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There have been 412 items by shmmee (Search limited from 09-June 93)
I really didn't expect this to work - hence the overly ravaged screw ports and zipties.
8" pegt barrels, RF 20 bladder double layered with bike inner tube to increase pressure (still needs a bar across the front to trigger the overfill safety valve), dual action bike pump...
Rear loading hole with sch 80 pvc dart guide (still needs to be reinforced with more than just hot glue)
Internally it has a BS tank, and is operated by a clippard MAVO-3 valve. It vents (fires) the BS tank without venting the reserve bladder. The seal is pretty good. I just took the linkage that ran from the old pt to the turret, sanded half off till one side was flush and connected it via hose to the bs tank. Not shown are a pair of springs I had to run from the back of the turret anchor to the trigger.
I get 5-6 quick shots per fill, grouping around 80' in range.
Click the pic to see a firing video:
Precision cutting and pasting:
It still needs more putty, and a new paint job. I ripped the smdtb (spider man dart tag blaster) off of the shoulder last night, and hope to integrate it a little more cleanly by replacing the valve with a blast button, and hiding the pump - or a slightly better pump inside the collapsible stock (so compressing the stock pumps the smdtb). Once done the 3 blast barrels should sit flat on the side of the shell without the brick of tubing beneath it.
Load and prime all loaner blasters and line them up along a center line in the field. Personal blasters may be loaded but un-primed and may be held by their owners. This game was played on a basketball court and the court size was just about perfect. 6 tables were laid on their side as barriers (3 on each side - optional). Small piles of darts are placed behind the 6 tables.
Start with some brief instruction on blaster operation - especially the clip fed ones. "POINTY DARTS ONLY". I lost count of how many screamers I had to pound out of clips.
Line everyone up and count them off into two teams. Teams start touching opposite walls of the court.
At the word "go" teams rush forward to either grab a loaner blaster (hunger games style) or touch their personal blaster to the center line. Play begins immediately.
People with dart blasters may not progress beyond the center line. People with ball or arrow blasters may progress 5' beyond the center line to fire. Swords were originally given the right to completely penetrate enemy lines, but that broke the game and all swords were removed.
Once a player is shot they drop all ammo where they were standing. With their blaster in the air they walk to the center and place their loaner blaster on the center line (they can always choose to hold on to their personal blaster) and then keep walking to the enemies back wall. Once they touch the back wall they re-spawn as a member of the opposing team. (like blob) Their first order of business is to risk life and limb grabbing a blaster from the center line.
Play ends with one lonely hold out getting massacred by the rest of the group.
Rounds lasted about 30 min.
Why it works:
Dropping all ammo at death discourages hoarding.
Dropping blasters at death encourages people to try many different blasters and keeps people from getting stuck with "the crappy gun" for too long.
Having established "team sides" avoids the "what team are you on?" confusion of many other team games.
No one sits out so everyone stays engaged. The rules are simple enough that players can govern themselves. I actually spent 90% of the night playing instead of refereeing! (10% of the night was spent clearing taggers out of clips...)
Granting 5' of approach for balls and arrows makes them a serious asset. I spent most of the night looking for my ArrowStorm.
The larger team will handicap themselves by depleting their ammo.
The smaller team is handicapped with the difficulty of getting a new blaster without getting shot.
For large groups where large amounts of loaner blasters are used (or participants are willing to let other people use their blasters) - this game type absolutely rocks!!!
-Your blaster must shoot standard "nerf" ammunition. This means any current acceptable homemade ammo or Nerf stock darts, etc. No death darts, paintballs, airsoft, or any of that bullshit. This shouldn't be hard.
Are discs now considered standard "nerf" ammunition? Laugh all you want, but I'm thinking of welcoming the vortex line by doing a homemade disc shooter.
My child hood dream was to work with hasbro's R&D team designing nerf blasters. It's been exceptionally cool to see that as modders we really aren't too far off from where they start their designs too. They have more resources once they get to the production stages, but the early builds? It's poly carb, hot glue a 3d printer and what ever they've got laying around. I'll be geeking out over these pics for days.
I'm no gunsmith, but ports should be placed close to the tip of the barrel. I'd guess towards the last 1/2" to 1/4". Should be easy to clean out with a small knife, or hobby file. You are right though, there is definitely a right way and a wrong way to deburr drilled ports holes. My first instinct would be to grab a .5" drill bit. But if the drill bit expands the barrel ID enough for air to pass around the dart - you've defeated the purpose of the ports.
Only problem with drilling ports in a barrel is deburring the inside.
Secondly, the initial (and objective) testing I've done with rifling (comparing a gentle 18:1 twist, a tight 9:1 twist and a smooth bore have been so obviously against rifling that I've had a tough time forcing my self to set up the "precision shooting through paper test" I promised everyone and gather hard data. The darts weighted with a #6 washer swam like a fishy when shot out of the rifled barrel. I shot a heavier silicone head dart, and that looked like it flew perfectly straight, but it almost torqued the head off after the second shot. It's possible I'm not using a heavy enough dart. I think I'm going to have to wait till my 3 rd generation silicone head darts are done before doing more testing. They'll have more surface area to bond with an may be able to handle the stresses better. They'll also be heavier than the #6 washer. I also added a ls spring to my pas, which allows me to add another 2 inches to the barrel (confirmed by comparative testing 10" to 12") So the fishtailing with the 10" rifled barrels may be caused by the increase in power and not the rifling. I could add ports to the tip, but I only want to change one variable at a time while testing.
