Rear surface mirror any good?

[jaycey]

Im putting together a spiro and only have a sheet of acrylic rear surface mirror, the shaft of my motors is only 1mm.

Do you think it will still be ok or will the shaft showing mess my beam/image up?

Jason

 

[Meatball]

I think mainly the fact that your mirror is not front surface, is where your reflection distortion will come from. There are some cheap, suitable mirrors at dark lasers.

Front Surface Mirrors : Dark Lasers, The one-stop shop for all your DIY laser needs!

I'm not too sure about what you mean about your shaft though..

But I hope this helps!

Tyler

 

[jaycey]

OK, I thought my problem would come from the shaft being visible from the front.
Didnt think about the reflections...derr!

Ile give them a try as I have them and get some FS mirrors as well.

Cheers

 

[daguin]

Rear surface mirrors will give you a "shadow" projection. You will get one reflection off of the rear, mirrored surface and one weaker reflection off of the front surface of the glass. As you can imagine, this is NOT a good idea if you want the projection to be "clean."

Peace,
dave

 

[Benm]

Indeed, reflectivity of back silvered mirrors isnt really a big problem for an application like this, but you will get a sort of double-image projection. Same thing that produces 2 dots when you shine a pointer at a (bathroom) mirror. Somtimes the light also bounces a couple of times between the mirror and front surface, producing a row of dots - depends on the angle and thickness of the glass.

 

[bobhaha]

I'm not too sure about what you mean about your shaft though..

But I hope this helps!

LMFAO that what she said!! sorry couldn't resist!

 

[Hemlock_Mike]

As stated, use first surface mirrors. I've heard of some people removing the coating on the rear of a mirror and finding a good FS mirror.
Also --- Keep the mirror as light (massless) as possible. They can move faster and with less overshoot.

Mike

 

[jaycey]

What your saying has jogged my memory Mike, cant remember where it was but I too have read about removing the first coat on the back of a mirror...ile experiment with some 'substances'

I wont have to look at any shafts eh Bobhaha!

 

[bobhaha]

lol hopefully not!