Tofty's 10A Tailcap Switch (17 available)

Current progress:

A new batch of switches is finally available (as of the 27th of October 2014).

Each switch has been proven to handle well over 10A of continuous current and comes with two brass centre contact posts (1x 7mm, 1x 12mm). They are designed to fit into the standard S1 Solarforce tailcap, but do not fit into all of the other Solarforce tailcaps, namely the ones with the stainless steel rings on them.

The price is $25 for the first switch, then $20 for any additional switches, international shipping included (17 switches available).

Please PM me for my paypal address.


Hi All,

I suspect i already know the answer to this question but if somebody knows differently then here's where i will find them.

I'm looking for a forward or reverse mechanical clicky switch that can deal with reasonably high currents (4A+ hopefully) that would fit into a C/M/P/Z tail cavity and be no taller than a McClicky switch.

It doesn't have to be the conventional flashlight switch shape or have the electrical inputs and outputs in the expected positions, just meet the above requirements.

Dismantle-ability would be a bonus.

I'll explain:

I've been designing a QTC system and the design i decided upon puts so much compressive force on the top of the McClicky switch i was using that it started to fail.The solution is to isolate the switch from this force but i'm quickly running out of room and the increase in complexity and cost is something i'd rather avoid, so starting again with a different switch design might be beneficial.

I've done the obvious searches on DX, KD and FT only to find the usual suspects, hopefully someone knows of a much better alternative.


I remember Old-Lumens did some modding with a different switch, Judco:

would that work?

Thanks for the link ohaya, that switch has a lot of potential.

Old-Lumens' thread gave so much information that i'm now so confident it's what i'm after that i've just ordered a load of them from Digikey. (the only bit of information missing is whether the switch is a forward or reverse clicky, from what i can see i'm assuming reverse)

Although the switch is too large in it's standard form, the internal clicky ratchet and plunger are just what i'm after. Thanks to the magic of 3D printing i reckon i can just throw away the original plastic switch shell, make a new round one and along with some new copper positive and negative plates, make a completely new switch about the size of a McClicky or at least the slightly larger size of the Solarforce switch assy. Either way it should be an advantageous 10A switch system, much better than the alternatives......hopefully.

Now this is the interesting bit, who would want a 10A solarforce tailcap for say $25? (guesstimation)

If it's doable i can offer such a thing for sale, i'm sure there is a demand for such a thing as some of the builds on here are testament to.

Please post here to show a non-obligated interested in the idea.


The Judco can be cut down to make a square switch instead of rectangular. I did it to make it fit in a tail cap where I did not have room for the full sized switch. Glad someone found the thread. I never would have. Forward or reverse clicky? Reverse

prepare for a shock when the shipping comes through on those judcos……

I think I paid a tenner for ten and got hit for 40 quid shipping…….

they did get here in a couple of days lol but I burnt that reciept pretty damned quick I can tell you

I would definitely be in for 1, so far I've killed 4 switches with my 7 XM-L P60. (I've been considering trying to do my own fet based switch, but this would be easier)

I believe I might need one, or two, or possibly 3. :slight_smile:

Nice work, good to see someone thinking outside the box. Inside the boot? At the bottom of the tube? Ok, it’s late…

Thanks for the information Old-Lumens, alas i doubt this build can use the original Judco plastic housing and will require a complete new plastic body to increase it's strength and ensure a perfect fit into the Solarforce S1 tailcap. I'm hoping that this complete redesign will allow me to add the positive and negative connections exactly where they're needed. The switch should also be simple to install and remove as it will be retained by the original aluminium retaining ring from the Solarforce tailcap.

Hi Gords, i ordered quite a lot of these switches, enough to get free shipping although i'm sure i'll still get stung with high customs charges (edit: just got delivered while typing believe it or not, £15 customs charge). If this project goes well i suspect i really won't regret having more switches than i originally planned on. Had i not learned about the Judco switch the alternative would have been to try and modify the McClicky switch which costs 5 times that of the Judco (less than $1.50 each delivered).

