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#353681 Constant Force spring blaster infodump

Posted by snakerbot on 22 May 2016 - 09:51 PM

IMG_3157.JPG

A while back I posted this in the homemades pictures thread.  In short, it was a blaster whose energy source was a constant force spring, like the kind used in Raider drums or your tape measure.  Specifically it was 9293K12.  For those who are not familiar, a constant force spring is a flat piece of metal wound in a coil around some sort of central shaft or bearing.  When you pull on the free end, the coil rotates around this shaft and unwinds.  Because pulling the free end farther only unwinds more of the spring, it doesn’t get any harder to pull as you pull it farther, hence the ‘constant force’ descriptor.

 

The origin of this experiment is several years ago when a poster on this forum (I can’t remember who it was or what the original context was) offhandedly mentioned constant force springs.  Fast forward several years and I have a job, disposable income, and boredom, and decide to give this a shot.  The original plan was to build a new blaster to run the experiment with, but I got lazy and retrofitted my extension spring rainbowpup instead.  Because of the nature of constant force springs they can really only be put into rainbowpup/eslt/whatever type blasters with plungers that are pulled instead of pushed. 

 

I’m going to drop some physics on you guys here.  I wasn’t sure exactly what spring to get, or how strong it should be.  Constant force springs really are a completely new area, so there are no “standard” springs or rules of thumb or anything.  Constant force springs don’t have a “spring constant” like compression or extension springs do.  So how to compare?  I didn’t come up with a good answer to this until much later.  What I eventually did was just guess and pick a spring whose draw force was about halfway (a little more actually) between the no-extension and full-extension force of the 9432k125 I found for my rainbowpup.  After buying the spring I realized that the best comparison was probably energy release.  The potential energy stored in a compression or extension spring is given by the equation E=0.5Kx^2 where E is the potential energy stored by the spring, K is the spring constant, and x is the displacement of the spring.  The potential energy stored in the K125 spring at the 6.5” of draw I use is therefore 65.4875lbf*in or 7.4J.  The potential energy at rest (I use no pre-extension) is 0J.  So the total energy released during firing (not all of which goes into the dart) is 7.4J-0J=7.4J.  So for the most equal comparison I should find a spring that can release 7.4J over 6.5in of travel.  Turns out by complete accident, I hit that on the nose with the spring I bought.

 

The potential energy of a constant force spring I couldn’t find online or in my machine design textbook, so I derived it.  (If someone finds a mistake in this result, please let me know, that might explain some things).  What I got was E=Fx where E is the energy released, F is the spring force, and x is the displacement.  So our total energy here is 68.9lbf*in or 7.78J. 

Note that the displacement term in the compression/extension spring is quadratic, while the displacement term for constant force springs is linear.  That means that for higher draws, the constant force spring falls behind in energy very quickly, but for this blaster/spring combo, I had almost exactly the same energy, so I moved forward with this.

spring energy graph.png

 

So theory over, let’s talk practical application.  The edge of the spring needs to line up with the plunger rod, because that’s where the free end comes off.  To accomplish this, I used a 1.5” pvc tee and carved it to the nines so I could mount the spring a little off to the side.  I drilled a hole through the tee and used sliding door bearings to hold the spring.  I ground them down so one edge of each could fit into the ID of the spring. 

IMG_3315.JPG

IMG_3309.JPG

 

For attaching the spring to the plunger rod, I used a section of ½” nylon rod (the same material used for the plunger rod).  One end was threaded to screw onto the end of a small stud with the priming disk on it.  The other end had a slot in it, into which I inserted the spring.  A small screw goes through a hole in the end of the spring (the spring comes like that) to affix the two together. 

IMG_3317.JPG

IMG_3311.JPG

 

Assembly is a bitch.  To get the spring into the tee, I had to hold it in place and slowly thread the bolt down through the tee, alternating between rotating the bolt a turn or two and then going back and rotating these nuts a turn or two.  Once that was done, I inserted the plunger extension into the front of the blaster body.

IMG_3322.JPG

That is where it sits at rest, so I had to stick my finger in the tee at the front and force it down towards the plunger rod. 

IMG_3323.JPG

Then I turned the plunger with my other hand to thread the two together. Not fun.

IMG_3327.JPG

 

So how does it shoot?  Not well.  I’m not sure of the exact reason now, but this blaster had trouble.  About one in five darts didn’t leave the barrel.  The ones that did didn’t seem to shoot as hard.  I don’t have a chronograph, but range tests show a clear drop off. I have a couple theories for why this could be.  First, while this spring is labelled as ‘constant force’, it isn’t like that, not quite.  Constant force springs take a small amount of travel before they reach their listed force.  I guess this is due to the shape of them or something.  I have a couple inches of pre-travel built into this setup, but maybe it isn’t enough.  Further, there is almost certainly more friction in this setup compared to an extension spring.  The bearings I used are a source of some of this, and the priming disk in the middle of the plunger rod is surely rubbing against the inside of the body because of the shape of the spring pushing it sideways.  There is also a possibility that the spring, which is 1in wide, is scraping on the inside of the front body of the blaster.  One final reason is that the process of disassembling this blaster and replacing the spring seems to have messed up the rod seal a little bit.  I’m not sure why, and it doesn't seem bad enough to account for all the problems I see.

 

I said in the pictures thread that “this is the weirdest thing ever”. What did I mean by that?  Well, it primes like nothing else I’ve ever used.  I’m not even sure how to describe it.  “Light” is almost right, but that isn’t really it.  I end up smashing the priming handle hard against its stops almost every time I prime it.  It’s like I begin to prime back and am expecting a certain amount of force based on how much resistance at has at the beginning, but then it throws me for a loop because that extra resistance doesn’t come.  I’m sure I could get used to it eventually, but it is pretty weird at first.

 

So, difficult to assemble, expensive ($10.83 for one spring!), weird to prime, and not shooting quite like you’d expect.  Are there any upsides?  I don’t know.  If you could find the right spring, and get the geometry correct (no grinding), you could make one of these that shot pretty well and maybe felt like it had a weaker prime, but I don’t consider that worth it.  Extension springs already have pretty light primes for how well they shoot, and I don’t see this offering enough advantages to overcome the disadvantages.  I’ll leave the blaster as-is for a little while if anyone wants more pictures or wants me to do any more tests, but I don’t see a good reason to keep it as it is forever.