Ooh! Porting a barrel may be an easy, effective way check your barrel length! Coat the ports very lightly with dish soap or other bubble blowing solution, and fire a dart. No bubbles, or bubble solution inside the tip barrel = too long of a barrel, you're drawing a vacuum before the dart leaves the barrel. If you get bubbles, that means there is excess pressure that could of been used to accelerate the dart. If it just sputters violently, it's too short. That's purely theoretical of course. I don't know if ports on a barrel can even blow bubbles. Perhaps a similar test can be done with a weak tape (painters tape), or glitter/chalk line dust. The chalk line dust may work better with only a single small port drilled.
I've found panthers and jolt esque' blasters to be a fantastic fit for smaller younger hands. The mechanical advantage gained in air powered blasters is a huge assistance for smaller arms. Give a small kid a titan to play with and you'll be his hero for the day. Since they can be pumped on the ground like a floorstanding bike pump any kid who can lift the thing will feel like the biggest bad*** ever - and you don't have to worry about them loosing an eye if they decide to shoot themselves in the face. (which will happen!!!)
Ducnha, you're absolutely right about avoiding clip fed blasters and slide to prime blasters. Simple front loaders are the way to go for young nerfers.
The back cam stops the foam - measuring the length as the front cam (with attached razor blade) spins around and cuts it. A wet-dry vac provides suction that feeds the foam. In the full speed operation video it cuts 100' of foam in 3min 44 seconds - though the drill battery was almost dead at that point in the night. With a full battery on low gear (high gear makes it jam up) it cut 100' in a little over 2 min.
Slow operation video (click to view):
Full speed operation video (click to view)... Photo bucket refuses to let me upload over my current slow internet connection. I'll have to get it up once I get back to a more stable connection.
Ends come up perfectly square, length is incredibly consistent. It's a beautiful result!
Write up is pending - but coming. Right now I'm focusing on the production and sale of cut blanks. (Shameless plug warning)
pre cut beige foam sale link
Fantastic war, as well! It was great meeting so many new faces, as well as seeing a few familiar ones as well. The guys that flew in from the east coast were all studs. I really need to make it out to an Apoc someday.
That was a fantastic venue! It had the best mix of close quarters and long range I'd ever seen. I absolutely loved the freeze tag and lunch time speed rounds. I'll definitely be bringing them back home to play in Utah. It was hilarious watching the younger nerfers absolutely dominate the speed rounds! Watching the little lady with the single shot paint ball pistol own round after round was especially incredible.
- I've booked my hotel room (Garden Inn & Suites - if any other out of towners feel like taking the place over with me.) I've e-mailed them asking about a potential group discount but haven't heard anything back.
I'm still looking for more direction on darts and blasters. Who is going to be having the final approval for field use? Is it still SCUN?
I'm hoping to run with silicone ammo again (I'll be willing to send out samples of gumdrops 2.0 and (once I complete some more development) 3.0) I'm also hoping to run with a modified air blaster - but I know some nerfers (specifically on the east coast)have significant reservations about those. Dead space in the pump tube physically (and permanently) limits pressure to 15-20 psi, I also plan on reducing the tank (it's currently at the stock volume which is huge!). Once done it will have a 3 round burst RSCB and other innovative features. I know it won't be granted approval via the net - I'm just wondering who I'm going to need to be sending dart samples to / bribing for approval.
I'll be sure to bring back-ups just in case.
P.S. I'll be driving from Salt Lake City to 'geddon. If anyone between here and there or can get to SLC on Thursday the 19th (my departure date) would like to jump in /carpool/ pitch in on gas let me know. I've currently got 3 (seats 4-5) in my car but can take the van (seats 7) if needed.
Historically 'geddon has been friendly to some of the more creative darts. I'm hoping they'll continue that. I'd like to introduce a new re-development of Gumdrop darts (gumdrops 2.0).
Any rules on darts and blasters yet? I'd just like too...plan ahead.
I might make a slight suggestion here. To remove the step of cutting of the mold later, it might be advisable to mold in this fasion:
First, dip/coat the part as needed. Then put the part down in enough oogoo to cover half of it. Insert some small blocks of wood to use for registration. The part and blocks of wood should be sticking halfway out of the oogoo. Cure, then use more oogoo to make the other side. See here for more details of how you'd do that, only with chocolate:
But personally I'd avoid all that fuss and cut the mold instead, preferably by doing a two-step pour, where the top layer has some dye in it. You'd still get the benefit of curing the whole batch at once, with an obvious color gradation to follow so as to know where to cut.
Taerkitty suggested this on Nrev. It should make things much simpler. He also suggested putting on a coat of vasoline to any surfaces that we don't want to be bonded. That should really help avoiding the difficult slice.
The problem with oogoo casting very large objects like cross bow shells - is that there is some shrinkage as the oogoo off gasses. More so with the addition of mineral spirits (just some bob predicted this back when I first started working with oogoo). With small parts it's not too noticeable. At the scale of a crossbow shell, it would probably be a deal killer.
