der_wille_zur_macht
Team RC
Hello everyone,
Since my DIY LED driver thread went over so well, I thought I'd post some photos I took while building one of the nano fixtures I've done recently. Since other threads have covered the theory of these builds well, and given recipes for how to size them, etc. in this thread, I will try to concentrate on the practical steps you need to actually put one together. This will be aimed at people who are beginners (though sadly I missed the photo op for some of the crucial steps). As always, if any of the more experienced people see problems in what I'm doing, please correct me.
When I started getting excited about LEDs over the summer, I wanted to build some experimental rigs to play with a few different variables:
1) Color. I wanted to see what different combinations of LEDs looked like.
2) Control. I wanted to play with controlling LEDs with an Arduino.
3) Positioning. I wanted to experiment with different heights, angles, and positions for LED lighting, to see how easy it was to create dramatic effects.
4) LED choice in general. I wanted to get hands-on experience with all of the common LED choices: XR-E cool white, blue, and royal blue; Rebel cool white and blue, etc. Though the specs are similar, there are some subtle differences (viewing angle, plus the Rebels are available 3-up) so I wanted firsthand experience.
The fixtures in this thread were the result. I built several of these over the summer - a few of them have been running on tanks for a few months; the rest are either on my workbench or have been cannibalized for parts.
These fixtures are built with the following components each. I've done some different combinations of LEDs but this is what ultimately went into use above the tanks:
1) A DIY driver as detailed in my thread above. I built these at 350mA and 500mA. I wouldn't use this density of LEDs on such a small heatsink any higher than that. Cost: $6 in parts.
2) A big beefy CPU heatsink I got from mpja.com for like $4.
3) A mix of three-up Rebels and XR-E, such that each fixture had two of the three-up Rebels and two of the XR-E, for a total of 8 LEDs per fixture. Cost: ~6/ea for the XR-E and ~$16/ea for the three-up Rebels.
4) A stainless steel clip-lamp I got at a big discount retailer. It's sleek, and the bendy neck allows for repositioning to test different angles and heights above the water column. Cost: $9.
5) Several feet of 16 gauge lamp cord. Used for wiring from the fixture to the drivers, and drivers to power supply. Cost: $1 or $2.
6) Some 20 gauge solid core hookup wire. Cost: Practically free if you buy a big spool.
7) A 24v DC power supply. I like the ~6 or ~8A supplies from mpja.com. Cost: $15 or so.
8) A project box to hold the drivers. Cost: $5
9) Some form of dimming or control, if desired. I'll go into it in another thread. Cost will vary significantly, so I'll leave that out for now.
10) Mounting hardware. I used stainless self-threading screws and nylon washers. The washers are to keep the screws from shorting on the soldering pads on the stars. You DON'T want the heatsink live!
11) Misc. consumables - solder, heatshrink, tape, zipties, thermal paste.
12) Cooling fans - the CPU heatsinks I got came with little cooling fans that I used for this project. Any 12v fan of the correct size will work fine. It's tight quarters in these fixtures so I had to remove the stock mounting screws, cut the corners off the heatsinks, and ziptie the fans back on.
Tools I used included:
1) Assorted hand tools. A centerpunch, screwdriver, wire cutters and strippers, etc.
2) A drill. I have a drill press. A hand drill will work in a pinch, but accuracy will be hard to achieve, and you'll get fatigued doing this many holes by hand.
3) A soldering iron. It's HARD to solder the LEDs since the heatsink sucks the heat away. A nice powerful temperature-controlled soldering station will definitely help.
A small nano tank (say, under 10 gallons) would be fine with one of these fixtures. A midsize nano would probably want two (10 - 20 gallons) and a larger nano (20 - 30 gallons) would probably need three. Again though, I built these to play with LEDs, not to light tanks, so study up in the other threads before putting LEDs on a tank. I'm driving these a lot lower than most people, which changes the density (i.e. how many LEDs you might want on a tank). And, since I'm packing a bunch of LEDs into a small area, these fixtures create more of a spotlight effect than other LED builds - this can create some really cool effects but you'll be disappointed if you want a homogeneous distribution of light.
