- → Split's Content
There have been 1000 items by Split (Search limited from 28-February 93)
This is an interesting design though. To market towards the looozars, they up the range (supposedly flat ranges too, which is nice). But then to keep to their safety standards, they increase the diameter to distribute the impact more. I'd guess the new darts have even more impact absorbing designed into the tips than streamlines (deforming the hollow tip absorbs most of the kinetic energy). However, to get that much energy to the dart while letting little kids used it, it sounds like they used a spring that's not very stiff, but is really long, hence the 2' plunger tube.
All that said, if those spec's are right, it's still of very limited modding use to us. We don't really want 10"+ long strokes, which limit rate of fire, comfort and, as it turns out, efficiency. This seems to be just as hurt as most blasters by being targeted to kids, which is of course unavoidable. It surprises me that any production company would openly suggest some capability for modding, since the official stance is always "do not modify this product."
[url=nerfhaven.com/forums/index.php?showtopic=23562]23rd [NJ] NJW12[/url]
[url=http://nerfhaven.com/forums/index.php?showtopic=23524]9th [PA] Gears' Spring Break[/url]
Anything not firing a Slug Dart
No stock sceptor?
What about having this war at a non shit field?
I know you're fucking around, but if millcreek isn't still flooded, that would be a sweet place to play. And a much better drive for me.
Ranges I am getting are 45 - 55 + feet with 1.5 inch single bb dome darts.
[old man voice]Back in my day, we just called them stefans![/old man voice]
Anyway, nicely done. Very clean. I like to see that there are still people modding the new guns.
I have to ask though, why didn't you put the coupler closer to the plunger tube?
As far as blasters, can I use my sceptor that shoots balls?
Send me a PM with your address, credit card info, a scandalous picture of your mother, and your social security number. Okay, I'm kidding about the social. And the credit card.
I'm in for two different categories. Do I get two rocketsszs? PM sent boss.
I guess I never commented on why and how the shell has that gap. The inside of the crossbow shell is only 1-3/8" wide. Therefore, by putting a 1.5" OD plunger tube (full size +bow tube, same ID as rainbow tube) the gap needs to be at least 1/8". That would disperse the gap throughout the entire body of the blaster, including the handle, and stock, making the blaster creaky and less comfortable. By closing the gap throughout the rest of the shell, it leaves that 1/4" gap along the front.
However! Despite the gap, these kits distribute the load of firing much better than any of the other kits. They distribute the load over the 8 standard internal supports, but also over the two new spacers. Also, instead of distributing the load through a very hard surface, it uses the rigid foam, which absorbs more energy and puts less stresses on your shell.
With regards to the empirical wear-and-tear from these kits, both Muttonchops and Gears have had crossbow kits with this spring, plunger and plunger head combination for over a year, without any of the foam or standoff additions. Even through heavy use, the internal supports show no sign of stress under the same load (same stroke, same spring). I am completely confident that with the extra support, these kits will work in such a way as to not damage the shell, while allowing a fast range game with hoppers.
Thanks for the questions! Keep 'em coming.
It won't really hold a thread, but you can drill it and put stuff in there. By nature it has very low tensile (pulling) strength, but it's pretty rigid in compression. This method, like most of the other ones in my crossbow threads, can be applied to basically every blaster.
That is damn clever.
Can the hardened foam take a screw normally, or do the air bubbles prevent that?
Nylon plunger rod
Polycarb scraps for handle and plunger head
Skirt Plunger head
Great Stuff expanding foam
Goop, e-tape, 1/2" screws (6-32), 4 washers, between 1.5 and 2" screw (6-32)
Copy/paste-able parts list for mcmaster
Total Cost (each):
~$25, depending on how much you pay for polycarb scraps
Your first step is to cut your plunger tube to 9" in length. I recommend making a batch of these at a time because of the time requirements and the materials used (covered soon).