At this scale - for the sake of cost and repeatability - any one interested in casting very large pieces should really consider looking into "sand casting". It's an old forging process still used today. Sand is mixed with oil till it sticks like playdough. A part is buried in a half frame and sand packed around it. A top half of the mold is placed over it, and more sand is packed in. The two clam shell halves are separated, the part is removed, and a pour port is installed. The cavity is then normally filled with molten metal, but we might be able to do the same with epoxy.
It is also worth noting that pointman9 has demonstrated on another forum that castings can also work using normal epoxy as the casting material (he was using SgNerfs method) for non stressed parts like barrel spacers can work beautifully. It doesn't have to be devcon liquid metal.
Plastic epoxy or urethane resin is probably better for casting than things similar to JB Weld. You're not looking for total bond strength but rather tensile/yield/elasticity and impact resistance.
High strength epoxy on the other hand ends up being rather brittle.
Well, I'm thinking you are probably right. I was cleaning the hand cannon catch by clipping off a goober that was hanging out in the elbow, and when I made the cut the entire arm came off and the goober stayed put. I epoxied it back together and threw it back in the mold thinking it wasn't fully cured - even though a full 24 hours had passed. I haven't been able to get back to it yet, but plastic steel might be too brittle to cast parts from.
This builds upon work done by SgNerf on NH: http://nerfhaven.com...=1
With out his ground breaking work and discoveries this certainly wouldn't be possible.
Yes this mod involves oogoo (silicone caulk thinned with mineral spirits and corn starch). Do not get scared or intimidated by this mod. Start by asking a simple question: “Can I make Mac N' Cheese?” Mac N' cheese has 4 basic steps:
Boil noodles, Drain noodles, Melt and combine ingredients, combine cheese sauce with noodles. Making an Oogoo mold has 4 steps – no heat required! Mix oogoo, coat part in oogoo, place coated part in tub full of oogoo and once cured slice part out of oogoo! Wow you have a mold! If you posses the mental and physical capacity to make Mac N' cheese over a stove top, you should be able to do this too. It just stinks a little more than Mac N' cheese...
Changes from the SgNerf method: A cheaper and widely available mold medium is used. The part is entirely coated in the mold medium, and placed in a small tub – slightly larger than the part. The part is then sliced out and the mold separated. The result is that the entire part is duplicated – not just one side – opening the door to casting dimensionally complex parts – like a lanard hand cannon catch:
Here's what will be needed:
Silicone caulk (not ge II) the super cheap opaque $3 tube with black lettering from walmart works beautifully!
Corn starch (baking aisle at your local grocery store)
Silicone spray lubracant (mold release agent)
Mold containers (plastic baby food tubs work very well for small parts) large enough for the piece being duplicated to lay flat in (you'll be nearly filling it with oogoo, so a huge tub for a small part will waste a lot of material)
Gallon sized plastic bags (optional)
stirring sticks (popsicle sticks are suggested)
Sharp knife (to slice the mold around the part)
Devcon plastic steel two part epoxy (acehardwareoutlet via amazon.com gave me the best deal on shipping. I got (3) 2 oz sets for about $12 shipped.
Mold dead space filler (air soft pellets, washers, pennys... anything that you can fill the top of your tub to press the mold halves together while your epoxy cures.)
Yeah, you might be able to use RTV silicone, but seriously it's probably a lot thicker and is certainly more expensive... $10 spent on a tube of caulk and a pint of mineral spirits from walmart (liberate the corn starch from your mom's pantry) would give you enough material for at least 6 baby food tub molds with enough mineral spirits left over for another dozen molds.
Parts to cast...
I've selected breakage and wear prone parts: BBBB trigger, marshmallow xbow catch, and a lanard hand cannon catch. The bbbb trigger and xbow catch are pretty simple, and could of worked with SgNerfs original method, but the hand cannon catch is pretty complex and wouldn't of worked.
Make sure you have your parts before you start mixing oogoo.
You can either mix it in a plastic bag, or stir everything together in the mold container. The plastic bag will contain the stench of the silicone, but the container is a little easier to mix in and it will be easier to avoid making too much oogoo. Begin by squeezing out enough caulk to fill enough of your mold to cover your part. You can either use the plastic bag, or the mold container. I actually found it easier to mix in the mold container, but I had a pretty severe cold that day and couldn't smell a thing. Shake your mineral spirits up a bit (make sure the cap is secure) and pour in about half as much mineral spirits as you have caulk and mix the two together. The mineral spirits will thin out your caulk so it can penetrate smaller crevices release air bubbles and produce a higher quality cast. You want the consistency to be a little thicker than honey. Add more mineral spirits as needed.
Once mixed add a slightly rounded table spoon (small baby food tub sized mold) or two (for a bigger mold) of corn starch and mix that in too. Corn starch speeds the cure time from weeks to over night. If you've mixed in a plastic bag, cut the tip off the bag and squeeze the contents into your mold container.
Mixing in the tub:
Mixing in the bag:
Molding the part:
Spray your part with silicone (don't hose it, just give it enough to make it shiny), and shake it off. Coat it in oogoo, try to get oogoo in all the small crevices, and bury it in your mold container. Try to bury it so it's resting level, and either near the top or bottom of the mold. You'll need to have a pretty good idea of where it is when you go to chop it out. You can have a second part in the mold so long as they aren't touching. I cast the BBBB trigger in the bottom of a tub, and marshmallow x bow trigger at the top. Might as well make your mold multi-task.
