SLAB - Silly's Lever Action Blaster (Nerf Homemade)

The SLAB: Silly's Lever Action Blaster. A Talon-fed half-dart lever-action springer.

Firing demo: 

General blaster overview video

Firing demo video

The SLAB is a lever action, Talon mag fed, half dart springer.

Sellers

A full list of US and non-US sellers can be found here.

Hardware kits

• SilverFoxIndustries
• OutOfDarts

Fully printed/assembled blasters

• SilverFoxIndustries
• SuperStressed3D
• OutOfDarts

Upgrade parts

• BansheeIndian
• PinkDragonTuning

Reviews

Videos:

• OutOfDarts: https://www.youtube.com/watch?v=-3QmJG-iSTI 
• Coop772: https://www.youtube.com/watch?v=0gnt4nkgSPQ 
• Lorddraconical: https://www.youtube.com/watch?v=IG3rWt_11c0 
• American Foam: https://www.youtube.com/watch?v=FAZ3mT-elwk 
• Captain Xavier: https://www.youtube.com/watch?v=ifkdSixZSd4 
• WalcomS7: https://www.youtube.com/watch?v=ACKjuRBVfR4 
• Boomstick Mods: https://www.youtube.com/watch?v=W_mRjcNI2pQ 

Performance

I usually recommend 12 inch barrel + MegaXL Spigot SCAR with SF25-TC or 5.5" k25 for maximum reasonable performance on the SLAB. It should hit ~220 fps.

Keep in mind that SCARs usually reduce performance a bit. If you plan to use a SCAR, make sure your barrel is long enough to come out the end of the muzzle for attaching the SCAR. Also keep in mind that a SCAR acts as a barrel lengthener to some extent.

The SCAR shown commonly on the SLAB is my MegaXL Spigot SCAR: https://www.printables.com/model/873465-spigot-scar-silly-scar-half-dart-and-megaxl 

If you are looking to have a specific FPS for your build, buy the appropriate hardware kit from your seller of choice. They will have specs and FPS estimates for the springs/barrels they sell.

Darts & Mags

The SLAB is compatible with pretty much any half length dart. Most people either use darts from Worker, or darts from Dart Zone. The SLAB uses uses Worker Talon magazines (and other magazines compatible with Talon magwells, such as OOD Koda mags).

 Worker Darts: https://outofdarts.com/products/worker-short-darts-200-pack-gen3-improved-darts-2021 

Dart Zone Darts:  https://dartzoneblasters.com/product/ruby-dart-half-length/ (Dart Zone also sells half length darts at Target and WalMart.)

SLAB uses Talon magazines from Worker: https://outofdarts.com/products/worker-15-round-straight-talon-short-dart-magazine-clip-6-colors 

(There are printed Talon magazine replacements on the internet that you could use instead as well.)

Hardware Info

Full hardware list/BOM

Note: Buying hardware from a licensed shop is cheaper than sourcing it yourself 99.9% of the time.

• Adhesive (two-part epoxy, plumber's goop, super glue, E6000) is used to keep the plunger tube attached to the TurnaroundCap. MAKE SURE TO FOLLOW THE ASSEMBLY STEPS CORRECTLY WHEN ASSEMBLING THE PLUNGER AND TURNAROUND.
• Using an elastic hair tie instead of elastic cord for the catch is recommended for aesthetics, but not needed. 
• The blaster is designed to use 4 inches of k25 spring with a 12 inch barrel. The barrel can be longer or shorter, and you can fit springs anywhere from 4 inches to 6 inches in the blaster. 
• The blaster also fits Longshot springs, but be careful with using super strong springs. The blaster is meant to use 788 and k25. It can fit k26 and k14, but those heavy springs WILL cause damage, and WILL NOT improve performance a worthwhile amount. 

Barrel Length

12 inch barrels stick out past the muzzle 80mm.

14 inch barrels stick out 130mm.

To use the MegaXL Spigot SCAR (LINK HERE), 40mm of barrel is needed past the muzzle (when in the firing position) to attach. With the short nut, 35 is needed.

