I was looking into making an LED headlamp for use camping and other stuff. I am posting this to ask for ideas on what to use as a case/body for the headlamp. Something like an altoids case that is easily moddable but still looks good.
Also any ideas on how to make simple reflectors to focus the LED lamp.
Appreciate any help I can get.
Thank you in advance.
PVC pipe & fittings are cheap, rugged and easy to work with.
thx lyndon…thats a good idea…hadnt thought about going down that road
One substance I’ve been playing with is epoxy putty.
It comes in tubes, you cut off a bit and mash it about like plasticine, mixing the two parts like normal epoxy glue. In about 5 minutes it goes warm and very soft and you can push it into molds or around something you want to embed. In half an hour it goes hard and is fully cured overnight. You can then shape it with a file and sandpaper and it hold paint nicely and is waterproof. Use latex or rubber gloves as it smells and probably isn’t good for the skin.
For your app you can embed everything inside a blob or embed it and push the embedded blob into a mold (make sure you use grease on the mold because it is a glue.
For a more complex two part item you could make two shells and screw them together, allowing you access the electronics for fiddling.
If you have something that may need some strength (eg the head straps) you can put some fiberglass sheeting in the mash. Either use a coarse mesh sheet so epoxy can mix between the fibers or unravel it up and drill/file out the slots later.
If not for the electronics housing you can use it to mount the lens/LED together with any mounting nuts/screws, though if you are using high power LEDs rather than 5mm units you might want to mount it ontop a aluminium plate or heatsink.
With regards to reflectors, you’re probably better to get the specific type of reflector for the LED you’re using as the optics will be better designed to match. These should be available at good electronics/hobbiest shops. LED reflectors look like lenses and relay on total internal reflection to do their work.
Other than that try getting cheap Dorcy torches, their LEDs/electronics are generally rubbish (with some notable exceptions) but I’ve found their reflectors are excellent.
Phil
rgbphil:
Use latex or rubber gloves as it smells and probably isn’t good for the skin.
If it’s really epoxy, the problem with handling it is that you will develop an allergy. I didn’t take the proper precautions when I started working with epoxies, and I get a moderate reaction when I work with it now. I know people who became unable to work with it at all.
Nitrile gloves are a good protection, as long as you’re not allergic to the gloves themselves (apparently many people are).
Great ideas…where can i get some of this epoxy putty…ive worked a little with fiberglass but not on such a small scale…is this “epoxy putty” similar to the resin you use when fiberglassing?
Hi,
I just got mine down the local hardware store (Bunnings), its called Selleys Multipurpose KneadIt Polymer Repair System, if that’s any use.
It’s not really the same as fiberglassing resin as its a putty rather than a liquid. It comes in a stick with a core of what I presume is the hardner, when mashed together it activates. There is a quick window of time when it is very gooey and soft where you can add some glass to add strength.
It smell more like the 5 minute epoxy you get in the twin tubes to glue things together…and it does adhere to surfaces.
However I think that chemically these are much the same differing in their curing systems, I’ll check this out. I do consulting for a company that plays with all sorts of epoxys, resins, carbon fibre and plastics…next time I go in I’ll ask, probably after new years though.
Phil
PS: Didn’t know you could develop an allergy…will be snapping on the latex all the time from now on.
Along those lines, what about polymer clay? It’s basically silly putty that hardens when you bake it. Available at any art store.
Polymer clay may have issues with shrinkage, but that would depend on how much you’re using for your project and how critical your dimensions are.
Another product I’ve used is Alumilite, which is a 2 part quick hardening plastic. It has it’s drawbacks, though. The working time is only 90 seconds, it gets hot when it cures, and it’s very fluid. You would need some kind of temperature resistant mold to use it.
Thx everyone…i googled epoxy putty and found Lowes & Home Depot have several kinds that i can try…ill be sure to wear gloves though when im using it
If you can make the shape out of another material, you can try casting resin. Its usually clear, shrinks a bit, but is fairly easy to shape with molds.
JB Weld gets the job done. JB Quik gets the job done with instant gratification.
Here’s a helmet-mounted lamp I made for my bicycle helmet:
http://gallery.mac.com/dr2chase#100060/ … olor=black (scroll ahead for more shots of helmet)
Materials (lens, LEDs, BuckPuck) are from ledsupply. The aluminum is from a hardware store, bent to match the helmet. The LEDs (mounted on hex pucks) are soldered first, then epoxied to the aluminum, then the lenses (with a little surgery on the back to make them flat) are epoxied onto the LED bucks, with enough epoxy gooped around to keep water out. I make sure to use clamps when gluing the puck to the aluminum; I want the epoxy layer to be as thin as possible.
Note that a bike helmet gets LOTS of air circulation in normal use.
I’ve used Sculpy polymer clay for several small projects and repairs. It seems to have about a 3% shrinkage. It comes in great colors including some metallic ones. Epoxy formulations are definitely mechanically stronger.
Cheers,
Bob
Another modeling substance is shapelock. Heat it to 60C and it becomes pliable. When it cools down it gets hard but not brittle. It is structural like any high density plastic. You can paint, drill, cut, file it. I don’t believe there is any shrinkage. It molds pretty well - I’ve used it in chocolate molds to create some interesting figures. The nice thing is if you screw up, just heat it up again and give it another try. I’ve worked it with my bare hands with no ill effects.
It goes by several names. I’ve seen colored sheets as well as the more traditional pellets.
Well kkuepker, I just happen to be in the same situation after buying some ‘bits’ from http://www.dealextreme.com
notably this reflector for 4 x Cree modules http://www.dealextreme.com/details.dx/sku.1915
Although you may not be after so much light, I’m thinking the only way to keep these modules cool in a headlamp is to machine an aluminium body/heatsink. There are casings for sale, but much too expensive…
kkuepker:
I was looking into making an LED headlamp for use camping and other stuff.…