 

Crossposting additional pictures from the homemades pictures thread here, so it's all in one place.

IMG_3159.JPG

Not primed:

IMG_3160.JPG

Primed:

IMG_3161.JPG


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#358196 1995 Crossbow CAD Files

Posted by CaptainSlug on 24 February 2017 - 05:10 PM

I haven't modeled the springs yet. I'll add them to the set soonish, then make the STL files available.

 

STEP 214 Format: http://captainslug.c.../Crossbow95.zip (2.6mb)

 

Stitched Shell Scan: http://captainslug.c...erf/cb95_s1.jpg

Exterior DXF: http://captainslug.c.../Crossbow95.dxf

Cutaway DXF: http://captainslug.c...bow95inside.dxf

c95_11.jpg

c95_12.jpg

The internal parts are 100% measurement accurate. The shell however isn't exactly dimensionally perfect. It's been altered for improved strength and more compatibility with 3D printing (hopefully).


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#354914 FDL-1: Fully 3D Printed Robotic Blaster

Posted by jkovarovics on 10 July 2016 - 09:39 AM

Hey everyone,

 

I wanted to introduce you guys to the FDL-1. Some of you may have seen a prototype version in a Drac video a few months back and anyone who was at DartCon during NvZ this year probably saw it in person. It's a fully 3D printed Mega blaster controlled via an Arduino like microcontroller running brushless motors. I've also open sourced it so people can print their own if they're up to the challenge. I have a website setup with a webshop. It's http://www.fdl1.com. If this perks your interest, check it out, there are more pics and info there. There are also links to the Thingiverse page and Facebook page.

 

Just to be clear, I am not here to market the FDL-1. If you want to buy something, cool, but I mostly want to show this to Nerfhaven. I entered the Nerf community from the maker world. I had no idea the stuff you guys were making. My first war was a Nerf culture shock. There was 3D printing all over the place, blasters mashed together, painted, hydro dipped, the works. I was impressed to say the least. The point being, I had never had anyone tell me you couldn't or shouldn't print an entire blaster or use brushless motors or make the thing robotic so I just did it. I spent over a year revising the entire design over and over based on my experiences of using it in the office then on the field. In the maker world, bigger is almost always better so I went with Megas. I also hadn't seen a flywheel mega blaster released by Nerf at the time so I took that on as a challenge. Anyway, I posted about this on reddit a few months back and got slammed with criticism. I just came on here looking for a NIC blaster design for NomNE and saw someone talking about 3D printing a full blaster. Some of the first comments were you shouldn't and that you can't print flywheels. It pains me every time I see those responses. In the maker world we ask ourselves what if? I feel like the NIC does a lot of asking why. I never asked myself why would I print an entire blaster, I just asked myself what if I did and did it. What if I took the motors off my drone and stuck them on there? What if I want to operate the thing remotely? Use a microcontroller. What if a revolver is clunky? Load it from the back with a button to advance it and throw in an IR sensor so it doesn't dry fire empty chambers. All what ifs. The NIC is full of brilliant minds and makers at heart. I'd hate to see a cool design not created or a mod not done because someone asked you why you would do it or told you it was impossible. Just try it.

 

Anyway, here's a pic. Let me know what you guys think. My next design will be mag fed before that comes up. Nerf, make, print on

 

aPLCSN4.jpg


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#354210 Armageddon XVII: SoCal's Largest NIC War (2016)

Posted by Ryan201821 on 14 June 2016 - 10:34 PM

Great war. It's been 7 years since I've been to a 'Geddon. It was cool seeing a bunch of people I haven't seen in years, and also meeting a bunch of new people I've never met. The war location is excellent for a war this size. I especially admire the perfect symmetry allowing different games to be set up easily and accurately with little effort. Thanks to Zeke for putting up with everyone's bullshit for the weekend, and the time and cost that goes into hosting a nerf war, especially one this size. 

 

Things I liked:

  • Death clicker gametype is a perfect mashup of Deathmatch and Meat-Grinder. I need to get some mechanical counters.
  • U3 trains
  • Other general trains that were rollin'
  • Rock Mode, of couse.
  • I took a nice cold one.
  • Double ESLT is super effective, still...The blowgun is the perfect attachment for shooting little kids, or rushing fools while making poop sounds.
  • Little kids who were smarter than a lot of the older people.
  • Lots of ideas for potential future projects to revolutionize nerf once again.
  • Weather 

Things that could've been better:

  • Staging area was too close to field of play. Maybe we should just tell people expect to be shot at all times, within the gated area. (i.e. wear safety glasses)
  • Decent cover, but a couple smaller mobstacles in the more open areas would've made it perfect.
  • Not having to fly on a plane to get there.

Things that need to change:

 

  • FVJ darts, and other not-even-close-to-soft domes = not nerf. These things are straight rocks, yo. I saw some pretty nasty damage to some people from these darts and at points it was generally frightening to walk into certain situations. I think this was also amplified by the most likely over-powered blasters they were using. 
  • Loudspeaker would be a nice addition. Sometimes it was difficult to wrangle people to the next game. Especially since none of us were very good at yelling.
  • Darts in general. Maybe by this time next year we'll finally have the end-all solution.

 

I definitely plan on going next year. Sorry East Coast, but it is better than Apoc.


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#357858 Good wills and Thrift stores in New York City

Posted by ToadBrews on 06 February 2017 - 02:56 PM

You have a massive sense of entitlement and you expect everyone else to do your research for you. Neither of those will help you get ahead in this hobby, or in life. It's hilarious you're upset a random goodwill employee didn't know how much a legendfire costs when you, someone who has an interest in foam blasters, also had no idea. No one forced you to make a bad purchase. Nobody ripped you off. You picked up an item with a price tag on it, the cashier charged you the amount on the price tag, and you took the item home. Then when they gave you a store credit to make up the difference (something which was a courtesy to you and theynhave no legal or ethical obligation to do) you went on the internet and racially profiled them and called the manager a bitch. The problem here is you.


