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What mosfet would you recommend for reliable 11.1 usage?

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Hi all, looking to achieve best trigger response for my rifle as I prefer to play Semi.

 

I'm currently going to buy a Lonex HT motor, some 13:1 gears, steel shim set, and perform a trigger mod to reduce the pull, now obviously I'm wanting to use 11.1 so I'd need a mosfet.

 

Which one would you suggest getting? Thanks.

 

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you don't NEED 11.1v but depends on motor used and wiring - in fact how well you do your homework

 

mosfet - diy 3034 for about a fiver or less if you wish

but for 1 or 2 builds you can't beat imho the firestorm or F-Storm fet for a tenner

http://www.firestormsystems.com/shop/electronics/mosfet-switch.html

 

up to about 30rps can be achieved on 7.4v but suggest keeping in low to mid 20's

as higher speeds is a bit of overkill and feed issues may arise

 

shs or RA torque - 12:1 gears in my recent build from ak2m4.co.uk

25rps on thick wire & fresh 7.4v = 8.35v lipo

a lot of messing/meshing about getting shimming better on bushings - NOT BEARINGS for speed builds

did hit 30rps with fast motor but feeding wasn't great on auto so what was point....

broke a cheaper 13:1 gear set trying 39+ on 11.1v

 

so yeah trust me don't go tooooooo nutz

shs gears are best bang for buck

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Thanks for the response. My main aim isn't to get ridiculous RPS on auto I cannot stress this enough but I do not like shooting on Auto, all I want is near instant trigger response and most of the guides I have read have suggested what I am wanting to do in my first post. Firestorm looks like a great bit of kit but I'm just a bit dubious as it seems so cheap for what it is supposed to do.

 

So you're suggesting a good HT motor, 12:1 shs gears and a good shim job + bushings?

 

I would still like to use a 11.1 for the sheer response time in the trigger.

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Thanks for the response. My main aim isn't to get ridiculous RPS on auto I cannot stress this enough but I do not like shooting on Auto, all I want is near instant trigger response and most of the guides I have read have suggested what I am wanting to do in my first post. Firestorm looks like a great bit of kit but I'm just a bit dubious as it seems so cheap for what it is supposed to do.

 

So you're suggesting a good HT motor, 12:1 shs gears and a good shim job + bushings?

 

I would still like to use a 11.1 for the sheer response time in the trigger.

 

 

I would suggest get a set of 12:1 if you want to but hold off from installing them

 

Seriously - higher gearing will drain battery and increase load on motor plus even on semi going above 25rps will start to double cycle unless Shortstroking

This is getting into more techy side of things and trust me it involves a LOT MORE WORK and above all ATTENTION TO DETAIL

 

if this is your first or first few builds then stay on 18:1 and run with 11.1v with the mosfet

a stock motor will pull about 20rps on 11.1v so a torquey motor will push you easily into 25rps+

deans and possible upgrading of wiring is a wise decision

 

Fitting the higher speed gears trying to go faster total reshimming nightmares double firing feed issues await if you try to run before you walk

and you will be changing batteries quicker on more stressful builds generating more heat and wear even if done perfectly

 

So maybe consider the higher gears but ease up fitting them perhaps until you get the rest of the box running perfectly sweet

AoE, decent piston & head perfect seals - smooth running, fitting fet, rewire - check feeding on your present mags....

 

TRUST ME - it is not a quick afternoon rebuild

3 weeks of on/off swearing filing sanding dremmel gluing bushings weighing pistons and f*ck knows what else I'm giving up on this pile of crap build....

