kydex-like plastic??

I wouldn't of thought this, but finding kydex or similar plastic material is turning out to be the hardest part of the project. I have checked every local "Lowes-Depot" store, and found nothing. I even checked a couple craft stores. You would think since this day and age everything is made with plastic, it would be easy to find.

What are people using for thier UTAs? I need a sheet of black pastic roughly 6ft long by 24" wide. Suggestions?

Thanks,
Tim

Tim,

Try looking for a plastic supply company in the yellow pages.

People speak of kydex like it's holy. It's not. It is unnecessarily heavy, often hard to find, and not cheap when you do.

What is it's function? To block external light? Any opaque material will do that.

As reflection reducing flocking? Remember the tests done here a while ago... it was quite a scientific affair and kydex was at or near the worst of the potential materials.

Is it light? Nope.

Is it weather proof, yes, they say it can warp in the sun/heat, but come back to its shape...

I thnk the reason KB push it so much is that it is an all-in-one solution. Tough, looks good outside, not bad for reflections inside (but really not great, not like velvet or anything) and moisture proof.

Use anything you like then flock the inside. One suggestion I have would be a roll of wood veneer and put that flocking paper on the inside. Or do the same with any light or freely available plastic you have. People have even used formica, but I prefer the lightest thing I can find plus the best flocking I can get. Mine combo came out lighter than kydex (1/10th weight thin polyethlyne) and better flocking (that black velvet that won the test here --- name escapes me) to boot.


Question everything.

TomL

They make a 1/16" sheet of ABS that looks just like Kydex, but it is much cheaper.Cost me $20 for a 4'x8' sheet in black. This is great stuff and is more stable I am told than Kydex.
Here is a picture of a light baffle made of it for a Night Sky 14.5".
I bought it at a place called Bakersfield Plastics.

Attached Image:

I am at the same stage of building a 16" Dob, and I have the same problem. I am in the process of gluing 3 sheets of wood veneer together using contact cement. Then I plan to coat the inner and outer surfaces with polyester fiberglass resin to give it more strength. I then plan to line it with McMaster-Carr's black felt with adhesive backing. I hope it all works. I've used the black flocking material with superior results on another telescope.

Demetrios

Hello:
I ran into this problem too. I found some plastic "for sale" signs at Walmart for a few bucks, spray painted them black, and nailed them into the top end (glue would also work). This works fine for me. For extra light supression, I put a patch of black velvet opposite the focuser. As mentioned before, the plastic on the top end is for light supression, so anything that's opaque, flexible, relatively weather proof and cheap will work.

Cheers
Mike Connelley