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#357155 Homemades Picture Thread

Posted by EocDragon on 14 December 2016 - 08:02 PM

These are basically homemades:

O1UtME8.jpg

 

So I've been collecting Berserkers for a while because they have that sweet, sweet 4B tank inside. Berserker shells are hot garbage though, so I never did anything with the dozen or so that I have, since I don't want to just chop the front off of the shell and call it a day and I also don't want to spend 6 hours dremeling the fuck out of some other, better shell for each one and every one.

 

I do have a 3D printer though, so rather than remake all of the files for my springer homemades that I lost when my hard drive crashed last year, I procrastinated and made these instead. They're essentially 3D printed shells specifically for the 2nd Gen Berserker tanks so that I can print them over them the course of a day and then drop the tank in with minimal effort. Everything is mechanically fastened so the whole thing comes apart to maintain the tank or replace broken parts if that happens. 

 

Ranges are unplugged 2nd Gen 4B ranges. I might eventually make a version for the 1st Gen tanks, but those Berserkers are less common (fun fact, did you know that there are 5 variants with the 2nd Gen tank to the one original variant with the 1st Gen?). For now they're pretty easy to make loaners for wars (it's harder for the kids to break unplugged air blasters).


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#356160 JSPB3D

Posted by 3DBBQ on 08 October 2016 - 04:07 AM

jspb-3d-astm-free_orig.jpg

Introduce:

Hi! This is my new work, part of the use of 3D printing, it is very simple production,
just need to put it together , glue together, and you can change the style you want.
 
This model looks like some of the features of the past works, is not the same place? 
it has reserved some air road,using PU soft tube to connection, in addition to the RSCB Clip can be added,
the future can also connect another pump to push the clip inside darts.
 
The second pump push the darts inside the clip videos:
JSPB Pro2 does not need to muzzle down to load, JSPB Pro2 can continue shooting.
 
 
Pump air in to the Clip inside the darts to precision position is not easy, 
they must create an air escape,to prevent the continuous emission of darts.
 

3DSTL Files : 

https://drive.google...N00?usp=sharing

JSPB3D SCH40 core.STL
JSPB3D SCH40 breech ring.STL

JSPB3D trigger.STL

JSPB3D guard.STL
Breech block.STL
lock plate.STL

 
 
3D Printr settings:
I used the layer of 0.25mm and 0.6mm of the nozzle,
Basically, this model is fairly easy to print and does not require supporting materials.
 
Specification:
In Asia to get CPVC SCH40 is difficult, here are the use of CNS specifications,
Later I ordered the HERSHY CPVC4120 SCH40 on the Internet ,so I actually tested it
 
Tolerance issues:
Too tight part can use the hammer to knock into, too loose place can increase the thickness with PTFE TAPE,
Model tube through the place where most of the design groove, you can also plug O-Ring,
There is another way is to use screws to fix.
 

 

Part list:

j3d-white-up_2_orig.jpg

ABS rod  Φ5mm
SCH40 1/2"
SCH40 3/4"
PETG 1/2"
CHECK VALVE 1/2"  x2
PU-Tube 8X12mm 
OS   3/4"
1/2" Elbow   x2
3/4" Cap 
Pump
7X1.9  O-Ring
16X1.9  O-Ring
24X16X2 Rubber washer
Screws 5/32 X 1/4
Screws 5/32 X 5/8
AB Glue

Option:
1/2"  Tee 
1/2" Cap
Cable tie 
PTFE tape
Air flow direction:

 

j3d-white-up-air_orig.jpg

using screwdriver and a hammer to chisel a path to add more airway:

 

 

airpath_1_orig.jpg

 

img-1675.jpg?306


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#355527 Modification and Paintjob Pictures

Posted by Ryan201821 on 13 August 2016 - 11:24 PM

P10206811-1.jpg


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#354691 Plusbow Rev. 3

Posted by CaptainSlug on 30 June 2016 - 08:48 AM

bow3_007.jpg

 

Plusbow Rev.3 Guide

 

Instructables Mirror

 

Design Goals

  • Reduce Part count
  • Two Options for Plunger tubes and Plungers (+bow or 2-11)
  • Omni-directional catch
  • Spring guide to remove "serpentine" behavior
  • Ease of dis-assembly
  • Limit screws to two lengths (1/2" and 1-1/2")
  • "Check Valve" Plunger head
  • Use of extension springs or rubber bands for catch (multiple configurations possible)
  • "Ultra-Compressible" O-Rings
  • NO MORE INTERNAL CUTS, that means no pilot holes, no feeding a scroll saw blade through a pilot hole. Every cut can be done with a scroll saw or a band saw.

Total Build cost: $70 (for one plunger tube type)

Sunk Cost per Plusbow: $25

 

 

Thanks to: Splitlip, Aeromech, Ryan McNumbers, Groove, CrankyMonkey, VACC, and TED


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#354638 Looking back at 14 years in the LGLF...

Posted by Langley on 28 June 2016 - 02:25 PM

14 years ago today, I met up with my friend Fred from highschool and we modified a nerf blaster, committed an act of petty larceny, and signed up for a Geocities account.  The blaster was actually a Super Soaker XP 150 modified to shoot nerf darts, the theft was a garden gnome from the garage-sale addicted hoarder down the street, and the Geocities account was for the LGLF homepage.  5 weeks later we joined up with one of my nephews (Left Nut) and found ourselves at the first annual Apocalypse nerf war, where we met Vacc and Spoon (the original founders of NerfHaven), One Man Clan, and the members of the Lawn Chair Mafia nerf clan.  A couple of weeks after that we hosted our own war, and called it GnomeFEST.  We were the baddest group of toy-gun-toting dorks in New Jersey.
 
Langly.JPG
 
Over the next few years I met Talio and we all went on a road trip down to the D.C. area to nerf with Crankymonky and Groove (Edit: yes, and THIRST.).  Shortly after that, Hasbro sent a designer and an engineer out to a GnomeFEST to meet us, and they recruited Talio and One Man Clan into an early version of their Nerf Ambassador program.  The designer from Hasbro is still working there, leading the team on the Rebelle line.  We nerfed around Philadelphia and some paintball field in bumfuck Delaware, and had a few more Apocs and GnomeFESTS.  Around 2005 One Man Clan agreed to pick up some kid from Hoboken who he'd never met on the way to a war.  They sat in uncomfortable silence for about an hour as OMC wondered how this guy was going to load a nerf gun with only one arm.  That guy was JLego, and he turned out to be the fastest most impossible to hit nerfer at that event.  We met lots of other people over the years, and some drifted away or stopped nerfing, including Fred, and then eventually, me. 
 
