Best method / compound to permanently attach rail to scope ring ?

BurtG

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  • Nov 9, 2022
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    I feel like welding will distort it. Scuff and JB Weld ?
    Not sure the best way to make sure it’s perfectly aligned. Those screws don’t that’s for sure

    4E24DE69-6DAA-4DC3-9C5E-7E5A8AB1E3C2.jpeg
     
    JB Weld would work. Another solution in a similar vein would be Loctite 660 high strength loose fit bedding compound... Have used this to bed some scope rails. Then at least medium strength threadlocker for the screws

    Whether or not welding would work is dependent on the specific aluminum alloy that it is made from. Some are difficult or impossible to weld.
     
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    I would match drill, ream, and pin the ring cap and diving board with 2 pins if I wanted to take the hard way, and if I wanted the easy way I would buy a different brand mount with a better diving board attachment design.

    If you want to cheat use some loctite retaining compound between the ring and the diving board, the above suggestion to use 660 is a good one.

    2 part epoxy needs a bit of a bond line to hold best, you could probably put 0.005" ring shims around each screw to provide that bond line gap or mix 0.005" glass beads or microballoons into the epoxy. Retaining compound would be the easier option.
     
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    But I have like 6 or 8 of these mounts.

    And used 36mm mounts never sell well.

    #shouldaboughtier1

    #zerocompromiseisalie

    #crackedlensandwanderingLRF

    To be pedantic, their name specifically says zero compromise optics. It does not say zero compromise optics, scope mounts, and diving boards... Marketing decided naming the company ZCOSMADB didn't go over well in the focus group, so ZCO it is.

    Thus, they're still in the clear, even if their diving board design is sketchy, because their name implies no such guarantee of zero compromises in the design and manufacture of their mounts and diving boards.

    I really should get an honorary MBA for this line of thinking.

    ;)
     
    I really should get an honorary MBA for this line of thinking.
    MBA = Mr. Bitch Ass

    You don’t want one of those degrees

    Lol

    Even I, a non-engineer, knows that diving board attachment method is not repeatable. Must’ve had the Someb Copramises intern design that one.

    Burt, don’t get trapped by the sunk cost fallacy.
    1729135062406.jpeg


    Although can’t you get replacement caps with their new (better) design? Sorry if this was covered in that other thread.
     
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    What about using red lock tight on the screws and then drill and tap from underneath? Too much work?

    I think you could super glue that bad boy together. I have cyanoacrylate glue (that's what's in super glue) that will do it. I have several different versions of it for my multisegment bowls that I turn on a wood lathe. Go Google about best one to secure metal on metal and see, but I feel sure you could clean everything well and glue it and it would not ever come apart, so long as you also secured those screws and they aren't already stripped, though you could probably fix that too
     
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    Reactions: BurtG
    I feel like welding will distort it. Scuff and JB Weld ?
    Not sure the best way to make sure it’s perfectly aligned. Those screws don’t that’s for sure

    View attachment 8525518
    That's the laziest design I've seen in a while!
    I'm a dumb MF'r but even I wouldn't do that.

    FWIW, here is what I would do if you have access to a vertical mill or good drill press with a compound table.

    Remove the top half of the ring.
    Screw the rail to the ring cap as usual.

    Invert the assembly and mount it into a machine vise using the rail to clamp to.
    The vise jaws should be parallel to the X-axis travel on the table so you know the rail is now lined up on that axis.

    Mount an indicator in the spindle and indicate against a flat on the exterior side of the ring.
    Tap the ring cap as needed to bring parallel to the same X-axis.

    Center the Y-axis on the existing screw holes.
    Use small center drill to spot two holes about 1 diameter inboard of the two screw holes.
    Drill slightly undersize to roughly 0.250" or 0.375" then finish ream to 0.125" dia. to the same depth.

    Blow the holes out and then tap two hardened dowel pins (example: https://www.mcmaster.com/98381A470/) into place making sure they are below flush with the interior curve of your ring cap.

    Remove the two screws holding the rail to the scope ring cap, clean the male and female threads, then Red LocTite them back in place.

    The result will be a properly aligned rail and a joint that shouldn't move.

    Put that bitch back on your rifle, zero your WMLRF and go kill shit.

