How to install new light rod in fiber optic sight?

[JonF]

I have a front fiber optic sight on my CZ that uses simple 1mm rod. The actual rod broke (they're delicate i suppose) and i ordered some bulk length to repair it and have some on hand in the future. I noticed that the original one looked sort of peened over somehow probably by heat? How do i install the new one (i couldn't find anything in a search here or on the net)?

Jon

 

[rcmodel]

Without seeing it, I suppose you could melt the end with a small soldering iron.

Or secure it with a drop of CYA (Crazy) glue.

rcmodel

 

[JonF]

This is the model i have. Its a simple cage that supports the rod (but does not retain) at both ends.

 

[Jim Watson]

What I do is to insert a piece of rod into the blade and let about 1/16" stick out the front. I melt it into a bead with a Bic. Then I turn it around to put the bead at the rear, clip the rod to let 1/16" protrude, and melt that into a front bead to retain the insert. A drop of Krazy Glue at each post on the inside will keep it from bouncing around enough to break again. You may use up some rod getting the bead the size you want it for aiming the gun.

 

[JonF]

Thanks Jim. When heating the rod, does it want to melt and run and how do you prevent that? Hold it in a certain orientation while heating? Also, do you use anything to mash the rod down flat or does the heat/gravity take care of that?

 

[gb6491]

Here's a pdf (with photos) you might find useful: http://www.mountsplus.com/manuals/Sightlink AR15-M16 Front Sight Owner's Manual.pdf
Regards,
Greg

 

[Jim Watson]

As Greg's instructions show, if you only let a little protrude and don't heat it so hot as to catch it on fire, the surface tension of the melting plastic will draw it into a round bead.

Here is what Dawson says, although I prefer to form one bead, turn the insert around, cut to length and form the other instead of trying to get the rod to exactly the right length. Note what they say about a countersink, if your sight blade has one.
http://www.dawsonprecision.com/images/Instructions/OpticInsertInstall.jpg

 

[Riss]

My sight manual said to use one of those high temp, blow torch lighters. Keeps any soot from getting into the fiber when it melts.

 

[rcmodel]

+1
A BIC lighter will soot up the rod and turn it black.

You need to use something with a clean flame.

rcmodel

 

[Jim Watson]

Not if you don't stick the rod in the flame. You can get close enough for radiant heat to melt the plastic and bead the insert without smoking it.

 

[JRG]

I'm trying to get the old one out of the same HiViz sight as shown. I can't budge the thing, I'm thinking about drilling it out unless you guys know a better way??? I'm not trying to save it, so maybe I can burn it out????

 

[ieszu]

Is there room for you to cut it in the middle and try pushing it out that way?

Just a thought.

 

[JRG]

I tried cutting it in the middle, it almost feels like it is glued to the bottom of the steel sight frame....

 

[JRG]

Let me see if I can explain what I found out.....I melted the old fiber optics out of the sight housing. This is the same CZ housing as shown in this thread. When I finished digging out all the old stuff, here is what I found (wish I knew how to post a picture) at the base of rounded fiber optic slot is a pin just behind the front of the sight. From the bottom of the sight housing you will see the groove for the pin that retains the sight as well as the barrel bushing on the CZ. Just behind that is a little pin....this pin protrudes into the channel that holds the fiber optic, when I punched it back down I have a clear path and I'm certain the fiber optic piece will slide right in, (I don't have one yet so I couldn't actually try it) and then if you punch that pin back in, it will secure the fiber optic to the sight housing. I saw no indication that anything else secured the optics to the housing, such as heated ends, etc.

I hope this makes sense????????????????

 

[JonF]

JRG,

I understand what you are saying and perhaps that is the design of the particular sight housing you got. Mine does not have that 'feature' though. Incidentally, what model CZ is yours? Mine is a CZ75 SP01 from the CZ custom shop and they install this FO front sight as part of the custom package (CZ 75 does not come standard with a FO sight). You may want to heat the end of the rod as it causes the plastic to mushroom out and form a much larger and thus more visible tip to the rod (about 2-3 times diameter increase). the raw 1mm rod is mighty small by itself without expansion.

Also, thanks to all of the folks here lending their advice. I was able to use a simple lighter flame in close proximity to heat the ends and was amazed that they just flatten out nice and smooth and not just sag down.

 

[JRG]

JonF, mine is the PCR and the sight came from HiViz out of Colorado, so I'm sure you are correct in saying the two housing are different although they look a like. When I get my rods I will heat the ends as you suggest. Thanks for the input.