13:1 gears in a V2 gearbox

[Animalben]

Good morning/afternoon/evening.

I've decided to mess around with a Nuprol freedom fighter I have that seems to be a bit of a pup/lemon for me. I am thinking of putting in some 13:1 gears into the gearbox as well as a few other things to the gun, but looking at bits around the tinterwebs people seem to be using a higher power spring, can anyone shed a little light on this for me? Would be greatly appreciated.

TIA 

 

[Prisce]

I may be a little thick (read half asleep), but I’m not entirely sure on the question your asking?

 

[ak2m4]

Yeah question is a little jacked up, Ben tell us the problem with your AEG, sure we can help..

 

[Animalben]

Yeah I think I haven't worded it very well. Was half asleep when I wrote it.

I am messing around with a gun of mine that has given me a fair few problems since I've had it, instead of binning the gun off or selling it, I am going to use it as a project and a tinker gun so I can learn/get experience with servicing and/or upgrading. 

I have decided to try some 13:1 ratios gears for an increased ROF, in the brief bit of research I have done on this, I have read that people say to use a M120/M130 spring, but don't seem to say why they use it.

Is there any reason for a stronger spring in with that ratio of gears or are people using having the gear box open as an excuse to put in more power too?

 

[Adolf Hamster]

either more power, or they're talking about dsg builds where you need to up the spring power to account for the fact you're firing only half a stroke.

 

[Sitting Duck]

Yeah I think I haven't worded it very well. Was half asleep when I wrote it.

I am messing around with a gun of mine that has given me a fair few problems since I've had it, instead of binning the gun off or selling it, I am going to use it as a project and a tinker gun so I can learn/get experience with servicing and/or upgrading. 

I have decided to try some 13:1 ratios gears for an increased ROF, in the brief bit of research I have done on this, I have read that people say to use a M120/M130 spring, but don't seem to say why they use it.

Is there any reason for a stronger spring in with that ratio of gears or are people using having the gear box open as an excuse to put in more power too?

Higher spring is used in higher rof guns BUT they shorten the stroke

taking off say 3 teeth from the 16 tooth sector gear = 13 teeth/9mm shorter stroke

lowering the power/energy as higher spring is not compressed fully

Thus lowering a m120 to say a m105 (each tooth removed roughly = losing a m05)

You need a metal of part metal rack say 50/50 mix so the 13th tooth on piston

that becomes the new final release tooth - plastic last tooth won't last long on a higher spring

TM high cycle guns use a 13 tooth sector gear - which is a short stroke sector gear...



1 or 2 or 3 teeth are taken from the pickup/start/left of the gear

the FIRST TEETH that engage/pick-up the piston

NOT the last/release/right side as it messes up tappet timings

This is called Short Stroking or SS a few teeth but a bit of work with a dremel etc....

most people's builds won't need this stuff - you can get to a 20~24 rps gun before needing to SS

should be able to get near to 20rps with a drop in SHS HT motor or RA HT

(don't buy a High Speed motor - a bit too quick and depletes battery quickly after drawing lots of amps/heat)

If you have a problem - describe problem in detail more

TBH - think that gearbox has a micro switch so wouldn't go nutz as them switches burn out

if you push the amps a lot without a mosfet

Changing gears sets - likely you could mess up with shimming a new gear set at your first attempt

(but if you don't try you will never ever start to grasp the concept)

think it is a quick change spring so that makes opening gearbox easier

but all the same you need establish just wtf the issues are, what you aim to achieve and budget etc....

Personally I would not be sinking vast amounts of time & money into that gun

but the gearbox could be an easy to open box if you have to get your feet wet

if all else fails and you screw up you can always buy another gun or another drop in gearbox perhaps

but really list out your issues and gripes first

13:1's will fit in no problem like G&G gearboxes are they don't have rear re-enforcement

(like D-Boys, Cyma, King Arms & others)

video...

