Building New Panels - Sharing the Process
- Thread starter rrog
- Start date
Thanks Hemp- I was unfortunately thinking those little pads did all that - no screws. Rives pointed out that's likely not the case, and I have you confused with one of the other very helpful people here, because you've never used them.
You can't just attach the LED to the main heat sink without some smaller sink attached?
You can't just attach the LED to the main heat sink without some smaller sink attached?
You can , but it's a little more complicated, because the LED should be soldered to the heatsink for maximal thermal transfer. Every LED has at least 3 areas that must be soldered : 2 terminals (anode and cathode) and the thermal pad. If you want to bond the led directly to the heatsink you must insulate the first 2 terminals from the heatsink which makes things a little bit complicated. This is more easily done when you have a big aluminum PCB, with electrical traces printed onto it, so this is way I prefer using small 20mm (or 16mm) aluminium star PCBs.
I appreciate your patience while I get this straight in my mind. This is what I'm looking to buy. Is the star shape the heat sink you're referring to? Then either thermal epoxy or thermal grease and screws?
EDIT:
OK I get it. The star-shaped base is the heat sink that we solder leads to. I'll use a silver grease like Artic Silver 5. And screw the Sinks to the big sink with Rives Torx Screw method.
EDIT:
OK I get it. The star-shaped base is the heat sink that we solder leads to. I'll use a silver grease like Artic Silver 5. And screw the Sinks to the big sink with Rives Torx Screw method.
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If you work directly over the big main heatsink you can just use a copper wire connected to it with the other end wrapped against the cold water pipe on the kitchen, or any other metal pipe that go into the ground.
And try to wear just natural fiber clothes and avoid any nylon/polyesther fibers.
I think it requires quite a big electrostaric discharge to burn this high power LEDs, but it better to be careful.
And try to wear just natural fiber clothes and avoid any nylon/polyesther fibers.
I think it requires quite a big electrostaric discharge to burn this high power LEDs, but it better to be careful.
After the little escapade where I blew that string, I (finally) bought a grounding wrist strap. You can then get a coiled lead that stretches out, like for a telephone handset and has a snap connection to the wrist strap. I then took a 120v plug and hooked up just the ground wire, and in turn hooked this ground wire to the wrist strap lead. It allows plenty of motion and you quickly forget that you even have it on.
I don't know how old you are, but another little goody that I'm finding really helpful with geriatric eyes is a headband with an led lamp built onto it. I got a Black Diamond Cosmo, and I wish that I had bought one years ago. My teeth are much happier not gripping a Mini-Maglite.
I don't know how old you are, but another little goody that I'm finding really helpful with geriatric eyes is a headband with an led lamp built onto it. I got a Black Diamond Cosmo, and I wish that I had bought one years ago. My teeth are much happier not gripping a Mini-Maglite.
Holy crap - The mini-mag in the teeth. I carry one in my pocket constantly. Just ordered the Cosmo. I've been wondering about such a thing for a while and if it's good for you I'm sold.
Love the idea of just plugging into the ground only. Very clever, Mr. Rives. Simple.
Should I look at a rubber mat? I have several different vinyl mats, actually.
These are all very helpful and practical tips. Thank you.
I have been envious of those chisel / bevel tips on the soldering iron. That's huge surface area for pre-tinning the LEDs. They don't seem to offer that tip for my little Weller. I have a screwdrifer tip with e small bevels. I wonder if that's a beneficial enough tip that I should look at another soldering iron.
Love the idea of just plugging into the ground only. Very clever, Mr. Rives. Simple.
Should I look at a rubber mat? I have several different vinyl mats, actually.
These are all very helpful and practical tips. Thank you.
I have been envious of those chisel / bevel tips on the soldering iron. That's huge surface area for pre-tinning the LEDs. They don't seem to offer that tip for my little Weller. I have a screwdrifer tip with e small bevels. I wonder if that's a beneficial enough tip that I should look at another soldering iron.