 

Think you best stick to improving the box as it is and getting her really sweet and then bump some juice in her if needed

gears are good price - motor is a great all rounder and if you want whack some extra juice through her

but maybe ease up installing the super duper speedy gears for now - honest my first builds were right $hit even on stock

it isn't quite as easy as it first seems and often stuff needs a lot of tweaking on top to work properly - plus a smidge of luck I'd say

(even then when you THINK it is all gonna work great you still get the classic techy term - WHAT THE F*CK JUST HAPPENED)

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I would suggest get a set of 12:1 if you want to but hold off from installing them

 

Seriously - higher gearing will drain battery and increase load on motor plus even on semi going above 25rps will start to double cycle unless Shortstroking

This is getting into more techy side of things and trust me it involves a LOT MORE WORK and above all ATTENTION TO DETAIL

 

if this is your first or first few builds then stay on 18:1 and run with 11.1v with the mosfet

a stock motor will pull about 20rps on 11.1v so a torquey motor will push you easily into 25rps+

deans and possible upgrading of wiring is a wise decision

 

Fitting the higher speed gears trying to go faster total reshimming nightmares double firing feed issues await if you try to run before you walk

and you will be changing batteries quicker on more stressful builds generating more heat and wear even if done perfectly

 

So maybe consider the higher gears but ease up fitting them perhaps until you get the rest of the box running perfectly sweet

AoE, decent piston & head perfect seals - smooth running, fitting fet, rewire - check feeding on your present mags....

 

TRUST ME - it is not a quick afternoon rebuild

3 weeks of on/off swearing filing sanding dremmel gluing bushings weighing pistons and f*ck knows what else I'm giving up on this pile of crap build....

 

Think you best stick to improving the box as it is and getting her really sweet and then bump some juice in her if needed

gears are good price - motor is a great all rounder and if you want whack some extra juice through her

but maybe ease up installing the super duper speedy gears for now - honest my first builds were right $hit even on stock

it isn't quite as easy as it first seems and often stuff needs a lot of tweaking on top to work properly - plus a smidge of luck I'd say

(even then when you THINK it is all gonna work great you still get the classic techy term - WHAT THE F*CK JUST HAPPENED)

 

Okay bud, thanks for the good information. I'll grab one of those Firestorm fets and a decent high torque and see where it takes me. It's a G+P V2 gearbox, so don't think I'll need to replace anything, will look at the AOE correction when I open her up though.

 

Another quick one, this is what my AEG sounds like currently, http://vocaroo.com/i/s1dPhcGek4F8 first shot sounds fine, but the following ones are left with a 'thud' sound - what could this be? She shoots really nicely so that isn't an issue.

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I'm at work atm so not easy to diagnose much - not that I know that much....

 

Could be piston slapping against head - sorbothane dampens that with a sorbo + neoprene sandwich

 

A little "Twang" can be a metal spring guide that you might notice when dry firing as spring uncompresses eg metal guide and metal spring = Twang

Can use heat shrink tubing but adhesive type that sticks once shrunk but not used it myself yet.

 

Most likely a thud is piston slap - sorbo+neo mix when correcting AoE will help.

AirLabs do a sorbo pad or make one up yourself and glue with super glue.

 

Do not use bearing piston head, they can come undone if you don't use thread lock and bearings add at least 3gms in top to piston weight in speed builds

 

There is loads to learn I advise you Google up I think Legacy's guide to high speed builds for a lot of info

Some don't quite apply coz we use lower fps limits but is a goldmine of info of what work is involved

 

It is not a quick and easy thing to just slap stuff together

Often old bits n bobs assembled well will work great and better than a load of upgrades just chucked together

 

Often you can spend ages on each part ensuring each bit fits and works silky smooth

The one bit you cut corners with thinking oh that will do will very likely be the bit that fails or contributes to box failing at some point

 

Tried to listen on fone but hard to hear tbh, not sure, but motor height might be out, sounds a little screechy but sound can get a bit distorted listening online.

Think I'm best off listening when I get home tbh

Rather than take stabs at stuff I can't really hear...

 

The F-Storm fet will be fine, thermal fuse protection, ultra tiny price - you would have to go some blow it - as long as you install it correctly.. Not hard just route wires well

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I have a Gate NanoHard in my Scar.

