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Introduction: The lost art of capacitors in airsoft The mythical powers of "capacitor banks" is not a new idea in airsoft, but the original sources and theories are lost in time, with only faint forum posts remain (all the links are dead in https://www.airsoftsniperforum.com/threads/capacitor-banks-revisited.8688/). In my pursuit of the ultimate trigger response in AEG, power supply remains a big unresolved issue because batteries (LiPo or NiMH) do not really give enough oomph for lack of a better word. We need something better, I thought, we need supercapacitors. And so I set out to rediscover the elementals of such dark magic from scratch (but based on the same principles). And I believe I have revived this magic which I will share my formula below. And dare I say, the surface of this dark art has not really been scratched, because the predecessors either did not use enough capacity (some examples were in the order of millifarads which is not nearly enough), and did not really use the correct type of supercaps (stacked coin cells hybrid types are not capable of high amps). And perhaps the right modules were not available until very recently, so this study will also represent a fresh look into this subject. If you want the bottom line: Why supercaps at all, isn't LiPo good enough? In short (excuse the pun), LiPo cannot provide sufficient peak current for the amp spikes during start of motor which is often in the region of 45-60 A. These micro-events of shorts (from the perspective of the battery) is also a main pathology of LiPo degrading and swelling over time. These spikes happen every shot in semi, and in the first shots in full-auto. This status quo practice of relying on abusing LiPo as sacrifice for performance does not sit well with me, because firstly it is electrically primitive, and secondly it is a safety risk in this toy gun industry that I think is unnecessary and should be done away with, at least as much as possible. The whole premise of using supercaps is to provide a voltage reservoir for surge power during these initial amp spikes. This is needed because these amp spike often exceed the capabilities of the battery (even LiPo) and the batteries drops voltage in response (for milliseconds) and unable to feed all the current needed for this initial spin-up of the motor. In theory, it can achieve the following: Surge power for much more responsive motor, resulting in snappier trigger response. Stabilised voltage supply for full-auto, resulting in better ROF. Protecting batteries from surge currents, prolonging their lifespan and minimise risks of LiPo fire. My evidence and theorisations are as follows. What is the actual energy requirement? To begin to figure out the solution, we need to ask, what is the minimum capacity to be effective? We can analyse these two graphs from airsoftlab.eu for theorycrafting. http://www.airsoftlab.eu/docs/experiments/motor_current/ To figure out the ballpark of energy levels we are talking about, I have picked two cases representative of a high stress build (with a 16 TPA motor) and a more optimal build (with a 28 TPA). The first graph is with 16 TPA motor, SP130, 13:1, to illustrate a typical suboptimal setup with a low torque motor paired with a high stress spring and gear ratio. The second graph is with a more comfortable 28 TPA motor with SP130 and 13:1 to show a more efficient setup. Just by eyeballing the graphs (and the blog), we can character these spikes (and the energy required to tame them) to be about 45A to 60A, for a duration of about 60ms. 16 TPA: 28 TPA: What do the numbers mean? There is a simple answer, and a more complex one. A simplistic way to translate this to farad (the capacity we need), using the 16 TPA setup as example, 60A for 60ms is 3.6 coulomb, which at 11.1V is about 0.324 F. For the 28 TPA example, this would be 2.7 coulomb, at 11.1 V this is 0.243 F. Therefore we can say our ballpark figure is about 0.25 F to 0.33 F as a minimum target. If we are aiming to create a unit that can work with worst case scenario, let's go with 0.33 F. However because supercaps discharge their voltage linearly (meaning their 11.1 V drops down to zero as it discharges over the 60 ms), we can think of it as sharing the workload with the battery in a 1:1 ratio (this is very simplified), meaning it is only doing half of the work while the batteries still need to supply the other half of the current (which is a big improvement already). Here is a prediction: In this predicted scenario, the amp spike seen by the battery should be reduced to less than half, because the supercaps will react faster to supply the spike, but as the supercap runs out of voltage, the battery will notice the difference in voltage and catch up, eventually supplying the full load in full-auto, but at a much improved stability. And as the trigger is released, the current stops, the supercaps are charged up again to battery voltage as the battery recovers from voltage sag. We can offload even more work from the batteries if we multiply the supercap capacity (say 3 times, to 1 F) so the they will perform in a 3:1 relationship i.e. 75% of the work are done by supercaps, which will stabilise the current even more. If we go bigger, say 1.66 F, the ratio will be 5:1, or 83% of work being done by supercaps. (The actual result will probably be better, the ratios e.g. 1:1 at 0.33 F are just conservative notional numbers I made up for ease of explanation. Supercaps are more responsive than batteries, and the overall lowered battery stress should further reduce overall voltage sag, so the battery should see less than 50% of the peak current, but I don't have the equipments to proof this hypothesis.) So let's say our notional baseline is 0.33 F, now we just need to implement this theory. Designing a supercaps unit Here is our goal: 1. Supercaps with total capacity of 0.33 F or more, bigger the better. 2. Voltage should be ok for airsoft usage. (Say a fully charged 11.1 V LiPo is around 12.6 V) 3. Overall size to be small enough to fit in a typical buffer tube, with room for cable management for most cases. Smaller the better. 4. (Bonus feature) built-in safety to drain residue voltage when unplugged. 5. (Bonus feature) LED to indicate presence of voltage. The obvious (and probably the only viable) strategy is to use 3 no. of 5-6 V supercaps in series to give us a 15-18 V headroom for the maximum 12.6 V we are expecting from a fully charged 11.1. The first problem is selection of supercaps. The second problem is designing the whole package that can physically fit inside the buffer tube. Long story short, here is my blueprint: (Just connect the supercaps in series, and then parallel with the batteries, I don't have a drawing) The Eaton supercaps I am using are the highest capacity that can still fit inside a typical buffer tube and wiring, and with one of the better ESR in its class, and can theoretically suffer 115 A of thermals over 60 ms, and tested to MIL-STD 202G for shock and vibration. They are wired (I'm using some fancy SPEC 44 16 awg wires) to a connector that goes between the AEG wire and battery wire, so it is completely plug and play, and removable for safety and for storage. It can in fact be stacked up (if you have multiple units) to give extra performance. For extra safety I have included a bleeder resistor to discharge the residue voltage in maximum 3 hours after it is unplugged. Also for safety (and aesthetics) I added an LED for visual indication of voltage presence. I am tempted to call it the PASTA 1000 (Pseudotectonic Advanced SupercapaciTor Array 1000 mF) but any suggestions welcome. Here is what it looks like in real life: Testing AEG: Specna E-19, completely stock (which has an X-ASR mosfet preinstalled.) Battery: 9.6 V NiMH, fully charged, measuring about 11.32 V when testing. This is just a simple