Luckily - your box like G&G v2's shouldn't need this mod crap

Yeah there is a lot of "fun" to be had with some of these poxy toy guns

figure out what you want but as said I wouldn't go ultra nutz tbh

 

[Animalben]

Higher spring is used in higher rof guns BUT they shorten the stroke

taking off say 3 teeth from the 16 tooth sector gear = 13 teeth/9mm shorter stroke

lowering the power/energy as higher spring is not compressed fully

Thus lowering a m120 to say a m105 (each tooth removed roughly = losing a m05)

You need a metal of part metal rack say 50/50 mix so the 13th tooth on piston

that becomes the new final release tooth - plastic last tooth won't last long on a higher spring

This is called Short Stroking or SS a few teeth but a bit of work with a dremel etc....

most people's builds won't need this stuff - you can get to a 20~24 rps gun before needing to SS

should be able to get near to 20rps with a drop in SHS HT motor or RA HT

(don't buy a High Speed motor - a bit too quick and depletes battery quickly after drawing lots of amps/heat)

If you have a problem - describe problem in detail more

TBH - think that gearbox has a micro switch so wouldn't go nutz as them switches burn out

if you push the amps a lot without a mosfet

Changing gears sets - likely you could mess up with shimming a new gear set at your first attempt

(but if you don't try you will never ever start to grasp the concept)

think it is a quick change spring so that makes opening gearbox easier

but all the same you need establish just wtf the issues are, what you aim to achieve and budget etc....

Personally I would not be sinking vast amounts of time & money into that gun

but the gearbox could be an easy to open box if you have to get your feet wet

if all else fails and you screw up you can always buy another gun or another drop in gearbox perhaps

but really list out your issues and gripes first

RIghtyho,

The gun does have a micro switch, which I've had to have replaced 3 times I think, within 18 months of having the gun, it seeming to break on the third day of use or so. The original gun tech who replaced it told me it's a known issue with the gun and it will just need replacing if and when it does go. The second tech to look at it basically told me Nuprol are the devil and I must be pulling the trigger too hard. 

I did start pricing up a new gearbox to drop in with the second gun tech, and after a bit of back and fourth he seemed to price one up for around 270 (a bit more than I paid for the gun in the first place) this didn't sound right to me, as part of his rebuild/replace I was buying a full gearbox (ares model for around 115 quid) and then extra bits to go inside.

I have subsequently bought more guns anyway and I haven't thought about this gun really since. At a local gun shop I held a Vector and decided I want one, but was pointed out to me that I do have a gun that's just sitting there, so a project is bourne.

I'm not after a crazy ROF but as I said I am going to use it as a project gun, rather than an interesting looking door stop.

I have had a feeding issue last time I used the gun, which was a new one, seemed to be double feeding the ammo, I took it apart at site and the bucking rubber was all creased up for some reason so straightened this out and this seemed to sort the feeding issue but then presented me with a weird issue with the mags. After about 50 or so rounds with a hi-cap mag it would almost push the mag out of it's own accord, not fully out as the mag release hadn't been pressed but out enough that it stopped feeding. Havent used the gun since as I bought yet another gun anyways.

So things in my head to do or attempt are the following

13:1 gear set

New Hop up (thinking rotary)

New trigger (I like the look and feel of a flat one)#

I am also not opposed to trying a new micro switch if you guys think a "better" one will stop it breaking but I was told this wasn't possible by the tech.

That's probably a lot of waffling and not very coherent, apologies

 

[Sitting Duck]

So things in my head to do or attempt are the following

13:1 gear set

New Hop up (thinking rotary)

New trigger (I like the look and feel of a flat one)#

I am also not opposed to trying a new micro switch if you guys think a "better" one will stop it breaking but I was told this wasn't possible by the tech.