Part in tub:
Hello little marshmallow xbow catch!
Put the lid on and let it cure for at least 12 hours or until firm and solid. Remove it from the mold, and set it aside to de-stink for another 3-4 days.
When I pulled the marshmallow xbow catch from it's tub I noticed an air pocket exposing the part. I mixed a little more oogoo, patched up the pocket and put it back in the tub. Long story short, you can repair your mold as needed.
Once you can handle your mold, grab a sharp knife, poke and squeeze the mold until you have a good idea of the parts location, and plan your cut. You want to make ONE cut all the way around the part so that you can pull the two halves apart like a clam shell. Carefully slice until the halves separate and the part is free. Yea! This should be a slow surgical process. You have a negative of the part trapped in the mold! If there are any large air bubbles open in the mold, patch with oogoo, replace the part and let it cure again.
Lets cast a part:
Spray a rag with silicone spray and wipe down your mold.
Mix enough plastic steel to fill the mold. Wow that stuff is thick! (you can always mix more if needed, the cure time is reasonably forgiving) and smear the plastic steel into the bottom half of the mold. Fill it till it's level, and place it in the mold container. Next fill the top half of the mold and place the top half on the bottom half inside your mold. Make sure you orientate both halves correctly! You need to apply even pressure from the top of the mold. I'm still figuring this part out, and right now I'm thinking the best way is to fill the dead space with something like airsoft pellets and put the lid on. Lacking air soft pellets, I used pennys. Washers may also work, but I think airsoft pellets would work best – being both small and spherical. Sorry I don't have a picture of that. Just imagine a tub partially filled with cured oogoo, with the rest of the tub filled to the brim with what ever small randomness you can come up with. Placing the lid on the tub compresses the randomness which presses the mold halves together while the epoxy cures.
Let the part cure overnight, (or at least 6 hours) remove it and inspect for defects. If there are any bubbles, mix more liquid plastic, fill the gaps, and return the part to the mold. Once fully cured (24 hours), remove, reinspect and trim any excess. Drill any mechanical holes needed, and install. I'm shipping the hand cannon catch off to TaerKitty for testing and evaluation. I don't use my hand cannon much, might as well have have it put through the wringer by someone who does. So don't ask me how durable the end product is yet. I don't know. I expect that they'll wear much better than the standard stock ABS plastic parts, but that is yet to be proven. Right now it's only proven that they can be made.
I'm also very interested in seeing what anyone else has cast. I would consider it on topic so, feel free to post pictures of your work here also.
A write up explaining magstrike piston theory was done by "Gas Mask Guy" and can be found here:
Magstrike Firing Mechanism Autopsy
With 3.5 squeezes out of a caulk gun, and roughly 2-2.5 spoonfuls of corn starch, I was able to make about 45 darts. There was a lot of waste since not every mold hole got filled. I'll have to do a better job at that in the future.
You said "Have you tried using GE Silicone I?"
Does this mean that you've been using it? If so, I don't have to worry about using my Walmart tubes conservatively, since when I'm out (of my 3 tubes I bought), I can just use GE I.
Shmmee- Those heads look fantastic! I love how neat the uppermost felt looks!
My latest batch used 2 spoon fulls corn starch to 3 squeezes caulk. They came out much softer than my previous batch. Darksircam suggested a volume based ratio of as little of 10:1. Your ratio might be a little rich. They look great though!
Just to avoid frustrations, Ge II silicone is listed on the oogoo instructables thread as one of the silicons that won't cure faster with the addition of corn starch. It's one of the caulks that cures by releasing moisture instead of absorbing it.
Based off a 10.1 oz tube of GE II weighing 0.8417 lb, a 3/8" diameter, 1/4" deep head would be 1.544g.
The weight calculation should be pretty close by volume between brands. Thanks for figuring that out.
To those well versed in steffan weights - would 1.544g be too heavy, too light, or just about right? I haven't started drilling on the next form yet, so it would probably be good to know if I should carry on as planned.
Edit: Wut. My felt tore, leaving a thin layer of fibers on the dart base. I stuck it back on. If I put felt on both sides and rip it off one, I can then glue it on the torn side. The intact side acts as the tip padding, as there's no leverage to make it tear.
That's awesome! It's great to see more people experimenting with this concept! Could you post a pic of your padded tips?
Of a curiosity, do you have any idea how thick your felt is? It seems to me that the higher ration of corn starch, the stronger the felt bond, the more resistant to tearing off, but the harder the head is. The felt I've used is propapbly the thinnest cheapest felt available. (craft store) It's just pure speculation, but because there is less material between the two bonds (head/felt bond and FBR/felt bond) they may bond to more common fibers, and result in less propensity to separate. Heads separating from the felt is new news to and I'm certainly not saying it isn't possible, but if it was filming up before you could finish getting the felt on, that might explain the failed bond.
While I still haven't been able to do any measured range testing, I did have a chance to do some serious war testing. Of all the darts I was able to find after the war, not a single one showed even beginning signs of failure. Some were glued to the fbr with hot glue, some with goop. The hot glue ones were much faster to build, but that's just because of the quick set time of hot glue.