When I came back in early 2008 after a two year hiatus, I reconnected with Talio and JLego, and they introduced me to some new guy named Splitlip.  We all agreed to carpool down to a DCNO later that spring, and in an alcohol fueled surge of collective nostalgia, the four of us decided to re-boot the LGLF. A month later Talio joined the Mag7 in the worst act of betrayal on American soil since Benedict Arnold.  But that was okay, because we would add Muttonchops in 2009 and Gears in 2010.  Our old allies Crankymonky and Groove would both join us in 2011, and (though he'll deny it) TED joined in around 2012.
 
Over the years we traveled all over the east coast, to Maryland and Virginia, Philadelphia, Pittsburgh, Toronto and Chicago.  We went to Penn State for Humans vs Zombies, and some of us flew out for Armageddon in Los Angeles.  We made a lot of friends on those trips, and even more came out to visit us every year at Apoc.  We met the Sex Dwarves of Pittsburgh, and the U3 and Rainbow Clans from Chicago.  We played with nerfers from Ohio, Minnesota, Oregon, Washington, Georgia and Florida.  We helped host Geddon, DCNOs, ECNOs and NENOs.  We ate Hasbro's Pizza and we drank their beer.  We busted UIN13s balls, hit on Lord Draconical's girlfriend and pooped in Forsaken Angel's toilet.
 
I got a little carried away there.  What was I saying? Oh yeah. 
 
I love this clan, and the people who are in it.  It's been an incredible 14 year journey and I wouldn't trade it for anything.  I know we're scattered all over the country now, and I'm well past my nerf expiration date, but I'll keep going if you do.  Thanks guys. 
 
-Langley
 
GroupShot.jpg
10371602_10103866900172939_971413470646675538_n.jpg
10356689_10104346792654559_548979891915000760_n.jpg
1420585665-316199-5-lglf.jpg
GLHF.jpg
 
There are some more photos I dug up in this album on facebook: https://www.facebook...59315644&type=3
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#354211 Armageddon XVII: SoCal's Largest NIC War (2016)

Posted by Langley on 14 June 2016 - 10:46 PM

  • Loudspeaker would be a nice addition. Sometimes it was difficult to wrangle people to the next game. Especially since none of us were very good at yelling.

 

I appreciate the euphemism, but 'loud asshole' is the proper nomenclature.  I'll try and make it next year. 


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#352868 Stryfe Mag Release Extender

Posted by Cappucino on 19 April 2016 - 05:08 PM

Hi Folks! Today I wanted to get an extended mag release button for my stryfe, but I didn't want to pay a lot for shipping from Hobby Mods. So I made a nice little homemade one! I'm pretty sure someone has done this, but I wanted this to be here for reference. So I present to you, my homemade Stryfe extended mag release button. (I'm not sure if you can do this with other stryfe style mag release blasters, but I'll check on that.)

 

So this is what mag release looks like.

 

IMG_5717.JPG

 

So Start out with your Stock mag release stryfe

IMG_5718.JPG

 

Open up your stryfe. (This stryfe is my old modded one)

IMG_5719.JPG

 

We will be focusing on this area right here. This is the mag release.

IMG_5720.JPG

 

Take out that screw and take these two pieces out.

IMG_5721.JPG

 

We do not need this piece. You can put this in your extra parts bin.

IMG_5722.JPG

 

Now take this Mechanical Dart Lock out.

IMG_5723.JPG

 

This is what it looks like.

IMG_5726.JPG

 

Remove the spring on it. And Trash or keep it. 

IMG_5728.JPG

 

Now you are left with this.

IMG_5730.JPG

 

Cut this small nub off with a dremel and some other cutting tool. 

IMG_5732.JPG

 

Now grab the other piece of the mag release we had before.

IMG_5734.JPG

 

Add your choice of adhesive to the green spot. (I used hot glue, but you can use something stronger)

IMG_5737.JPG

 

This is what it should look like after

IMG_5741.JPG

 

Now place it back into the stryfe

IMG_5742.JPG

 

Put the screw back on

IMG_5743.JPG

 

Finally, put the other half of the shell back on and screw the stryfe back together.

IMG_5744.JPG

 

 

 

And there we have it, the homemade, cheap extended mag release! This is my first writeup, so I would like any kind of feedback. Thank You!

Attached Thumbnails

  • IMG_5737.JPG
  • IMG_5741.JPG

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#358714 THIS one simple design will have you in TEARS...

Posted by Chanclas on 22 March 2017 - 11:54 PM

Hello, everyone! I have been dead for a long time on here. I'm back for today because I couldn't keep this a secret any longer. THIS PROJECT IS ALMOST COMPLETE, this is not a full write-up. It loads and fires but has a bad seal. I can fix that but I don't have time--I haven't touched the project or even the tools in many months. That's why I'm just gonna show you my thing and let you do what you want with it.

 

No official name but let's call it the Sex Pistol for now. First person to perfect it gets to rename it. But do you really want to?

gun one.jpg gun two.jpg

 

The biggest inspiration was the Multiple Orgasm, by makeitgo. The day I saw that thread was the day I finally had what I needed to make the SP. Let me tell you, I had some far out ideas about how to make a mag-fed pistol, none of them realistic.

 

The Sex Pistol is just a like a real pistol. You can load a magazine in the handle, cock the slide back, slide returns forward, you pull the trigger, dart leaves the barrel. It's got some weight to it, feels good in the hand, and is 12" long.

ANIMATION of sexy 1st design

 

Of course, nothing stays the same. I've changed some moving parts when I found out that the real world isn't the same as the 3D model world.

VIDEO of sexy man cocking and dry-firing the Sex Pistol

 

The best change I made was the way I made the handle and the magazines. For the handle, I used a heat gun to soften the 1-1/4" PVC and then shoved two lengths of 1/2" PVC inside, side by side, to "spread" it from the inside. While it cooled, I pressed it between two wooden boards to flatten the sides a bit. The result is so comfy and strong. For the magazines, you can do the same with 1" thin-wall PVC, with two lengths of 1/2" CPVC inside--OR you can shove the softened 1" pipe inside the handle you already made. As it cools, wiggle it around and slide it in and out--this will keep it from hardening and getting stuck. You can cool the pipe faster by spraying water on it. ALL OF THIS SHOULD BE DONE IN A VENTILATED AREA--some, like Captain Slug, would suggest that you also wear some kind of respiratory protection.

