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Discussion Starter #1
Let's say for a second that you can get mirrors on sheets of paper. No glass on them, mirrors as thick as a sheet of paper. Perfectly reflective mirrors, but next to no rigidity to the material - just like that sheet of paper. Cut-able, moldable, bendable.

You get to mold/cut and glue/whatever this sheet of mirror on to whatever you want, to make a reflector for t-8 or t-12 bulbs.

What would you use for the rigid backing? Grab some rain gutters, pvc pipe, stove pipe, etc... what would you use?

And then, assuming we would use some kind of bendable metal sheet like the rain gutters... What shape would the reflector be?

Finally....Would it go around each bulb, or the two-packs that typical lights have?
 

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I would use 4" pipe, cut in half. Then adjust the bulb position to perfection.

There might be a tiny increase in light if you add a "V" just behind the bulb to reduce the restrike directly above the bulb.

I feel that 4" is a good size for reflectors for T8 bulbs. If that seems too wide 3" would work too, but I would wrap a separate reflector around each bulb. I would avoid T12 bulbs due to their diameter.

Nowadays, my tanks all feature T5 bulbs... with costly Icecap reflectors. :smile:
 

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Let's say for a second that you can get mirrors on sheets of paper. No glass on them, mirrors as thick as a sheet of paper. Perfectly reflective mirrors, but next to no rigidity to the material - just like that sheet of paper. Cut-able, moldable, bendable.
I had a sheet of mylar that dissolved with prolonged contact with water. Test accordingly.
 

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If you're up on your basic physics you could design a very efficient parabolic reflector if you decide on a height for you fixture and can fix how the bulb sits in the reflector. I don't remember the formulas off hand, but I know it's not overly difficult.
 

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Discussion Starter #6
I had a sheet of mylar that dissolved with prolonged contact with water. Test accordingly.
They do warn of repeated direct water contact, but nothing about humid air (did ask, they said humidity is fine, but it degraded after a year of being rained on in an outside application in Florida). I got a sample piece to try it out, no harm in experimentation since I already own enough to make a couple of lights with. :) Should it not work, I'm going to have to finally abandon cheap lights - but I want to give this a shot!

I think I can get a decent basic parabolic shape bending a rain gutter a bit.


Thanks!
 

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Should it not work, I'm going to have to finally abandon cheap lights - but I want to give this a shot!

I think I can get a decent basic parabolic shape bending a rain gutter a bit.
No need to abandon.

White paint is a very good reflector so just paint the gutter. <For completeness: The danger of paint is that it can peal/flake.>
 

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The other issue with mylar is adhesion. Use a adhesive that can withstand the humidity as well... If the enclosure is capped with glass it can save from some but not all...

BueRam and others are good a reading between the lines. You may have well said your trying mylar on the first post. :wink:
 

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BueRam and others are good a reading between the lines. You may have well said your trying mylar on the first post. :wink:
I actually appreciate that mylar was not mentioned in the OP as the post is asking for a generalized cheap method of increasing intensity by minimizing restrike. However there are some material considerations that should be noted such as mylar behaving badly and flaking paint that could be a PITA. I like the gutter painted white myself (or PVC cut lengthwise).
 

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Discussion Starter #10
Reflective Mylar would be it. :) It is far different than what I've seen in tapes, dang it is a clean mirror.

I do have to figure out an applicator to affix it. heat and humidity play heck with most tapes, so I'm not sure about double sided tape....
 

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Discussion Starter #12
I'm learning that now as I read up. I'd never realized mylar came in sheets, had always only seen the tape adhesive backed, was hoping I'd bought something different. argh.

Heck, I'd been looking up flexible mirror. Never knew to look up mylar reflective sheet until reading the responses here, heh, even for my "discount sample" I paid too much. :icon_neut

EDIT IN:

A year ain't so bad, however, since I'm looking to budget line this for a year until my big tank is set up in the basement (Basement gets finished this year). Going to silicone bead it to rain gutter or stove pipe and roll with it.

EDIT TWO:

After reading up and thinking about what I've been exposed to...

When you guys say mylar sheeting, are you thinking like the thicknesses used to like make mylar balloons? This stuff is a lot thicker than that.... like comparing paper to non-corrugated cardboard in thickness difference..... heh, and is that going to make a difference, do you think?
 
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