A/B test to see if the supercaps work at all. I will simply alternate between plugging and unplugging the supercaps several times, then take measurements with groups of 6 to 7 shots, until the data are fairly consistent and/or a pattern can be identified. The groups are measured in Audacity and averaged and rounded to nearest millisecond. Also note I am not testing with any magazine inserted because A. that is not going to make massive difference either way and B. it is one less variable to worry about and C. if a BB goes off it is going to affect my measurements with sound. The results: Stock setup (without supercaps), group #1: Trigger response: from trigger action = 83 ms, from motor spin-up = [data missing] ROF: ~17.17 RPS With supercaps, group #1: Trigger response: from trigger action = 81 ms, from motor spin-up = 57 ms ROF: ~17.48 RPS (+1.8%) Stock #2: (I stopped measuring full-auto because it is getting too loud for the neighbours) Trigger response: from trigger action = 96 ms, from motor spin-up = 64 ms With supercaps #2: Trigger response: from trigger action = 74 ms (-23%), from motor spin-up = 62 ms (-3%) Stock #3: Trigger response: from trigger action = 90 ms (+22%), from motor spin-up = 69 ms (+11%) With supercaps #3: Trigger reponse from trigger action = 71 ms (-21%), from motor spin-up = 62 ms (-10%) Stock #4: Trigger response: from trigger action = 84 ms (+18%), from motor spin-up = 68 ms (+10%) With supercaps #4: Trigger response: from trigger action = 76 ms (-10%), from motor spin-up = 62 ms (-9%) Stock #5: Trigger response: from trigger action = 80 ms (+5%), from motor spin-up = 69 ms (+11%) With supercaps #5: Trigger response: from trigger action = 75 ms (-6%), from motor spin-up = 61 ms (-12%) Analysis of results: Definitely a noticeable audio difference in trigger response. The only way to describe it is it sounds more "instant" and there is less of the spin-up whine. I am not sure why the groups vary quite a bit (maybe battery and/or gearbox settling) but I think it is fair to say the supercaps are making a difference. If we average the data after group #3, with supercaps, the overall trigger response is about 14% improved, with the cycling time from motor spin-up is remarkably consistent at about 11% improved. The shorter lag time from trigger action to motor spin-up can be explained by the voltage stability provided by the supercaps. Overall I didn't know what to expect but I would say 14% improved trigger response is pretty good. It is definitely not a negligible difference, and definitely noticeable when compared side by side. But going by feel alone, it definitely feels a bit more snappy. ROF is probably improved a little bit, but more testing needed. The installation: This may be the only draw back. To actually fit the unit inside the buffer tube along with the X-ASR is a massive hassle, which I have to actually remove the original long heat shrink around the three wires to get them to flex, and re-crimp two out of three of the spade connectors to the X-ASR because they were damaged by too much bending. And even when the supercaps are in, it is still very stuck and you need to wrestle the wires to get the battery on and close the butt plate. Although I have done it with the stock fully collapsed and if I install it with the stock a few positions out, it will be easy. Once it's on, it works. But it is definitely not ideal if you have any in-line mosfet like mine. However if you use a proper mosfet inside the gearbox and just have wires in the buffer tube, it should fit very easily, potentially upping the supercaps to 5 F ones for even better trigger response. There is no noticeable sparks or heat or anything when install and in use. It simply lights up when you plug it in and it just works with zero drama. Here is how it looks like installed, with a fully collapsed stock, and without the stock: (it barely fits) To uninstall: If the battery is disconnected with just the supercaps plugged into the gun, the gun will barely able to do one shot and the second shot will be stopped by the mosfet because the voltage will have dropped too low. This is just as expected and fairly consistent with the maths. The LED: When you unplug everything, the LED stays on but slowly dims down over the course of about an hour (just as designed). This shows the draining resistor and the LED are all working as intended. I could also feel zero heat from the resistor, which is great and again matching expectation. The LED still visibly faintly glows even at as low as 2 V so it works perfectly for its purpose as a voltage indicator. The red LED is pretty to look at, although I might change the colour to something like blue or green, because the red can be mistaken as error from the mosfet. I might also move it to the "top" side of the "plug". Conclusion of experiment: The prove of concept is a success. Most importantly there is certainly a performance benefit (14% in my test). All the maths check out. The unit is fully functional and fully match the expectations. It literally is plug-and-play. The installation can be a hassle for wire management but that is purely down to physical space and should not be a problem if you are not using in-line mosfet. Conclusions and speculations More testing is needed with other setups, if you would like one for testing I can make you a copy for a fee. The tech tree can potentially branch into AKs or other platforms or even external compartments, but I don't have any of these for development. Here is a summary of what this device can do. The biggest feature for me is safety, because when the LiPo (or any battery) is shielded from stress they are much less likely to puff up over time and starting a fire. Another key thing is of course the performance. It works very well in my very first little experiment. Electrically the overall voltage floor and current ceiling is improved. Adding supercaps is a bit like transitioning from NiMH to LiPo, but on steroids. There is also where the drawbacks are, because a mosfet is probably a good idea for such power, and if you want to collapse the butt stock you will need a more advanced mosfet that sits inside the gearbox rather than the buffer tube, for cable management reasons. (If you copy what I did you will risk breaking some wires) In terms of use cases, it will benefit NiMH the most because the performance is suddenly brought closer to that of LiPo because the performance gap is effectively closed, making NiMH a viable option again. In fact it makes NiMH better than LiPo because NiMH is much safer. This is also a must if you are chasing the state-of-the-art trigger response or battery efficiency in any build. It will also help with cold weather performance. And the best thing is, this is essentially a "free upgrade" because it is an entirely new component added to the system, it does not replace or compete with any existing parts, and it doesn't need any complicated installation, it is literally plug-and-play. The only downside for now is with wire management inside the buffer tube to make room for it. I am not sure if there is enough space for guns other than an M4 but maybe you can find creative ways to fit it e.g. longer wires. This can potentially benefit rental fleets because it is the easiest upgrade possible with zero overhead on tech, plus it makes your NiMH or LiPo inventory much safer and longer lasting. The savings in overhead for battery management could be worth the investment. And when a gun dies you can very easily transplant it to the replacement gun. In theory, you can actually stack multiple units for extra performance (the only problem is finding the space to put them). Conclusion is, and I am probably biased, supercaps could be the next best thing in airsoft. If the space problem can be resolved. Please do comment if you spot any issues in the theory or in the blueprint. Thank you for reading.