Hi scaru, The FET type switch is a good idea for high currents, it's just a shame only one person has ever sold such a thing, it turned out not to be particularly reliable and was never developed further. If my switch works properly it should be perfectly suitable for your application (if anything i will be increasing it's current handling above 10A by using slightly thicker copper for the leads).

Do you have a link to your 7xXM-L drop-in build? I remember seeing the MCPCB diagram of it a while ago but haven't seen it in the flesh as it were.

Thanks for showing an interest Dale, fortunately from the preliminary modelling of the switch that i've done so far it looks like there is enough room for everything and this might just work.

I would like at least one. Now what about 9 amp driver that would fit in a P-60, who has a lead on that to accompany the high amp l tail?

Thanks scottyhazzard, a 17mm 9A driver would be a really nice addition to this switch, great for an MT-G setup. Step forth those up for the challenge.


Modelling finished for the first prototype of the switch shell and order placed with Shapeways for a few examples (to be delivered in a couple of weeks hopefully).

The positive brass plate is there just because it suits my requirements, a spring can be easily substituted into it's place.

15 pound customs charge isn’t bad if you got hit for the 8 pound daylight rob….I mean handling charge :expressionless:

that one always bugs me. The model looks great, whats the od of the housing if you don’t mind answering? I could happily replace a few poor quality switches with these, even if I don’t need the 10a capability

I agree, any system that charges you for the unwanted service of collecting unnecessary tax needs to be challenged. However the parcel arrived via UPS rather than royal mail and their charges must be different (read fairer).

The OD is 21mm, because i need the switch to be strong i've made it to fill all the available space in the S1 tailcap, therefore the switch is quite over-engineered and could be made smaller as soon as it has been proven to work. It's possible that it could be made the same size as a McClicky, the Surefire clicky e-series switch or something else even smaller perhaps.

Great idea. Best wishes on success. Based on how reasonable your prices are on your other stuff, I think your switch or switches will be in high demand.

im thinking of 18650 tailcaps……mostly, some 26650 tailcaps would benefit from this too.

regardless I’ll pick a couple up to play with when they become available.

the tr-j19 would definitely benefit from a 10a judco but to be fair, the tail caps that big I could probably rob the switch gear from a signaling box and it’d fit lol

I gotta say....these just look sexy

Orsm switch. It almost looks like I can pick it out of the screen its so life like.

Very nice looking. Keep up the great work.

Looks something like a ZeroRez tailcap upgrade. These are good for 20A.

ZeroRez is just a solid piece of brass. Different approach.

The design is looking good. But since its still a regular switch, I'm curious to see if it really makes any difference compared to a good regular switch.

Also, I think I remember having problems with copper oxidizing in the air and not conducting electricity that good after a while. Anyone else?^^

Thanks, i can't promise a reasonable price if i make only a few of them but perhaps demand will be such that economies of scale can come into effect. Too many parts that i will have to hand make at the moment.

Any light that takes an 18650 or larger should have room for this switch, or as you say something impressively industrial.

Thanks Matt, i still think a FET switch would be a good idea but this switch has turned out to be relatively simple, although my design hasn't been proven to work yet.

Thanks a lot, if i can make to copper and brass pieces to look that good i'll be pretty chuffed.

Thanks, the order from Shapeways should be completed in about a week, then i should be able to assemble everything for a prototype. I've already thought of a few changes that will be made to the next switch version though.

The ZeroRez is a twisty/momentary upgrade to the original Z41 tailcap, this switch is a clicky upgrade like the McClicky switch. The ZeroRez is the best for high current handling, with the only improvement being making it out of copper.

Thanks, the Judco switch has had positive reviews by the modding community here and i will be increasing the contact areas on all connection points. I suspect improved current handling will be achieved and it's resistance should be lower, making it a valid upgrade in very high current lights. It's also a reverse clicky and there hasn't been a high current reverse clicky switch option before.

Copper oxidisation might be a problem but silver plating is not a costly procedure if corrosion protection is needed. The switch will be able to be dismantled so contact surfaces can be observed and cleaned if required.