Next is the new method. Following the can's directions, shake the can of great stuff vigorously for 2 minutes or so. Put the dispensing nozzle on the tip. This stuff is one-time-use per can, and will last only as long as you're using it within 2 hour intervals. You'll want to be doing everything at once here.
Spray a layer of the foam on top of your plunger tubes. Try not to leave any gaps, but don't worry if you do. Set a timer for 40 minutes.
After your timer goes off, put another layer of foam on top of that one. Set your timer for 1 hour this time.
Once this timer is done, peel back any of the foam that dripped too far down. If you let it cure for too long, it won't come off cleanly. Now flip your plunger tubes over and foam up the first layer. Timer for 1 hour. Typically you'll want 3 layers total on this side, with an hour between layers.
Let these 5 layers cure overnight. Do not let them fully cure (24 hours). While they're in this in-between stage, the foam is soft on the inside. You should be cutting out the body now.
Take your foamed tubes to your band saw. Cut off the overflow on the ends, then the tops, making sure to make those cuts parallel. Finally, cut down the sides. You need these cuts to be at the sides of the plunger tubes. Your blade should be grazing the sides of the polycarbonate. Here's the cut progression:
After this, we can set up our cuts for the supports.
Draw a line to represent the top of the plunger tube. Draw a parallel line 1/2" above that. This will be your top - make it on thinner side.
Draw a line to represent the bottom of the plunger tube. Draw a parallel line 3/4" below that. Draw a vertical line 5.5" from the front of the plunger tube, and another vertical line 8" from the front of the plunger tube.
Cut along the bottom most line for the first 5.5", then cut 1/4" below the bottom of the plunger tube up to the 8" line. From there, cut out the corner.
While these are still soft, mark vertical lines on both sides at these points (distance from front of plunger tube): 4.25", 5", 6.75", 7.5"
Take a dremel with a boring bit (correct me if this name is inaccurate, this bit it used to cut channels normally) and cut out in between these sections over the distance where there is plunger tube. This is where the crossbow's internal supports go.
Once you have those done, fit your internals into your shell and mark where the decorative holes in the shell are onto the internals. Poke a screwdriver through these marks and insert your standoffs:
At this point, you can add your bushing with e-tape, goop and a screw. You can now leave these assembly to fully cure. The foam will harden around your standoffs, making them very sturdy.
While this is curing, cut your plunger rod to 12", with a notch 2-7/8" from one end (location is the back of the notch, where the catch meshes). Drill and tap both ends.
Cut your spring to 7" in length, cut a polycarbonate circle 1-1/8" in diameter with a 5/32" hole in center, 1/8" thick. Cut your priming handle of choice.
Finally, sandwich your skirt seal between the polycarb circle (front) and a 1-1/4" metal washer (back) onto the end of your plunger rod. Next put on your spring, then your catch, then your priming handle.
Once your plunger tube is cured, put lube (I recommend o-ring lube) in the plunger tube and insert your plunger assembly. All together:
When putting this into your shell, the front will have a gap. You may need longer screws in the screw ports - use 3/4" #6 wood screws. Use 6-32 screws with matching washers into the standoffs through the holes to distribute the load of firing and keep the shell together at the top.
This is the first crossbow to be able to use a hopper to break 100' ranges.
If you'd like, you can add extra layers of foam to create more features, such as this example grip for a missing-grip crossbow:
Special thanks goes to Muttonchops for letting me use his pristine crossbow to make these kits.
The 6 kits pictured here will be available for sale later today.
Last, but not least in this section is reinforcing the plunger slides. I hear/tell, that after a while, if you don’t grab the plunger handle and pull straight back every time, after a while the rests may crack. Not really a big deal, but I want this thing to last forever. Four 1 1/2″ x 5/8″ x 1/4″ polycarbonate rectangles, sanded via dremel at the post points, hot glue layered on:
And here’s the left side after this section:
You can see here, that I actually Dremeled off the part that the spring rests push against on this half of the shell, and replaced it with 1/4″ polycarbonate. If yours is cracked or otherwise broken as mine was, I recommend doing this as well.
