What epoxy or polymer filler matl to use?

Discussion in 'Gunsmithing Forum' started by busykngt, Jan 20, 2013.

  1. busykngt

    busykngt New Member

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    I'm looking to install a Picatinny rail on the underneath side of my new Marlin XT-22RZ (a bolt action, threaded barrel .22LR). It has a polymer {plastic} stock. The Picatinny rail will be used to attach a bipod. The fore arm is pretty much hollow space - it does have some 'molded in' bulkheads ever couple of inches down the length of the fore arm and a rib/bulkhead that runs lengthwise down the bottom of the fore arm channel.

    The long rib is centered in the middle of the fore arm channel and maybe 1/16" thick. And of course that's exactly where I will be drilling the two holes to mount the Rail (fore & aft). So, between the perpendicular supporting bulkheads and this long one running down the middle of the channel, I'm left with, what basically are four little compartments or chambers that I'm looking to put some kind of "filler" material in.

    So....finally, my question: The filler material needs to harden and be able to be drilled through (to support the mounting bolts of the Picatinney rail). What type of resin can/should be used for this? (I'm looking for name brands and/or where to buy it). :confused:

    I'm sure gun smithing folks run into this often - but I'm fairly new at having to try something like this. [Also: the Marlin molded swivel shape makes a bipod swivel mount unusable, just in case you were about to suggest that path]. Any suggestions will be much appreciated!
     
    Last edited: Jan 20, 2013
  2. c3shooter

    c3shooter Administrator Staff Member

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    All else fails- JB Weld.

    jbweld.jpg

    Give it a couple of days to cure completely, you can drill it, tap it, machine it, etc. Cheap and readily available- but is NOT a "fast cure" product.
     

  3. hiwall

    hiwall Well-Known Member

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    They do make JB Weld in a fast cure(5 minute) but the original slow cure (like pictured) is much stronger.
     
  4. Axxe55

    Axxe55 The Apocalypse Is Coming.....

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    J B Weld would be the one i would have suggested as well. make sure all your mating surfaces are very clean. degrease and also clean with alcohol as well. no matter how strong an adhesive is, it won't bond properly unless it's clean.

    Hiwall, the JB Weld Quik is crap! i used some in the past, and won't ever use it again. only the slow curing original JB Weld.
     
  5. Renegade44

    Renegade44 New Member

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    Have you ever messed with a plastic welder? They are easy to use. It may work for your situation
     
  6. JSStryker

    JSStryker New Member

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    Might want to also rough up the surface just a little to make sure the JB Weld gets a good grip on the stock.
     
  7. Axxe55

    Axxe55 The Apocalypse Is Coming.....

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    excellent point! sometimes when you do somethings so many times you forget some of the finer details.
     
  8. BillDeShivs

    BillDeShivs Member

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    Why not just drill through and use machine screws and nuts on the inside of the forearm?
     
  9. Axxe55

    Axxe55 The Apocalypse Is Coming.....

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    another option would bethis Boyd's laminated stock already has two front sling swivels for using a bipod.

    RIMFIRE HUNTER MARLIN® XT CLIP SERIES HEAVY BARREL CHANNEL STOCK PEPPER LAMINATE (FINISHED)

    priced at $92, it's a good deal. even if you secure the rail for mounting the bipod, the forearm is still going to have a lot of flex. i used one very similar to this on my Savage M93r17 and it's a great stock for the price. i have used them on another rifle as well. Boyd's is what i would suggest instead of trying to modifying the factory flimsy stock.
    www.boydsgunstocks.com
     
  10. srtolly1

    srtolly1 New Member

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    I would ask "what will you be using the gun for"? The conditions you will be using it in can influence how you handle the situation. Boyds makes great wood stocks but extra care may be needed in damp environments. Synthetic stocks are better there. I used JB weld in my Mosin Nagant stock to bed and reinforce some spots.
     
  11. busykngt

    busykngt New Member

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    That thought had occurred to me and I decided since I would be cutting (drilling) through the main longitudinal support rib in the stock’s fore arm, it might weaken too much. I haven’t put the calipers to it, but the polymer thickness of the fore arm in that area appears to be about 3/32” (more than a sixteenth but less than an eighth inch). Maybe that would hold up okay for bipod use? I was thinking if I reinforced the rib (which would actually be drilled through in two locations), it would make that part of the fore arm more stiff and I’d see no negative effect from having done so (not to mention the area being more “beefed up” to support the bipod).

    Renegade44, I tried my hand at plastic welding exactly one time and that was almost thirty years ago. So yes, I’ve “technically” done it but don’t have access to such a welder now (AND probably lack the necessary skill level). As I recall, I did okay with it and it was fun to do but I was hoping I could just mix up a couple of chemicals, fill in the little chambers, let cure and be done with it.

    I appreciate the JB Weld recommendations - I’m familiar with that. Left to my own devices, that’s pretty much what I was “defaulting” towards. I’m thinking the compounds used for glass bedding would probably be too brittle to drill through (and I suspect it may not be as strong as JB Weld). But I wanted to see if anyone had something new or different that might do an even better job.
     
  12. hiwall

    hiwall Well-Known Member

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    Another stronger possibility is cut out some of the support ribs. Lay a piece of steel in the forearm and cover under and on top of steel with the epoxy, Then drill and tap the holes thru the plastic and metal.
     
  13. Axxe55

    Axxe55 The Apocalypse Is Coming.....

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    laminate stocks are more resistant to water and moisture than typical wood stocks, hence the reason i mentioned the Boyd's laminated stock. plus they can be sealed as well which will make them just as good as a synthetic stock.
     
  14. busykngt

    busykngt New Member

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    Sincerely: thanks guys for the suggestions! :)

    axxe55, this little 22 only cost me brand new, $210 (delivered & FFL) so I'm not inclined to spend another hundred bucks (once shipping or tax is included) on it. Please take no offense at this because otherwise, it's not a bad idea. Along this same "replacing the stock" thought was my original stubbornness and mindset of wanting to make the cheap Marlin polymer stock work! In my opinion, Marlin already screwed up by molding in such an unconventional sling swivel shape as part of this stock (the rear swivel is the same triangular shape). That(!), as much as anything, made me want to figure out a solution to work around this problem.

    And hiwall, I'm liking that idea of yours, mucho! That would keep me from having to "gob in" the JB Weld (which is made about 70 miles east of me). And a metal plate, with two holes drilled and JB Weld'ed in place, would sure support the Picatinny rail permanently. (Not even sure the holes need to be tapped since there's room for nylon lock nuts). Looks like that's the direction I'm headed. Thanks again everyone.
     
  15. Axxe55

    Axxe55 The Apocalypse Is Coming.....

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    my Savage wasn't much more when bought it new eight years ago. paid like around $250 as a combo deal with a scope. just got to the point a few years ago that i was fed upwith the factory stock and just went ahead and bought the Boyd's laminated stock. best decision i ever made for the rifle. it made a world of difference in how it felt when shooting it. nothing wrong with doing it the way you want to, just trying to save you some time. in a couple of years, you might even wish you had just went and bought the laminated stock in the first place. i know i did! but good luck with your project.