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How to bend plastic optic fiber ? Answered

Hi, I have 0.75, 1 and 1.5mm plastic opic fiber that I am using for my project (which will be the topic of my first instructables ;) ) I need a way to bend the POF in right angle. I don't care if the bending raidus is not very important (spec says max radius is 10 time diameter, 15mm radius is ok for me, and I don't care if I loose a little brightness). I want the POF to stay bend after I have bent it : it must keep the curve I gave it for at least 24 hours. I manage doing something not so bade (but really time consuming) by heating the POF with an hair dryer. I wander if anybody has a better tested idea ? (in the meantime, I'll try putin it in boiling water to see if it kep the shape once cooled). Regards, tReg.



11 years ago

. The first thing I thought of was a hair dryer. If that doesn't work, maybe you can slip the fiber inside of a piece of metal tubing and then bend. . A quick search for "bending fiber optic" and "forming fiber optic" didn't turn up anything that looked promising, but I didn't dig very deep.


Reply 11 years ago

the metal tubing could have been a good solution if I did not have more than 200 fibers to bend (all of them must be bent in differet places, so using a a large tub is not an option). For now, my best solution is boiling water, I heat the fiber for a few second, then I can bent it on a very tight diameter, and the angle stay about the sme when it cools. The problem is that I have to bent is on a very short radius, or the fiber takes its shape back before it cools. I also tryed to roll the fiber (when hot) on an aluminium 6mm diameter tube, and put it in cold water. It seems to work, but it is not very easy to get the 90° angle I need. Anyway, I think this instructables is going to be fun, I'll keep you informed. If someone have other ideas, let me know :) Regards, tReg.


Reply 11 years ago

Ok, I think that I hav found the solution : -You have to separate the fibers, making on group for each diameter of fiber -Put the fiber in boiling water for a few seconds (10 for 0.75mm, 20 second for 1.5mm) -Also put a 6mm aluminium tub in the boiling water -Wrap the fiber around the tub : 5/8 of turn for the 0.75 fibers, 4/8 of turn for the 1mm fibers, and 3/8 of turn for the 1.5mm fiber -Maintain it like this during a few seconds in cold water This will not give exactly a 90° angle, but is will be close enough and suit my needs ! (I hope I'm not the only one who like optic fiber, leds, concrete and rainbows, beause this instructable will take ages to write :) ) tReg.


Reply 3 years ago

Hmm, I sued this method back in the day:
Hot air gun at medium heat pointed at some heat resistant stuff like cement sheeting.
On there and in the center of the hot air flow a pin with the diameter of the bend you need, for multiple just add more pins and move the sheet around ;)
Now you hold the fibre in the hot air flow and start pulling the ends around the pin with very little force.
You will see and feel when the temp is just right as the stuff then bends like a warm candle.
Hold in place and move the sheet out of the heat and a few sec later all is good.
If you need specify angles make some marks on the sheet and make the angle(s) you need about 5° smaller, so for 90° you use 85° and so on.
Makes mass producing far less time consuming ;)


3 years ago

methinks i hath a solution good sir! i recently made a Fallout pipe rifle replica, and for it im making a reflex scope, well i bought fiber optic rods and i have used fiber optic rods in the past. if you hold it near a flame, say a candle (so u have both hands free) then it will heat up and you can set it into a pre made set, like a wooden board with nails in it, so the rod cools into the shape u need. thats what ive always done, and while the thickness of your rods are less than the 1, 2 or 3mm i usually work with, im quite confident that the youll get the same results. try holding the 0.75mm near the flame for 3-4 seconds and add 1-2 seconds for every 0.5mm increase in thickness.