I just picked up an HP XB31 from a sales rep who dropped it.

It fired up but was dim in half the picture and badly out of focus (focus ring was crooked)

I took it apart and repaired the entire lens assembly and improvised with the plastic gromits that move the lens up and down with the twist. The projector is now crystal clear and zoom works as expected.

There is a mirror along the front side of the "light chamber" that broke in two. See attachment for pic...

The mirror that was there was two sided. It was shiny on both sides, a duller brown mirror on the non lighted side, and regular mirror on the inside.

Gluing it was not precise enough to keep the light focused, so I was going to have a glass shop cut a small piece of mirror.

QUESTION IS HERE!
Do you think it matters that it was double sided. Can I just have a regular piece of mirror with black backing cut to fit the area and attach it?

Thanks for any ideas or help!

It's a first surface mirror. I'd get a first surface mirror cut instead of a regular mirror. They reflect more light. They have websites where you can buy them and have them cut to size. Or you can cut it yourslef with a glass cutter.

Thats exactly what I was looking for. I have contacted a company with the measurements, hoping they can cut the shape I need for a reasonable price.

Please respond back to where I can get a name of a respectable glass company to cut the XB31 mirror for my projector. My primary mirror, (on the bend held in place by a metal bracket), shattered and I have no idea what it's original length x width was.
Any help would be greatly appreciated.

BooVuc

It's a first surface mirror. I'd get a first surface mirror cut instead of a regular mirror. They reflect more light.

The main reason for a first surface mirror is that a regular mirror has two reflective surfaces, the regular silver part in the back and the glass in front. Since the two are slightly apart - by the thickness of the glass - the light is reflected from each surface slightly offset. You'll get the primary light from the mirrored surface and a dimmer reflection from the surface. Add them together and you get a ghost or fuzzy looking image.

Another thing to consider here is heat. It may be that the original part is made from a high temperature glass like Pyrex. A standard mirror may break or even explode when exposed to all that heat.

If at all possible I would suggest trying to get an original replacement part.

Thanks for the explanation of the primary mirror's function. I agree that it may well be made of Pyrex or other heat-resistant glass. Trouble is.........HP doesn't support this 2002 model projector anymore. I haven't been able to find a parts schematic or repair manual for it and their tech-support people have no part number or component parts for it with the exception of the 500 dollar replacement bulb. I'm not sure who actually made it for HP. It may be an NEC with an HP branding but who knows for sure.
I'm waiting for Mbaran's email on the original size of the primary mirror and the company he used for his projector. As of now, it's my only prayer to bring this unit back to functional status.
Thanks for the reply!