Due to absence of TED, Jaxon is the best

I will be there.

STL Files are now public: https://www.thingive...m/thing:3223214

Hardware list: 

First "production" unit has shipped

And I have my first set of chronograph data.

What blaster would you compare this to in size? It looks neat, but I'm wondering how usable this would be as a sidearm.

It's nylon-covered elastic cord, typically used for bungees. 3/16" is the specific size I designed around, but I'm using 1/8" for the accessories. For further novelty it is offered in a variety of colors.

17 inches overall length (1.1 stryfes)
10kg max load (3 bands)
Top-slide prime (of the plunger and ramrod assembly)
Hardware Kit Price: $30
Assembled Price: $70

Planned File Release Date: November 25th
Current fps avg: 122 (with an unsealed breech)

Hardware kit will be: Barrel, Ramrod Core, Plunger Tube, 123 o-rings, 012 o-rings, elastic cord (1 or 2 sizes), two 13-1/4" length of 10-32 threaded rod, 4-40 screws, 10-32 screws, hex nuts.

The plunger catch surface is way at the back end of it so it won't be compatible with typical compression springs. At a later date I will look at what possible small OD springs could be used that would fit inside of the catch surface portion of the plunger, but that would be an aside.

The elastic cords are really really cheap compared to steel springs and changing the spring load on this thing is as easy as opening the fore-end and taking off or adding another band. And there are alternative options for band types and materials to toy with as well.

I have been working on this quietly for a few weeks now. I wanted to wait until it had some tangible results. This is largely and experiment in reduced build cost, and this is looking to be the lowest material cost blaster I have ever made. Even cheaper than DCHAP or any SNAPs I've ever built.

STL Files: https://www.thingive...m/thing:3223214

Takedown magwell has made assembly and packaging significantly less stressful, but not any less time-consuming.

Both secondary ammo type designs are now finished and working as desired. Rival file set has been updated. MEGA file set will be updated later today.

One week to go

Oh yes

What about silicone safe wd40, it works well (for me) on air blasters, and springers

"wd" stands for "water displacement". It's not an actual lubricant, but rather and cleaning/isolating solution. And as such its base component is typically a solvent. The aerosol components from spray cans are also not safe for application directly onto plastics.

You are better off using a clear silicone grease with as few additives as possible.

There is a rather active Nerf group in NYC.

Same weekend as EndWar, which I'm only sort-of attending so I probably won't be able to make it.

16 attendees. That was fun.

Boy it was cold.

Let's do it again in a few months.

You don't really have to start from a blank sheet if all you want is a shortened Caliburn. You can just trade available plunger stroke for spring compression (and as a result slightly less deadspace). You can also shorten the ramrod a bit to gain a little effective barrel length.

Your multi-catch plunger concept however is really interesting. And that's one thing that a diameter increase can accomplish. Given that the Caliburn was designed with the option of using Schedule 40 PVC for the plunger tube you probably have room in the stock area to use 1-1/2" ID 1-5/8" OD tubing for the plunger tube by just redesigning the pieces for the stock.

Waffle tips are LESS affected because they're really heavy.

The SCAR barrel is primarily compensating for not having a completely ideal barrel length for a given dart. But ideal length is a kind of nebulous thing that has a lot of variables, so having something you can adjust slightly is beneficial.

I'm going to guess that they are in inches, so you need to scale them by 25.4 in your slicer software.

This is a question you should ask the seller of said motor.

If you make some small changes to the trigger arm it will be easy to print upside down and will come out really nicely. Just draft a 45 degree angle into the surfaces in these two locations.

You don't need to include two pumps if you simply use a wye fitting and then an inline check valve for each tank.

And to make those shell parts less challenging to print you may want to consider some mid-line pieces for the shell so you can cut down on overhangs and bridging a bit. You may already have figured that out, but it's really hard to tell where the part boundaries are in the renders.

I have not gotten around to doing that yet.

I think the only functional concern is that the sequence will be off in the event that the user decides to load more than one dart into the breech. Could you add a switch that the foregrip triggers when slid back, and then depletes the count by one when released by the foregrip sliding forwards again?

That could be done without changing any of the code. You would simply wire that switch as normally closed as a replacement (or in tandem) for the trigger switch.

What is RSVP deadline?

There's no deadline. Any advance notice is helpful.

Lots of things to cover. First, I've documented every tool and step involved in producing hardware for Caliburns.

https://imgur.com/gallery/MpC55

Second, I am working on a Rival remix as well as a Mega remix.