Replacing the plunger tube
If, for some reason (cracks, looks, seal), you need to replace the plunger tube, it’s not all that hard to do. Stop by your local homedepot, and go to the plumbing section. Pick up one of these:
It’s called a 1 1/4″ plastic Extension tube slip joint – 12″. It’s typically used as a coupler for bigger pipes. It’s perfect for our applications.
Start by cutting your plunger tube to the desired length, using only the narrowest part (right side in the picture). Mine was 7 3/8″ long, and it turned out dead sexy. I used pipe cutters to make a decently straight cut here, but they don’t work on the next part. Cut two, minimum 3/8″ width, rings from the next higher width section (second from the right in the picture), and slide them over your plunger tube. Use a combination of super glue and hot glue (again, in layers) after roughing up the plunger tube to attach it where they need to be. A 1/2″ Pvc coupler should fit tightly inside the front of your plunger tube. Use a rubber mallet if necessary to get it in there.
For cushoning and to fill dead space, I put a 1″ piece of sch 80 PVC into the inside half of the coupler, then put a few inches of 3/4″ pipe insulation (the length will depend on the length of your plunger tube) that I cut a length wise section out of, in order to get the proper diameter. This is very effective padding.
Screw post replacement
Filling shell holes and otherwise sexifying your crossbow
Inc a quick guide on how to paint
Without the tank, the gun looked like so:
I cut down the front around the plunger tube and where the tank was going, then used 1/8″ plexi to fill it in super cleanly.
I then filled the seams in with too much epoxy putty. I filled any other holes the same way – with too much, except for width ways. It will shrink, but you need to keep the width correct. It’s a good idea to do one side of the shell before the other, so that you can compensate for any mistakes. Then carefully and slowly sand the putty down to the same grit as the xbow.
Laying down the paint: I follow the words of Direct Threat:
“If you really want to make your paint work -
1. strip the gun bare
2. Wash it in as hot water as you can put your hands in (not hotter) using dawn (lots tried but it works best)
and you have to do it INSIDE and out. Otherwise oil from in will gt out and mess you up.
3. Sand with 800 grit- lots of sanding! then some more. How to know your done: When water “sheets” when rinsed AND your fingers (clean fingers) stick. Also there is uniform sheen and no shine.
4. Black vinyl dye
5. Start paint layers
7. More paint- it is THIN not thick – also now the metals and toners go on
Highlights include VERY thin use of clear to “tack” them down – this is not top coat coverage
7. Repeat number 6 as needed
8. Any “wash” techniques if desired
9. Cure time and sometimes heat cure
Big smiles…your done…it took a long time but the product is worth it.”
Cut them from other guns (I know most of you have AT2k shells just sitting around, and you definitely will if you’re integrating a 2k into this), then cut the post down to the correct length.
You’ll notice that these posts are extremely small compared to the xbow parts, so we need to compensate for the difference. Spray some silicone lubricant onto the corresponding xbow post-thing (anyone have a good name for this?), and hold the new post in the center of it. Now put an overflowing ring of hotglue around the new post, and hold it there until the glue has cooled.
Use extremely liberal amounts of hot glue to hold these in place.
SUPER HAIR trigger, swappable finger grips
Swappable trigger grips. One of the many gripes I hear about crossbows is the uncomfortable trigger. There really hasn’t been any standard way to fix this, and it often has to be redone if it’s ever sold. This allows you to switch out between several grips to fit whatever fits you most comfortably.
To start, just cut a 3/4 circle out of 3/4″ Sch 40 pvc and glue it onto your trigger (after a little shaving off of the top). At this point, you can make different grips out of bases of 1/2″ pvc. Pictured are a 1/2″ x Sch 80 and a 1/4″ x Sch 40:
You can really take this anywhere. They pop in and out, and can be glued in once you decide on the one you like. I stuck with a 3/4 circle 1/4″ x Sch 40 with a piece of cpvc on the inside shaved down where your finger goes. You can make it so your finger goes on the inside or outside, sticks out a lot or a little. You can curve the sides for your finger to curl around better; you can set it off center or a multitude of things.
