It's Time To Build A Grow Light

[Old Salt]

Check out Rapid LED, they have some content that may help. They sell a lot of GrowMau5 gear like his pucks which are essentially the exact same thing as a QB but in a different form factor. Likewise, a search of quantum board will turn up a lot of content too.

I've bought far red diodes and some other parts from them for DIY initiator pucks. I've just got too much on the go right now to put them together. It's coming, just not soon.

 

[VetSmoke85]

I ended up buying a HLG Quantum board which is doing the job nicely for now. Thanks for the info though. I'm hoping to buy a house towards the end of this year that should give me the space for a bigger grow area and then I'll be building something. All going well.

 

[BobbyZ]

You should find a cheap wench and wire it up. Then you’ll have push button adjustment.

 

[odam2k]

You should find a cheap wench and wire it up. Then you’ll have push button adjustment.

Heck, you'd have voice control....

 

[Old Salt]

Heck, you'd have voice control....

No, the cheap wench would have voice control.

 

[Aroxol]

No, the cheap wench would have voice control.

When you get to cheap the logic breaks down

 

[HydroponicFireman]

.....so THATS what a turnbuckle is...

 

[Old Salt]

I just came in from putting the last coat of Epoxy paint on the hanger. I just realized I still need to make the connector for the force multiplier pulleys. There's that and I need to buy some cord to finish it off, hopefully tomorrow.

I should come up with a name for the device. Perhaps 'Lite Lift 1.0.' Perhaps not, as it's also a surgical procedure for a face lift. Thinking...

 

[HydroponicFireman]

Old Salts' Trusty Ol' Airborne Slipway 1.0

 

[Aroxol]

You make some good points. Something else to consider is where the light is used. In an open area light is lost all around the grow area. In an enclosed space with highly reflective sides such as a grow tent much of this light is bounced back into the canopy.

It won't hurt to map out the coverage, even though it may prove to be an exercise in futility. In the end. the proof will be in the results. Due to the design of my light, a simultaneous comparison grow is impossible as I can't operate at two different heights. The results of sequential grows, even with the same strains would be questionable, since the environment (temp, humidity) will change. What I can do is test the penetration into the canopy, with and without the reflectors. This will have to be put on hold until my

I have been thinking about adding 2 more blue COBS to my array for veg and have been thinking a lot about not putting reflectors on these so that this light would spread out and mix with the other full spectrum lights while in veg.

I still think the reflectors serve a purpose. There may be bright and dark zones at various places under this array, but I don't think this matters to a plant sitting under it getting brighter light in one spot over another.

Consider too that at 6" you are really going to have some bright light there, but at 12 or 18" you are going to have multiple overlaps of varying distances and angles, all additive.

But again, being able to direct all of that light downward, not just 70% of it, by using a reflector, has got to help with penetration through the canopy. A good reflector is going to give you 98% of that output going downward, right where it needs to be. I am just not sure how much having even coverage is more important than forming these strong beams of canopy penetrating light or whether that even matters with these LEDs.

Depending on your current driver/ layout, these may be worth a look. I run the red spectrum pucks and they just came out with these (kind of a special edition test run to see market demand). Almost bought 2 yesterday but would’ve required a new/ different $170 driver to run 6 pucks so decided against it.

 

[Old Salt]

The rope arrangement I showed in the diagram will not work. The force multiplier does nothing. I'll go to single and double sheaved pulleys to accomplish my goal of reducing the force needed to lift the light. Hopefully I can finish it tomorrow.

 

[Old Salt]

Finalized Concept Drawing

Detail: Top of Hanger
​

The shafts for the sheaves and snap hooks were made from 3/16" steel rod. This was the perfect size for a #10-32 die. The rod was clamped in a vise between two blocks of wood. Eight threads were cut on the end which was 1/4" of thread. The shaft was cut to length off of the rod. Two nuts were locked together on the threads, and clamped in a vice. 3-1/2 or eight threads were cut on the opposite side of the shaft. The shafts at the side of the tent were cut shorter, and threaded into the aluminum u-channel to prevent wear on the tent wall.