They did hurt less than hot glue domes, and it was agreed that gumdrop heads would be an acceptable dart head material for future wars. (We eventually agreed to get away from domes, due to the ouch factor.) Hopper tests (with out any felt on the tip) was a substantial failure. It would only fire every other shot- the first shot serving to prime the dart into position. That's a problem that will need to be corrected if these are going to receive any widespread acceptance. My barrel fit/length may of been a little off as well. I forgot to shorten it due to volume loss added by the hopper.
I spent most of the wars shooting them out of my barrel replaced (just a basic insert done - for now! hee, hee, hee.) big salvo. Wow, I love that gun. My last batch could stand to be a little heavier - based on flight characteristics displayed, and as previously discussed - could use a larger surface area to absorb impact. The salvo and I (with gumdrop head darts) did well over all, getting more than our share of hits during the war. The slc nerf scene is definitely picking up!
Keep up the experimenting. I really do like to see pics of this concept, as well as successes and especially failures being documented.
It was about 10:1 silicone to cornstarch. I have yet to actually test the density of caulking silicone, but all of the web resources say that most silicone rubbers have a density between 0.9 and 1.2g/cm^3. With an estimated density of 1.0g/cm^3 and an estimated tip diameter of 1.0cm, you should be using molds that are about 10~11mm deep to meet the current specifications for slugs and APOC standards. So how deep are your molds? I expect something like 1/2" or so, correct? If you drop a felt disc at the bottom and use another on top, they should be perfect. Except for, you know, being 1/2 an inch longer than your other darts.
Actually my most recent darts are about 3/8" deep + felt. My next generation (clylinders) will be 1/4" deep, but hopefully a little wider (a full 3/8" wide) to increase surface area. I don't think I've done any that come close to a full 1/2" deep. How have they worked for you? I don't know if you've had a chance to try the felt backing yet, but have you had any trouble keeping them glued on?
I'll try your 10:1 ratio of corn starch with a felt tip on my next batch. (As soon as I get the next form set up.)
It seems like they are a lot more time consuming to make, and you say the impact force is similar to that of a hot glue dome. I guess my question is, what is the major benefit of these dart heads over other contemporary dart smithing methods? I'm not being sarcastic or snide here. People seem genuinely excited about this, and I'm just wondering what this new method offers in terms of improvements.
That's a fair enough question. I really would be shocked if any new unproven technology is greeted arms wide open without scrutiny.
-No Mcmaster order (or shipping costs). All materials are waiting for purchase at your local hardware store, and craft store (felt)
-No metal weight of any kind. when a slug head separates mid flight, you have a projectile that's half felt pad, half metal washer with the potential to cut someone.
-Consistency - as long as your form is consistent, and your fill is complete, each head is identical in size, shape, and weight.
-Durability - Felt is a more porous bonding surface than metal, and is more likely to withstand abuse.
-Range - I've seen a 25' increase in previous batches compared to slugs. (I do realize there slugs are often required because of their limited range to improve game play)
- Accuracy - this has yet to be verified, but it seems logical that a heavier dart head would fly in a straighter line.
-Repeatability - Even a new dart maker with a form can produce consistent results equal to a seasoned dart smith.(which increases the overall safety and quality of darts on the field.)
-Customization- Add oil based dyes during mixture, couple with the dozens of different colors of felt, and make darts that are recognizably your own.
Cons: (yes, for the benefit and perpetuation of this discussion I'm also listing problems that I've seen. That way we might get more suggestions in, and either accept the limitations, or fix them.)
-A form is required Sure, you can make one yourself, but that's time that could be spent doing something else.
-More time and effort compared to slugs. 'Nuff said there.
-Currently lacking padding on the tips.
-Their isn't a glue on the planet that bonds extremely well with the silicone. (Trust me, I've tried close to a dozen!)Adding the felt backing was a last ditch effort to give us some way to glue finished heads onto dart blanks. Any glue bonds to felt! (The oogoo instructables website claims that fresh oogoo will bond to cured oogoo. Since oogoo bonds to felt and porous fabrics, we may be able to use oogoo to glue felt padded discs on after they've cured.
- Hurts like a hot glue dome. This needs further development, but isn't integral to the basic performance of the darts.
Increased range - this is included in both lists, because not everyone will view bigger ranges as a good thing.
- Poor hopper performance - Roughly 1 shot of 6 failed to fire on the first shot. That's a big issue. We'll need to pad the tips some how, even if only to reduce friction.
Sorry Just some Bob, Had my wife shoot me from 10' away with my pas (with added ls spring, 12" straight barrel, no hopper.) and one of the lighter pointy tipped darts. I definitely knew when I got hit. Though that was close range and a high powered blaster. I'm sure a slug would of also hurt under those circumstances. At the very least it was nothing like getting hit with a stock dart shot from a near stock blaster. The outcome might be different with a lower powered blaster, or normal ranges.
Anyone who shoots someone else from that close with any homemade dart and mid/high powered blster is going to leave the victim with a welt, and probably be labeled a douch. I just have high standards for these things, and think the pain factor can be reduced by the addition of padding. The increased surface area of the flat head darts may also help substantially. I just haven't made any of those in the felt backed edition.
A homemade, consistent, metal free, mass producible dart head made from materials readily available at almost any hardware and craft store!
It uses a home made mix called "oogoo" as the main dart head material (silicone caulk + corn starch to shorten cure time). http://www.instructa...gru-Substitute/ Read it, it's great.
With recent advances made, I feel confident enough to present this as a completed and functional product. The bond of the head to the felt backing is nigh inseparable! I pulled with my fingers, and gave up. I pulled with pliers, and the head tore in half before separating from the felt!
Credits: Thanks to Darth Maker for the discovery of oogoo, Taerkitty for thinking up the felt backing, and Just some Bob for coming up with the gumdrop name. Also thanks to those who helped with other ideas, and encouragements while this concept was being developed. This has truly been a group effort, without the nerfing community (special thanks to Nerfrevolution.com, where this was developed), it would never of gotten off the ground.
The format of this write up will be a written format, supported with video of the process. That way everyone can see just how incredibly easy these things are to make.
For pointy heads - a polyethylene (white plastic) cutting board of any thickness greater than 1/4".
For flat heads - 3/8 - 1/4" white plastic cutting board (2)
counter sink: "four cutter cutting bit" ((It's a counter sink with an adsustable center bit - sold at any hardware store)#10, or #12- though #12 heads have been known to jam a hopper - but that could of been a pre-felt separation issue. I'll have to re-visit #12's the increased surface area might help decrease pain.)
3M window and door silicone caulk (or any other clear silicone caulk with a ton of warning labels on the back. NOT GE II silicone. It cures by releasing moisture instead of absorbing it.) It should reek of vinegar while curing.
Ziploc bags (to mix in) Gallon size for batches larger than 100 heads
square of felt large enough to cover your dart form.
Mineral spirits (optional - softens the final product)
A work space you can temporarily stink up.
Drill press or drill with masking tape to mark a depth/ stop drilling ring
Wood paint stir sticks
scrap sacrificial board - opt. (to make a flat head form put it under your cutting board as you drill, any flat drillable material will work)
clamps/screws - opt. (helpful)
3/4" (or larger) scrap of PVC to use as a roller, longer scrap of cpvc to slide in and use as an axle.
Packing tape (or other) to tape your mixing bag to the table to hold it in place while you mix.
#10 (.375") or #12 (.425") "four cutter counter sink (For pointy head darts)(or a normal 3/8" or 7/16" drill bit - for less pointy heads) to drill your form with.
Uni-bit to pilot drill your form holes (for flat holes) (optional) They stay centered better, so you can space your holes closer together.
Materials Video: (click to open in new window and view. Not sure how to embed video. Feel free to PM me with pointers. Also, wow I hope I really don't sound like that. I sound like frekin' Kermit the frog.)
Form making basics
The majority of time spent on this project will be invested in making your form, but it's infinitely re-usable, so no big loss! Spend the necessary time to lay it out well, and do it up right.
Space your holes as close as you dare to drill if you plan on separating the heads with scissors, about 1/8" apart if you plan to separate them using a punch. Use the width of your counter sink as a guide. I laid the flat tip of mine on the edge of my board and traced around it with a permanent marker, then drew lines coming off of the point with a framing square. Try to line your holes up in straight lines so you have the option to cut them apart with scissors if needed. Off centering every other line will fit more dart heads on the mold, but it will add time to cutting them out. Leave at least a 1/2" border unrolled around the outside of your form.
To make a pointy head form: (Easiest, but not by much)
Set the depth of the internal shiny drill bit in the counter sink so it's barely poking above the black part of the bit (adjustable via hex screw). Chuck it up in your drill press / drill. Set your depth to 1/4" below the surface of the cutting board. (Less if you want shorter heads, more if you want taller heads). Drill out your heads. This plastic drills very easily and cleanly, but it did leave some scraps clinging around the center hole, so go back through and check to make sure their aren't any small pieces left behind.
To make a semi-flat head form:
Use some fine bolts (or even spare nerf gun screws) to join your cutting board to your sacrificial board. The sacrificial board will keep the edges on your exit holes clean and level.
Adjust the depth of the drill bit to to drill partially through your cutting board and into your sacrificial board. The size of the exit hole in the cutting board will be the diameter of the flat spot on your head. Your heads will be as tall as your cutting board is thick, so be picky when you buy your board.
Use a "four cutting" counter sink to drill your holes partially through your cutting board, and into your sacrificial board.
Credit for the backer board goes to Taerkitty and originally K9 for suggesting drilling through and using a backer board to take off the point.
To make a flat head board (cylinder):
Drill through your cutting board (1/4" to 3/8" thick board - board thickness defines head height) using a 3/8", or 7/16" bit (depending on how tight you want your tolerances, and how heavy you want them to be). Bolt another cutting board behind it.
To tip the cylinder heads in felt - prep felt discs by using a hollow punch and a hammer to pound through stacked layers of felt (I've gone through 6 at a time) separate the discs, and place one in the bottom of each hole. Gently separate the board from the backer (nothing holding the discs in place but friction), coat the back of the form in backing tape, re join the form and backer, then press the discs into the tape to hold them in place. (You'll have packing tape sandwiched between your form board, and backing board.)
(Currently developing similar method to tip them in dryer lint. - hopper feeding with out felt discs on the tips)
Squeeze silicone caulk into a Ziploc bag (use a name brand bag with the double strips of seals. It's a wasteful mess if the bag opens while mixing.) 6 complete squeezes from the caulk gun makes 175 3/8" tall heads. If you want to add mineral spirits, to soften the final product, or oil based paints to change the color, add it and mix it in now. I don't have an exact ratio of mineral spirits figured out here. I just added and mixed till it didn't feel quite so thick. Tape your baggie down to a table, and mix it back and forth with the roller.