Rives- regarding the attaching of the LEDs via screws, here was a neat synopsis I read elsewhere. I believe this is what you're doing:
- Drill each hole with a 7/64th drill bit
- An M3 .50 x 6MM button head machine screw will self tap itself into the 7/64th hole
- Isolate the screw head from the LED contacts with a plastic washer. Part number 16FW004032 and are only .031 thick. http://www.amazon.com/MICRO-PLASTICS-16FW004032-Washer-Nylon/dp/B00867QPH6
- Drill each hole with a 7/64th drill bit
- An M3 .50 x 6MM button head machine screw will self tap itself into the 7/64th hole
- Isolate the screw head from the LED contacts with a plastic washer. Part number 16FW004032 and are only .031 thick. http://www.amazon.com/MICRO-PLASTICS-16FW004032-Washer-Nylon/dp/B00867QPH6
If you do not intend to remove the leds from the main heatsink to soon I think is more simple to use a thermal glue (found some cheapo thermal plaster on Ebay - http://www.ebay.com/itm/Thermal-Con...er-Adhesive-Compound-For-PC-GPU-/170921878892) . LEDs are not CPUs so an average thermal glue will do the job pretty well , as long you don't have to many air bubbles trapped between star heatsink and the main heatsink. This kind of plaster (silicon based) ensure enough bond to keep the LEDs in place, but they could be removed later with a sharp knife. If you use epoxy thermal resin it might be extremely hard or even impossible to remove the LEDs from the heatsink .
I glued my LEDs to the heatsinks just with thermal white paste and to drops of universal rubber glue on opposite edges of star heatsinks. For the next project I will use thermal plaster.
I glued my LEDs to the heatsinks just with thermal white paste and to drops of universal rubber glue on opposite edges of star heatsinks. For the next project I will use thermal plaster.
Rrog, that's basically what I do, but I use SAE sizes rather than metric. I use #4x3/8" self-tapping screws, a #42 numerical drill bit, and the insulating washers.
If you go this route, I would buy several extra drill bits and a couple of extra T-10 Torx drivers. Amazon has the drivers for a couple of bucks, and the Torx setup works the best that I've found for retaining the screw and getting enough torque on it to thread the hole. Try and lay out the holes so that they fall between the fins on the heatsink - if you partially catch a fin while drilling, it will snap the drill bit in a heartbeat.
I epoxied one project, and have used the screws since then. I don't think that the epoxy transmits the heat quite as well as a thermal compound like Arctic Silver, and I've found the screws are a very easy system to modify later.
screws - http://www.mcmaster.com/#90925A108
If you go this route, I would buy several extra drill bits and a couple of extra T-10 Torx drivers. Amazon has the drivers for a couple of bucks, and the Torx setup works the best that I've found for retaining the screw and getting enough torque on it to thread the hole. Try and lay out the holes so that they fall between the fins on the heatsink - if you partially catch a fin while drilling, it will snap the drill bit in a heartbeat.
I epoxied one project, and have used the screws since then. I don't think that the epoxy transmits the heat quite as well as a thermal compound like Arctic Silver, and I've found the screws are a very easy system to modify later.
screws - http://www.mcmaster.com/#90925A108
Hempfield- I've seen a few videos where this adhesive was used on the heatsink. Is there a general comparison of heat conduction with the grease vs the "silicon plaster?"
If I did this, I'd want the highest rated product, if there is such a thing.
Thank you for this suggestion.
EDIT:
I posted this before I saw Rives' post. So Rives- you think the conduction suffers a bit with the glue. Sure does make it easy... mighty compelling...
If I did this, I'd want the highest rated product, if there is such a thing.
Thank you for this suggestion.
EDIT:
I posted this before I saw Rives' post. So Rives- you think the conduction suffers a bit with the glue. Sure does make it easy... mighty compelling...
I found that it wasn't as easy to use the adhesive as you might think. The mcpcb needs to be pushed down tight, and preferably held for a bit to eliminate the chance of it lifting a little. I used the "permanent" stuff, and freaked out when I blew that string - however, the adhesive was no match for a sharp chisel and a small ball-pein hammer. With the way that I am currently swapping things around to experiment with different spectra, I wouldn't even consider the adhesive.
I think that it also greatly simplifies soldering the leads on - I just back the screws off a couple of turns, slip a popsicle stick under the star to keep the heat from being sucked away, and solder the connections. If the stars are attached to the sink, it's a bitch to get things warm enough (those damn heatsinks work!), and since I use a template to locate my chips, it would be very difficult to solder the wires first.
I think that it also greatly simplifies soldering the leads on - I just back the screws off a couple of turns, slip a popsicle stick under the star to keep the heat from being sucked away, and solder the connections. If the stars are attached to the sink, it's a bitch to get things warm enough (those damn heatsinks work!), and since I use a template to locate my chips, it would be very difficult to solder the wires first.
