Remove e-match protective caps or leave them on?

Discussion in 'Techniques' started by Curtis Enlow, May 11, 2019.

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  1. May 11, 2019 #1

    Curtis Enlow

    Curtis Enlow

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    It seems the obvious answer is to remove them, but I would like to know what others do (and why).

    thanks!

    C
     
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  2. May 11, 2019 #2

    NateB

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    I leave them on as much as possible. The end of an ematch can be sensitive to friction and lead to an unintended ignition. While I haven't seen an ematch ignite from friction when inserting it in a device first hand, I have treated a burn injury when someone was removing an ematch without the shroud and the device ignited in their hand.
     
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  3. May 11, 2019 #3

    Eric

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    The Caps stay on until I start making charges. I build my charges in a glove fingertip. So the cap comes off as soon as it's ready to go in to the black powder. For CTI motor ignition matches, I leave the cap on until I'm out at the pad.
     
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  4. May 11, 2019 #4

    Steve Shannon

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    When I first started I took them off, but now I leave them on when using them. They act as a strain relief for the wires and help direct the flames and hot gas.
     
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  5. May 11, 2019 #5

    mpitfield

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    I cut mine roughly in half. They are still covered but the head is basically flush with the end of the protective cap.
     
  6. May 11, 2019 #6

    prfesser

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    Common plastic soda straws (regular size) fit perfectly over the cap. If memory serves, about 1 1/4" of 4F BP in the straw is one gram (please CHECK don't take the word of an absent-minded professor!! Well, former professor, emeritus and all that :)). Insert ematch/cap in straw, scoop up BP til you get the right amount, cut straw, tape over end and for good measure, tape the cap to the straw.

    Best -- Terry
    Doing my best to pass knowledge to others. If only I could pass wisdom... ;)
     
  7. May 12, 2019 #7

    Mhight

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    +1
     
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  8. May 12, 2019 #8

    markjos

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    The only time I remove the protective cover is if I'm inserting them in the bottom of a small microcentrifuge tube - they just consumed too much space. Otherwise I leave them on, whether they're in charge cups, glove tips, cardboard tubes. When I first used them, years ago, I assumed they should be removed, but no.
     
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  9. May 12, 2019 #9

    Curtis Enlow

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    I should add that I will be using them in centrifugal caps, drilled in the ends, hot glued and the 'cap' down in the cup.

    It sounds like trimmed but left in place is the best & safest approach.

    thanks, everyone, for your responses!

    C
     
  10. May 12, 2019 #10

    JohnCoker

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    +1

    I also put a bit of epoxy on the wire and pull it into the cups; that way the trimmed cap base is against the bottom of the cup with epoxy and the match head protrudes above the cut cap.
     
  11. May 12, 2019 #11

    davdue

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    Learned something new. I have always removed them. All my rockets either have a CPVC cap or a copper pipe cap for a charge well. They have a screw holding them to the bulkhead so I have always folded up a piece of blue tape and put it over the screw before I thread the ematch through the hole in the side and pack the 4F BP in it. I have always thought the cap would hinder the charge. I guess not. Thanks for the question OP
     
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  12. May 12, 2019 #12

    blackjack2564

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    Remove, they take up too much space in my charge holders.
    I do leave them on when making small charges utilizing straws.
    Straws I have are perfect fit over the caps, bit of tape & done. Mostly less than .4 gram separation charge [2-stage]
     
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  13. May 12, 2019 #13

    OverTheTop

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    I remove them, and then put a small piece of heatshrink on the back half of the eMatch to ensure they don't short out on the aluminium charge holders.
     
  14. May 12, 2019 #14

    Bat-mite

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    Always remove.
     
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  15. May 13, 2019 #15

    jd2cylman

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    I take them off then cut them in half, so the back side covers the metal part to prevent shorts.
     
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  16. May 15, 2019 at 4:37 PM #16

    ozwald

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    I always leave mine on and inverted to face the bottom of the charge well ?
     
  17. May 15, 2019 at 5:17 PM #17

    Nytrunner

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    I leave them on since I use metal charge wells, but on smaller wells (like 38 special casings), I remove the cap and use electrical tape over the exposed chipboard at the base of the match head.
     

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