We haven't added the corn starch yet, so no rush. Make sure you have every thing you need for the rest of the process close at hand, and your form is secured some how to the table. If you're making flat head darts, screw or bolt your drilled head form onto an undrilled piece of cutting board. (That will keep oogoo from shooting out the back) Once you add the corn starch, the clock starts ticking!
Add 1/2 spoon full of corn starch for every 1 squeeze of silicone into your bag. Squeeze out the air, and tape your bag down to your table, make sure it is sealed, and mix it together with a roller. The corn starch shortens the cure time of the silicone from 24-48 hours down to 2-4 hours!
I thought I took video of the mixing, but it didn't take. It's pretty self explanatory, I'm sure you can figure out how to mix two or 3 ingredients in a plastic bag.
Filling the head form
Video (again, click to open in new window and view):
Once mixed, roll every thing away from a corner, and lop off a large corner from the bag. Roll it back towards the corner, and squeeze the glob out onto the form.
Glob of Oogoo waiting to be pressed into the head forms. You can see the backer board clamped to the head form board in this pic it was just a small, trial sized board though. I would recommend bolting them together. (It should reek of vinegar. Open windows and such.)
Smear it into the divots with a paint stir stick, scrape off the excess.
Lay your felt over the board, and go over the top of it with a roller. Rub your thumb swiftly over the top of the felt. This will help work the uncured mixture into the fibers of the felt.
Allow to cure (should feel semi firm if poked). I have waited as little as 4 hours to remove them from the mold.
[I'll add a video of the dart heads coming out of the mold as soon as I can take it.]
Once cured Pull the felt off of the mold, and the heads will come with it! Separate the heads by either cutting them apart with a pair of scissors, or use a punch and hammer (harbor freight - $8)
Pointy (before we discovered felt backing):
And after we discovered felt backing:
Flat (before we discovered felt backing):
Cylindrical felt tipped heads:
[pic goes here once they're out of the mold]
Note: save your unused tube of caulk for later by cutting a corner off of a plastic bag, fill it with silicone, and hold it on with a rubber band.
Now glue the felt side to your fbr using your favorite glue and be done with them! [I'll update with a pic of some finished darts later]
Ranges: depend largely on the size of the dart produced. Previous (heavier versions) flat heads have out ranged my slugs by 25'. It's raining all week here in Utah, can't do range tests.
Hopper feeding: sucks.
We may want to work out some sort of padding/coating on the tip.
- feel free to throw out some suggestions!
(see slugs domes and other dart heads thread for development http://www.nerfrevol...t=2443&start=60, as well as the original counter sink dart heads thread: http://www.nerfrevol...&p=30679#p30679
[edit: added form description - cylindrical heads]
Mother F RIGHT! Nice work Mr. Schmii.
Now, on to the questions: Do these heads cause friction or sticking in a hopper clip or a Wye like the head of a streamline will? Or will they slide smooth like the felt head of a slug dart?
Previous versions (without the felt binding) had serious adhesion issues, and have come off while rounding the bend - jamming up mid barrel. These with the felt backing are much stronger! I'll hopper test them tonight. My hopper is a homemade one - a coupler welded to the back of a 45, and a pair of air holes through the 45. I left a center post in the middle of the wye to help guide darts around the bend (like a britt hopper), so it may not be an accurate performance baseline of a standard Wye. They don't have the stems that impair streamlines, so I expect they'll work well.
Shmmee, have you tried a brithop-type configuration with cpvc to see if that will make the darts feed through hoppers? I would think that that possibly coupled with Taerkitty's SlantHopper could get these to feed reliably in a hopper. My hopper is currently set up like this and it has almost never mis feeds, even with 2'' slugs.
My wye is actually a homemade. I took a coupler, miter cut one end at a 45, and plastic welded it to the back of a 45 elbow. I then dremmeled out two holes for air to pass through - leaving a guide post in the center. Instead of reaming out the cpvc and pvc it's nested into - I extended the cpvc beyond the pvc, reamed it to a knife edge, then heated and flared it out till it was touching the walls of the wye. In doing so - it does sit farther in than had I simply reamed the pvc, and cpvc. Perhaps the dart is impinging upon the flared cpvc before the tail has passed the bend.
It's performed well with slugs, and pom-pom tipped darts. I recently realized that my valve at the top of the feeder tube is not air tight. That could explain why the occasional dart would stop mid barrel. However the leaky valve wouldn't explain why the first shot is needed to prime the dart, and the second shot fires it (sometimes).
At the next available opportunity, I'll ream the cpvc and pvc to a more standard set up, and replace the feeder tube valve with a simple cap and see if those changes affect performance.
Awesome! Do they feed any better in hoppers with a felt tip?
I was just looking for something that would cover the head like Darth Maker said. Felt heads solve that problem anyway.
Precut felt heads, yes. I've yet to acquire a reliable method of punching holes. Especially with the thick felt. Ah well. For each dart I make, I peel off the felt on one side and use it for the tip of the next batch.
Four of the eight darts turned out well. Examples of the good and the bad. I experimented with just throwing felt pieces in as well - turned out very lumpy. The main problem here is that the felt doesn't STAY at the bottom - might leave some deadspace. You can also use thicker boards with this - I think I'll be getting some 1/2" thick boards for the final molds.