Super Hair trigger.
I saw a “write-up” on crossbows, that explained how to make a hair trigger for the crossbow via a small paint image. He said that he tried it; I don’t believe him. I tried it. I’m going to show you how to do it. Keep in mind, the crossbow is already renowned for its awesomely hair trigger.
Trace the slant of the top piece of the trigger onto a piece of 1/8″ poly carbonate, then slide the trigger to the side and trace it again. This should give you two parallel lines. Put a horizontal line between them, and a vertical line at where you want it to end, then cut the whole shape out.
Now super glue that shape onto the trigger. (Here it is with my finger grip of choice)
You’ll need to cut the shape down of course. What I found is that making it a triangle with the thinnest point at where the catch is before you pull the trigger. This stops the misfires that happen if that point is too high, and still allows the trigger pull to be shortened. What happens though, is that if you do the next part – the integration with linked trigger – when you go to pull the trigger back the rest of the way to fire the secondary, the catch can’t travel up anymore and the trigger can’t pull any more. This leads to a rounded shape, which is ultimately only semi-effective, since the catch will occasionally get caught on the top of it. A complete solution would be the rounded shape couplered with a more powerful trigger spring, but I opted to instead remove it and maintain the light trigger pull.
Internal integration with linked trigger
Here I’ll be integrating a singled 1500 under the primary crossbow barrel. You need the normal 1500 internals, some 1/4″ tubing, and one or two tubing connectors.
The normal route is to use the connectors to run extra tubing between the existing tubing spots, but I preferred to just run the tubing straight into the tank. It makes the tank easier to place, since you don’t have to deal with that solid piece sticking out. To do this, just snap or dremel off the old tank tubing, and use a 7/32″ bit to drill about 1/4″ into the tank at that spot, then jam the tubing in and goop it.
Half a coupler, and glue it on as straight as possible (or at an angle to compensate for an angled cut if necessary). Cut the spot in the front of your gun for the tank and coupler as clean and, more importantly, as straight as you can. I made two brackets for the pump – one for the hole at the top, and one stabilizing one on the pump tube. Damn sexy if you ask me. Find the desired length and cut and connect your tubing.
For the linked trigger, you need some solid wire, not flexible stuff. Make a ring at one end around the sliding plastic piece and glue it down. Leave about 1/8 to 1/4″ slack between the end of the plastic piece and the end of the tank pin, and attach the wire to a 1/16″ hole in your trigger:
This system works extremely well, to all of you who said it wasn’t possible. It works as such: You pull the trigger back, pushing against only the trigger and catch spring, the crossbow fires. You pull back more, the slack in the wire ends, and you now feel the (strong) spring from the pin resisting your movement. Continue pulling back and the integration fires. You can pull the trigger back quickly and fire both; you can not have the xbow primed and fire only the 1500. It’s versatile. It’s powerful. It’s clean. Boo yaa.
Make sure both sides fit, and pull out your drill.
Pilot through the two pieces of metal and the plunger all at the same time, while they’re put together and on a flat surface. I used an 1/8″ hole, and #4-40 screws at 1/2″ length. Assemble. We’ll need to shave down the excess from the screws so that they don’t catch the spring. Move the plunger to your vise. Carefully dremel down to the washer. Here, you can see the first screw done.
Throw your spring on really quick, to make sure that it doesn’t catch on anything.
The next big thing in this step is to reinforce the back of the catch. Take that long aluminum stripping that we used some of for the plunger, and cut a 3/16″ piece off of it.
Rough up one side of the lip that catches, and fill it with super glue. Throw in your tiny rectangle, and clamp it down until the glue is dry. What you want to do now is to put a thin layer of hot glue over that. When that layer dries, do another, and then another. This will seal it in, and distribute the force from the spring moreso into the surrounding plastic and rubbery glue than before.