The standard 10 inch SLAB barrel sticks out of the muzzle 28mm, so it can not use the Spigot SCAR.

Print Info

All STLs were exported in print orientation. F3D & STEP source files are also provided.

Filament usage: 

The minimum build volume for the SLAB is 150x150x150mm with alternate Lever parts. 170x170x150mm with all the standard parts. Remember to rotate parts to make them fit on your bed optimally.

This blaster is designed for PLA parts. Printing in other filaments (like PETG) should be fine, but might lead to broken parts.

Make sure the Z-Seam is set to have all the seams in one line for easy cleanup, or hide the seam some place where it doesn't matter or rub against parts. On the MuzzleB, excessive Z-Seam can rub against the plunger tube during the prime, making the prime feel awful. If your blaster is doing this, just sand down the Z-Seam(s). 

The GripPanel L/R parts need supports. CatchPusher *might* need supports, but it really depends on your printer's overhang performance.

The RailA/B, Ram, RodCap, RodCapPivot, RodCapKeeper, and PrintedCotterPin parts require brims.

Infills

• Black
  • PlungerRod 100% Gyroid, 5+ walls.
  • Everything else, 20% Gyroid, 5 walls. 
  • GripPanels need support.

• White
  • All at 20% Gyroid, 5 walls. 
  • Rails A/B need a brim and MUST be printed on the flat end.

• Orange
  • Muzzle attachments (Bottlenose, end caps, etc), Ram, RodCap, RodCapPivot, RodCapKeeper, PrintedCotterPin (x2), PlungerHead, Catch, and CatchPusher 100% 5 walls. 
  • Everything else, 20% Gyroid, 5 walls. 
  • The Ram, RodCap, RodCapPivot, RodCapKeeper, and PrintedCotterPin (x2) parts require brims.
  • The optional Bottlenose parts need supports.

• Green
  • StockPanels and StockCores at 10% gyroid, 4 walls. 
  • PrimeTransferBar (x2), 100% Gyroid, 5 walls.
  • Everything else, 20% Gyroid, 5 walls. 
  • The SideCovers L/R with text should be printed with THE TEXT NOT TOUCHING THE BUILD PLATE, using supports. The ones WITHOUT TEXT can be printed with the FLAT SIDE ON THE BUILD PLATE. This is done to keep the text nice and crisp. Maybe do a filament change on the layer before the letters to make them really pop!

Assembly

Assembly video by OutOfDarts (Clearer and quicker than the one I made): 

My old assembly guide: https://www.youtube.com/watch?v=RuWvdPNgs6U (watch at 1.25x speed, I ramble a bit)

Plunger Tube Glue Guide: https://www.youtube.com/watch?v=0BNuwjhlNqI 

•  Super glue or epoxy (or plumbers Goop, or hot glue or silicone or some other adhesive) is used to keep the plunger tube attached to the TurnaroundCap. MAKE SURE TO FOLLOW THE ASSEMBLY STEPS CORRECTLY WHEN ASSEMBLING THE PLUNGER AND TURNAROUND.
• Put the -123 o-ring, the two 016 o-rings, and the nut/thumb screw into the turnaround BEFORE attaching the plunger tube.
• When using the split turnaround, put an 016 o-ring between the two parts, screw them together, then glue on the plunger tube.
• Using an elastic hair tie instead of elastic cord for the catch is recommended for aesthetics, and it makes assembly easier. The HW kits do not include these. 
• The blaster is designed for 4 inches of k25 with a 12 inch barrel. The barrel can be longer or shorter, and you can fit springs anywhere from 4 inches to 6 inches in the blaster. The blaster also fits Longshot springs, but be careful with using super strong springs. The blaster is meant to use 788 and k25. It can fit k26 and k14, but those springs WILL cause durability issues for minimal meaningful performance gains.
• Use the PrintedCotterPins to keep the two long takedown pins in place (the ones through the turnaround and the lever).
• There are two very small pins. The slightly longer one is for the mag release, the slightly shorter one is for the trigger.