I tried making a pointy head for form/some darts for the first time last night, and it turned out a bit wacky. I drilled 1/4" into the board (just as the writeup said), using the DeWalt countersink bit (I like the pointy heads a bit better), and my sili heads came out looking nothing like how they looked in the OP. First of all, there was a small dimple between the drill hole made by the countersink and the drill bit itself (caused by the open area between the 3/16" drill bit and the countersink bit (since to adjust the drill bit's location, you have to move the countersink). Also, the heads looked MUCH shorter than those in the writeup (what depth, Shmee, did you use for those heads shown in the OP pics?)I'll try to post pics this afternoon.....
The exact height of my most recent pointy head batch is .280" (a hair past 1/4"), but that includes felt...
Here's a pic of how far out the counter sink bit is (again for pointy heads.)I noticed from the pic that one of the spiral grooves is jam packed full of debris. That made drilling slow, but I guess it also prevented uncut plastic from hiding in the gap.
I remember pre drilling the holes with the center bit extended to a depth of 1/8". With it barely sticking out like it is, it has the potential to slip till it finds it's groove.
Updated op with pic of most recent pointy head darts.
Everything is still curing in the forms, but here's what I've tried doing differently:
Increased diameter to 7/16" (1/4" tall), and a flat conical shape. (increases surface area, and mass)
Tipped the dart heads by dropping a felt disc down each individual head form prior to fill.
Bought a hollow punch set and a 1lb dead blow hammer (plastic hammer filled with pellets that transfer all of the energy into the object it's striking). Tried punching single felt discs out of felt (felt is substantially cheaper off of a bolt from a fabric store. I bought a full square yard for $2.39) It was difficult to punch through a single thickness of felt, but after folding it over into 6 layers, it punched well, with about 4 blows from the hammer. It also made 6 discs per 4-5 swings.
I placed a disc in each head form, but they shifted, and rode up the sides of the wall, so I coated the back of the form with packing tape, and stuck the discs to the tape in the bottom of the form. That solved the shifting, and kept them in place while filling.
Everything else was done as normal.
I'm concerned - due to the difficulty of punching through a single sheet - that it may be difficult to use the punch to separate the heads from the backer felt. I was using a scrap piece of maple floor board to pound on. Would some sort of softer material be more effective as a pounding board? Some sort of rubber, or a pine stump (facing the grain) or sacrificial layer of felt glued to the board help to make punching out discs and heads more effective?
I'll get pictures up when I can. Thanks all.
This is the first thought to strike my mind when trying to tip the gumdrop heads, but further thought of a mold with felt on top, felt on bottom, and cured oogoo - perma-bonded to both sides of felt cured in the middle - turning the mold into an oogoo sandwich steered me away from it. Individual pre-cut dots are probably the best way to go.
Another idea is to put a sheet of felt clamped in between the two boards, but then they would be harder to punch out, because you cannot put the head through the punch prior to punching through the felt.
Darts now feed well - no misfires, I've tested four times with a five-shot hopper.
These should be more durable than slugs as well - foam-felt attachment is more secure and less prone to breakage as the felt bends with impact.
That's great! Poor hopper feeding has been one of the big down sides to these things. Thanks for doing a fix for them!
Here's a thought for getting the felt to stay put while filling:
Use a mold with holes breaking the back surface (drilled fully or at least partially through) Peel off an Avery sticky label (of appropriate size) and stick it to the back of your form. You'll then have a sticky surface exposed at all holes. Stick a felt disc in the bottom (label should hold it in place) attach backer board, and fill as normal.
You should also be able to re-use the label by shifting it slightly to expose some fresh stickiness.
Drilled out some more holes and made another batch of about 30 darts.
Is everyone using a paint stir stick to poke the oogoo into the holes? I prefer using my fingers... or if possible, a plastic-coated wooden rod about the same diameter as the tip diameter. Makes sure you get the oogoo all the way in, and it's pretty quick. Then smear some more over and repeat.
The amount of cornstarch may also affect the smell... if it acts as a catalyst, more vinegar smell is generated, and it's generated faster.
Edit: On felt: You should be looking for felt that does NOT fall apart easily - fluffy felt makes bumpy/unbalanced dart heads.
Darksircam: Thanks for helping to keep this concept alive!
With a solid piece form I did have some difficulty getting the air pockets out, and the form filled, about 1 of 20 heads were defective because of that. With a 2 piece form - It's much easier because air can escape between the boards as oogoo is pushed in.
The instructables site suggests wrapping anything you want to use as a spatula in "Gorilla tape" (gorilla [same brand as gorilla glue]brand duct tape. Cured oogoo will peel off easily from that stuff.
My experiment of "outsourcing" dart production to my sister is going well. She's had a 1 or 2 batch learning curve (first batch the backing felt wasn't pressed into the oogoo enough, so there was a poor bond to the felt), But I'm now confidant that anyone with a form and the patience can make these.
I've slapped a PTEG'd 7.5" RF20 turret onto a big salvo. I don't know what ranges are compared to slugs, but the 20 shots I took (minus the few from a belligerent tank) averaged 75'. The max was 99, min was 54'. That is a pretty big spread, not sure why, though I suspect turret seal issues. I don't know how slugs would compare, but I'm at least hitting war worthy ranges with these darts.