Next to cover here, is the plunger head. There are many things that happen to plunger heads, and I intend to show how to correct the most common ones, and how to get a perfect plunger seal, without electrical tape.
I’ll start with the perfect seal. It’s quite simple. If you’re using the stock plunger tube, use a 1 1/4″ Neoprene washer under the plunger head, like so:
If you’re using the replaced plunger tube (later), use the stock plunger head (no matter if it’s shriveled up or not, the skirt is the perfect size for a seal).
Another problem is if that white ring (see above picture) snaps. This most commonly happens if you shoot a lot, since it’s the impact that shatters the ring. This ring holds the spring in, and without it, the gun won’t work at all. The plunger head will get pushed off, and the plunger will just pull back with no resistance. To replace it, you need only a 3/4″ fender washer, cut just like so:
And there’s your replacement.
A huge, recently common problem is if the entire plunger head stem breaks off. This is more prone to occur if you store the gun while it’s primed, as the constant force on the stem weakens it over time, until it shoots off. The best way to repair this, is to pilot an 1/8″ hole about 1/2″ down into the center of the end of the plunger rod. Take a nice fat 3/4 – 7/8″ mounting or wood screw, run a 3/4″ fender washer, then your plunger head neoprene washer, then another 3/4″ fender washer (both uncut), and screw it into your piloted hole slowly until it can’t go any further. If you’re using the replaced plunger tube, a 1 1/4″ neoprene washer will do the job, but a 1 1/8″ one will be the perfect seal. They’re just significantly harder to find.
After all of that, you should be ready to assemble your plunger rod. Put the catch on first (metal side towards the handle, not the head), followed by your spring of choice – DT3 arrowshooter is most common, and is what I used. Then goes your plunger head, however you chose to do it.
Internal reinforcements, out the ass.
I’ll start with the basics, and move my way up on this one.
We’ll start with the spring rest. Here is my right side, cleaned up shell:
For this you’ll need two 1 3/8″ nails. Run a bead along the inside of the spring rest, and put a nail in there. Add layers of hot glue over it like we’ve done in previous sections, one after another, after the previous one has dried. You’ll need one in each side of the rest.
Now cut out a 5 1/4″ x 1 3/8″ rectangle from some sheet metal, and fold it like so:
Mark the slit from through the back, and make it too long. Finally, cut the vertical lines only. Lay down a liberal layer of hot glue where the piece needs to go, then place it there. Place hot glue on the back of the spring rest in the middle, then fold down the center onto it. Cut off any excess.
Next, is to reinforce the plunger tube rests. You’ll need eight 5/8″ x 3/8″ rectangles out of sheet metal. Hold each one up to a spring rest, and mark the curve, then cut the curve out:
Hot glue the rest, then use pliers to apply pressure to each piece of metal onto the rest.
Cpvc PistolSplat (Ps-800)
This is sort of a blast from the past. I first posted this to the LGLF blog in 2008 as a help to beginning nerfers so they could spend less time agonizing over mods and more time nerfing. Long story short, it's not on that blog any more, so I'm putting it up here. There will be a couple of other threads like this coming too.
Pistol Splat (can be found at Spencers or online):
Total- about $15
Hot glue gun
First, cut through the top and bottom of the red cap at the front with your Dremel. You will also have to cut through (or otherwise remove) the cap at the end of the feedport. Remove all screws in the side and open the blaster.
You will need to remove the gray piece in the middle that pivots, as well as the sliding piece at the front:
Pull out the plunger tube:
A spring may fall out when you do this. You can throw this away; it is only there to weaken the gun.
Put a layer of hot glue around one end rim of the cpvc coupler, and slap it onto the black end of your plunger tube. Making sure it’s centered and straight, add another thin layer of hot glue around the joint. Once that layer dries, put another. Layering like this adds tensile strength, making your mod last significantly longer.
