I want to keep the whole thing straightforward and easy to assemble and adjust. I do not care about looks and size, but image quality.
The only thing I'll use it for is my Xbox 360, so the LCD's only VGA port is alright.

Partlist:

LCD - Samsung 740n - Great LCD. Extremely easy to strip. -- 300 BG leva with VAT, which amounts to about $250
LL Pro Lens Kit + Pro Reflector and LL 65K T15 Lamp and eBallast - $450 + $100 shipping to Bulgaria
MDF box and aluminum frames for LCD/fresnels/lexan - not sure yet, about $200, laser cut
Tempered glass OR Lexan - cheap enough not to bother
Some fans, electronics, fuses, switches... I've got everything lying around, but will probably amount to about $50

ALL - a little more than $1000 so far

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Design has changed a lot. Read on to see what's the latest and greatest

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TOOLS I'm using:
Dremel
Jigsaw
Drill
Battery-powered screwdriver (One of the best things I've bought in my life. Saves hours and your hands on big pieces of equipment with more than 50 screws.)
Soldering iron for electronics (It's not a microscope table, but it works for pretty much everything larger than 0.05mm)

If you can, I would say go check out Google Sketchup. It helped me TONS in the planning stage of things. I still use it now to mock up parts to see if an idea will work.

LINK

Good luck on the PJ!

I ordered LL stuff today.
Tomorrow I'm going to buy the wood for the box and start to build it. First thing will be to secure the LCD, as currently it's sitting stripped on my desk covered by a couple of t-shirts. The only problem is that I have to keep the cat out of the room in fear that it doesn't scratch it.

Just put some aluminum foil on the desk. That will keep the cat away from it.

Cool idea. Care to elaborate? Why are cats scared of aluminum foil?

They don't like the feel and sound of it when they step on it. It has worked for all of my cats so far. They might step on it once, but after that, they will avoid it like the plague.

If your LCD panel is the same as the one shown here, I don't think it will be possible to mount the controller at the top of the box without extending the LVDS cable (unless your cable is much longer than that). Check this section of the Wiki for proper LCD orientation of standard LCD panels. Later on, you say that it will be mounted on a wall. Will there be a mirror involved, as in a folded design? If that's the case, then your LCD will be flipped - allowing you to mount it the way you had planned (with consideration for cooling the LCD).


I understand that you'll consider cooling when your parts arrive, but you'll want an air intake slot to bring cool air from outside the projector between your LCD and rear fresnel. You can read more about this in the Keeping it Cool section of the Wiki.

The cable is maybe an inch longer (I can't tell exactly from the photos). But you're right. I double checked with a sketchup and it's an inch or so too short. I will have to mount it in the box.

I am still trying different cooling solutions (I have this kickass proprietary airflow engineering app) and will post more about it later.

Thank you for the advice!

After a lot of (bad) ideas I've reached a decision. I will explain the logic behind my choices when I have a box.
I have a big-ass AC in the room, which keeps it rather cool, so outside air is guaranteed to be around 25 degrees celsius all year round.
The projector will be sitting right where the AC airflow hits the wall.

For now:

1) 16cm steel big-ass fan on the back side just above the lamp. Exhaust. It's a beast that runs on 220V and moves A LOT of air, also weights a lot.
2) One 12V small PC fan between the tempered glass and the first fresnel. Exhaust. On the side, near the top.
3) One 12V small PC fan between the first fresnel and the LCD. Inlet. On the side, near the bottom.

I tried to do an all-exhaust scenario (so little dust will get in), but this configuration is MUCH better. I will put up an air filter on the inlet.
This is highly theoretical as of now, mainly because I'm rather lazy to try more configurations. Will see tomorrow.

First pictures.

The stripped (and working!) LCD



and the back fan

Forgive my terrible mspaint skills, but it's the easiest program to explain ideas fast.

I've put some thinking into the rails and figured out that the only way to use 'em properly would be to leave some space between the fresnels/lcd and the sides of the case. Second benefit is that it will help cooling.

Could that be a problem? Any loss of light?
My theory is that it doesn't matter, because the light hitting the sides of the box is already lost, so it doesn't matter if the sides are further appart.

See what I'm talking about on the image.

Click to view attachment

Please note that fresnel size is the same on both pictures (it doesn't look like that, I know, terrible drawing skills) only the box width has changed.

I thought my PS drawings were bad .
We both got the same idea with the railing system, that pretty handy.

