one anywhere. Especially blank like yours.

I know the feeling of failure/dissatisfaction/disappointment of mod or build. It really hurts :cry:

Looking great djozz :sunglasses:

Not sure if there is one.

I’m still new to 3D printing, I only have printer for 2 weeks.

This light is similar but quite a bit smaller even than the 602C. It was for sale for 8 dollar at Fasttech for some time and then disappeared. I modded one for myself and gave one away. Of course it can not soak up a lot of heat before overheating, but with some hand-sinking it can maintain 300 lumen.

Hmm you are right, there is not much, here one store: https://shop.3dfilaprint.com/filaprint-pet-g-black-transparent-175mm-3d-printer-filament-10939-p.asp but the example does not look transparent.

I installed the $5-ish BLF driver from banggood in my Ultrafire C8. I put a smear of eBay thermal schmoo on the pill and so far, so good. I have been going lightly with the Turbo mode since I already burned up a LED in a zoomie that way, but the LED board wasn’t seated well and no thermal paste. I also sliced the dome, but the finish was VERY poor. This is the first mod that has made me giggle after testing it out. Moonlight, long-press in to Turbo, very nice! It is really not much, but it is mine, etc…

That sounds like great result!

There is only a short list of things to take care of to make a flashlight with great output (right led, DTP copper board, good thermal connection to the host, low resistances in the electrical path, high drain battery). Unfortunately (or fortunately :sunglasses: ) chinese budget manufacturers usually fail in in one or many items in the list, which gives us things to do and be awesome :smiley:

Thanks djozz, I was a little discouraged after burning up the previous LED, and the answers I received in the “No Stupid Questions” thread, but I bought a helping hand cheap at a model train show on the weekend, and this was a project in need of soldering. I really should order a nicer copper PCB and LED before I burn this one up, hmmm…

^ So your sliced XM-L2 is not sitting on a copper DTP-board? It is very probable then that the led will burn up at some point. Copper DTP-boards make all the difference in the world in heatsinking, and are cheap nowadays. It requires the skill to reflow the leds yourself but to learn to do that is not really hard, especially with all the information about it floating around on BLF.

If anyone has a 3D printer and want to print Convoy S2+ black metal button copy, here is the file: Convoy S2+ metal button replacement for lighted tail cap. by Sp4wN - Thingiverse
Had to wait 24 hours after registering.

Thank you, I might try it :slight_smile:

A friend asked me to rebuild a wurth cordless drill battery pack for him. After disassembling the battery pack (5S2P configuration) I found out that all batteries were 0.01V and there is a very simple charging module managing that pack. No balancing wires, just positive and negative contacts with small double black wire stuck between battery cells (maybe some kind of sensor wire).
This doesn’t look like a safe way to charge a 5S2P battery pack. Please advise, I’m having second thoughts about proceeding with this rebuild.

This scheme works in many makita battery packs for years. I like it much more than other brand packs (like aeg or fein) that have various balancing wires and extra lvp which usually causes cells disbalancing.
Just use brand cells (Im using 20R or 25R) and original charger.

P.S. I suppose pcb is aftermarket and was copied from the 5S1P original board, but I dont think this is a problem.

Besides the + and - contact there seems to be a temp-sensor.

For my last Battery-Pack mod: I use the original charger, but it has 2,2A charging current and a time limitation. That means it charges only one hour or little above. That means I have to charge my new Battery-Pack with Samsung 30Q two times to charge it to 20,6-20,8V Charging Limit. That equals 4,12V - 4,16V for each single cell Thats perfect.

For the battery-pack of your friend, you have to try afterwards, if you have to charge it two times, or if the charger carges to a definitive stop voltage.
What cells do you found in this battery-pack and how old is it?

Agreed on all points djozz. Money for hobbies just isn’t there all-at-once, so if I can drib and drab it out over a few months all the better. In the next couple of weeks and I’ll put in an order with Cutter. Thanks djozz!

Thanks kiriba, so I suppose that this charger relies only on using a batteries from same batch, matched and with similar internal resistance.

I’ll have to test it somehow before ordering new batteries. If termination is based on time I can use only same batteries as before because drill is used in workshop with many same battery packs. To keep track this single one would be impossible. Batteries inside this pack are Samsung 18650-13L. Don’t know how old this pack is but it is few years old for sure.

For a hobby machine is good enough and , as Kiribaru said , is doing the job...But I have to disagree about protection and balancing system that it is attached to almost all the battery packs for professional machines ( heavy duty ones ,with several charging and discharging cicles per day ...) , exactly for the reason NOT to let the cells being unbalanced and spoiling the whole pack !...

Pairing the new cells before installing ( capacity and internal resistance ) would be a good path to follow...

Regarding the charger with a fixed time ( 1 hour ) charge , this could be easy modified from the internal electronics , usually is about a capacitor charged via a resistor until the voltage reaches the triggering point . Double the value of capacitor should double the charging time ...

I completely agree about balancing cells.
If charger terminates charging after, let’s say an hour, then that means you have to discharge battery pack completely before charging again. What would happen if you began to charge it when half discharged?

You can check batteries after some time of real usage. Ask to bring it discharged, check cells voltage difference and then charge and check one more time.
Complecated circuits can balance charge cells, but often kill cells by discharge one or few units witg extra lvp.

Lets clear some things about BMS ( Battery Management System) . There are 3 different types of modules used for the battery packs , as following:

Protection Modules , that are meeting the basic requirements :

Over current protection at charging & discharging ( any value from 1-100A and above , chosen by the manufacturer of the battery pack )

Over charge protection for each cell , at a max. 4.25V

Over discharge protection , at 2.9V.

Balancing Modules ,that actively stops the charging and discharging of a weaker battery from the pack, and adjust the charging current in order not to undercharge some and overcharge some others .

BMS Modules , that are combining in one, the 2 described above.

These modules are a must in the laptops and professional cordless machines , in order to expand at maximum ,the life of a battery pack.

On the other hand , for the hobby machines is accepted not to have this modules , due to the lower price and the fact that , not being heavily used , the unbalancing process will be slower .

About the chargers :

A professional one will have a feed back from the battery pack ( via 2 extra slots ) , stoping the charge process as soon as the charging current is dropping under a certain value.

A hobby charger is likely to have a timer for charging process due to the fact that is missing the feed back , and as a protection measure. For this particular type is more likely to get an incomplete or overcharged battery pack

As a simple rule : if you have a battery pack with all 5 slots populated with connections ( not only 3 like , like in your case ) , and the charger with the same number of slots connected to the internal PCB , there is a good chance to have a reliable charger and a protected and balanced battery pack .

But , most of the time , the price will tell you what you paid for...

Discharging completely a li-ion pack is not a must , by contrary , only the Ni-Cd ones has to be like that , due to the well known memory effect of those .

In your particular case I have to ask you one question : does your charger have some indication about the charging process ( ex. red led = charging , green led=fully charged ) or something else ? Even on the cheapest chargers an indication of this type is present !!!...