I recently melted the old OHP I was using to project movies, so I now get to start building my own case and everything way before I had planned! This is pretty exciting, especially considering that I am up at college and have very limited access to supplies and tools. I have manage so far to buy the wood, I got 1/2 inch thick MDF, and the gave me some rudimentary cuts to the specifications I wanted. Attached is my design, a box I modified to be a bit more angled like the Haas design. Even though this is my first project I am not interested in making something that is going to look terrible sitting in my living room.


So far I have pieces cut for all the sections in the schematic. I still need to angle the cuts on the wood so the fit well together. The side pieces still need to have the angled cuts taken off as well. I have everything except the new lenses, though I need to clean the old molten pieces of the OHP lens that dripped onto my bulb off.


Supplies I have as of now:
LCD (stripped and everything)
Light and associated electronics
1/2 in thick MDF (4x8 sheet, mostly cut)
Wood Glue
Screws
Flat black spray paint

I will update when I get further with the construction of the box. Please post if I forgot anything obvious from the schematic. Just to clarify though, the wood in the center I might just replace with flashing to keep light from hitting the ballast, the bottom part of that L I will only put in if I have to put the LCD electronics there (which I wont if my measurements are right), and the light path has been measured out properly (though I didnt include those measurements on that schematic).

-ZJ

I think I will have problems with the focusing mechanism. I think I am going to try a sort of box within a box, but since my box is so narrow at the end I can't have anything extending back into it. At least, not a box as small as the front panel. I think I will have to build a box extending forward, then build a box to go in there holding the lens, with the lense at the back and the side of the box extending forward. Hopefully I can make the inside box holding the lens as small as possible, and then cut a channel in the outside box for a screw attached to the inside box, which I will use to change the focus.


Can anyone describe how the light is going to travel when it hits the focusing mechanism? I know it is supposed to focus right before the triplet, does moving the triplet forward to focus it mean the whole light path gets wider? Or does the light cross at the focal point before going to the triplet, so moving the triplet forward is only a matter of having the room to capture the light. I remember reading something on this, but can't remember at this moment what it was. FOV?

-ZJ

I cut almost all the pieces to size today. Cut angles into the wood to, so it all assembles well. I wont be able to do more woodwork for a few days, but I will make a few measurements for things such as fan placement, ballast, and the few pieces I have left to cut. I will also probably start painting the interior black as well.

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Here is the mock up of the box for the focusing mechanism. I was freaking out last night (probably due to sleep deprivation), but I am not sure I am going to have such a big problem anymore. I will see once the lenses come in.

-ZJ

P.S.- Go ahead and reply. It is getting lonely in this thread all by myself.

I put the box together today. I am going to give it until tomorrow to let the glue sit, then I will spray paint the inside black. Is primer going to be necessary? This is just to keep reflection in the interior down, so I am not too worried about an even coat. Lenses come in Tuesday, and I will see about building a lens sled before then. I realized today that I have an extra inch width wise to work with. I'm not sure if I need it, but I guess its there anyway. It might actually make building the sled more difficult.

For a focusing mechanism I have a pipe that has about a 4 inch diameter. Anyone have any suggestions as to how to convert this into something I can use? Perhaps find a smaller pipe, or cut a piece of wood to its diameter and then fit the lens into that. Maybe cut a slit into the pipe and run a screw into the wood, with which I can change its position.

I forgot to mention that I managed to cut myself on the wood the other day when I was sanding a rough corner, so the blood for this project has already been paid. Since this has been gotten out of the way, I expect no more complications.

-ZJ

After reading through some more plogs, I decided that I probably really can't get this thing running without a heat shield in front of the collimator fresnel. I had this naive dream I could do without it, stemming mainly from my complete lack of any idea of where to get one, but my box is tight enough that I fear heat could be an issue. I have built in two exhausts now for some 80mm fans, and I have plans for a long intake right between the collimator and lcd. I am still debating on whether I will put the intake on top or bottom, though considering that it will be lying flat on a table it would be easiest to just put it on top and not worry about raising it up at all. Out of curiosity, what do I always see people using to block light from exiting out of the projector at the intakes and exhausts? Air filters?

I will take pics soon hopefully, but I think I have to stress again how I am up at college in the middle of nowhere with no access to, well, basically type of regular tool or material. I had trouble just buying wood, now I have to find out where I can get tempered lexan.

-ZJ

Air conditioner filter cloth. Good luck finding it "in the middle of nowhere".
Lexan can usually be found at Home Depot-like stores. If you have any around, which you probably don't. Perhaps you can order online from a California supplier.

Google: California lexan

I found a hardware store nearby today. I haven't been inside but it can't be too big, seeing as its in this tiny college town I am in. I will look for filter cloth, I will hopefully be able to find something. I will try ordering the lexan online if I can't get it here, but I think I will wait on the filter cloth. Thanks for the reply.

Finally found someone who would let me borrow a camera, so here are three pictures of the case as it stands today. I plan to get some wood putty to fill in some of the whole and to sand down some of the protruding edges. Anyone have a particular brand of wood putty they would suggest?

Anyway, here are the pictures:

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I cracked my bulb trying to clean it. If anyone read my post in the beginners forum it describes how my last projectors lenses melted onto the bulb. Well... cleaning it didn't work so well. Lumenlab is out of 400 watt bulbs too, so I am now looking for another replacement. Anyone know any other good 400w bulbs?

Edit: I also have a piece of glass I need to cut from my overhead projector, can anyone tell me how to do it safely?

Edit 2: One quick google search later, BAM! There seem to be many ways to cut glass without any special tools at all! Anyone try any of these methods (cutting glass under water, heating it on a line and then quickly submersing it in water, etc)?

So I now have a really interesting question. Stuff exploded today with my lcd monitor. Huge sparks. I am pretty sure I shorted out the power board for my LCD monitor. I have a NEC multisync lcd 1550V. So does anyone know where I can get new controller boards or where I can get a pinout to get power straight into the lcd controller board? I may have only destroyed the power board...

I know there are controller boards for laptop screens but are there any basic ones for monitors?

-ZJ