Ok, let's get started.
First, I laid out the stars on the heatsinks and marked the mounting holes. I used a centerpunch because it makes a convenient divot to drill in. Don't try drilling on a pencil mark, the bit will wander and the hole will not be correctly located. Get a centerpunch if you don't have one.
When laying out, keep in mind that you're creating a series circuit. The "+" connection from the driver will go to the "+" on the first LED. The "-" from that LED goes to the "+" of the next LED. The "-" from that LED goes to the "+" of the next LED - repeat until you get to the last LED, then the "-" from that LED goes to the "-" from the driver.
Next, it's off to the drill press. Low speed and a drop of lube on each hole. Back the drill out every few seconds to help clear chips. Getting started:
A little farther along:
Finally, I removed chips and just lightly kissed each hole with a countersink. This helps the screw grab straight, AND prevents a burr on the lip of the hole from causing the LED's star to sit unevenly:
Now it's time to wash the lube and any stubborn chips off the heatsinks:
The heatsink is finally ready to go. Now, we mount the LEDs. You'll need the thermal paste, screws, and nylon washers:
Screwing everything down:
I started moving so fast during the soldering of these fixtures that I didn't really remember to get any photos. So, here's a text explanation:
1) Once the stars are screwed down, prep for soldering. Get the iron hot, cut the hookup wire to length, and tin the ends of each piece. tin the pads on the stars if they're not well-tinned (actually, do this BEFORE screwing them down - it'll be easier). IME the Rebels tend to come with well-tinned pads, while the XR-E come with less solder.
2) Lay the tinned hookup wire on the appropriate pad. Touch the point of the iron to the joint such that as much of the surface of the iron as possible comes into contact with both the wire and the pad. This is hard to describe, but you don't just want to jab it with the very tip of the pointy part of the iron - you want to kind of lay the iron on it's side so that you get more surface area contact. This will speed up the heating process.
3) Wait a second or two, and touch the solder to the joint opposite from/next to the iron. You DON'T want the iron to melt the solder, you want the wire and pad to melt the solder. If you carefully watch the tinned wire and pad while the iron is heating them, you can get a feel for when it's ready, because the tinning will suddenly liquefy. That's when you add more solder.
4) As soon as solder has flowed into the joint, pull the solder off, THEN pull the iron off. If you pull the iron away first, the solder in your hand will remain stuck to the joint!
The one measly photo I took during the soldering process:
It should be noted that I like to use the solid core hookup wire between LEDs, then solder on a short "pigtail" of braided 16 gauge lamp cord to the first/last LED. Then you can put a connector on that pigtail, or solder it to leads from your driver, etc.
Once the solder has cooled, go over the whole project with a multimeter set to the continuity mode. You want to check that pads are connected ONLY to the pads they should be connected to. So, touch one probe to a pad, and touch the other to the pad at the other end of the wire. You should get continuity (my multimeter buzzes which makes this easy). Then, keeping the first probe on the first pad you touched, touch the other probe to the heatsink, and make sure the pad isn't shorted out to the heatsink. It can be easy to have a blob of wayward solder touching the substrate on the star, or the heatsink itself, and cause things to short out. I even had an XR-E that was defective (one of the pads was shorted to ground) so make sure you test!
Once things are tested OK, use a little bit of rubbing alcohol on a paper towel to clean the solder joints. You don't want resin left behind.
At this point, you have a bunch of LEDs screwed to a heatsink and soldered together. Next, I ziptied the fans to the backs of the heatsinks:
Note that I pulled the pigtail of wire from the LEDs through the zipties to act as strain relief. You DON'T want any strain on those solder joints!
When we continue, some info/photos on putting the fixtures together, and using them on a tank!
