LEDgardener

Cheap alternatives to heat-sinks are a subject that keeps coming up on the forum. Perhaps it would be good to have a place to post whenever something comes a long.

I imagine many links will be to websites in strange languages, mine certainly will, so I will try to give some explanation to help understand what it is, incase someone is inspired and tries to find similar objects in their location.

A local industrial supplier has this extrusion available in various sizes and strengths. It gets expensive in thicker models but this is pretty damn cheap for an extrusion that could hold two double strips or 4 rows of single line strip.

https://www.finnparttia.fi/epages/finnp ... cts/VRK120

Google translates it to 'lighting suspension rail' and the shops description says its for attaching lights, furniture or cables in an industrial environment.

I might go and grab 6m of this to test it out.

Here is the page with different sizes:
https://www.finnparttia.fi/epages/finnp ... lumiiniset

This is a 120cm aluminium reflector for a t5 style light. Seems the bottom is flat. It could be flipped so the reflectors become heatsink fins.
This one is made locally, I think these should be available much cheaper then this.

https://www.finnparttia.fi/epages/finnp ... cts/EH36LV

Great idea for a thread! Especially with the recent tariffs imposed on aluminum, it's very timely.

My solution is sheet metal.

If one is running strips for peak efficiency (generally 1/2 the maximum rated current), a heatsink is hardly necessary - all thats required is a substrate to fix the strip to (fixture).

I started repurposing old fluorescent fixtures by ripping out the guts and mechanically fastening led strips to them. Works.

More recently I have been working on some custom fixtures, and decided to try aluminum. What I have found when comparing materials in my environment (25-30°C), unless the temperature of the diode exceeds 50°C, there is no measurable thermal benefit to aluminum heatsinks. It all depends on the situation though, if you rely on supplemental heating (or are growing in a basement for example), fat heatsinks will allow one to run the diodes hotter and actively heat the space (though it will do little for the root temp)

This is about $4 of aluminum flashing and 8 rivets. Available at any hardware store.
That's a 560mm Vesta on there. If you are smart and buy a 50m roll of flashing from a national wholesaler, it should be closer to $1/ft.

I was tricky and siliconed the seams, now I can put ~3L of water into fixture which adds mass for the heatsink and creates bonus humidity. Again, could use steel, but I wanted corrosion resistance, and brushed aluminum looks pretty nice straight up - no finishing required (after deburring, that is!)

I'm happy to post a how to if there is interest. Due to the high cost of aluminum, I'm thinking of offering this as an artisan product, I believe there is a niche, but cartage could be a real killer.

In Canada its good to check places websites like Kijiji. I picked up 2x2x0.188 aluminum angle or $3/ft. Home depot has 2x2x0.063 for $7.22/ft.

Small closet grows - old aluminum tool boxes - cheap and lots of surface area to work with. Add a few stips, drill holes in the lid you can put the driver inside and hide the wiring.

Tonneau covers, trailers, roof sheeting, headache racks, bumpers, quad ramps, shelving units re-purposed.

Old bent up aluminum ladders, cut out the channel real easy with jig saw.

Waiting for a square framed truck bed extender - would work great for overhead and side lighting.

Restore is a store where people donate unwanted items which then get sold for the Habitat for Humanity organization. I've seen flashing, light fixtures like what ATP posted and other flat aluminum odds and ends.

If your heat sink doesn't need to be very thick then aluminum gutter would work, would need to buff off paint and attach strip, lots of surface area to work with. Works out to be $1.50/ft.

https://www.homedepot.ca/product/peak-p ... 1000678358

And lastly these things:
https://www.ebay.ca/itm/100-4-ft-Alumin ... 0555056756

Could do a water cooled system (yikes should I even mention this). Comes in at $0.5/ft

Could do another train of thought as above on copper, its roughly 60% better than aluminum at conducting heat, if you can find it cheap enough, its like gold.

Salvage yards are a great tip - for anyone in the BC lower mainland, ABC Traders in Richmond is fantastic. I would often go there looking for some box tube or stainless pipe, and leave with a bunch of decommissioned aircraft parts along with whatever was on my shopping list. Basically Aluminum heaven.

Awesome! Nice ideas flowing in!

Since last night I started looking at old fluorescent fixtures, which are really cheap and some would seem to have potential for refitting.

I've been looking at the options and think I will grab a bunch and benchmark what I can put together in a given time. There's a dude selling 19 fixtures @ 10e a piece, and I think he would give me a good deal for the lot. The lights are 60x60cm, and weigh 3kg a piece. These have the drivers and wires hidden which should help in achieving a clean build.

I think I'll start a 'competing with alibaba cheap leds' thread

i almost decided to use a cheap T aluminium profile, but then i started googling and found out that "sliding door aluminium track" have a lot of profiles and thickness.

as i live in brazil, here is a catalog from a brazilian supplier: http://alusupra.com.br/images/alusupra-catperf23119.pdf
take a look at the profiles listed after page 10 or 11....

off course that not all profiles are in stock, but the most common are cheap and much better than U L or T profiles.

cheers!

Iv built a couple small fluorescent retrofits using 2ft 4 bulb t5 fixtures.
What I liked most about these builds was how I was able to integrate fans into the fixture.
Cut a couple squares out of both ends so the fans push and pull.
45mm x 45mm fans did the job perfectly and were virtually silent. Just a few CFM does the trick and my Eb2s rose only 2deg F above ambient!

Currently modifying a 4x2 8 bulb fixture. Cut holes for fans on all 4 sides and the top to be able to experiment with different directions of flow.
Certainly not a necessity but I’m an efficiency kinda guy so I’m always thinking of ways to increase, and building lights has become a very valuable form of anxiety and stress relief for me so I’m always tinkering.

I just got 10 of these at Habitat for Humanity for $5 total!
660 x 64 x 25mm
I’m curious what they were for?

I’ve had excellent luck at my local salvage yard. So many hunks of useless, almost worthles aluminum and steel. The scrap yard isn’t so good since they deal mostly in metal, but the salvage yard that deals mostly in parts will be glad to get rid of an old rusty door or two. After some sandpaper and a little love with a blowtorch you would never guess my aluminum plates are courtesy of a GMC that got tee-boned in 95 then rotted for a couple decades.