Third, I will be giving away Caliburn #295 on Reddit this weekend to announce the planned charity auction of Caliburn #300.

Fourth, I forgot to mention that the +bow celebrated its 10th Anniversary in December.

Best I can give you is this.

That's a 1-foot ruler.

March 17th 2018
9AM to 1PM
 
Bruin Park
415 Van Buren St
Herndon VA 20170
 
50/50 NIC & Superstock
BYOD (Bring your own darts)
 
Cheap lunch to be provided for those that RSVP

 

Another option would be katana mags but keeping handle angled while the mag straight.

That's not feasible. The darts in the top of the mag wouldn't be inline with the barrel so they couldn't be ramrodded into it.

If you give it front an rear tabs so that it mounts to the threaded rod inside the mag well instead of bolting onto the side of the magwell it could be installed on either side.

Would require rethinking print orientation or maybe splitting the shell into two parts though. Otherwise left-handed users could simply mirror the file and print it for the other side.

Stock_Alt5 and RAIL_TOP now include two holes for spring pins that will prevent the rails from rocking side-to-side. These changes have been updated in the Ayy LMAO and 120mm build plate remixes as well.

https://www.thingive...m/thing:2376150

Yes, integral mag in the grip because that won't take up as much internal volume as having to accommodate a removable magazine. The working concept for me to design from now is what Meaker suggested. The backstrap of the grip will hinge open allowing you to reload the whole stack of darts at once.

A loading gate being possible or not is going to depend on how the breech gets revised now that it doesn't have to fit within the feed lips of a removable magazine. But I don't see topping-off darts as much of a priority.

The only thing I will be sad to see go is the novel trigger guard that doubles as the mag release. But that going away provides me an opportunity for a more rigid structure between the grip and plunger tube.

Fifth test print and I'm still hating it. It's not terrible, but it's enormous so it doesn't let your hand wrap around it intuitively.

So now I have to either go back to custom printed mags and refine the current design, or switch to an integral mag. I'm leaning towards an integral mag simply because it allows me to avoid having to supply potential customers with extra magazines. And a sidearm with a proprietary or expensive magazine would be pretty dumb if it's not something that could be easily adapted to a primary.

Are pump grip 3d print failures on the caliburn an issue?

They haven't broken under normal use. They do however break if some of the screws escape and the end user doesn't notice and continues using the blaster. The rear screw holes in the printed part will rip out eventually if those are the only screws installed.

 My remaining hesitation with this project as it stands is still that slide-prime is ergonomically awful, and you are asking the printed grips to bear a huge offset load as a result of that mechanism. I've also discovered that the lanyard cable I used to make the Piranha (and is subsequently used in this design) is in rough shape and being stretched by a spring for over a year. But given how cheap they are it's probably something I'm just whining about and shouldn't be holding me up.

To start printing the prototype for this I just need to buy another small printer.

Popped open a stapler this morning, and immediately thought "why not make a magazine follower that works the same way this stapler does with a standard extension spring?"

That would make sense for the GRIP ITSELF to split open and allow you to reload the internal magazine by just stuffing the darts in. And that would mean you could reload your pistol without having to have proprietary mags.

The downside is that your follower now has to have a linear guide feature on the side opposite the extension spring, or the extension springs have to be to each side of the follower. Both of which are arguments in favor of using a rubber band instead of a spring.

Anywho, enough excuses and whining. I'm currently printing the fourth revision of the grip. If it fails to be comfortable this time I may have to give up on Katana mags.

If the trunion piece that the barrel attaches to had a more robust connection to the plunger tube AND secures itself to the barrel more rigidly the barrel itself could be used as the slide for the front grip.

This is of course assuming that the barrel material is thick enough and strong enough to support that offset load. But it could be supplemented with another nested tube over it. The design could be revised slightly to completely negate the need for slots.

Lastly, I think it's a terrible terrible idea to transfer the shock from the plunger slamming into the bolt through the bolt itself. Your ramrod is not going to be strong enough to handle that impact and it will break. The ramrod itself is only strong enough to handle loading darts, and unless you make it out of aluminum the force of the plunger slamming into it will destroy it. You also WILL NOT be able to reliably feed darts through the middle of that o-ring anyways as it will add considerable friction to the process and could peel the foam back from the heads of the darts.

I've been fussing with this intermittently at work for the past month.