Since my DIY LED driver thread went over so well, I thought I'd post some photos I took while building one of the nano fixtures I've done recently. Since other threads have covered the theory of these builds well, and given recipes for how to size them, etc. in this thread, I will try to concentrate on the practical steps you need to actually put one together. This will be aimed at people who are beginners (though sadly I missed the photo op for some of the crucial steps). As always, if any of the more experienced people see problems in what I'm doing, please correct me.
When I started getting excited about LEDs over the summer, I wanted to build some experimental rigs to play with a few different variables:
1) Color. I wanted to see what different combinations of LEDs looked like.
2) Control. I wanted to play with controlling LEDs with an Arduino.
3) Positioning. I wanted to experiment with different heights, angles, and positions for LED lighting, to see how easy it was to create dramatic effects.
4) LED choice in general. I wanted to get hands-on experience with all of the common LED choices: XR-E cool white, blue, and royal blue; Rebel cool white and blue, etc. Though the specs are similar, there are some subtle differences (viewing angle, plus the Rebels are available 3-up) so I wanted firsthand experience.
The fixtures in this thread were the result. I built several of these over the summer - a few of them have been running on tanks for a few months; the rest are either on my workbench or have been cannibalized for parts.
These fixtures are built with the following components each. I've done some different combinations of LEDs but this is what ultimately went into use above the tanks:
1) A DIY driver as detailed in my thread above. I built these at 350mA and 500mA. I wouldn't use this density of LEDs on such a small heatsink any higher than that. Cost: $6 in parts.
2) A big beefy CPU heatsink I got from mpja.com for like $4.
3) A mix of three-up Rebels and XR-E, such that each fixture had two of the three-up Rebels and two of the XR-E, for a total of 8 LEDs per fixture. Cost: ~6/ea for the XR-E and ~$16/ea for the three-up Rebels.
4) A stainless steel clip-lamp I got at a big discount retailer. It's sleek, and the bendy neck allows for repositioning to test different angles and heights above the water column. Cost: $9.
5) Several feet of 16 gauge lamp cord. Used for wiring from the fixture to the drivers, and drivers to power supply. Cost: $1 or $2.
6) Some 20 gauge solid core hookup wire. Cost: Practically free if you buy a big spool.
7) A 24v DC power supply. I like the ~6 or ~8A supplies from mpja.com. Cost: $15 or so.
8) A project box to hold the drivers. Cost: $5
9) Some form of dimming or control, if desired. I'll go into it in another thread. Cost will vary significantly, so I'll leave that out for now.
10) Mounting hardware. I used stainless self-threading screws and nylon washers. The washers are to keep the screws from shorting on the soldering pads on the stars. You DON'T want the heatsink live!
11) Misc. consumables - solder, heatshrink, tape, zipties, thermal paste.
12) Cooling fans - the CPU heatsinks I got came with little cooling fans that I used for this project. Any 12v fan of the correct size will work fine. It's tight quarters in these fixtures so I had to remove the stock mounting screws, cut the corners off the heatsinks, and ziptie the fans back on.
Tools I used included:
1) Assorted hand tools. A centerpunch, screwdriver, wire cutters and strippers, etc.
2) A drill. I have a drill press. A hand drill will work in a pinch, but accuracy will be hard to achieve, and you'll get fatigued doing this many holes by hand.
3) A soldering iron. It's HARD to solder the LEDs since the heatsink sucks the heat away. A nice powerful temperature-controlled soldering station will definitely help.
A small nano tank (say, under 10 gallons) would be fine with one of these fixtures. A midsize nano would probably want two (10 - 20 gallons) and a larger nano (20 - 30 gallons) would probably need three. Again though, I built these to play with LEDs, not to light tanks, so study up in the other threads before putting LEDs on a tank. I'm driving these a lot lower than most people, which changes the density (i.e. how many LEDs you might want on a tank). And, since I'm packing a bunch of LEDs into a small area, these fixtures create more of a spotlight effect than other LED builds - this can create some really cool effects but you'll be disappointed if you want a homogeneous distribution of light.
