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  1. #1
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    Default Design process of VNI R4/Galil upgrade kit

    I felt it would be interesting to share the thinking behind the design process of a part in a hopefully digestible format. Take note this is thousands of hours and correspondence shrunk down to a few paragraphs.


    We’ve been working on a full length picatinny rail for the R4/Galil series of rifles for about three years. It’s a subsection of a larger project I decided to prioritize because the prototypes worked incredibly well and I know this something that users have needed for years.


    First design – 2017
    I don’t have a picture of this anymore, but the first version was essentially a side rail like that of the AKM, but it inserted and locked in vertically instead horizontally. We scrapped that design because it had too many parts. Never went beyond design stage.


    Second design – 2018
    Marked in the pictures. We decided that since the Galil already mounts the rear sight on the dustcover and that it is thicker than that of the AK, it can be used as a base. We went through an entire analysis of where the weak point in the dustcover is and it is at the front where it slots into the gas tube. It would make sense to use the gas tube as a base and somehow lock the dustcover to it. It was initially decided to go with a hinge – similar to that of the AKSU-74. The most suitable hinges we could source were made for suitcases. We eventually scrapped that design because the compact hinges were prone to damage and the larger hinges weren’t stiff enough. Installation time was also deemed excessive.


    Third design – 2018
    We found a vastly more efficient way to mount the rail to existing rifles. Installation with specialized tools would be down to a few minutes. Rear rail locked into the front rail via a slot. Tested rail repeatability and I was able to get 5 MOA with my LM5 with no POI shift when removing and reinserting the dustcover. We did however determine that the portion on the rear rail sticking out like that was a weak point for when dropped.


    Fourth design – 2019
    Marked in the pictures. Since the design worked, we’ve been able to focus on improving smaller things. With A we tried internal lightening cuts for weight savings. Scrapped because I felt it looked to fragile and it and saved only a negligible amount of weight. With B we did the cuts on the outside. Scrapped for the same reason. C is the final version we printed a test copy to see what it looks like on a rifle. There version now currently being manufactured differs only slightly – the biggest change being that we’re adding a 1.5mmx1.5mm cut in the rear rail to double up as a rear sight leaf for when fitted to a Type 56 or an AK variant without the strengthening ribs in the dustcover (still under development).

  2. #2
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    Default Re: Design process of VNI R4/Galil upgrade kit


  3. #3
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    Default Re: Design process of VNI R4/Galil upgrade kit

    I decided to create one length for both the short and long barreled versions. On one image I marked on a prototype where you can see the slot at which point you would need to cut for it to fit the shorter rifle, or if you want a shortened version on your full length rifle.

    The picture of the C version on top of a Galil SAR is incorrect. Even though the rail can fit on top, the vent holes on the gas tube would heat up the rail. Does look cool though.

    I had to blur out the parts which are not design protected yet. My patent attorney would not appreciate my actions otherwise.

  4. #4
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    Default Re: Design process of VNI R4/Galil upgrade kit



    Pictures of the hinges. I spent way too much time on trying to imagine a suitcase hinge into a piece of precision equipment.

  5. #5
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    Default Re: Design process of VNI R4/Galil upgrade kit

    Following - well done!!

  6. #6

    Default Re: Design process of VNI R4/Galil upgrade kit

    Thank you for sharing.

  7. #7
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    Default Re: Design process of VNI R4/Galil upgrade kit

    One thing I really don't like about the existing fitment of rail kits on the LM series is the insistence of bending the charging handle or screwing an attachment to it. Granted you can't leave it as-is, but it's a lot more effective to just purchase and install a newly-made horizontal bolt carrier as a lot of people are doing in the States. I'm making a point of sourcing those as well. It just looks and works better.

    PS - The picture below is not the same. Those I'll be using are 8620 forged tool steel and a black oxide coating. These are just for illustrative purposes.


  8. #8
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    Default Re: Design process of VNI R4/Galil upgrade kit

    Another aspect of the design - installation tools. If you're meant to be able to install a set in a few minutes, you need specialized equipment. The most obvious one I can talk about currently is the centering tool. If you think about it, how would a gunsmith to put a rail on top of your rifle and ensure it is 100% centered before installation? The logical choice would be a bubble level and a bunch of clamps correct? We installed the prototype that way, but it was felt it took too long. We developed a small tool to simplify it. I'll post a few pictures tomorrow.

    Out of curiosity, how do you think you'd approach this problem?

  9. #9
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    Default Re: Design process of VNI R4/Galil upgrade kit

    Quote Originally Posted by VNI View Post
    Another aspect of the design - installation tools. If you're meant to be able to install a set in a few minutes, you need specialized equipment. The most obvious one I can talk about currently is the centering tool. If you think about it, how would a gunsmith to put a rail on top of your rifle and ensure it is 100% centered before installation? The logical choice would be a bubble level and a bunch of clamps correct? We installed the prototype that way, but it was felt it took too long. We developed a small tool to simplify it. I'll post a few pictures tomorrow.

    Out of curiosity, how do you think you'd approach this problem?
    Well this is what the centering tool looks like:



    I've also got the link to the Grabcad file for anyone who might want to check the model.

    https://grabcad.com/library/galil-rail-centering-tool-1

    It prevents the installer from having spend quite some time trying to carefully use a level to center the front rail before installing it into place. With the front rail installed using this, the rear rail can be installed.

  10. #10
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    Default Re: Design process of VNI R4/Galil upgrade kit

    What material are you 3D printing out of?
    Is it rigid enough to be repeatable?

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