That's probably a lot of waffling and not very coherent, apologies

13:1 gear set - will work

New Hop up (thinking rotary) - hmm if so just buy a cheapo shs/element plastic one

(pro-win cost money and "can" be picky in some guns

New trigger (I like the look and feel of a flat one) - DOUBT IT

The trigger is bespoke in these micro switch boxes

actually the whole f*cking trigger/Cut Off Lever is bespoke

but micro switch is not that bespoke - just a case of finding the industry std switch

w@nky trigger system...

https://www.begadi.com/begadi-hw4-abzug-komplett.html

bespoke COL...

https://www.begadi.com/begadi-hw4-cut-off-lever.html

you see it better in the gearbox/switch pic

all in all a bespoke wanky gearbox tbh

(email protected ??? w@nky or w @ nky - ok use wanky instead)

good idea with quick change spring but the micro switch system is prone to failing

be it the switch, the trigger (not so common), plus long term the odd qwirky bespoke COL

If ever there was a gun that should have had a mosfet fitted as standard to stop the micro-switch burning out

yup it was the Nuprol - Action Army - HW quick change gearboxes

as I said I wouldn't go ultra nutz on it

I'd be tempted to consider a £60 replacement gearbox

or rebuild one maybe - or maybe just forget sinking money into it

But tbh I'd try really hard not to sink too much time & money into it

just keep it ticking over and keep as spare/back up gun as is

save the money for a better gun or tweaking something more worthwhile

The gun looked a good idea on paper but the gearbox is a bit bespoke and can mess up

then you find out some bits are not so easy to swap out around trigger-switch-COL etc....

 

[Animalben]

Unfortunately that is the sentiment I have had from a few people, that it's not worth the time/money/investment. When it works the gun feels good (to me at least).

So it seems to be either sink a tiny bit of money into it and don't expect much

or 

buy the Vector

or 

be happy with the guns I do have lol

 

[Sitting Duck]

be happy with the guns I do have lol

That is best advice...

If only it was that easy - but alas humans are never fully content

If you want another gun & can afford it then buy one

but be careful coz there are certain guns you THINK you want/need

but after buying these "must have" guns - you may soon wish to sell on

a L85 is a good example of this, often people sell on or just keep as a token gun to own

than really use it like they thought they would prior to purchasing

Not saying don't buy this or that

just sometimes the gun you think you want doesn't always live up to your expectations

plus certain bespoke guns can be a bitch to source cheap bespoke batteries or low cost mags

decisions decisions - only solution is - just buy more guns....

 

[ak2m4]

£270 quote for a drop-in! that's insane lol.  I just finished fitted out 2 E&C QD gearboxes with SHS 13:1's, works great without having to mess around too much with the internals.  As Duck says, keep it simple.  Cheap plastic rotary hop chamber.

 

[Iceni]

I'd be tempted to consider a £60 replacement gearbox

I'd go cheaper than that.

AK2M4 has a v2 box for £45. I've looked at it myself as a spare. Downgrade or even cut the spring. And whack it in.

You haven't got space for a mosfet, so there is no point is having that done.

https://www.ak2m4.co.uk/internal-parts/gearboxes-complete/ec-complete-gearbox-qd-v2-rear

It looks like a decent set of internals as well.

I'd perhaps add an oring air nozzle.

 

[Sitting Duck]

Indeed - saw Pete had one on FB but didn't realise he had started stocking them

Specna/EC - quick change spring but reg switch

THAT was the box Nuprol should have used

Could just simply swap his old spring out of his Nuprol box

or

go nutz SS 3 teeth but still might have to drop any spacer inside piston

(did a hot cm517 SS 3 teeth & removed alloy piston spacer and got about 335fps)

has a full metal rack - but yeah just use Nuprol spring as both are quick change boxes

yup not much wrong with that box & miles better/reliable than Nuprol micro switch box

If you walk on water and really take your time a micro mosfet can be squeezed in....

Not humble me but some very clever & meticulous mofo's work

Good shout sir - about op's best option than get ripped off by techs/redoing the Nuprol box

 

[Iceni]

Good shout sir - about op's best option than get ripped off by techs/redoing the Nuprol box

Reworking a nuprol is like opening pandoras box.