The sheaves mounted in the hanger were removed from 3/4" (20mm) pulleys. The shafts were ground down to the block, and punched out. The holes were too small for the 3/16 shafts I used, and needed to be drilled out. I did one with a hand drill to determine how to do it. The easiest way was to wrap the sheave with a piece of rope, and clamp it in a vice. Care must be taken to keep the hole square with the face of the sheave. For the remaining five, I cheated. I chucked them up in my lathe, and drilled them out there. The sheaves were drilled 1/64" oversize so they would turn freely on the shaft.

The sheaves were mounted on the shafts, with washers filling the remaining space. Note the fender washer between sheaves two and three. There is a standard washer, the fender washer, and another standard washer between the sheaves. The standard washers do not extend to the rim of the sheaves, so this arrangement reduces friction. The fender washer prevents the cord from jumping sheaves. I highly recommend using this arrangement where ever the sheaves are spaced away from the u-channel walls as well, for the same reason. I'll upgrade this later.

The turnbuckle / snap hook arrangement connects the two sides of the light fixture to the main pull rope. The core is a scrap piece of the aluminum u-channel. The threaded eye has a washer followed by two nuts locked together. For extra security, I used a center punch to peen over the threads so there's not a chance of this coming apart.

The ratchet hanger was a disappointment. There is a lot of friction in this device, and the fixture will not lower by its weight alone. I need to find one of better quality.

Detail: Bottom of Hanger

Light Fixture as Low as Possible

Light Fixture as High as Possible
​

The fixture can be lowered to within 6" or 15cm fron the tent floor, and raised to within 10" or 25cm from the top of the tent. The force required to raise the fixture is approximately 1/3 the fixture weight, of 32 lbs, or 14.5 Kg. That fixture is heavy, but well within the capability of the tent frame.

Let There Be Light!​

As you read through this part of the thread, you'll realize that I started with several misconceptions. The major one was the functioning of the pulleys. You can tell that I was not a Boatswain's Mate in the Navy.

Over all, I'm happy with the way this turned out.

Next, ventilation needs to be addressed.

 

[BuzzedOldMan]

That will grow some weeds . . . very nice!

 

[SlyTown420]

Just awesome @Old Salt! It's blinding on the low dim setting.

 

[Old Salt]

Just awesome @Old Salt! It's blinding on the low dim setting.

I can't directly look at the light. At 18" (46cm) it is brighter than the sun at high noon. It's over 120,000 Lux, the maximum my app will measure.

 

[SlyTown420]

The theme from The Empire Strikes Back just played in my head... thought about you lowering that beast on your insanely genius pulley system at 120,000 LUX. Blindingly good for the plants!

 

[Aroxol]

OS, any ideas on a streamlined (non-damaging) way to easily turn off DIY lights that only dim down to 10%? It’s a pet peeve of mine because there’s a lot of random times I shut down lights in my tents to do some work for a few mins and I’d prefer to not unplug/ plug in every time. You have a lot of clever ideas and curious for some thoughts you may have.

 

[Old Salt]

I did a temperature test of the fixture today with the tent open, and no fans on. I used an infared thermometer to check the temperatures.

Room temperature was 21°C / 70°F
@ 100W COBs: 23°C / 73°F; drivers: 25°C / 77°F
@ 200W COBs: 25°C / 77°F; drivers: 29°C / 84°F
@ 300W COBs: 30°C / 86°F; drivers: 33°C / 91°F
@ 400W COBs: 33°C / 91°F; drivers: 36°C / 97°F
@ 530W COBs: 40°C / 104°F; drivers: 42°C / 108°F

 

[SlyTown420]

Those don't run too hot at all @Old Salt. Readings of an SP-250 hit 140°F.

 

[Old Salt]

OS, any ideas on a streamlined (non-damaging) way to easily turn off DIY lights that only dim down to 10%? It’s a pet peeve of mine because there’s a lot of random times I shut down lights in my tents to do some work for a few mins and I’d prefer to not unplug/ plug in every time. You have a lot of clever ideas and curious for some thoughts you may have.

Other than a switch, relay, or pulling the plug, there's nothing you can do. I just checked Rapid LED. They don't have a plug in relay module for the Coralux Storm or Bluefish controllers.