Author Topic: Casting clear light pipes- material ideas?  (Read 2683 times)

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peteski

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Re: Casting clear light pipes- material ideas?
« Reply #15 on: April 13, 2017, 01:00:14 AM »
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Didn't you just make a Seinfeld reference in another thread recently?

Um, I do remember that but I don't think it was me - but maybe it was . . . and I'm just having a senior moment.
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peteski

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Re: Casting clear light pipes- material ideas?
« Reply #16 on: April 13, 2017, 01:03:00 AM »
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hey John...have you thought about possibility of nylon (acoustic) guitar strings, heating the tip just as you would with a fiber optic rod? just thought.
Gary

Nylon (fishing line or guitar string) is not really crystal-clear. Usually it has is slightly milky (which would attenuate the light. But many that would be a desirable property?
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Lemosteam

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Re: Casting clear light pipes- material ideas?
« Reply #17 on: April 13, 2017, 09:19:29 AM »
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hey John...have you thought about possibility of nylon (acoustic) guitar strings, heating the tip just as you would with a fiber optic rod? just thought.
Gary

Gary, that's a great idea, but I think Pete is right.  I'm instrumentally deficient anyway.  :D

Philip H

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Re: Casting clear light pipes- material ideas?
« Reply #18 on: April 13, 2017, 09:57:27 AM »
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so color me clueless - or under caffeniated - but if you are going to order materials to cast . . . then why not order more fiber optics and be done with it?
Philip H.
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SP-Wolf

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Re: Casting clear light pipes- material ideas?
« Reply #19 on: April 13, 2017, 10:42:27 AM »
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Sorry,

Thought I was helping.

Wolf
« Last Edit: April 14, 2017, 09:20:55 AM by SP-Wolf »

Lemosteam

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Re: Casting clear light pipes- material ideas?
« Reply #20 on: April 13, 2017, 08:46:51 PM »
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All of the material I need are local.

This is really an inexpensive experiment, that if it works I can make other types of light pipes not suited for fiber optics. If not, well I tried.

While I appreciate all of the comments very much, my original post was to find materials that I could use within the constraints I mentioned. I did not ask for other ways to do it, as those are quite obvious.

dougnelson

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Re: Casting clear light pipes- material ideas?
« Reply #21 on: April 18, 2017, 07:43:27 PM »
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Hi John:
I have made "fiber optics" out of clear styrene sprue.  Heat over a candle and you can stretch it to the desired diameter.  You actually wind up with a tapered shape, so you can cut it at the correct diameter point.  I used this technique for my Baldwin transfer unit very successfully.  You can also finish it off by making a lens from MS Kristal Clear.

Lemosteam

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Re: Casting clear light pipes- material ideas?
« Reply #22 on: April 18, 2017, 07:57:10 PM »
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Hi John:
I have made "fiber optics" out of clear styrene sprue.  Heat over a candle and you can stretch it to the desired diameter.  You actually wind up with a tapered shape, so you can cut it at the correct diameter point.  I used this technique for my Baldwin transfer unit very successfully.  You can also finish it off by making a lens from MS Kristal Clear.

Yep, but as an experiment, this concept could lead to things like the windshields for your C Liner, or a light pipe for numberboards. I just need a design that I can copy and a material that is reasonably translucent.

peteski

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Re: Casting clear light pipes- material ideas?
« Reply #23 on: April 18, 2017, 08:58:11 PM »
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Yep, but as an experiment, this concept could lead to things like the windshields for your C Liner, or a light pipe for numberboards. I just need a design that I can copy and a material that is reasonably translucent.

What I don't understand John is your aversion of using crystal-clear urethane or epoxy resins which are specifically designed for this task.  Yes, they have to be mixed, but I really don't see any other viable alternative which will produce the desired quality parts.

Any other 1-part clear substance will not work due to the need for open surfaces (to evaporate the solvent, and to shrinking due to evaporation of the said solvent). One exception might be the scale "water" ( I think Woodland Scenics makes) which comes in granules which are heated to melt, then poured as a liquid which hardens as it cools (so no shrinkage due to solvent evaporation). But it is probably too viscous to be used in small molds and IIRC it has a slight amber tint.
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craigolio1

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Re: Casting clear light pipes- material ideas?
« Reply #24 on: April 25, 2017, 04:09:56 PM »
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I've wondered about a home made poor mans injection molding set up. I was at an electronics store a few years back and saw some cyringes with "needles" that were larger diameter but still rather small in size. Maybe they are for precision lunricating? Anyway, you could make a nice strong and well supported mold, make sure it has an exit for the air to leave, and a tiny access hole for the "needle", use whatever clear thing you need to inject (maybe the Woodland Scenics stuff mentioned above) and then you force it into the mold.

I'll try and find them in line.

Craig

Edit.

Actually depending on complexity of the shape you might be better off having the material in some kind of funnel set up tonfee into a hole by gravity, and then you could have exits at the ends of any odd spots, and then use the syringe to draw the air out, which would cause the liquid to be drawn in.

Here's one example.

http://eclipsetools.com/products/syringe-pack-3-per-pack/?doing_wp_cron=1493151243.9221999645233154296875
« Last Edit: April 25, 2017, 04:18:40 PM by craigolio1 »