tenthirty
Member
Don't want to be considered spam, but I found this site that have various XM-L LEDs on 20mm and 16mm star PCB :
http://www.fasttech.com/products/1609/10001903/1189702
Available models and parts:
Cree XM-L T4-7C 2800-3000K White LED Emitter with 16mm Base
T4-7C: 16mm: $5.12
Cree XM-L T4-7C 3000K White LED Emitter with 20mm Star Base
T4-7C: 20mm Star: $6.51
Cree XM-L T5-5C1 / 4000K Neutral White LED Emitter with 16mm Base
T5-5C1: 16mm: $6.90
Cree XM-L T5-5C1 4000K Neutral White LED Emitter with 20mm Star
T5-5C1: 20mm Star: $6.91
Cree XM-L T6-1A 7000K White LED Emitter with 16mm Base
T6-1A: 16mm: $3.81
Cree XM-L T6-1A 7000K White LED Emitter with 20mm Star Base
T6-1A: 20mm Star: $3.82
Cree XM-L T6-3C 5000K White LED Emitter with 16mm Base
T6-3C: 16mm: $4.51
Cree XM-L T6-3C 5000K White LED Emitter with 20mm Star Base
T6-3C: 20mm Star: $4.52
Cree XM-L T6-4C 4300-4500K 943-Lumen White LED Emitter on 16mm Base
T6-4C: 16mm: $6.38
Cree XM-L T6-4C 4300-4500K 943-Lumen White LED Emitter on 20mm Star
T6-4C: 20mm Star: $6.39
CREE XM-L White LED Emitter with 16mm Base
U2-1A: 16mm: $4.11
CREE XM-L White LED Emitter with 20mm Star
U2-1A: 20mm Star: $4.12
CREE XM-L White LED Emitter with 16mm Base
U2-1B: 16mm: $4.11
CREE XM-L White LED Emitter with 20mm Star
U2-1B: 20mm Star: $4.29
Cree XM-L U2-2C 5300-5700K 950-Lumen White LED Emitter on 20mm Star
U2-2C: 20mm Star: $4.71
Cree XM-L U3-1C 6000-6500K 1100-Lumen White LED Emitter on 16mm Base
U3-1C: 16mm: $5.16
Cree XM-L U3-1C 6000-6500K 1100-Lumen White LED Emitter on 20mm Star
U3-1C: 20mm Star: $4.92
http://www.fasttech.com/products/1609/10001903/1189702
Available models and parts:
Cree XM-L T4-7C 2800-3000K White LED Emitter with 16mm Base
T4-7C: 16mm: $5.12
Cree XM-L T4-7C 3000K White LED Emitter with 20mm Star Base
T4-7C: 20mm Star: $6.51
Cree XM-L T5-5C1 / 4000K Neutral White LED Emitter with 16mm Base
T5-5C1: 16mm: $6.90
Cree XM-L T5-5C1 4000K Neutral White LED Emitter with 20mm Star
T5-5C1: 20mm Star: $6.91
Cree XM-L T6-1A 7000K White LED Emitter with 16mm Base
T6-1A: 16mm: $3.81
Cree XM-L T6-1A 7000K White LED Emitter with 20mm Star Base
T6-1A: 20mm Star: $3.82
Cree XM-L T6-3C 5000K White LED Emitter with 16mm Base
T6-3C: 16mm: $4.51
Cree XM-L T6-3C 5000K White LED Emitter with 20mm Star Base
T6-3C: 20mm Star: $4.52
Cree XM-L T6-4C 4300-4500K 943-Lumen White LED Emitter on 16mm Base
T6-4C: 16mm: $6.38
Cree XM-L T6-4C 4300-4500K 943-Lumen White LED Emitter on 20mm Star
T6-4C: 20mm Star: $6.39
CREE XM-L White LED Emitter with 16mm Base
U2-1A: 16mm: $4.11
CREE XM-L White LED Emitter with 20mm Star
U2-1A: 20mm Star: $4.12
CREE XM-L White LED Emitter with 16mm Base
U2-1B: 16mm: $4.11
CREE XM-L White LED Emitter with 20mm Star
U2-1B: 20mm Star: $4.29
Cree XM-L U2-2C 5300-5700K 950-Lumen White LED Emitter on 20mm Star
U2-2C: 20mm Star: $4.71
Cree XM-L U3-1C 6000-6500K 1100-Lumen White LED Emitter on 16mm Base
U3-1C: 16mm: $5.16
Cree XM-L U3-1C 6000-6500K 1100-Lumen White LED Emitter on 20mm Star
U3-1C: 20mm Star: $4.92
Look what I received in the mail today : 10x XM-L T6 U3
I have to wait for driver, voltmeter and ammeter to arrive and the building process will begin.
https://www.icmag.com/ic/album.php?albumid=41610&pictureid=1006899View Image https://www.icmag.com/ic/album.php?albumid=41610&pictureid=1006901View Image https://www.icmag.com/ic/album.php?albumid=41610&pictureid=1006900View Image
Awesome. The left picture is the shape (Merkaba) that you want
