Build Your Own SLA/SLS

hi, I'm looking for a type of led to illuminate a vat

specifically in regard vith this mod

It would help so much to see if a print is starting correctly instead of waiting a hours to see ...

So what type of led would not cure the resin or/and interfér with the projector... (red led, blue?)

from what have gather normal colored led as completly usless for curring typical makerjuice resine.

thanks

I think that almost any 2700K LED will serve your purpose.

I have my printer room lit up with 5 of these:

http://www.homedepot.com/p/Cree-100W-Eq ... /205054835

and have no problems with unwanted curing, even for insanely fast resins like the Venus Creator clear, and can provide good lighting for photos and videos.

In contrast, my sink area is lit with fluorescent lighting, and droplets of Venus Creator left in the vat will cure solid in a few minutes. But in my print area lit with the 2700K LED bulbs, I've had no premature curing even after hours and hours of exposure.

What you'll see if you take a look at the Cree datasheets for the individual LED modules (hard to say which one is in the bulb, but nearly all of the high powered whites across product lines have the same spectrum):

http://www.cree.com/~/media/Files/Cree/ ... XA2011.pdf

Is that the LEDs put out pretty much nothing below 405nm and almost nothing below 420nm. 420nm is the top end of what will cure BAPO, which is one of the most common photoinitiators used in resin.

If you're buying LEDs by the reel to do some kind of custom lighting job, from what I've seen, most vendors' 2700K white LEDs have a similar curve on the blue/violet end, and just about any brand will do fine.

Full visible curing resins like the new Photocentric daylight resins are probably a different story. I'd be willing to bet that those probably use a "784" type photoiniator (Bis(.eta.5-2,4-cylcopentadien-1-yl)-bis(2,6-difluoro-3-(1H-pyrrol-1-yl)-phenyl) titanium ) which has a big area of strong reactivity from 380 to 500nm, and will probably cure with light as high as 530nm, which takes us into green territory. If you're using that, you probably need something a bit more yellow.

With those resins, you might need something like:

https://www.superbrightleds.com/moreinf ... ight/3078/

I have one and plugged the supply into one of the 12V outputs on my printer's RAMPS board, allowing me to control the light with G-code. I shined it directly at my vat (not daylight resin, I don't have any of that) at close range for hours with no curing effect. The color made for pretty terrible pictures and offended my senses, so after I figured that the 2700K LED bulbs were fine, I retired the amber light.