    If you don't already have a proper reamer and pins, PM me you address and I will send you what you need.
    If you don't have access to a machine to do it, mail them to me. Would take about 15 minutes.

    ETA: I just now figured out Kiba was suggesting the same thing about the pins. The rail has a LOT of leverage on the small contact area of the ring cap. If you mounted a heavier WMLRF and ran very much recoil under it, I wouldn't trust a glued joint even with the better products. That's just my personal untrusting self opinion.
     
    Last edited:
    That's the laziest design I've seen in a while!
    I'm a dumb MF'r but even I wouldn't do that.

    FWIW, here is what I would do if you have access to a vertical mill or good drill press with a compound table.
    I appreciate the explanation.

    But. That’s beyond my pay grade.

    Once the wrench’s get below 1” things start to go to hell for me
     
    I appreciate the explanation.

    But. That’s beyond my pay grade.

    Once the wrench’s get below 1” things start to go to hell for me
    Priority Mail small Flat Rate box is your friend.
    My address can be found on the internet. Offer is there if you care to use it.
     
    That's the laziest design I've seen in a while!
    I'm a dumb MF'r but even I wouldn't do that.

    FWIW, here is what I would do if you have access to a vertical mill or good drill press with a compound table.

    Remove the top half of the ring.
    Screw the rail to the ring cap as usual.

    Invert the assembly and mount it into a machine vise using the rail to clamp to.
    The vise jaws should be parallel to the X-axis travel on the table so you know the rail is now lined up on that axis.

    Mount an indicator in the spindle and indicate against a flat on the exterior side of the ring.
    Tap the ring cap as needed to bring parallel to the same X-axis.

    Center the Y-axis on the existing screw holes.
    Use small center drill to spot two holes about 1 diameter inboard of the two screw holes.
    Drill slightly undersize to roughly 0.250" or 0.375" then finish ream to 0.125" dia. to the same depth.

    Blow the holes out and then tap two hardened dowel pins (example: https://www.mcmaster.com/98381A470/) into place making sure they are below flush with the interior curve of your ring cap.

    Remove the two screws holding the rail to the scope ring cap, clean the male and female threads, then Red LocTite them back in place.

    The result will be a properly aligned rail and a joint that shouldn't move.

    Put that bitch back on your rifle, zero your WMLRF and go kill shit.

    If you don't already have a proper reamer and pins, PM me you address and I will send you what you need.
    If you don't have access to a machine to do it, mail them to me. Would take about 15 minutes.

    ETA: I just now figured out Kiba was suggesting the same thing about the pins. The rail has a LOT of leverage on the small contact area of the ring cap. If you mounted a heavier WMLRF and ran very much recoil under it, I wouldn't trust a glued joint even with the better products. That's just my personal untrusting self opinion.

    I'd hedge my bets and use retaining compound or epoxy along with the match drilling and pinning that we both suggested. I meant to add the suggestion for bonding along with pinning in my earlier post. The pins alone should be sufficient, but pinning and bonding is even better, although it will make disassembly more difficult.

    And now for a brief sidetrack...

    I'm actually surprised we don't see more failures of these LRF mount diving board designs that screw into the thin upper ring cap using 2 screws with only minimal thread engagement; as Terry mentioned the stress put into the joint isn't trivial due to recoil forces because of the weight of the LRF combined with the moment arm created from mounting the LRF quite a bit above and forward of the diving board to cap attachment point.

    It was one thing years ago when people were only attaching low mass red dots to these ring cap diving board mounts, but then that design was carried over even when people started mounting far heavier LRF's to those same ring cap mounts.

    I still think Ted from ARC has one of if not the sturdiest LRF mount design with the m-brace and the serrated interfaces; the screws are only loaded in tension to hold the serrations together, the serrations take the recoil loads, and none of the loads from the LRF get imparted into the upper ring cap and scope tube as with ring cap mounted designs since the LRF bridge attaches to the mount base. I'm surprised I haven't seen any other manufacturers do something similar, but I suppose some of that is market inertia; "we've always mounted rails to the upper ring cap and we'll keep mounting them that way." Also saves the time and money to design and then tool up for a new mount with a stronger diving board attachment design.