Welcome back. You won't know until you've shot it a bit, but I wouldn't be paying a generic "tech" to do generic tasks. Some specific individuals are good at some specific tasks, but you'll be paying £40+ an hour, so you'll to want to be sure that it's needed. Lithium batteries tend to survive well with some charge in them, so I wouldn't fret about them either, I'd just charge them in an Explosion Containment Pie Dish the first time and keep an eye (and a hand) on them. If you're in any doubts about getting through the day, a new battery wouldn't be a crazy expense. I'd bin any bio BBs that you have, magdump the .25g, and agree with going up to 0.28g if your hop can lift them. The spring might have weakened, it depends how compressed it was. There's only one way to find out. Airseal is what would concern me, and only to the extent of pulling the thing apart and putting a small squirt of silicone spray (or oil) into the nozzle and letting it soak into the piston o-rings for a while, then doing some bursts of auto fire until it's blowing entirely clear before re-assembling. Check the hop rubber for stiffening or cracking while you've got it apart. Maple Leaf rubbers (and Omega nubs, or the SHS equivalent) perform pretty well in most guns. https://ak2m4.co.uk would be our go-to recommendation for any parts that you need.

Don't save money by buying new, buy secondhand & pay double🤣 He's got a damaged pistol that's an absolute bargain too😏

