Whats your technique for removing shear pins?

Locksmith

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I have to use very short shear pins in my avbay due to how my gopro is mounted inside :facepalm: so I can only remove them from the outside. And after every use I have to fight and fight and FIGHT, Im literally typing with a bloody thumb since I had been using a tiny flat head sharpened to a razor, But after it went threw my thumb Im done with that thinking disposable PEM nuts is my next route.
Any ideas?
Thanks
 

mccordmw

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Remove after they've done their job and are now broken? I have a tiny screwdriver I put on it and then smack the back end to pop it out.
 

watheyak

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A drill bit slightly smaller than the shear pin chucked up in a pin vise. I kinda drill them out slowly by hand and they either crumble or twist through.
 

Nathan

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The half of the sheared nylon screw with the head gets pried out with my fingernails. The other half gets poked out with a very small screwdriver.

But what do you do about the nosecone shear pins that you poke out of the shoulder? After 17 flights the nose cone of my Frenzy XL now has 51 sheared nylon screw tips rattling around inside.
 

rharshberger

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When I use shear pins the head side of the two tubes is hardened and threaded so a screwdriver simply turns them out, the inner tubes shear pin hole is drilled to be a slip fit for the shear pin (my shear pins are all nylon screws). The inner sheared off piece is pushed thru or it falls inside after shearing, a dental pick is useful for pushing them out. As for that nose cone a hole drilled in the bulkhead or side of shoulder will allow them to be dumped out.
 

kcobbva

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I stick the tip of my Xacto knife into the pin and then unscrew them. Normally works, sometimes not so nice.
 

RocketFeller

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I stick the tip of my Xacto knife into the pin and then unscrew them. Normally works, sometimes not so nice.

That is what I do as well. One thing that seems to help is a little bit of beeswax on the screws prior to installation, it makes them screw in and out smoothly.
 

dixontj93060

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For the past five years or so I've been using end flush cutters. You can get them at a jewelers supply or better, in a cheap multi-tool pack at Lowes or Menards. They are fabulous! Simple, fast removal with no scratching of the finish.

ImageUploadedByRocketry Forum1492266837.724154.jpg
 

Locksmith

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thanks for all the advice, today I tried using new xacto knife blade and heated the tip up with lighter and inserted it into the bolt and let it melt itself a notch and unscrewed it, worked pretty good got 5-6 out 6th the pem popped out. I do like the idea of trying wax on bolts. Will also try the small drill bit idea.
 

dixontj93060

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Oh, sorry, missed these were already sheared, i.e., without heads. My suggestion would be to make the holes press fit versus a tight, thread fit. Then after use they just slip/pop right out.
 

Random Flying Object

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Heat a small slot screw driver with a lighter, push the hot screw drive tip into the remainder of the nylon screw and unscrew.
 

OverTheTop

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You could get some small left-handed drill bits and just drill them out with a hand-held pin vise or something similar. At some point as you are drilling they will start to unscrew probably.
 

Steve Shannon

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Oh, sorry, missed these were already sheared, i.e., without heads. My suggestion would be to make the holes press fit versus a tight, thread fit. Then after use they just slip/pop right out.

That's best. There's nothing to be gained by cutting threads in either layer. I have threaded the outer layer and left the inner layer just large enough for a slip fit, but I would never thread the inner layer unless I felt I needed to be punished for something.
Now, I'll always make the outer layer a slip fit and the inner layer an interference fit. That way, as you note I can just press the pins in and push them out.


Steve Shannon
 

Crazyrocket

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That's what I do, simple press fit. I usually need something flat (such as the side of a blade) that I can press the shear pin into the hole. If I use my finger, then sometimes the shear pin bends and I have problems getting it installed. Never had any problems and easily pushed out after the flight.
 

Handeman

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I never thread holes for shear pins. The head end is usually missing or pulled out easily with fingernails and the inner parts are bouncing around inside. If not, they push through when the next shear pin is pushed in. I don't spend time and energy on removing the old pieces.
 
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