fiber optic, limits?

dottorfoggy

Member
Today weather is joking, so I decide to play and understand the optic fiber.
The first question is, about the limit on dimension
What's the limit on sight dimensions? This gas pro is 2cm long
What's the limit on the optic fiber length?

Here a picture on what I have now, next week will be the first competition for me outdoor and I'm little bit afraid to be in the rules sizes

WP_20170508_20_10_51_Pro.jpg

WA web site talking on 2cm max on the sight, but means the total length of the fiber too?
 


bimble

Well-known member
Supporter
Fonz Awardee
Ironman
no, the 2cm is straight out from the sight (so, imagine a single 2cm long fibre pin), but if it curves around like that it's fine, because it's not straight.
 


bimble

Well-known member
Supporter
Fonz Awardee
Ironman
Some (having looked for some images), this is totally legal



but this IS limited to 2cm in length, because it is straight

 


Rik

Supporter
Supporter
The wording in the rules is pretty clear, it says about the sight tunnel:
The overall length of the sighting circle or point (tunnel, tube, sighting pin or other corresponding extended component) shall not exceed 2cm in the line of vision of the athlete.
and about the sight pin a couple of paragraphs further down:
The sight point may be a fibre optic sight pin. The total length of the fibre optic pin may exceed 2cm, provided that one end is attached outside the athlete?s line of vision at full draw, while the part within the athlete?s line of vision does not exceed 2cm in a straight line before bending. It can only provide one illuminated aiming spot at full draw. The fibre optic pin is measured independently of the tunnel.
 


Rik

Supporter
Supporter
It gives you a glowing dot (light gathered through the fibre is directed to the ends). In theory a longer fibre will give a brighter dot - within limits.
 


KidCurry

Well-known member
I'm curious. How does the fiber work, what benefit does it offer?
The length of fibre wall allows light to pass through the wall where it gets trapped inside until it bounces it way to the end where it escapes creating a bright dot. The longer the fibre the brighter the dot. I find they work better outdoors where light levels are higher, not so good indoors. It's just a matter of preference if you prefer a bright dot or a dark dot against a target face.
 


bolerus

Member
old thread i know, but i have just bought a beiter flo pin, and to be honest i am not impressed, no where near as light as a friends spigerelli one. so i was wondering if any body knows of anywhere that sells length of the material, so I can make a custom length one, ( bent 2 cm out to hide behind the sigh to stay legal)
 


KidCurry

Well-known member
Hi Geoff, Bolerus
Be careful here. I was looking for fibreoptic cable a couple of years back as I found the original TenZone fibre gets very brittle after a couple of years. Most fibre optic cable is really bad at absorbing light through the coating. You need an optical fibre that is designed, or at least these characteristics and, I think, are referred to as florescent optical fibres. They have a florescent doping as far as I can tell. Could not find a supplier outside China or the USA.
The best websites I found were in the states...

http://www.fiberopticproducts.com/Archery.htm

or

http://www.i-fiberoptics.com/fluorescent-fiber.php

 


geoffretired

Supporter
Supporter
Cheers for that. My biggest problem was getting a nice bright blob to form on the cut end. Too much heat and there are bubbles that make it dim. More heat than that and it shrinks and burns. Heehee
 


bolerus

Member
Thanks for that kidcurry. I notice they sell by the metre. Wonder if any body would complain if I had a long strip down the front of the riser. I think I will buy some and experiment. I see they don't seem to have the 2.5 mm that my beiter insert takes... I do have one of those imitation titan sights that lost its pin... Think it's 1.5 mm.

Experiments incoming I think
 


jonUK76

Member
old thread i know, but i have just bought a beiter flo pin, and to be honest i am not impressed, no where near as light as a friends spigerelli one. so i was wondering if any body knows of anywhere that sells length of the material, so I can make a custom length one, ( bent 2 cm out to hide behind the sigh to stay legal)
Which colour Beiter pins have you tried? I've found the red glows OK, the orange barely at all. The green glows, but I don't find it gives great contrast with the target. Haven't tried the blue or black pin.
 


bolerus

Member
Just the red. I haven't shot it yet. I heated it and bent it 90degrees after 20mm to hide it behind the pin, I'm wondering if that was to much of a bend as it definitely seemed brighter before. I have ordered some violet and some green from one of those sites above. I think they come as a yard of each so I'll be cutting them and experimenting. Will try for a long piece with a gentle bend.

We will see )
 


KidCurry

Well-known member
Just the red. I haven't shot it yet. I heated it and bent it 90degrees after 20mm to hide it behind the pin, I'm wondering if that was to much of a bend as it definitely seemed brighter before. I have ordered some violet and some green from one of those sites above. I think they come as a yard of each so I'll be cutting them and experimenting. Will try for a long piece with a gentle bend.

We will see )
If there is no other specification, the bend radius for optical fibre is usually 15 x the diameter. Heating may well have damaged the fibre structure.
 


AJBrady

New member
Which colour Beiter pins have you tried? I've found the red glows OK, the orange barely at all. The green glows, but I don't find it gives great contrast with the target. Haven't tried the blue or black pin.
Unfortunately the black pin is only available in 1.5mm x 1.5mm. You really need the 2.5mm pin to take full advantage of the black light.
 


bolerus

Member
The 2.5 mm is quite thick,. Couldn't think of any other to bend it.

What other options are there? I imagined just bending would break it
 


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