I got the same response. Given the week she's just had, I predict a possible change of heart though...

I ended a long term relationship today......I'm not too bothered,it wasn't mine.

Rental guns generally have hard lives, but don't expect an OMGAMAZEBALLZ performance increase with an entry level gun. Slighty better - probably? The key difference having your own gun would be the fact that you can upgrade as time goes on. From what I've seen of the Flex guns (I've had hands-on at the Z1 showroom a few months ago) - they would make a lightweight and nimble platform for some modest upgrades (i.e. motor and hop rubber/nub) at a reasonable cost. Internally, they are the same as the CORE series. In fact - Fire-Support are flogging them for £90 here - which is the cheapest I've found: https://www.fire-support.co.uk/product/specna-arms-sa-f01-flex-aeg-carbine-replica-black

It's not a license 🤯

The spring might well be weakened if it has been compressed for the duration, for example if the piston was not fully forward. What do you want a tech to do? Most airsoft guns are reasonably easy to service provided that you take it slowly, photograph everything as you take it apart and watch lots of disassembly videos for your gun online. What gun is it? If the 0.25s look ok, use them to chrono the gun (if you have a chrono) to see what power it is doing; this will help you to work out what, if any, work needs to be done. Rogerborg's suggestion of spraying a bit of silicone into the air nozzle to regenerate the piston head O ring is a good one.

When your gun doesn't sell for the same as retail price most people would reduce the price. Not this guy, he relisted it for £20 more

Named my Christmas tree Amy Winehouse this year. Well, it's going to die and leave needles all over the place...

My Mrs once asked me what I wanted to do for Christmas. Unfortunately fuck off into the woods camping for a week wasn't the answer she was looking for

What did the farmer say when he couldn't find his tractor? "Wheres my tractor?!" 🚜

Today I qualified for a UKARA licence and am going to buy our first guns. I say ‘ours’ as my 12 year old son and myself are taking up this hobby. I’ve been doing my research and think I’ve settled on the Specna Arms Flex series. These seem like good value for money and are very lightweight which I think is good for my son. I have to really think of the budget as I’m buying x2 of everything including face protection, spare mags, etc. Do you think this will be enough of an upgrade from the standard G36 rental guns? Anything else I should be considering? Thanks guys.

Read the title Thought it was one of the recent spammy witch doctor cnuts at it again 😂

Awesome. 👍 I knew those years studying electronics wouldn't be a waste. I'm a bit rusty but the theory stacks up ok in my head. I'll read it again when I'm awake a bit more tomorrow.

Not bought anything of substance from them, but I've been in their shop and the guy was very friendly, the range they had was pretty awesome and their prices seemed reasonable. I'd buy from them

Hello, goodbye.

Cheers for the heads up Tackle, I’ll keep a look out for the pedants 🧐. When you’re a noob it easy to press the triggers 😂 Speedbird_666 that’s great information, the Flex is seriously cheap on that site, anyone bought from them before? You’ve got me thinking though, should I up my sons budget and get him something better? I don’t mind waiting for a bit longer to get my gun. What I don’t want to do is spend 100’s on guns now and then want to update in the summer. I know this always happens with a new hobby but if I can limit it now…..

I've taken pity on the chap and told him what he should actually be asking. I await the "I noew wut its wurth all day long m8".

Completely different mechanisms to airsoft , essentially the air pistol is a revolver in a Glock shell , the blowback is just for effect and doesn’t actually cycle the loading mechanism at all , it just fires straight from the magazine.

Which is also unusable in games if the stated fps is to be believed

It does I have not been a fan of the tan colour, but just loved the 416 in it. It really does look good. Shoots damn good aswell!

