I would also like to have a small amount. There is little time before Christmas but maybe it would be possible to make a group buy?…

Steve has some for sale in this site

Agro wrote:

I would also like to have a small amount. There is little time before Christmas but maybe it would be possible to make a group buy?…

Slayer1 wrote:

Steve has some for sale in this site

Jerommel wrote:

Agro wrote:

I would also like to have a small amount. There is little time before Christmas but maybe it would be possible to make a group buy?…

+1

Slayer1 wrote:

Steve has some for sale in this site

Agro wrote:

The question is: could we get them cheaper on a GB? Most sources seem be gone. I remember seeing some UK shop though earlier this year which had good prices for large quantities but I fail to find them now…

Can try asking Steve for GB pricing.

OK, I found that supplier:
https://mindsetsonline.co.uk/shop/pressure-sensitive-conductive-rubber-p...
5-pack of 10×10×1 mm pills is $4.58 but shipping is $7.68. Not much more than a 2-pack (of unspecified size) from veleno.

I found also
http://zoflex.com/products.html
They sell sheets.
Small sheet 152×152×1 mm is $35 + $11.5 shipping.
They have also larger sheets (304×304), 3 different thicknesses (0.5, 1, 1.5 mm), 2 hardness choices.

The Valeno designs pill will most likely be 4mm x 4mm.

That’s a really good deal for the mindsets 10mm pills if the material has the same or better properties to the usual QTC stuff.

I gotta ask… what exactly do you use this stuff for?

Mike C wrote:

I gotta ask... what exactly do you use this stuff for?

If I remember correctly, you can make an infinitely variable output flashlight with it, but sadly, QTC isn't very durable.

BLF member Match used QTC years ago in one of his threads.

http://budgetlightforum.com/node/48045

There are a few light makers that produce QTC flashlights:

• Veleno
• Peak
• Fraz
• I’ve seen a rumour that Acebeam 10160 uses QTC to

Myself I love QTC, it’s extremely simple and works great. I like this from-firefly-to-turbo adjustment better than any non-e-switch UI. And e-switches come with a few issues of their own, especially if one wants a really small light.

Thanks guys. Cool stuff indeed. It’s the first time I’ve seen/heard of it. I can certainly see the appeal of it, at least for lights using batteries that don’t have over-discharge issues.

I was interested so a little more googling shows that “Velostat pressure sensitive conductive sheet” is available from many places such as Tinkersphere $3.99 for 12” × 12” piece. Same stuff available directly from Adafruit, Digikey or Amazon for slightly more. Same properties as QTC???

As I remember from Match the only hitch in using this was getting it to stay at one setting. Need some kind of detent to hold the pressure steady.

Great, now you’ve got me wondering what I can do with Indium Tin Oxide Coated PET Plastic

It’s only 0.1 mm thick…

Isn’t this possible to make yourself?
I mean like a piece of plastic sponge, soaked with graphite and latex mixture or something?
(i guess i should try that myself ?)

It is difficult enough to get the factory stuff working properly.

So, i guess that’s a no then..

Not at all, you might make something revolutionary, but, more likely, just get a sore head trying

I’ve played around with QTC a fair bit and never got it performing 100% to my liking but it can be useful for smaller builds. I might have another go.

Yeah I cant see how the velostat sheet would work for us being so thin, not compressible?
Didn’t look into it.

I tried some QTC and then gave it away because afaict it only works in single mode lights that are battery crushers (no spring above or below the battery).

I do not own any battery crusher lights…
All my lights have a spring, so the QTC would not work.

CRX wrote:

Not at all, you might make something revolutionary, but, more likely, just get a sore head trying

I’ve played around with QTC a fair bit and never got it performing 100% to my liking but it can be useful for smaller builds. I might have another go.

Yeah I cant see how the velostat sheet would work for us being so thin, not compressible?
Didn’t look into it.

jon_slider wrote:

I tried some QTC and then gave it away because afaict it only works in single mode lights that are battery crushers (no spring above or below the battery).

I do not own any battery crusher lights…
All my lights have a spring, so the QTC would not work.

I’ve tried qtc before. I prefer the reliability and feel of infinitely variable control rings but those lights are bigger than qtc lights. I would like to try making a non-battery crush qtc host one day, just for the challenge of it

I did that with a cooyoo 10180 light.
Separate battery compartment, the head twisted to compress the QTC pill onto a fixed stationary contact not the cell itself.

CRX wrote:

I did that with a cooyoo 10180 light.
Separate battery compartment, the head twisted to compress the QTC pill onto a fixed stationary contact not the cell itself.

I wouldn’t have mentioned it otherwise

Yeah, I mean the light was stripped & heavily modified, just remembered it with pinks comment.
A slightly better way to implement QTC.
So you could have a sprung cell compartment and just the head or tail unit doing the variable thing without crushing the cell.

Found an old pic.

Jerommel wrote:

And did it work?

I tried it with a stock 10180 light

they have a 2 mode switch in the head, that is based on a domed metal disc that gets compressed to access the 2nd mode.

That defeated the QTC, which I wanted to use to get a moonlight mode.. Instead the QTC would trigger the high mode. iow, the QTC needed more pressure to work, than the 2 mode switch, which is based on a springy piece of metal that would move with less pressure than the QTC needed..

waste of time

That is not to say that a heavily modified light could not be made… but the QTC definitely did not work for my intended purpose with a 10180 light.. They come in many brands, they all work the same 2 mode spring switch..

I also tried it in a Fenix E01 and a Maratac, again hoping to create a sublument mode.. Total Fail

Yeah, i replaced the springy triangular(ish) disc in mine for a tiny strip of metal.
Works much better, because that springy disc couldn’t be soldered properly to the PCB, causing problems…
And so the tiny strip will have to be removed again if i want to try a pressure sensitive resistor in stead.
I think it’s wise to sandwich the pressure sensitive medium between thin brass sheet discs or between the PCB and a thin disc, so it won’t deform or damage.

Also can put the QTC in the tail to avoid torsional stress, some of the better mods I did that way.