 

The coolest change is the way the slide can be locked in the cocked position to allow for easy magazine swap. This came about from a design change where the magazine would be "closed" at the top which wouldn't allow the dart-retainer-lips-things to spread around the bolt. I like this feature, even if the magazine lips are open and allow the bolt to pass through. You wouldn't need this slide-lock if you decide not to add the slide return spring, which is on the barrel and pushes the slide forward after being cocked. But why wouldn't you want that?! It's so cool!

VIDEO of sexy man poppin' and lockin'

 

The most difficult change was the damn "mobile" catch and trigger assembly. The first reason for this change was that the plunger and catch would slide back in the plunger tube, instead of firing, when the trigger was pulled. Only way to stop that was to hold the slide forward with your free hand, which is dumb. The solution was to come up with a trigger that pushed up or forward or both. I went with the one in the middle on the left side of the animated image linked below. The trigger is a length of 1/2" CPVC, with a hole cut out to allow for the gray flexible trigger-catch-pusher-thing. The gray strip is just thin metal with a rounded nub of plastic glued on it.

ANIMATION of trigger designs

 

The second reason was that the simple 3-layer catch shown in the animation was not easily fabricated with my sexy Dremel and wasn't strong enough. The result is a big ugly thing but I believe it is an original concept. Imagine the plunger entering from the right, catching on the ring in the middle. The trigger pushes up on the ring, which is bonded to, and flexes up on, a strip of CPVC extending from the CPVC section that is the left end of the catch.

20151207_175054_HDR.jpg

 

There are a few things I designed that I'm pretty sure are new ideas. Dammit, I give up, I'll just have to get better pictures tomorrow. I haven't updated the model so you won't like it if you see it. Even if I wanted to, my computer is too old to be sexy and can't even install AutoCAD properly.

 

A few little notes:

-Magazines can be made any length but mine is currently long enough for 14 darts

-Magazines can fit darts up to 1-1/4" in length

-Ranges aren't expected to be impressive, even with a perfect seal. Current stroke is 2-3/4", I believe, which is pathetic, I know. That's just how it is, unless you make the pistol longer.

-I know it's big but it's also smaller than you think.

-Here's a Google Drive folder with all the pictures and videos and maybe the .dwg model file thing.

-Another fitting name for this pistol is Pillow Talk. I was gonna say something gross that rhymes with "eremature pjaculation" but I didn't. Also, it's full unofficial name is Sex Pistol: Experimental Reloading Mechanism.

 

One more thing. When I was about halfway done building the first crappy prototype that barely held together for a few days, I emailed the guys that print and sell ESLTs and PullSCRTs. They said they'd print any design if you were willing to pay for it. The price they gave me wasn't sexy and they said my model wasn't printable. That's fine, no hard feelings. I had laughs and tears working on this. Thank you guys for not stealing my concept and making it better and printable.

 

Okay, I'm spent.


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#358186 Koosh Vortex Tornado Scans (Now a shell replica concept thread)

Posted by CaptainSlug on 24 February 2017 - 12:21 PM

This is still a work in progress. This isn't a laser-scan and I only just started the internal features, but I do have the exterior as done as it can be without having access to more expensive equipment.

The goofy process used is to scan the inside of the shell using a flatbed scanner.

c95_10.jpg

This is two and a half scans stitched together with the ruler in each of the scans to confirm scaling and orientation. The scanner does add some optical distortion so that overall dimensions have to be checked against the shell.

 

The scan can then be loaded into drawing mode in Solid CAD software and traced. Those flat traces can be used to extrude out a solid model version of the shell. Alternatively the features that you want to copy could be filled in black and saved as a 2-color image and software such as Inkscape could convert that image into a DXF file, though that process can be kind of annoying and the DXF it makes can sometimes be kind of messy.

 

Anyway, I copied the outlines of all the features into a part and modeled all the exterior features. And after 3 hours of doing that I have this.

c95_09.jpg

So this is only likely to be a 93% accurate reproduction of the original shell and there are some features I'm going to drop (such as the bow arm attachment feature which nobody will use). A more accurate model would require an alternate method such as a CMM. We have one at work now but I'm still being trained how to use it. This model also doesn't require extreme precision since I can use the 100% accurate models I made of the rest of the parts to error correct all the internal features while modeling them.

 

The next step is to copy all of the internal features such as cross-members, posts, part cutouts, and then the inside contour of the shell. These all have to be modeled as separate parts to keep the file sizes down. They can later be merged together with boolean operations either in the CAD software or externally as STL files using Blender.


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#355367 Apocalypse 2016 - August 6th in Ocean Township, NJ

Posted by TED on 05 August 2016 - 12:25 PM

If there isn't a 3 team deathwatch using  Pokemon Go teams I'm not going.


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#355175 Sear Carbine Writeup

Posted by Aeromech on 24 July 2016 - 10:34 AM

The idea of using some type of sear to lock a bolt in place has been used on real-steel firearms since the advent of the machine gun, due to the simplicity and self-locking action of the mechanism. In the homemade Nerf market, this is a relatively new field, first being implemented on the ESLT some years ago. This is my attempt to marry SNAP style redneck engineering with the aforementioned locking mechanism.

 

RULES:

-No McMaster/Online ordered parts (Barring a [k25] spring, Good luck finding 11" long springs at a hardware store).

-No special tools required (No long-shank countersinks, holesaws, or any of that)

-No 3D printing

-Keep weight as low as possible

 

TOOLS:

-Rat-tail file

-Pocket knife

-Electric Drill with standard bits (no larger that 1/2")

-Woodsaw

-Hacksaw

-Screwdriver

-Sandpaper

SUPER HELPFUL BUT NOT NECESSARY

-Belt sander

-Drill press

-Table saw

-Vice

 

For this Writeup, descriptions will be BELOW the photos they reference.