You replace the contacts, the COL, the trigger, Add in a v2 saftey lever, Replace the selector plate, then realise you need a new gearset to kick the COL correctly. It would be easy to spend £45 and have nothing to show for it, other than time wasted.

How nuprol get away with a microswitch without a fet is criminal. It's engineered to fail, An arcing microswitch is a dead microswitch. Even in perfect running conditions the added resistance and heat build up on them embrittles the mechanism and causes premature death.





 

 

[Sitting Duck]

indeed - even though places like Begadi stock the crappy bespoke bits n bobs

it just ain't worth it - same as HW helmet World (snigger), Action Army or whoever

them boxes are asking for grief long term and sourcing bespoke parts or agro converting

The EC/Specna box is what should have been used - tried n tested box but with QD spring

even the switch on EC is like the G&G or SHS non-prong/contact copper plate selector

everything looks sound - bar an o-ring nozzle like you said

not sure if bearing spring guide but no mega disaster

not re-enforced at rear so high speed gears can go straight in like G&G boxes

Even stock gears look similar to JG stock gears though can't see the underside of bevel

but I personally give JG gears the edge over many other stock cheapo gears

so the stock gears "look" sound too

It is still a quick change box so easier for novice to work on getting their feet wet

For £45 in UK that is damn good quick replacement box

considering a stripped piston will cost you say £7~£8 for a SHS full rack piston alone

if ya box wrecks to bits inside or shell cracks - there's ya answer & swap spring over

 

[ak2m4]

It's an awesome little box, gave it a good running last week with the stock 18:1 gears, 7.4 and 22TPA motor and it purred along, been trying all sorts of combinations since then.  Also tried it with the stock gears running for a short shoot to see if I could break them, no luck.

Found SHS gen 4 gears worked the best (the black ones).  Spring guide comes with a bearing btw, compression out of the box is super tight.  Personally I wouldn't even bother upgrading the cylinder head, piston head or nozzle - seems so good.  Fitted aluminium SHS cylinder, piston head and nozzle on one to test compatibility and it was perfect.  Fitted plastic and aluminium Prowin style rotary and again no issues.

Darn impressed with the piston as well.  The internal wall of the piston was 1mm thicker than standard pistons, hopefully going to stock these separately as I think would be a nice alternative to the CYMA.  Tested with a ZCI M100, was 340 on the nose with .2's

 

[Iceni]

You just made me pull the trigger on one of those boxes @ak2m4

Got a barrel and a rotary hop unit as well.... You are a bad bad man.

It's all going to go in the GR300.... Should finish it.

 

[ak2m4]

nice one mate, is that the G&G version?

 

[Iceni]

Yeah It's the limited edition version with the magnesium body. I got it very cheap a few years ago because it was in poor condition. The gearbox that was in it has been a travesty. The original magnesium shells have been lost, Someone put a pot metal king arms shell set with a G&G ETU in it, It ate the wires at the pinion because the old casts were thicker. So It's been one of those guns I look at and think I'll drop a new box in it at some point. I did think about converting the box back, but for pretty much the same reasons as this thread (going on the never never with compatible parts) I never got round to it.

It's rear wired onto a solid stock, but I have the wire stock as well. I may at some point change it back onto the wire stock, but the weight distribution on the solid stock is really good. Or I may pick up the upgraded Dboys wire stock. It'll depend on how much I enjoy it, It has a lot of competition, My AUG a3 is absolutely silent, and my G3 is just a beast, So It'll have to be special for me to want to use it.

https://www.evike.com/products/28229/

 

[ak2m4]

I got one short version of this when they came out, 15 years ago?? lovely.  Not sure mine has the magnesium body, it certainly feels different to most metal bodies.  After the first game the gearbox imploded lol G&G were the worst back then for QC it seems.  You have to get the original wire stock back on it ?