4x2.5 cab outfitted with a diy cxa3070 build
- Thread starter Al Yamoni
- Start date
Al Yamoni
Well-Known Member
It looks like you were onto something and the spec sheet I posted is flat out wrong..
Al Yamoni
Well-Known Member
So now my board is prepped for the new LEDs. The four duds that I removed were all red.
I wonder if there is a connection between the different voltages among the different colored LEDs..
Anyhoo, should I get red ones or can I put other ones on there that can handle closer to 3volts?
I wonder if there is a connection between the different voltages among the different colored LEDs..
Anyhoo, should I get red ones or can I put other ones on there that can handle closer to 3volts?
Al Yamoni
Well-Known Member
I just have to say thank you again Mike. This was super easy and a lot of fun too! I can't wait for the next step. I'm getting so close!
Mechmike
Well-Known Member
Glad to help! Did you get it working? I see a DIY fixture in your future...
Al Yamoni
Well-Known Member
Just need drivers and to solder new LEDs in place of the ones I removed. The only ones that burned out were red.
If the current is too strong for the reds normally, would running the string softer fix this problem?
I just don't know if I should replace them with red or another spectrum.
Mechmike
Well-Known Member
Running softer will definitely be easier on the emitters. Just make sure you get 3 watt replacements. They can handle up to 700ma when cooled well. The "heatsink" used in these lights is really inadequate to run the emitters at full current but they do hold up much better at 350ma. The light I retrofitted with low current drivers has been running for more than a year now without a hiccup. The friend I sold it to is satisfied.
nestor
Well-Known Member
If you have access to either a drill or drill press then drilling and tapping works very well with that chip holder you have.
Pick up something like this:
http://www.mscdirect.com/product/details/77277705?CS_010=77277705&item=77277705&CS_003=7867724&src=pla&cid=PLA-Google-PLA - Test
You can most likely find something cheaper from somewhere else, just the first thing that popped up in a quick search.
First mark the holes on the heatsink, then dip the drill bit in cutting oil (vegetable or olive oil will work) and drill your holes. After the holes are drilled use the tap to thread the holes (requires a tap wrench - for 10-32 it needs to be a small one.) This requires oil too. Then its 2 turns in, 1 turn out. Repeat that until you have it threaded all the way down, then get some small screws with a 32 thread pitch and you're set.
EDIT: Forgot to mention, try to find screws that are NOT pointed. If you screw it in too tight it can anchor itself into the bottom of the hole. Same thing can happen with the tap if you're not careful. Through trial and error I learned its best to drill farther down than the threads need to go so that you don't end up snapping the tap off in the hole trying to get it out.
And of course don't forget the thermal grease on the back of the COB!
Pick up something like this:
http://www.mscdirect.com/product/details/77277705?CS_010=77277705&item=77277705&CS_003=7867724&src=pla&cid=PLA-Google-PLA - Test
You can most likely find something cheaper from somewhere else, just the first thing that popped up in a quick search.
First mark the holes on the heatsink, then dip the drill bit in cutting oil (vegetable or olive oil will work) and drill your holes. After the holes are drilled use the tap to thread the holes (requires a tap wrench - for 10-32 it needs to be a small one.) This requires oil too. Then its 2 turns in, 1 turn out. Repeat that until you have it threaded all the way down, then get some small screws with a 32 thread pitch and you're set.
EDIT: Forgot to mention, try to find screws that are NOT pointed. If you screw it in too tight it can anchor itself into the bottom of the hole. Same thing can happen with the tap if you're not careful. Through trial and error I learned its best to drill farther down than the threads need to go so that you don't end up snapping the tap off in the hole trying to get it out.
And of course don't forget the thermal grease on the back of the COB!
Last edited:
Al Yamoni
Well-Known Member
Thanks for the details nestor! Much appreciated! I guess it's off to the home depot again..
Abiqua
Well-Known Member
I would look for a spiral flute bottom tap or thread form bottom tap. 4/40 and #4 equivalent.
Bottoming taps will cut threads all the way to the bottom of the hole with very little taper and the metal is pushed back and out from the cut. These are the hardest taps to cut with, free hand, but they leave a pristine hole when done right.
Thread forms don't cut but actually shape the metal and are supposedly easier to work with and overall stronger as they are cold formed.
The irwin tap above is a plug tap and not a bottoming tap and really should be used for thru holes and not blind holes. I have a similar Irwin tap set [they are common in the states] and while they work, they are not preferred. They will push metal forward into your hole at times [if you aren't constantly cleaning it out] and this is the #1 way taps, jam and then break.
M3 .4/.5 pitch 6mm machine hardware is a perfect fit for screwing the cob down...
Bottoming taps will cut threads all the way to the bottom of the hole with very little taper and the metal is pushed back and out from the cut. These are the hardest taps to cut with, free hand, but they leave a pristine hole when done right.
Thread forms don't cut but actually shape the metal and are supposedly easier to work with and overall stronger as they are cold formed.
The irwin tap above is a plug tap and not a bottoming tap and really should be used for thru holes and not blind holes. I have a similar Irwin tap set [they are common in the states] and while they work, they are not preferred. They will push metal forward into your hole at times [if you aren't constantly cleaning it out] and this is the #1 way taps, jam and then break.
M3 .4/.5 pitch 6mm machine hardware is a perfect fit for screwing the cob down...
nestor
Well-Known Member
just a heads up, the PVC frame you have is going to block the airflow on your heatsinks almost completely. you may want to cut out some rectangular holes (just a small drill bit all the way through the PVC then move the bit left to right) to open up some air flow making the fans functional. Otherwise you'll have to run the fans harder for less cooling.
Al Yamoni
Well-Known Member
Thanks for the detailed input!I would look for a spiral flute bottom tap or thread form bottom tap. 4/40 and #4 equivalent.
Bottoming taps will cut threads all the way to the bottom of the hole with very little taper and the metal is pushed back and out from the cut. These are the hardest taps to cut with, free hand, but they leave a pristine hole when done right.
Thread forms don't cut but actually shape the metal and are supposedly easier to work with and overall stronger as they are cold formed.
The irwin tap above is a plug tap and not a bottoming tap and really should be used for thru holes and not blind holes. I have a similar Irwin tap set [they are common in the states] and while they work, they are not preferred. They will push metal forward into your hole at times [if you aren't constantly cleaning it out] and this is the #1 way taps, jam and then break.
M3 .4/.5 pitch 6mm machine hardware is a perfect fit for screwing the cob down...
View attachment 3327678
What type is this?
Al Yamoni
Well-Known Member
I can't believe I overlooked that.. Good lookin for me!
Abiqua
Well-Known Member
it is a spiral tip plug tap...see how about 5-6 threads on the bottom have a taper? These can do blind holes, but not ideal and the sizing is off, at least as far as recommend by Cree....let me see if I can find that sheet.....
Here is a better view of what I bought: