Thrunite TN32 Problem

I just received my new Thrunite TN32 yesterday and note what appears to be a design or construction problem with the battery holder. Even with the battery holder springs fully depressed the maximum length batteries I can get into it are only cells 68.4mm long or shorter. This is a considerable limitation as the average protected cell is 68.8mm long and many are longer. So far Tenergy 2600 mAh and Soshine 3400 mAh cells are the only protected ones I have found that fit and even the Soshine batteries are a snug fit.

Is this normal for the Thrunite battery carrier or do I have a defective one? Anyone have any suggestions for modifying the carrier to improve things?

Richwouldnt said:

I just received my new Thrunite TN32 yesterday and note what appears to be a design or construction problem with the battery holder. Even with the battery holder springs fully depressed the maximum length batteries I can get into it are only cells 68.4mm long or shorter. This is a considerable limitation as the average protected cell is 68.8mm long and many are longer. So far Tenergy 2600 mAh and Soshine 3400 mAh cells are the only protected ones I have found that fit and even the Soshine batteries are a snug fit.

Is this normal for the Thrunite battery carrier or do I have a defective one? Anyone have any suggestions for modifying the carrier to improve things?

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I can fit NCR 3400mAh 18650 in mine and they are 69.35mm. I do not know if yours is defective but it appears to be smaller.

Soshine are pretty good batteries,,,,,,Maybe you will have to continue using them?

EDIT: Eagletac and AW protected are even shorter than Soshine. I would stick w/ Soshine being that they are cheaper. 2/$20 at IS,,,,,,,Probably where you got them!

Capolini said:

Can't beat that deal!! $8.50/each plus free shipping! I am getting close to getting some Soshines for them!

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Actually, you CAN beat that deal right now. Illumination Supply is having a relaunch discount...if you buy 12 cells, with super saver shipping, and the coupon code, it will cost you $84.94 shipped. FOR 12 CELLS (comes out to $7.08 each). If you need 'em, now is the time!

I got it!! That was when the batteries were on sale for about $17.95/pair.Code is valid now!

Time to go,the Husky is howling!!

What with their redoing their web site maybe someone goofed but I stuck the code in at checkout and got the 15%.:thumbsup: The only thing on this order was the Soshine batteries and they sent shipping notification within 90 minutes so I should see them Monday.!!! I am certainly NOT complaining. The cheapest I have found for the Eagletac 3400 mAh 18650s is $17.50 each. I still may get three for the light depending on what ThruNite says. Sorry I missed the discount you found! IMO still a damn good price.

The really DUMB thing to me is that BOTH my name brand lights that use a 3 battery 18650 carrier have battery dimension limitations. The ThruNite has length limitations and the Jetbeam RRT-3 has diameter limitations due to the body interior diameter being a bit on the tight side. IMO BOTH are crappy design or QA problems and my background was computer electronics in the Navy and manufacturing QA and reliability testing for a division of Xerox for quite a few years in Silicon Valley. To me there is NO EXCUSE for this kind of stupid engineering on products which are in worldwide distribution. Someone(s) apparently have a hemmoroidal unconcerned outlook on manufacturing quality products that are as compatible as possible with required supply products from other makers.

Agree Rich,the carrier should have been designed better or a set spec(if some do fit longer cells). I dont have the tn32,i have the tn35vn so presume same carrier inside,except mine has been modded by vinh(extra cable soldered) This limits it more but with the nature of the light i went for IMR cells which fit fine.Quite a few options,also pany PFs too at 2900mah would be a good cell to use.
This is protected KeepPower 3100 protected=no chance


This is KeepPower IMR 2100 30A


Carrier with both cells side by side

Strangely enough, today I extended the battery carrier on my TN32 by placing 4 small washers on one of the end plates. Only a 5 minute job.

Rob.

Scourie: Thanks. Looking at the construction I wondered if that was possible. I will check in my shop to see if I have some appropriate washers for the job.

On some carriers, you can snip some of the coil off to shorten it. If soldered though, you'd need to resolder ground straps/wires if present and in the place needed to snip, etc.

Turned out that I did have appropriate washers. Stainless steel washers with an I.D. of .177" or 4.5mm and a thickness of close to 1mm or .040". Used a total of 8 to shim under both end plates which should allow batteries up to 70+mm long. Installed a set of Orbtronic 3100 mAh cells and the light is working fine. Simple job but work in a location and with a surface cover which prevents hardware from rolling away. BTW I found during disassembly that one of the center bolts on the carrier, the ones with the odd heads for inner spring contact, was not even finger tight. Might be worthwhile checking this on all ThruNite battery carriers.

The washers I used just fit on the turned down ends of the carrier shafts but are not a press or interference fit. Minimal slop though and just thin enough to allow the turned down shaft end to engage the hole in the PCB enough so once everything is screwed together there is no movement possible for the spacer shafts.

Update. I contacted Thrunite USA support and they say that they are sending me a new battery holder. They also asked for a link to this thread which I provided so that they may be responding here. Thanks for the photos Ven. They clearly illustrate the problem.

Thats good news,no problem at all,but the pic of mine shows a mod by vinh ,however in general the carrier does need to be taller mod or no mod(cable soldered on spring).

David sometimes posts on CPF,over the past few months one thing i can say is Thrunite communicates very well,a lot better than other companies!

They do need to take a leaf out of Thrunites book regarding this:thumbsup:

Hopefully a carrier that fits 65-70.5mm would be very good for future tn lights that have carriers. Fenix do manage it with their,my tk75/61/51 but admittedly the longer cells are a tight fit........but they do fit.

How bout a 'link' to where you picked up the stainless steel washers......ebay, amazon, local hobby shop???????

edit: Recon these will work http://www.ebay.com/itm/Flat-Stainl...Domain_0&var=570277633455&hash=item3f315ddd86 (the 4mm ones)?

Not sure where I got them originally as they were in my washers drawer in my nuts/bolts/hardware workbench top cabinet. I have had them for years. Almost certainly originally from Eagle Hardware before Lowes bought them or from Smallparts.com before Amazon bought them.

Thrunite has also sent me a additional battery holder at no cost once I contacted them about the problem and the new one holds 69mm long batteries with no modification. Thank you Thrunite. I also suggested to them that the battery holder should be listed as a purchasable accessory.