Friday, January 11, 2019

T19 Build Guide - Part 4 - Stock Assembly

Previous: Part 3 - Breech Assembly

  • Hand Drill Motor
  • 9/64" Drill
  • 7/64" Drill or 6-32 tap drill size to suit material
  • 3/16" Drill
  • 6-32 Tap
  • 10-24 Tap
  • Tap Handle
  • Means to cut 1" PVC pipe square (miter/chop saw, wheel-type tubing cutter, miter box and handsaw, ...
  • Knife
  • Mini Grinder/Zip wheel
  • At least 4" length of 1" IPS PVC pipe. You may use Schedule 40 or 80 in pressure-rated or electrical conduit type; which sort of pipe used is mostly about color coordination with your build.
  • 2-part methacrylate adhesive (Devcon Plastic Welder or equivalent)
  • T19 Stock Base
  • T19 Stock Body, charge or non-charge version
  • T19 Stock Buttplate
  • 10-24 1" length socket head cap screw (SHCS) x 4 (Stock base to drive housing)
  • 10-24 3/4" length SHCS x 2 (Stock buttplate to stock body)
  • 6-32 2" length SHCS x 1 (Stock base; sling mount)

Parts prep: Clean out all 10-24 through holes with 3/16" drill.

Clean out 6-32 through hole in upper clevis side of the stock base with 9/64" drill - upper only (end with counterbore).

Tap drill lower clevis hole for 6-32 threads and tap it.

Mark length for cutting down 2" 6-32 SHCS as the sling mount pin. Once again, this is done to get a fastener with a long unthreaded shank. You can sub any equivalent fastener that has the proper unthreaded length. When installed, this becomes a Masada-style singlepoint sling attachment. Don't clip your sling onto threads!

Zip that to length and install it. Don't overtorque it, just snug it without distorting the clevis legs. PETG threads should self-lock sufficiently.

Tap these two holes for 10-24. As before, all 10-24 tapped holes print at tap-ready dimension, don't drill first.

Clean out these extrusions covering the stock tube hole with a knife, and deburr/deblip/sand the stock tube socket to slip onto 1" PVC pipe if required. Same for the stock base's socket.

Cut PVC to desired length. I use 4.5" as a starting point; this is a nice (CQB) length stock for nerf similar to a RS.

Using 2-part methacrylate adhesive, bond the stock tube into the stock body. Clean off all excess adhesive outside, then inside, before curing. Outside first, because the longer you wait, the more the MMA attacks the plastics, the more polymerized and gummier the resin gets, and the worse a mess you will have trying to clean it up. If you wipe it off quick, you will have a shiny clean exterior.

Do the same on the stock base - be prepared to set the orientation/alignment promptly, as the Devcon will establish a weld QUICKLY! Also, pay attention to the sling mount orientation per what side you want the sling point on/what handedness you printed your stock base as earlier! Do not put the base on upside down by accident here.

This is one of the few high-stakes, permanent operations in a '19 build assuming you use my stock setup. It works fine for me but I may be looking to add fastener holes as a more laid back option that is also able to be disassembled to change tube lengths or replace individual part failures in the future.

Anyway, you're done, stick the bolts in that for safekeeping and put it aside.

Next: Part 5 - Grip Assembly

No comments:

Post a Comment