Replace the plunger tube where you got from. If your cpvc coupler doesn’t fit nicely inside, you may have to sand down where it goes using the Dremel. The sizes of the couplers vary, but mine fit in well without needing any further modification.
Put the two halves of the blaster together, and replace all of the screws.
Cut a 4-5” piece of cpvc (if using stefans or converted dart tag darts; optimum length will vary. Experiment! Cpvc is cheap!) and push it into the coupler via the front.
You’re done! You should have a superb, primary worthy pistol at this point. It’s not the fastest or furthest shooting thing out there, but it beats out most, and it’s simple and reliable.
Some tips on use:
To load, pull out the cpvc, put a dart in the back, and place the barrel back into the coupler. To prime, pull the lever arm up and push it all the way down. And to fire of course, pull the trigger!
The gray piece from the center that we took out was the trigger lock. Do not dry fire the gun (fire the gun without a dart in the barrel). If you do prime the gun and need to unprime it, pull the lever all the way back, and pull the trigger. Then slowly lower the lever.
Do not store the gun loaded or primed. This will deform your dart and weaken your spring, respectively.
I'd like to see an overview shot of the plunger rod and updated plunger head. One thing though, - What's keeping your plunger rod from turning? The strings in the back?
We were having a discussion on whether or not there would be enough surface area to make a good seal, so I did the geometry.
The arc length over which the two tubes are touching (and therefore make a seal) is L.
L = 2*2*pi*(ri + w)*arccosd(ri/(ri + w))/360
ri is the inner radius of the inner tube (1/2" for 17/32 brass)
w is the wall thickness of the inner tube (1/64 for 17/32 brass)
For 17/32 brass, this arc length is only about 1/4" total, but if you use something like 1/2" ID 5/8" OD plastic tubing, the arc length is about .53" That's a surprisingly good number.
(It doesn't matter that much, but if you need the surface area for the whole seal, it's just the arc length times the length of the half pipe.)
A normal mill or even a drill press with cross slide vise and mill end bits could be used to make these precise parts pretty easily.
Nice work guys.
I am by no means an authority on this war, but this will be my 4th Apoc and hundredth or so war with Vacc and this group of Jersey nerfers. The dart restrictions are there so we don't need as much restriction on blasters. Most (all?) of us use homemades as primaries that will shoot well over 100' on average; your triple shot will be fine. The restrictions will likely be on homemade airguns, singled cobras and jobars (toilet cleaners) and maybe singled titans (including "chimeras").
...what are the standard gun rules for APOC? I have a Triple Shot, some antique blaster from before time itself. It can load single suction darts, and I dunno if it's overpowered or what.
Also, if eye protection is required, do standard polycarb frames count? Or are safety goggles a must-have?
Polycarb safety glasses have historically been fine. Shatter resistant is good, OSHA/ANSI safety rated is better. Several people have gone for full chemical goggles, others have opted for sunglasses, and a few of those sunglasses have gotten broken.
Edit: any date works for me.
Canada has been having international wars fo' evah. Brit = pretentious?
Guys, we just won "Shot of the Week" on Nerf Nation's Facebook page!
Here's the direct link
Note: You have to have an FB account, and Friend 'NerfNation' to get access.
Grats on the war though. Sounds like a decent time. What was the final attendance count?
Edit: Response to below, since the kid clearly does NOT understand this.
To find the last time someone posted, click Search in the top right. Type in the user's name in the "Filter by Member Name" box. Under "Result Type" click "Show results as posts". It will show the first 1000 of that user's posts, from most recent to least. The top post is their last post. Does exactly what you're saying, without any script, let alone whatever misconceptions you have about college being true. (Seriously, look at this. They're common, and easy to make.)
Even quicker, if you're just looking for all posts by a user, click their name to see their profile, click "Profile options" then "Show user's posts."
Other than that, it looks pretty good, as always. Jlego guessed, and I agreed, that this was moved from your sekret forumz?
How many shots are you getting from each fill? What's the parts cost on this thing?
