My front fresnel is bowed, making the edges of the image out of focus. I have searched the forums, and nobody seems to have a proven solution to straightening out the fresnel.

Has anyone actually tried anything that worked?

I have read somewhere in the forums that someone sandwiched the lens between two pieces of glass.

I have the same problem My wooden frame actually bent due to the heat and caused the fresnel to bow along with it! Now my corners are out of focus and its giving me a slight star burst pattern on the corners. I might try to fix it eventually, but it doesn't really affect anything I do on the PJ.. WS movies where you don't see the corners, and FS video games were I can't even tell the corners are out of focus.

Anywho, you need to sandwich the fressy somehow.. glass/lexan works ok. How do you have it mounted?

I tried boiling mine once in a cake pan with a bakers wire rack underneath it in the pan. I believe I read about a 150 degree F tolarance (double check in the forums) for the acyrlic so I kept about that hot. Then I grabbed the hot fresnel out with tongs and held the edges while quickly applying directional pressure to straighten the curve. It seems to help, but it wasn't a perfect fix. I didn't spend too much time experimenting with it. Maybe better results are possible. I eventually replaced my fresnels with my newer panel. Good luck

Maybe it would be possible to sandwitch the fresnel between a couple pieces of glass, heat up the whole thing for a while, then let it cool... Take out the fresnel and put it back in the PJ (with better cooling hopefully) if it's flat.

My rear fresnel did this when I killed my old pj. My rebuild, I did the sandwich and it works.

a glass sandwich sounds like it would cause a brightness loss...

I also have bowed my fresnel after it got too hot. It's a shame because I thought my cooling system would have been good.

You make the glass sandwich, heat it up in the oven, wait 'til everything cools down flat, then take the fresnel out and put it back in the PJ by itself.

anyone know what kind of temperatures their lcd's are exposed to? i stuck a themometer in mine and over about an hour gradualy crept up to 60 degrees. i thought that this was hot enough. seems like my fans aint as effective as i first anticipated. what do you guys think? cheers

cool, I tried it for about 10 minutes on 170 degrees or so and it came out about 95% flat. I added 2 more 80 mm fans at the top of my PJ and now it seems to be running cooler! my ambient room temperature is about 82 degrees F so I need all the fans I can get.

60º C (140º F) is a little hot... We try to keep the LCDs under 115º F (46.1º C) IIRC...

It would probably be a good idea to change your air paths...


Here's my projector before I changed my fans from intake to exhaust (I didn't change anything else)...
The reading is in celcius by the way...

Note, the temperature probe is above the bulb (heat rises and all that) and it's also closer than the LCD would be to the bulb normally, but still pretty amazing...

Hi Hirudin, ive changed my projector, i have added 2 12v fans into the roof of the pj blowing air down the lcd channel and is expelled out through the front of the enclosure below the triplet. Now my pj stays at about, 22º-24º. Woot
thanks

I put two pieces of wax paper on both sides of the fresnel with pices of glass to sandwich it. then I baked in oven for 10 minutes in a pan with a brick on top. oven was at 125 F

Then remove from oven, allow to cool, and add frosting!
Yum!