Community Upgrades / Variant Parts

This section is reserved for when people make their own parts for the SLAB.

These parts may not be updated to the current SLAB version. If you have issues, message the creator of the part.

• Chopped Magwell with a spring instead of elastic: https://www.printables.com/model/323885-slab-magwell-with-compression-spring 
• Barrel shroud/cover: https://www.printables.com/model/308896-slab-shroud 
• Marksman Kit (longer top rail, cheek riser stock, new muzzle attachment): https://www.printables.com/model/312661-slab-marksman-package 
• Mares Leg Kit (Short chopped stock, swoopy giant lever): https://www.printables.com/model/321813-slab-mares-leg-kit 
• Flat Face "modern" Trigger: https://www.printables.com/model/297608-slab-flat-trigger 
• TPU Priming Lever Sleeve: https://www.printables.com/model/392377-slab-tpu-grip-sleeve 
• SLAB Skeletonized Stock: https://www.printables.com/model/386480-slab-skeleton-stock 
• SLAB X Slingfire Muzzle: https://www.thingiverse.com/thing:5754622 
• Flat SLAB Buttplate: https://www.thingiverse.com/thing:5752277 
• SLAB N-Strike Barrel Lug: https://www.printables.com/model/316254-slab-n-strike-barrel-lug 
• SLAB N-Strike Stock Attachment Point: https://www.printables.com/model/338615-n-strike-stock-attachment-for-slab 
• Tenderizer Muzzle Plate: https://www.printables.com/model/338618-tenderizer-front-plate-for-slab 
• Paracord SLAB Handguard: https://www.printables.com/model/338606-paracord-slab-grip 
• SLAB Windowed Magwell: https://www.printables.com/model/338855-windowed-magwells-slab 
• Double Plunger Tube Abomination: https://www.thingiverse.com/thing:5663902 https://www.reddit.com/r/Nerf/comments/z6z8ic/double_plunger_slab_files/ 
• Muzzle spacer for extremely short barrels on the SLAB: https://www.thingiverse.com/thing:5852265 
• Rail B extension: https://www.thingiverse.com/thing:5901435 
• Single dart loading mag block: https://www.printables.com/model/390947-nerf-talon-single-load-block-for-sillybutts-slab 
• Stock and side panel picatinny, EXTRA TACTICOOL: https://www.printables.com/model/380984-slab-picatinny-rails 
• Imperial spec bar cutting jig: https://www.printables.com/model/342896-slab-caliburn-talonclaw-4-hole-template-imperial 
• Mega XL dart holder (picatinny mounted) (for MXL Spigot SCAR): https://www.printables.com/model/292339-mega-vertebre-rail-mounted-megaxl-dart-holder
• SLAB MLOK handguard (tacticool): https://www.printables.com/model/417044-slab-mlok-handguard-cut-at-an-angle

Troubleshooting

First off, thank you to my beta testers for helping me iron out the kinks in the SLAB before release. That said, there are still some common issues that people have.

Thankfully, they are solvable.

Blaster launches never go 100% smoothly, so please be understanding with any issues you have, as the design is still very fresh and hasn't gone through years of tweaking.

The following are common issues with the SLAB. If your issue isn't listed here, please message me (contact info at the bottom of this page).