 

4_zpsyhqpbuso.jpg

This was the original idea, using 3D printed components. I wanted to do the same thing without limiting myself to 3DP parts. But this is the idea. Borrow an ESLT/submachinegun catch and use it in place of the fickle SNAP nail and clothespin catch. Insert anecdote of "my SNAP shoots like 150 feet and I've never ever lubed it or replaced anything on it ever" but I have built three and they have ALL failed within 100 shots. Stop trying to convince me. Unless there is some kind of drastic improvement in the design I will not endorse SNAPs as being consistently war worthy. Moving on...

 

The actual catch mech can be seen here. a slot through the body tube and bolt allows a catch finger from the sear to rotate upward and extend into the bolt slot, blocking the bolt from moving forward, when the trigger is pulled, it pivots the sear downwards and the catch finger moves out of the bolt slot, and the bolt flies forward under spring force.

 

20160723_223928_zpswe3vfru2.jpg

This is the bolt. It is made of 1" PVC, with both ends capped off by cutting board. Get the fat kind, from Walmart, It's $6 and is like 1/2" thick, really great stuff. This bolt is about 7 inches long.

 

20160723_223932_zpslx5wydar.jpg

Superlative plunger head screwed into the front. Actually provides a really good seal on this thing.

 

20160723_223940_zps3vpeydo1.jpg

The back shows a 1/2" dowel sunk into the tube, with the rear cap held on by a screw into the dowel itself. I cut the bolt too short so the cutting board is sticking out, but yours shouldn't stick out.

 

20160723_223953_zpsdyqzztgb.jpg

Pretty standard at this point. Gooped in front bushing, with a slot cut 6.5 inches away from the front, running all the way to the back.

 

20160723_224142_zpsd8tiwehq.jpg

This is an anti-kinking device (1" PVC pipe beveled internally at one end) duct-taped directly to a 1" to 3/4" bushing.

 

20160723_224251_001_zpsuqgyj7pq.jpg

We've all done the thing where we reach into the hardwre store bin without looking and get home with a 3/4" bushing and not a 1/2" bushing. Now is the time to use it.

 

20160723_231936_zpsbv7bqzyi.jpg

Now we need to make some decisions. Decide the orientation you want your bolt to stick out. It should probably be at least 45 degrees up from the horizontal. Drill holes all around to lighten it up, but do not drill holes on whatever the "bottom" side is. On the bottom, make a slot about 2 inches long right at the front of the bolt. This is where the catch will lock. Make it wider than it needs to be, it will be much less finicky if this hole is oversized.

 

20160723_232331_zpsvusoazgh.jpg

Test fitting with the [k25].

 

20160724_084538_zps21nppuxk.jpg

Testing with the new handle. I used a 1-1/2" PVC "half piep" (really more like a 2/3 pipe) to snap directly onto the barrel. Note the stylish wooden handle that SNAP users seem to love. You can also just barely make out the hole in the bottom of the body tube; this should match up with the slot that was cut into the bottom of the bolt, so the catch can have access to the bolt slot and lock in place.

 

20160724_093535_zpstrlzo9pm.jpg

This is the guts of the catch, with cutting board sideplates holding everything in. Basically, the trigger is pulled, which rotates the catch itself downwards and out of the way of the bolt. The catch itself is triangular shaped and really just has a piece which pops up into the body tube and locks into that hole in the bolt. Just like an ESLT, make sure you made a slot in the body tube as well that lines up with the bolt slot.

 

20160724_103529_zps6njn2wel.jpg

 

20160724_103533_zpsn5axy9mh.jpg

 

20160724_103541_zpsto2nro2f.jpg

 

The 3/4" bushing in the rear makes it almost trivially easy to throw on a stock, and the 3/4" pipe is much stronger than the 1/2" pipe. Rubber bands act as the catch restoring mechanism, and create a spring loaded trigger too. The front of the sideplates are held on simply by zip ties.

 

This baby is pretty asymmetrical, but I kind of like it that way. The spring kinks up a little, but the anti kinking mech fixes that without using any guide rods. The spring is not reaching full compression (need to chop another half inch off the back) but has like an inch or so of precompression, gets 5.25 inches of draw with the [k25], and rocks roughly 200 FPS based on just ear-analysis, I want to test it at APOC and get hard numbers.

 

The blaster without a barrel and hopper weighs 1 pound, 15 ounces, so with a barrel and hopper probably around 2.5 pounds, and even that weight can be brought down if you used wooden sideplates or went ham on lightening holes, particularly in the rear where the anti-kinking tube is.

 

Overall, I am mildly impressed with the blaster. A hardware store hitter that can play with the SNAPs with sear reliability and without the need to order anything. Get a pack of springs from spiderbite and you're set.


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#354648 Looking back at 14 years in the LGLF...

Posted by Langley on 28 June 2016 - 07:14 PM


PS - I'm just going to say it right here and now. The LGLF logo is the best logo I have ever designed, for any group or organization, period.

 

Every time I drink with Ted and I get a little too sloshed he tries to talk me into getting it as a full-sized chest tattoo to match the t-shirts.  And every time I get a little too close to actually doing it. 

 

Here's the LGLF logo over the years, and some work Groove shared with us while he was working on the current iteration. 

Attached Thumbnails

  • LGLF02.png
  • LGLF03.png
  • LGLF12.png
  • 289052_10100167189373206_348576_o.jpg

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#353956 The STAN gun

Posted by KaneTheMediocre on 03 June 2016 - 11:49 PM

The S imple T ype A utomatic N erf gun.
 
Materials:
 
18" Schedule 80 1/2" PVC Pipe 5.85 (120")
 
30"+ Schedule 40 1/2" PVC Pipe 2.21 (120") 
 
12" Schedule Anything 3/4" PVC Pipe 2.86 (120")
 
2x 3/4" PVC Tee  0.44 http://www.mcmaster.com/#4880k42
1 ft vinyl tubing $1 (estimate, need to confirm at Ace)
1/2" CPVC 45 degree elbow 0.36
 
 
Duct tape 3.75 (1 roll)
 
Price for 1 with leftovers:  5.85+2.21+2.86+0.27+1.59+0.38+2*0.44+3.75+1+0.36 = $19.15
Bulk price per blaster (60 LCD, 16" magazine):5.85/6+2.21/4+2.86/10+0.27+1.59+0.38+2*0.44+3.75/3+1+0.36 = $7.55
Bulk price per blaster (6 LCD, 26" magazine): 5.85/6+2.21/3+2.86/6+0.27+1.59+0.38+2*0.44+3.75/3+1+0.36 = $7.91
 
The basic mechanism of the STAN gun is the well known hoppered blowgun.  The STAN gun is intended to take advantage of this amazingly simple and economical mechanism in a way that more meaningfully passes for a blaster.  There's still no trigger, and it's still lung-powered, but there are at least handles and a stock, as well as a flexible tube that prevents the user from getting their teeth knocked out in a collision. 
 