About your question with the light, it does not mather (much) for the end result because all the light from the bulb - first fresnel is collected in both ways. Light does not reflect (or should not) from the side of your box . But keep in mind that you will have light going between the frames and box side that will interfere with the end result. You have to figure out something for that.

And something about the cooling. I don’t really see how it’s good to blow hot air (from the bulb) to the other side (the TFT) and suck it out there. And if you want it the other way around the air flow will probably not be strong enough.
What I am going to do is put a heating glass (UV/IR filter) and make it air sealed. 2 vents in the back near the bulb. One blowing and one sucking out the air. That way the TFT should not get much hot air from the bulb. And then think of a way to simply cool the screen/lenses.

Ps. I think I know why you want some space between your frame's and TFT. Is it because otherwise it will be to tight to slide? If that's the case you could try something like me. Use foam on the sides that gently close the gap
Check out my BLOG in a hour to see what I mean .

//edit. Ofcourse you need a small distance (5mm or smaller even) between the case and frame/tft for it to slide easy. So in both our cases I would suggest the foam sollution. I'll see into it.

Blocking off the light engine won't be enough.


http://www.lumenlab.com/forums/index.php?s...st&p=238179

This is why it's best to have cool air entering the projector between the LCD and rear fresnel - to get rid of that built-up heat.

alucardu is correct in saying that light that enters the front of the projector will wash out the image prior to it entering the triplet. Ideally, you'll want to have the front of the projector sealed off from the LCD forward.

Okay so it's better to have a little bit of room between the UV/IR Glass and bottem, 2 fans on the side of the case blowing cold air between TFT and fresnell's and that air being sucked out at the back of the projecter by 2 fans near the bulb. Yea I saw some picture's of that.

You really shouldn't need any more than two fans in your enclosure. Depending on the heat generated from your lamp, one might be sufficient.

As you can see from the Keeping it Cool section of the DIY Projector Guide, this is the tried and true method of cooling your projector:

Hey Quasi_Mojo thanks for are you're fast and good replies. Now I dont want to be a smart ass but doesn't hot air go up? So on that pic all the hot air is in the top of the projector with no good way of leaving. Wouldn't it be better if you put the exhaust fan on top or behind the bulb? Or am I overcomplicating things .

You're correct. But cooling the lamp chamber is secondary to keeping the LCD cool.

In my projector, I have the cooling slot on the bottom and the fan on the top rear.

thats how I did mine: 9/16" wide, and 13" long cooling slot under and between the lcd and rear fresnel with the air being pull up and over the rear fresnel/lexan && six 9/16 holes spaced under the lamp, and forward of its physical location- to draw air over the bulb. Pulled by dual 120mm fans ( in the top rear )funning full blast at all times. I still need some flash extended a few inches more forward top and bottom. I have some for the lamp but the ply is getting a bit warm.

After some thought I gave up the rails and decided to KISS.
So it's four rods for me now (;

Of course, it was back to the drawing board and..

(btw is 850x500x450 (all in millimeters)) too big of a box?)

Click to view attachment

Not sure about the size, no experience with 17". I'm going through with the rails . At least for now haha. Good luck.

I decided to cut the fresnels to a smaller size. Is 1/4'' bigger than the LCD enough?

It should be. I think most people like to keep it to about 1/2".
My fresnels were pre-cut and are almost the same size as the LCD. Keep in mind that the active part of the LCD is smaller than the outside dimensions.

Thanks!

*DELETED*
See next post.

No photos today. I still have to go buy the MDF.
Reached following decisions:

* Box size - 850x420x450 (mm)
* LCD and fresnels will be mounted in solid frames which will be a snug fit for the box. I will glue the frames to the box after I get satisfying test results. I am an adjustment junkie, so I will probably start building a second "more advanced" box as soon as this one is complete.
* The frames will be made from one piece MDF by cutting out the center with a jigsaw and a dremel and leaving 5mm space for the fresnel to fit in. It will be secured by two aluminum braces on the back.
* Lamp & reflector will be mounted on a fully adjustable aluminum stand, which I plan to make from an old PC case.
* Ballast will be mounted outside on the top of the box.
* Thanks to Quasi_Mojo I've decided to use only two fans. The 16cm 220V one in the back (exhaust) and a 12cm PC case fan on the bottom of the box between the LCD and first fresnel (inlet).
* I will do a temperature test when everything is complete without the LCD to see if the airflow is indeed working fine. It will be at least a week (maybe 3) before LL stuff arrives, so I have a lot of time to perfect the box.

