LCD Based 3D Printer - Introduction

[AmazingJas]

[quote="oliveenchine"
My actual problem is the resin, I got only sone transparent UV adhesive , normally designed to work with UV ( 365-385nm). I could get some positive results but with a really long exposure (about 3-4 minutes) , I waiting to receive some SubG+ to conduct more tests .
[/quote]

Might sound stupid, and I havent tried it myself, but could you use UV Curable nail polish as resin? Seems to be readily available and has similar setting times and requirements to resin. Easier to get red as well which sets a bit easier too afaik..

[AndersonTa]

Those of you that have pcb designs for an LED array, would it be possible to make that available for others?

Or to help subsidize your R&D so far, would you be willing to sell some?

It'd also help with getting more parties involved on the current development.

We know at the very least an array of UV LEDs is needed...and if not, anyone want to take a stab at designing a PCB for everyone?

[oliveenchine]

If I can get good results with led array and sub G resin I will probably make a batch of aluminium pcbs ( and design it ) , but for now if doing the old way , "star" pcbs arranged on a 200x180mm Aluminium radiator.
I will give also a try to UV nail polish or even UV inks to see what we can get out of it

[Phife]

Ive got around 100 MCPCB's for the LED arrays sitting in my shop.. I also have the ability to reflow solder all the LED's to the PCB. The PCB is designed to allow the 3w LED's and their 20mm lenses to sit as close as possible to each other.

I could place a bulk order of LED's and Lenses and solder them on the MCPCB's and then sell them to you guys. But I would need some good interest as it wouldn't really be worth my time to do one or two.

The specs of my arrays are:
80- 405nm 3w LED's and runs at 36v and between 2-6amps (adjustable) (1 to 3w to each LED in an Parallel/Series Configuration.)
Collimating lenses for each LED
Each array is 9"x6.25" and is able to be tiled to make larger arrays, Tiled arrays have no gaps for uniform lighting.
Each array needs to have its own Voltage/Current Regulation, and a relay to switch it on and off VIA RAMPS or some other board.

I would supply the PCB with the LED's soldered on and the Lenses. I could also supply the LED Driver. You would need to supply the 36v Powersupply.

How about this, If anyone is interested in purchasing an assembled MCPCB LED Array from me please post here with the quantity you would like. If I can get together a some people and say make at least 10 or more panels then I would do it. Cost per single LED Array would be around $200 (includes LED's, Lenses, MCPCB, LED Driver)

Let me know what you guys think.

[hp_]

phife,

I'm up for 2 pieces

hp

[AndersonTa]

Put me down for 2 as well.

So to just clarify, with what you are offering, we just need to bring our own power supply?

[Phife]

Yes you will need a 36v DC Power supply, Either a benchtop one for testing or get a cheap one from Ebay. You wont need the LED kind, a regular switching power supply will work fine. The LED Driver will control the voltage and current to the LED array. The 200w supplies are a good price and will power a single 80 led array to near max levels. You will need larger supplies or multiples if you intended to use more than 1 array. 1 array will cover the 9.6" - 10.2" LCD panels, 4 will cover a 21" panel like the grayscale/monochrome ones im using.

Also, Keep in mind that these arrays are still in "Beta". I will be refining them in the future, but it will get you guys started on making your own LCD Printers! I did a ton of research and spent months designing the array to get it to this point so I hope they will be of good use to you guys! I think they are a good value. I am not making much money at this price, but I would like to see more people working in this type of printer!

The PCB fits many types of lenses. Its hard to take a picture of the evenness of the various lenses but you get an idea.

[AndersonTa]

Which lenses will you be providing out of the 3 shown?

[Phife]

[oliveenchine]

I have some good news !
I measured this morning the light output with the help of the same LED used as source ( 405-407nm) a multimeter keeping my probe alway in the same position(lens in contact with the LCD) :

- Light switched off , no lcd in a semi dark room = 10mV
- Light switched on , no lcd in a semi dark room= 2540mV
- Light switched on , lcd in place, black slide (RGB = 0,0,0)= about 170mV
- Light switched on , lcd in place, White slide (RGB = 255,255,255)= about 1500mV
- Light switched on , lcd in place, Blue (RGB = 0,0,255) slide = about 900-1000mV
values for Red and Green no measured ...

This doesn't give precise value, but looks like the Ipad3 LCD is not so bad for transmitting 405-407nm light, and can cut "efficiently" when turned to black.

Just really need a good reactive resin now !