 The hope is that STAN guns help NIC-isolated war hosts to provide enough loaner blasters to start a community with normals.   There's no question that a traditional hoppered springer NIC primary is a superior blaster for a typical playing field and playing style (These are 50 ft blasters tops), but these are still good enough at what they do to have a role in an NIC war (Provided at least a LITTLE bit of cover) and enough WOW for a person who's never seen homemades to hold their interest.   The cost for 1 blaster is a bit deceptive, as very short lengths of pipe are required.  This not only means dramatic savings for making more blasters, it also makes it more likely that a given NIC homemade enthusiast would have everything needed to make a STAN gun already.  The wye is the only really obscure part, but we've all come to peace with the fact that we need to order a bunch online every once in a while.  Schedule 80 pipe can be hard to find locally depending on where you live and if you have a day job (Menards always carried in in Chicagoland, but the closest Menards to me in WA is in Wyoming), but you can always order it online. 

I plan on this evolving into more of a writeup than it is currently, but I always do, so we'll see.  In the meantime, the video shows you everything you need.  I recommend watching it, and really all youtube videos, at 2X speed.  It's in the quality settings menu.
 
Troubleshooting the feed:
+Make sure that the vinyl tubing is pushed in far enough to seal in the sch40 1/2" pipe but not so far that you can see it when you look in the top of the wye.
+Make sure your barrel entrance is as smooth and gradual as needed for your darts.  Some darts need more than others.  With Artifact darts, you need an extra-gradual entrance.  Sometimes tray style hoppers like Zorn's optimal wye are needed for springers, although I've always gotten blowguns to work without them.
+Make sure your darts are short enough.  Artifact darts are 36mm, and I think that's about as long as you can go with such rigid foam.  If you have darts made with very soft and flexible foam, you may be able to go a little bit longer if you want.
+Take the magazine, and ALL of the darts out of the wye, and put them back in and try again.  Hoppers are voodoo, sometimes this just happens.
 
 

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#347684 Do NOT Paint it Black

Posted by Aeromech on 05 July 2015 - 01:35 PM

Paint jobs have long been an integral part of cosmetic modifications of Nerf blasters, both homemade and modified stock blasters. It adds a level of individuality to a person’s blaster or company name if he/she wishes to market them. Legal and practical problems arise, however, when these paintjobs begin to resemble the color schemes of firearms, real or simulated. Metallic, rusted, black, flat dark earth, or military style camouflage paint colorations on nerf blasters are deleterious to the individual, the isolated nerf war, and the hobby as a whole.

Nerf blasters purchased from the store already resemble actual firearms, especially in silhouette, at a distance, or in low light. The Nerf Recon/Retaliator is one such blaster, and one of the most popular to modify into an imitation firearm, due to its’ close geometric resemblance to that of the military M4 carbine or popular civilian AR-15 carbine. The addition of an M16A2 carry handle or simulated carry handle on these toys contributes further to the outline of an actual weapon. Furthermore, tactical accoutrements such as slings, scopes, foregrips, and flashlights are not uncommon sights on todays’ Nerf blasters. These additions are largely innocuous, in that the underlying paint is still bright blue or orange or white, but do not help at distance or in low light conditions. Wars are often fought exclusively in the day, so this is not that big of an issue.

Posted Image
Figure 1: Nerf Retaliator modified to simulate M4 carbine [3]

The painting of one of these blasters is another story altogether. When the blues and greens and yellows are replaced with olive drab and desert brown and black, the appearance, as well as the law, swiftly changes on these blasters. What was clearly a toy can now be mistaken for a real steel firearm, even at relatively close distances. The same could be said of homemade blasters, which often can be mistaken for improvised firearms by jumpy bystanders with no knowledge of firearms or the strengths of common materials.
But U.S. federal regulations dictate that as long as the orange tip is preserved, the blaster is totally fine in the eyes of the law so long as certain markings are maintained, such as this one:

A blaze orange (Fed-Std-595B 12199) or orange color brighter than that specified by the Federal Standard color number, marking permanently affixed to the exterior surface of the barrel, covering the circumference of the barrel from the muzzle end for a depth of at least 6 millimeters.


So the argument can be made that if the orange tip is preserved, the blaster still falls within legal ground. While this may be true, the spirit of the game, and the perception of it to others changes dramatically. If brightly colored blasters or PVC homemade blasters are left in their original colors, or painted flamboyantly, a passerby to one of our wars will clearly see that these blasters do not pose a threat, and that the players are not looking to intimidate. Now if these blasters are painted black or desert brown, and a bystander sees one or more of these, there is an air of discomfort. To the ignorant, our harmless games begin to resemble para military exercises. Even if legal to the letter of the law, there is nothing stopping a bystander from calling the police, and having the players kicked out of the public playing area under some fabricated charge.

This is a major advantage that Nerf has to airsoft and paintball. The game can be played in a public park, without the investment of expensive equipment or specialized game fields. Even if the game itself is not to be regulated on a federal level, if local parks are made hostile to the wars that are often held there, we would need to relocate. It only takes one arrogant player to talk back to a passerby or one errant dart to hit a passing child to have us vilified. The culture of our game is dependent on the passivity of outsiders, and, as seen in broadcast media, our reputation has nowhere to go but down. If one catastrophe was to take place, our game may very well be regulated, and we don’t need to add any fuel to the fire by painting our blasters black.