Here is 740n's LVDS cable. It's just over 15cm (6'') long and I think that it is possible for the electronics to be mounted outside the box. Comments appreciated.

Click to view attachment

Hey bro, dont you need to blow cool air down (put the fan in the top).

SIDE VIEW
Click to view attachment

That's the only way to achieve flow. Otherwise you're just mixing air and there could be really hot airbubbles left, which could damage the LCD. The only way to ensure there are no bubbles is to have a good flow.

*EDIT* I've messed up the drawing. The fan has to be between the FIRST fresnel and the LCD.

*EDIT (2)*
It's important to know that this design is negative pressure (more air going out than coming in). You can probably get away with just the fan in the back.
The best thing will be if you can get a positive pressure flow with an exaust back fan, but I fear that it is highly impractical as you would have to mount a large fan between the LCD and fresnel.

*EDIT (3)*
Never seal your box completely. Both positive and negative pressure benefit from holes in the box.

And as the trend is.. a photo of my assistant..

Click to view attachment

After a lot of thinking on the box I've decided that I could never do a 1mm precision with the tools at hand (jigsaw and dremel), so I've fallen to the dark side and chosen the simple route - laser cutting. I am expecting the finished parts in the next 3-4 days. Damn you, CNC and modern technology!

Here are the drawings of the frames for the LCD/fresnels/tempered glass, manufactured from 1.5mm aluminum.

Click to view attachment

Design changed a lot since the first post. Here are some current details:

* Box made from 20mm MDF with dimensions of 850x491x436 (mm)
* LCD/fresnels/lexan mounted in laser-cut aluminum frames (see previous post).
* Frames mounted on four threaded rods (8mm)
* Two fans cooling the box. One in the back, one on the side between the first fresnel and LCD.

I'm waiting on both LL parts and MDF/frames, so work is stalled at the moment.
I am planning to do AG removal today and will post photos.

One side AG is off. Doing the other side now.
It was really easy, I used an old t-shirt, which I cut down to the size of the LCD. It soaked for 2 hours. I sprinkled more warm water on top every twenty minutes.
Some photos follow:







Really blurry, I moved the camera away too soon.


Here you can see the obvious impairment of the antiglare

Good job, I'm going to fix my beamer and maybe afterwards strip the AG .

The AG on the other side was maybe 2-3 times thicker, funny stuff (no, it's not the polarizer). It broke off into about 90 small pieces and was a VERY tedious task. Maybe I didn't let it soak long enough. I managed to break a fairly large piece of the polarizer beneath it, but, thank God, it's outside the viewing area. Still have to remove a fairly large piece, but I will let it soak for about 15 minutes more before trying. It's really hard to pick off edges of the AG in the viewing area, because it's extremely easy to scratch the polarizer, but I managed to do it with a steady hand and a stanley knife (I know I'm crazy). I am going to inspect the LCD closely when I finish removing the AG, but I don't think I've done any damage (so far).

To be continued..

EDIT:
I'm thinking of ordering some new polarizer just so I can remove the f***er.

Got frustrated, removed the whole polarizer. I'm ordering a new one from polarization.com
I only need one piece, right? Because the other side is intact.

Shit. Broke an FFC while cleaning the glue from the polar. Maybe it's for the best, now I can test my construction without worrying about the LCD.
I'm gonna buy a new one (the same, it's a really really great LCD and it costs $250) and put it in when everything else is finished.
This is my last post until everything arrives (~3 days) and I start to assemble it.

I know what it's like to kill an LCD and have to shell out that much for a replacement. You seem to be taking it in stride, which is great. Killing my LCD just about made me quit.

Best of luck to you on your second strip!

I've already shelled out about $550 on LL stuff and about $200 on parts for the box. I can't quit

MDF arrived today. It's.. a lot. It's also laser-cut, polished and perfect down to the tenths of the millimeter.

Click to view attachment

Cost: 116 BG leva, which is about $95

For anyone that's interested.. Here are all the dimensions for the box and frames.
I do not have the CAD files, sorry.

Enclosure. Made from 18mm MDF.
All dimensions in millimeters.
Two of each.

886 x 491
886 x 436
461 x 436
Cost: $95

Frames:
Made from 1mm aircraft grade aluminum.


Fresnel frame will be uploaded soon.

Cost: $120 (2 for fresnels and 1 for LCD)

All laser-cut.

Painted the MDF. LL stuff coming in tomorrow.

Nice bro .

Frames arrived today. Still waiting on LL stuff.

Click to view attachment