Well, you have sort of contradictory requirements here. You want low energy input (not a lot of pumping, easy to reprime, tank isn't too big - "NOT titan tank") but also want to use inefficient setups to yield good ranges (high energy output). Stock darts + multiple air flow paths + good ranges. There's really no reason for you to mention how much you overpumped salvo tanks yet again.
Split, your work always amazes me. I'm not sure, but I think you misinterpreted the project in a few ways. It will use one exhaust tank, (not 4 or 6 like in the pictures you showed me). The one tank will feed 4 separate short barrels, as I use a variety of only stock darts (not stefans). I am familiar with salvo tanks, as you sold me two. However, I did not get to do much testing with them, as ones seal broke after 3 shots, and the other one exploded, and came inches from putting NMR brother in the hospital, and put a dent in the floor. As I have mentioned, this isn't your fault, and I dont blame you at all. I did not realize 10 magstrike pumps would do that, as I overestimated the volume of a salvo tank.
Since it is only 1 tank, feeding 4 short barrels, do you think a salvo tank would have the air volume and release rate to fire the with usable power?
There isn't going to be a single tank that you can make semi-auto to feed that setup without having either a huge/high pressure external tank or an entire HPA setup. Just throw a four barrel setup on a high air output springer (or airgun, if you really want). Besides, if you're going for semi-auto, with that setup, you'd have to reload all of the barrels every time = not semi-auto. If you haven't picked a solution by now, this has devolved too far into a concept thread.
So, to make this a semi-auto 2k, you have some sort of external tank/input. This can be HPA, or a hard tank (with or without a regulator), or a bladder, or a compressor or whatever. This tank routes into some open/close valve. The magstrike/powerclip trigger valve, for instance. These are common. Depending on how fast you want your semi-auto, they don't need to be particularly high quality or high flow.
So the air routes into this valve, and the output of this valve goes to the 2k tank. No check valves needed. When the firing trigger goes forward, (the 2k tank pin isn't being pulled anymore) the trigger pushes into the valve. The valve opens, the external tank sends air into the 2k tank. When you start pulling the trigger again, the trigger is no longer opening the valve, and the tank is full of air, ready to be fired. Pull the trigger all the way, it fires. It's a semi-auto 2k.
If you don't want to do the timing and everything of getting the trigger to hit the valve at the right time, you can just put the valve I was talking about somewhere else, and to fire you pull the main trigger, let that go, then hit the valve button, then let that go. Repeat for semi-auto-ish. I can't find the (THIRST?) writeup that had this setup.
Even simpler, just hook the input up to the tank and pull the trigger quickly. Here's a thread with that from almost 7 years ago: http://nerfhaven.com...?showtopic=2840
Semi-auto air guns are icky. They're pretty simple at this point, I think people are just intimidated by the prospect. Hope to see yours working! Let me know if you need help on the calculations for external tanks. I made a nice spreadsheet to calculate the volume/pressure a while back, but it's pretty bland and off-topic, so I won't post it here.
If you know of most blasters, you've heard of the Big Salvo. Well, besides using the tanks, it is a self contained blaster. It's four shots, staggered fire (pull the trigger a little, fires the first tank, pull more, next tank, etc), and the tanks with a plugged pump can launch three to four 1/2" darts 80-90' easily. It's not really that war practical, but it sounds almost exactly like what you want, with little work (re-barreling and plugging the pump). (Draconis also suggested this solution)
(Thanks to Carbon for the pic)
If you really need it to have a semi-auto trigger and be an airgun, take a hornet and replace all of the tanks with big salvo tanks. It has been done before and works pretty well. If you want to fill it faster, switch out the pump.
^^Ice Nine's beasty
Lastly, the most practical (and coolest) solution is already in the directory. Check THIS out. This thing with 1/2" darts is a monster. (Boot suggested a similar solution in his last edit)
And weaker than you think.