Posted Image
Figure 2: Homemade Nerf pistol with clear plunger tube, and bright color [4]

Imagine if every game was required to be played in an airsoft arena. Months worth of notice would need to be given to arenas, and their schedule worked around. Every game would warrant additional payment to these fields or arenas on top of travel and potential lodging costs for those of us that drive long distances to Nerf. The spontaneous weekend war would cease to exist, and the few large scale wars we do have would be nearly impossible.

The moral of this article is to keep your blasters their stock colors, or paint them, “white, bright red, bright orange, bright yellow, bright green, bright blue, bright pink, or bright purple” [1]; keep them looking like toys. Let’s continue to be those geeks at the park with those weird toys, and not earn ourselves the reputation of troublemakers. Stay safe, stay smart, and Nerf on.

Disclaimer: I am not a lawyer, nor do I profess to have an expertise in the law in any way. I am in no way responsible for your actions. Please consult a lawyer before undertaking such endeavors. This article focuses on United States Federal Law, but the spirit of the argument may be extended to all principalities. For those in the U.S. I recommend glancing through the referenced material, particularly the first.

References:
[1] “Part 272-Marking of Toy, Look-Alike and Imitation Firearms.” Electronic Code of Federal Regulations. 23 Jan 2013. U.S. Government Publishing Office. Web. 2 Jul 2015.
[2] “Penalties for entering into commerce of imitation firearms.” Legal Information Institute. 5 Nov 1988. Cornell University Law School. Web. 4 Jul 2015.
[3] srsim2. "Nerf Paintjobs." deviantart. Web. 5 Jul 2015.
[4] Lucian. "Homemades Picture Thread." Nerfhaven. 27 Oct 2013. IP.Board. Web. 5 Jul 2015.
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#344901 The PullSCRT

Posted by Ryan201821 on 09 February 2015 - 05:57 PM

The PullSCRT

[video needed]

P-SCRT_FinalAssemblyMaster.jpg

Background:

+bow: http://nerfhaven.com...showtopic=10521
Purple Catch: http://nerfhaven.com...showtopic=24114

The idea behind this blaster was to replace the +bow by using 3D printed parts. It's much quicker to built, has no face diddle, built in check-valve, and costs much less to build in terms of materials and labor. This guide will also show you how to build The Purple Catch, which can be installed on any blaster with 1 1/4" PVC.

Blaster is designed to have 6" of draw.

Downloadable Files

Click Here
51 MB

Contains everything you need, stl's for printing, stp's for modeling, and a parts/cost sheet.

.ipt files are compatible with Autodesk Inventor 2014 or newer.

Essential Tools
-3D Printer w/ no less than 7x7x7" print area
-Scrollsaw or Hacksaw
-Drill press and/or power drill
-Dremel w/ cutting wheel or Mill/Scrollsaw
-7/64”, 5/32", 3/8" drill bits
-#6-32 tapping bit
-Scissors and/or file
-Screwdriver
-#6 Countersink
-Hot glue and super glue
-Silicone lube
-Safety glasses
-Vise and/or wrench
-Tape measure, ruler

Printing your Components

P-SCRT_PrintedParts.jpg

Handle - We usually do a couple extra perimeters for the Handle. If you are using newer versions of Slic3r (1.2 and higher), you can add modifiers to the object you're printing, which will allow you to alter settings for a specific section. For example, in this case we want just the top section to be solid infill, where the screws attach. The rest of the handle can be printed normally. If you need help with this, let me know. Post print, you need to drill out the hole (#6 pilot) for the trigger, and tap it. You also need to drill and tap the two holes on the bottom that attach the stock rod.

PlungerRodHandle - This part is designed to have 6mm walls at the thinnest point. Since we have a printer with a 0.6mm nozzle, this is five perimeters. You'll want at least those areas to be solid. Post print, drill out the hole where it attaches to the plunger rod (#6 clearance).

CatchPiece - Make sure this piece is solid. After it's printed, you'll have to file/sand each edge and surface down. Fit it inside the cavity on the handle where it's supposed to go to ensure it slides properly.

TriggerHalf1-2 - Print these normally, but you'll need to pay some special attention to these pieces afterwards. Glue each half together with super glue. After the glue is dry, sand/file the edges just like you did on the CatchPiece to make sure it fits nicely in the handle.

StockGuideFront/Rear - These can be printed normally. The hole in the front piece is an outlet for 1/2" PVC. Drill out all eight holes with a #6 clearance. On the front piece there will be some support material underneath that you'll need to remove.

Stock-Bottom/Top-Print - Print these with normal settings and drill out the 6 holes for the stock (#6 clearance), and the two on the bottom print where you'll attach screws to the bottom rod.

SpringRest/Back - Print both of these pieces solid. Drill (#6 pilot) and tap the four holes on the larger piece, and drill out (#6 clearance) the two countersink holes on the back piece.

PlungerHeadFront/Back - These pieces should also be printed solid. Drill out the two countersink holes in the back piece (#6 clearance). On the front piece, drill out (#6 clearance) the countersink hole, and drill (#6 pilot) and tap the two holes that attach the two pieces to each other. You'll also have to remove a small amount of support material from the front piece.

Tube & Rod Machining

P-SCRT_PlungerTube.jpg

Make sure your PVC is smooth on the inside. The majority of PVC we encounter is very bumpy and awful on the inside, creating unnecessary friction and a shitty seal. The larger holes on the top and sides should be 3/8". Countersink the two holes on the bottom from the top, through the larger holes. These holes attach your handle. All the small holes should be #6 pilots. Cut a slot for the CatchPiece using a mill or dremel. You can also use a scrollsaw but you'll have to make a large hole on the top to accommodate for the scrollsaw blade.

P-SCRT_1.25ThinwallPVCStockTube.jpg

P-SCRT_BarrelPlungerRod.jpg

P-SCRT_StubsMisc.jpg

Sub-Assemblies

P-SCRT_HandleAssembly.jpg

P-SCRT_PlungerHeadAssembly.jpg

P-SCRT_StockAssembly.jpg

P-SCRT_BarrelAssembly.jpg

P-SCRT_PlungerTubeAssembly.jpg

Final Assembly

P-SCRT_FinalAssembly1.jpg

P-SCRT_FinalAssembly2.jpg

P-SCRT_FinalAssembly3.jpg

P-SCRT_FinalAssembly4.jpg

P-SCRT_FinalAssemblyMaster.jpg

Questions, comments, flames, please post...


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