I don't see the point of mixing bushing and bearings because as per airsoft physics, the differences and variables affecting the three gears do not make them considerably different from one another in terms of the type of loading and the amount of force behind them The different surface finish on the axles themselves with different gears already makes it impossible to work out the precise newtons applying on a bearing because if it is anything but perfect it is going to have a bit of wobble, and the brand of bearing alone (and the size, and the amount and type of grease, heck even the amount of dust exposed) will determine your shock load capacity of the bearing which is what ultimately makes using bearing worth while for the speed advantage But since every particular setup is different, even the best bearings you can find will have a risk of exploding, again because of airsoft physics and tolerances If you have to be mathematical, the bevel gear spins the most, followed by spur and sector gear, so the bevel gear will benefit the most from the less resistance from a bearing, in theory, but if you are willing to take the risk of exploding bearings there is no reason to not use it on all three gears So it comes down to whether your setup is so marginal that your motor and battery cannot handle the negligible amount of extra resistance from bushings that you have to sneak in one or two or three bearings to lower the resistance, and choosing how many bearings to use is just a matter of risk management, because more bearings = more points of failure In my opinion, bushings work fine, they are more reliable, the speed difference is not worth the risks of failing bearings because they fail catastrophically in almost all cases If you want to put in bearings, I would start with putting on the bevel gear first, then spur, then sector gear, but in reality it does not matter because again, airsoft physics and tolerances is a pure chaotic mess therefore there is no theorycrafting possible, in reality it might even come down to the finishes of your particular gearbox and whether your shimming is making one of the gears rubbing on any one of the bearings, for example, so again, no theorycrafting is possible, because it is ultimately up to you and two million other variables

@The DrabOlive I've had a load of pistols, still do, but first couple of years of playing prob had 6 I think, 3 different brands, ksc, kjw, we, best of them was my ksc G19, & then one day a regular at the chain of sites I used offered me a tm hi-capa 4.3 with 3 mags for £70, had a try on the edge of the safezone, it was actually acrisse, a military training area near Folkestone, middle of winter & absolutely freezing. First few shots I'm like "wow, that's got some snappy kick", & hitting small targets at 30m+. Emptied all 3 mags, 24 bb's in each, without missing a beat I FREEZING TEMPERATURES!!!! 😲. Bought it there & then, still using it probably 20 years later. Buy whatever you like the look of, BUT First buy a tm hi-capa, that way you've always got a perfect secondary to go back to when the others let you down.

Who did the paint removal, Stevie Wonder?

Not really bought, more got I sent in my LeatherMan tool that I purchased back in ‘99 whilst visiting Singapore to the supporting retailer for warranty assistance I was hoping for a sharpen and tighten Instead, they “retired” it and replaced it with the current replacement model Well chuffed! I do carry it on my loadout if that counts

Six days , from ordering to delivery Some of these Ali Exp sellers have really got their shizzle together! My Kydex holster was just annoying me, and low holsters are just ball crunching Hopefully this’ll be better

One thing to consider though... If they are producing another run of the original M60, they normally have a rather comprehensive range of spares. So if you wanted a proper hanger bracket and trigger group for the A&K it may be available. Not cheap, but cheaper than buying a full gun!

Heard on site: "Stop climbing that tree, you've been told." "It's OK, I'm a tree surgeon, I do this all week." "Well, it's Sunday, so down you come." Shouldn't have needed multiple warnings, of course.

couldn’t resist adding one of these to the GBBR collection

How do you get a country girls attention? A tractor.

It's been so cold in our house just lately that the toilet duck has flown south for the winter.

Is there some sort of notion with the Airsoft gods that as soon as you buy a new RIF your car breaks? 😂😂

I once saw a Bob Long 2k2 Timmy with a prototype (raw aluminium) Z frame at the European indoor tournament around 2003-4. It was gopping. And the ICD Bushmaster looked even worse with one fitted. Thank god they didn't become the 'norm'.

I'd like a day off. Like, nothing but films, beers, food. No broken cars, no whining kids, no stressed wife, no work hassles, no broken pews looking at my bank statements giving me a nudge to buy more stuff. Just me, 5.1DTS, Duval/quak, Doritos. Done. Happy. Oh and maybe one of those snow wolf Barrett m82's.... 😁

If santa was pushing the boat out it'd be a TM MK18 GBB, although a shotty tracer would be handy having just got a Breacher. But I think he'll be bringing me a shiny new (bigger) stainless fermenter so I can double the size of my beer batches.

Sort of already started, birthdays Xmas eve so the missus has just bought me the cyma vss that popped up on here earlier, always fancied trying one as it's one of the few soviet bits of kit I like the look of. 🤔

I haven't been yet, but intend to take my air rifles and possibly some airsoft guns to this place, when it gets a bit warmer. https://gowildatthewarren.uk/