Broken SVT recently very kindly introduced me to the triple strike tank. It is a large backpressure tank, larger than that of a Big Salvo, but smaller than a titan tank (it is rare though)
It's actually only one more process, which is easily linked. The trigger pulls the pin, when the trigger goes forward again, it hits the fill button. Some might even call that easier than the check valve setup and finding particular valves with the right flow rates. Neither setup is difficult.
If you really are going for semi auto you should use a back pressure tank. With a pin tank semi auto setups require multiple processes and valves, while in a setup like the Mirage-SS a single simple valve can be used to efficiently trigger a backpressure tank semi automatically.
There is too much blanket statement here. See the solutions I posted above in regards to how simple the project actually is.
Regardless, to get a semi auto shotgun spread you will need a Massive fill tank, anything large enough has to be fitted to a backpack, otherwise I doubt any more than about 3 shots per fill is possible (unless you are using some insane HPA or Paintball tank with a regulator.)
There is only one line of these that uses an airtank (most are push-pull) afaik and it's a pin-valve.
A final possibility could actually be the marshmallow blaster, I'm not too familiar with them, but I think they operate off a backpressure system or something similar.
The LBB (blast bazooka) is virtually identical to a 4B, except that the pin is made of plastic and the tank body is a different color. The Buzzer Bazooka you may be thinking of does have a similar shell to a 4B, and is backpressure, but the tank is tiny. Smaller than a hornet tank I believe. I've owned a few.
Also there is this off brand BBBB equivalent called the "blast bazooka" (or words to that effect) which has a tank just shy of the BBBB and operates off a backpressure system.
That said, there's no denying that it'd be difficult/expensive for the rest of the community to replicate, much like Kane's blasters with milled and lathed and solid aluminum parts.
Agreed on this one, as long as it's not entirely flooded.
With the right mix of participants pushing the pace it might just work. I think it's hard to say until we try it.
Gears and I are busy on the 12th, will almost definitely not want to nerf on the 19th, and he's almost definitely busy the 19th anyway. I vote 26th. Would definitely miss bpso though.
It gets a bit more complicated here. If you have both of those o-rings on the same shaft ("rod OD" doesn't change), the o-ring with the larger ID has more room to move around, so the rubber material doesn't need to compress as much (it'll just move into the empty space). In this scenario, bigger ID is better (might be difficult to keep a good seal though).
Would this still be the cause of extra friction if the OD of the o-ring wasn't compromised? For example, using a 1/8"x1/4"x1/2" and a 1/16"x3/8"x1/2" (notice only the OD stays the same with a wall thickness change). I assumed it was a surface area change, rather than a o-ring deformation/compression change, because in theory they should be compressing the same. That thought assumes you match the correct OD rod to the same ID o-ring.
If you have each o-ring on a shaft whose OD matches the o-ring's ID, the o-rings have to compress the same distance. It's easier to compress a big object by 1/2" than a small object by .5", which is probably obvious, but comes back to materials science. Since the thicker o-ring has more material, and they both have to compress the same distance, it'll be easier to compress. In this scenario, the thicker o-ring is better.
Close, but not quite right. For the sake of having the correct information, reducing the outer diameter (OD) of the oring actually reduces the normal force between the oring and the surface, thus reducing friction. Same effect, different reason.
3. Using thinner wall thickness o-rings will reduce surface area, once again, reducing o-ring contact, thus reducing friction. For example, switch from a 1/8" wall thickness to 1/16".
If that doesn't make immediate sense to you, imagine the thickness of the o-ring as a spring. If the OD is 5/16", but the hole it has to fit into is only 1/4", the OD will have to reduce by 1/16" - it'll have to compress. Because it's acting like a spring, the force it's pushing back with as it's being compressed increases with the compression distance. So if the o-ring is only 9/32" (in between 5/16 and 1/4) it'll have to compress less and will exert less force on the surface that's compressing it.
As for this particular issue, those look like stock parts to me, so they probably fit fine and just need some lube. See Captain Slug's thread about lube, already linked in here.