• Catch issues and/or gummy gritty trigger:
  • This is usually caused by the catch being oversized or too tight. Take off the handguard (6 small screws), and take out the catch. The catch should slide 100% freely in the muzzle area, no noticable friction. DO NOT LUBRICATE IT, take out the catch and use sandpaper on the sides until it slides freely. The handguard does not need to be installed in order to test the blaster, only put on the handguard at the end of testing the fix. SilverFoxIndustries SLABs from before Spring 2023 are especially succeptible to this issue.
• Flubs/Squibs: Flubs/Squibs are seemingly caused by several random things on the SLAB. Common causes include: 
  • Barrel too long for given spring weight. Try using a shorter/longer barrel. As testing is done, I will update this part of the page with common spring/barrel combos for specific FPS numbers.
  • Darts getting bent as they are chambered. This can be solved by changing which ram you are using. The flat face ram chambers smoother, but doesn't push the dart into the barrel as far as the pointy ram.
  • Roughly cut barrel ends grabbing onto darts as they go through the barrel. Solved by sanding or chamfering the ends of your barrel to be smoother.
  • Missing or broken o-rings around the barrel in the turnaround. Replace these o-rings if they break. Barrel o-rings can be broken by sharp edges on the ends of your barrel. As you put in the rough barrel, it cuts up the o-rings.
  • Bad seal between the plunger and turnaround. This can be solved with adding more glue to the connection between the plunger tube and the Turnaround.
  • Bad ram seal. This can be solved by printing the T or Tighter ram variant, or switching to the Lynx hardware ram (which is adjustable to much tighter levels). LUBE YOUR RAM O-RINGS!!!
• Catch won't catch or release: tighten/loosen catch elastic, thread in/out trigger linkage rod to push down the catch less/more. If your rod is threaded out too far, your catch won't catch the plunger. There is also a spot on the top of the trigger to put a 4-40 screw to fine tune trigger pull distance if needed.
• Gritty/sluggish prime: Can be caused by several things.
  • On the MuzzleB, excessive Z-Seam can rub against the plunger tube during the prime, making the prime feel awful. If your blaster is doing this, just sand down the Z-Seam.
  • Your Turnaround might be rubbing against the aluminum bars because the prints are too tight. If this is happening, sand down the prints where they are excessively rubbing.
  • You might have not lubed things correctly. The plunger tube needs lube, and the o-ring(s) on the ram need lube. **DO NOT LUBE THE BARREL O-RINGS.**
• Wobbly top picatinny rail: If it is wobbly front to back, print the RailSpacer part and put it between the two top rail segments. If it is wobbly up and down, put some tape on the aluminum bar inside the rails to act as a shim.

Changelog (v4 SLAB (release)):

To see the full changelog and see the old versions of SLAB, go to the GitHub page https://github.com/Sillybutts/SLAB.

• Changelog: 8-25-2022: Blaster release.
• Changelog: 9-5-2022: Updated parts. 
• Changelog: 9-21-2022: Uploaded v4 assembly video.
• Changelog: 9-22-2022: Updated and added parts.
• Changelog: 9-23-2022: Updated parts.
• Changelog: 11-27-2022: Updated print guide.
• Changelog: 3-18-2023: Tons of small changes and improvements.
• Changelog: 2-29-2024: Added a new handguard.
• Changelog: 5-8-2024: Uploaded the current version of SLAB to Printables. 
• Changelog: 8-29-2024: Fixed an outdated file for TopCover. The correct one has been on GitHub for a long time, but I apparently uploaded an old version for Printables. That has been fixed. Now it has the proper holes for the optional top picatinny rail. Thanks to SilverNutter for bringing this to my attention! 

Misc.

If you build any of my designs, I'd love to see yours! Feel free to message me on Discord (Sillybutts#5905) or tag me on a post on Reddit (u/SillyTheGamer).

Thanks to OutOfDarts and SilverFoxIndustries for providing some photos.

Thanks to ThePixelatedCat for doing the blaster mechanical animation via commission.

China: 你好！ 我擁有這個設計。 想生產請聯繫我. 你好！ 我拥有这个设计。 如果你想生产，请联系我.

Disclaimer: This is not a toy. This blaster is meant for hobbyists, not children. Blaster must be operated correctly to avoid injury. I am not responsible for any injuries from this blaster. Please use a bright/blaze orange muzzle and barrel cap on this blaster. Consult local laws before building this high powered blaster.

Donations & Merch

If you like what I do, please consider supporting me! 

I don't charge for my files, so any donations or merch purchases would be greatly appreciated!

• Patreon (Monthly donations)
• Buy Me A Coffee (One-time donations)
• AWESOME shirts made in collab with Brandon Diaz
• RedBubble My merch shop, full of fun Nerf-y stickers and shirts!