Homebrew light switch for handlebars...?

Bike Forum

Homebrew light switch for handlebars...?

13 posts & 5 voices | Started 4 months ago by Bez | Latest reply from Bez

Tags:

No tags yet.

Bez - Member

Anyone done this?

I want to build a switch that will toggle between two dynamo lights (one normal, the other angled up as a 'main' beam). This should be a simple DPST toggle switch of some sort, but it's a case of finding a switch and a mounting that aren't going to result in strapping on a box that looks like some sort of Acme bomb trigger from a Roadrunner cartoon. (If I end up with a little boxed connector away from the switch then that's fine as I can stash that in my little bar bag, or something. But I don't really want a big, bulky switch.)

In terms of attaching it, a velcro strap (as used by USE - and no, I can't just use their switch as it's a momentary switch) seems far more useful than a hacked accessory clamp, as I'll want to fit it to taped oversized bars. But I'm open to ideas.

Anyone know of any readymade switches that could be useful, or any parts? I've looked at Maplin and RS but haven't seen anything inspiring yet. I guess there isn't anything out there, but...

Posted 4 months ago #
ruscle - Member

If I were you I would visit the diy lights forum over on mtbr site as these guys produce some top notch stuff and have great ideas/understanding of these things:

http://forums.mtbr.com/lights-diy-do-yourself/

Posted 4 months ago #
Love Tubs - Member

Passing on a tip that Troutie put my way; once you've found your switch then you can create a mounting bracket that custom fits to your brake clamp as if it's a body-part! I know, coz I've done it (more on this when I've finished my hid-monster conversion). Once you've experienced thumb activation, there's no going back

.
.
.
.
Pisssst, SUGRU is your friend

Posted 4 months ago #
joemarshall - Member

USE switch or similar and a two pole latching relay (you'd need one with a single coil that switches once per pulse rather than one with two switching coils, can't rememeber what they're called).

I think motorbikes use handlebar mounted switches, and they'd have different light settings although I don't know how the wiring works, or how they mount.

Posted 4 months ago #
ruscle - Member

+1 for sugru

Posted 4 months ago #
Bez - Member

Hm, thanks. This thread has a few leads (no pun intended):
http://forums.mtbr.com/lights-diy-do-yourself/remote-switch-756940.html

Seems like there are plenty of push-to-make options around so my best bet may be to add a relay as per Joe's suggestion. Only thing with that is that I'd need to know the maximum voltage the hub's going to kick out - not too hard in theory, although to be on the safe side I'd have to be reading a patched-in multimeter whilst pasting it down my local 50mph hill

Have looked at motorbike switches but they're mostly bulky and I've not yet seen one that would have a fighting chance of being fitted to an O/S road bar.

Posted 4 months ago #
joemarshall - Member

Only thing with that is that I'd need to know the maximum voltage the hub's going to kick out - not too hard in theory, although to be on the safe side I'd have to be reading a patched-in multimeter whilst pasting it down my local 50mph hill

Zener diode? It isn't like you're worrying about efficiency of this circuit, as it's only used when the button is pushed?

It occurs to me that with a relay you'll need to be going at a certain speed before you can switch, which seems unsatisfying somehow though.

Posted 4 months ago #
Bez - Member

Neat idea...
http://forums.mtbr.com/8869542-post38.html

Posted 4 months ago #
joemarshall - Member

That looks like it might work, assuming you can get a two way toggle mini switch.

Or a crazy idea - sew one up - dunno how water resistant it'd be, or how you'd make it easy to switch, but this'd be easy to make two way.

http://www.instructables.com/id/Conductive-Velcro-Toggle-Switch/step5/Turn-on-the-juice/

Posted 4 months ago #
Bez - Member

Zener diode?

Ah. I keep coming across this phrase and need to look it up

Another option that becomes less unattractive if I'm having to build a little box of tricks anyway is to somehow wire up a basic head unit from a normal MTB light (eg a Magicshine or something) so that I can use that as the main beam. That would work better from a lighting point of view (moar of lumens, more suitable beam) but would require an additional bunch of handiwork on my part - I keep reading the phrase "bridge rectifier" (a concept I distantly recall from ye olde education years, but in pragmatic terms see previous comment for "Zener diode").

When compared to buying another Cyo and pointing it up, the upsides are the better beam and probably lower cost, but the downsides are requiring an additional mounting point and having to get more clued-up on electronics.

Spot the leccy n00b

Posted 4 months ago #
joemarshall - Member

Is it a road bike by any chance? Just that looking at a small spdt switch (bog standard maplin one), it looks like it'd stuff into the bottom of the hoods just about and could be angled to poke out inwards so it wouldn't be in the way of my hands. I don't quite know how you'd make it stick in there though - maybe just poke a hole through the rubber of the hoods and screw it onto it with some washers or something horrible like that.

Posted 4 months ago #
pdw - Member

I struggled with a very similar problem. I couldn't find any toggleable switch that could be mounted neatly, so I eventually opted to change the driver in my light so I could use a miniature push switch and let the electronics do the toggling. This can be mounted very neatly in an STI lever, using the FlightDeck nipple to operate the switch:

http://singletrackworld.com/forum/topic/bflex-driver-in-lumicycle-halogen-more-light-diy

It wouldn't take a lot of electronics to do the toggling if you want to go down that route.

Posted 4 months ago #
Bez - Member

Road bike, yeah, hence comment about fitting to road bars

That FlightDeck hack is tidy. Hmm. Need to think about what's possible and what are the factors I need to consider.

Ideally I'd like to:
- have the Cyo as my dip beam
- have a ~600 lumen symmetric-beam LED unit as the main beam
- have some sort of switch that I can access without taking my hands off the bars
- wire the switch to switch to the main beam, turning the dip off
- also wire up the USB charger I've bought

I'm thinking there's a solution involving a little plastic box with some nice plug-in connectors of some sort sticking out of it, but it's going to be a bit of a learning process to get to the point where I can draw the wiring diagram for it. Let alone then testing my shoddy fine motor skills by soldering the thing up

Posted 4 months ago #