Ok, let's get started.
First, I laid out the stars on the heatsinks and marked the mounting holes. I used a centerpunch because it makes a convenient divot to drill in. Don't try drilling on a pencil mark, the bit will wander and the hole will not be correctly located. Get a centerpunch if you don't have one.
When laying out, keep in mind that you're creating a series circuit. The "+" connection from the driver will go to the "+" on the first LED. The "-" from that LED goes to the "+" of the next LED. The "-" from that LED goes to the "+" of the next LED - repeat until you get to the last LED, then the "-" from that LED goes to the "-" from the driver.
Next, it's off to the drill press. Low speed and a drop of lube on each hole. Back the drill out every few seconds to help clear chips. Getting started:
A little farther along:
Finally, I removed chips and just lightly kissed each hole with a countersink. This helps the screw grab straight, AND prevents a burr on the lip of the hole from causing the LED's star to sit unevenly:
Now it's time to wash the lube and any stubborn chips off the heatsinks:
The heatsink is finally ready to go. Now, we mount the LEDs. You'll need the thermal paste, screws, and nylon washers:
Screwing everything down:
I started moving so fast during the soldering of these fixtures that I didn't really remember to get any photos. So, here's a text explanation:
1) Once the stars are screwed down, prep for soldering. Get the iron hot, cut the hookup wire to length, and tin the ends of each piece. tin the pads on the stars if they're not well-tinned (actually, do this BEFORE screwing them down - it'll be easier). IME the Rebels tend to come with well-tinned pads, while the XR-E come with less solder.
2) Lay the tinned hookup wire on the appropriate pad. Touch the point of the iron to the joint such that as much of the surface of the iron as possible comes into contact with both the wire and the pad. This is hard to describe, but you don't just want to jab it with the very tip of the pointy part of the iron - you want to kind of lay the iron on it's side so that you get more surface area contact. This will speed up the heating process.
3) Wait a second or two, and touch the solder to the joint opposite from/next to the iron. You DON'T want the iron to melt the solder, you want the wire and pad to melt the solder. If you carefully watch the tinned wire and pad while the iron is heating them, you can get a feel for when it's ready, because the tinning will suddenly liquefy. That's when you add more solder.
4) As soon as solder has flowed into the joint, pull the solder off, THEN pull the iron off. If you pull the iron away first, the solder in your hand will remain stuck to the joint!
The one measly photo I took during the soldering process:
It should be noted that I like to use the solid core hookup wire between LEDs, then solder on a short "pigtail" of braided 16 gauge lamp cord to the first/last LED. Then you can put a connector on that pigtail, or solder it to leads from your driver, etc.
Once the solder has cooled, go over the whole project with a multimeter set to the continuity mode. You want to check that pads are connected ONLY to the pads they should be connected to. So, touch one probe to a pad, and touch the other to the pad at the other end of the wire. You should get continuity (my multimeter buzzes which makes this easy). Then, keeping the first probe on the first pad you touched, touch the other probe to the heatsink, and make sure the pad isn't shorted out to the heatsink. It can be easy to have a blob of wayward solder touching the substrate on the star, or the heatsink itself, and cause things to short out. I even had an XR-E that was defective (one of the pads was shorted to ground) so make sure you test!
Once things are tested OK, use a little bit of rubbing alcohol on a paper towel to clean the solder joints. You don't want resin left behind.
At this point, you have a bunch of LEDs screwed to a heatsink and soldered together. Next, I ziptied the fans to the backs of the heatsinks:
Note that I pulled the pigtail of wire from the LEDs through the zipties to act as strain relief. You DON'T want any strain on those solder joints!
When we continue, some info/photos on putting the fixtures together, and using them on a tank!
And, there's no splash shield of any kind, since the fixtures build in these photos were going on a tank with a lid - for tanks with no lid, I'd cut a circle of acrylic and hold it into the fixture below the LEDs to keep them safe. Maybe with some vent holes drilled around the perimeter to keep airflow up.