 

All the Gate Mosfets come with a connector so you can turn your trigger contacts into a hypothetical trigger switch and removes the risk of burn contacts for the future. They are also easy to install and most of them are also Fuses.

 

worth a look at

 

cheers

 

alex

 

Ps. some of the 3rd gen mosfets from Gate, NanoASR upward are lipo 14v compattable.

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You are dry firing so it will sound a bit different to shooting bb's

you have a thud from piston slapping against cylinder head - with a mag in there there will be a change in sound from pushing bb out

also you get/hear the slap/thud so bad and if a sorbothane + neoprene sandwich it will dampen and reduce the shock/slap a bit too

(sorbo & radius gearbox will help prolong the life of it from cracking under stress)

 

There is a slight latching sound which could be the motor releasing piston - going nutz with no load after release of piston

then just starting to grab piston again with a possible jolt through gear system in box/motor - could be a bit of lash in there

from worn gears or just shimming out a bit

 

But end of the day, does it shoot ok, motor don't get hot or battery draining quickly then it is fine

I have heard a lot lot worse with dying cats being stung to death by a swarm of wasps jangling a bag of rusty old bolts

 

The sounds can vary a hell of a lot - depends exactly where you listen to right up close or a few feet away....

The final sound of a gun can be changed very easily making a louder pop or f*cking louder pop if you want

on a normal m4 flash hider - carefully wrap your fingers - actually use a bit of duct tape in case you shoot your hand/fingers by accident

anyway - wrap or cover the slits in a M4 flash hider and hear the difference it makes

if you have a suppresor fitted - one with ccw & cw threads - unscrew the very end of it and pull the trigger - jeez it makes a very loud crack

 

So sounds can vary a bit on the exact same gun depending oh how/where you record it and what is at the very end of it

 

You are going to fit a mosfet and check AoE so you can examine closely any wear inside when you service her

try not disturb the box too much - watch loads of tutorials/videos about your same gun type

take pics on your fone - honest read up loads of guides for hints n tips - if you think you will be fine like me.... YOU WON'T

lose one spring when you open up the box as it explodes as you open her - you are screwed

so read and possibly open inside a plastic bag unless you like getting on your knees looking for where the f*ck did that go......

ahhhhhhh - my first gearbox, what is the worse that can happen.....

easy - making an ok-ish gearbox run 10 times worse and yes you will need that spring you lost coz you thought it will be fine.....

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Sorry to be a pain guys, cant seem to work out how to quote!

 

 

Not to hijack the thread but earlier Sitting Duck mentioned not using bearings with high speed builds?

 

Why is this and is this a personal preference or a hard and fast rule?

 

Cheers

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Bearings will quickly collapse if not shimmed perfectly

even then under gears especially on middle spur gear bearings will get subjected to high stress

the underside of spur will get stress from the piston/spring and also the start/stop/start stress of bevel/motor

 

even on super duper £30 ceramic bearing builds the underside of spur gear should have a bushing as a ceramic will fail quicker than bushing

(google & you tube real experts saying this with wrecked bearing results)

 

Bearings can be used for modest builds if shimmed very well but feel that at best a mixture of bushing/bearings would be best

Bearings rotate smoothly and final rps will be a little higher 5% maybe 10% or a couple of rounds per second

this means jack $hit if bearings start to collapse in say 20k to point they allow such movement that gears can strip teeth from bad alignment

 

At best a 50/50 mix of bearings & bushings is perhaps a trade off

but where this mixture is may be open to opinions....

 

BEVEL - bushing on top as it will be subject to stress from motor's pinion as gun starts to cycle

Maybe a bearing below as this is one possible area that that shimming don't have to be 101% perfect

(before anybody flames bevel shimming must be perfect - yes on top for motor height but below bevel it won't be bottoming out as such coz motor pinion is stopping it crunching into spur gear - so the bevel's shimming UNDERNEATH is not that critical like above bevel is what I'm saying...)

 

SPUR - bushing below for sure as mentioned above

maybe bearing on top as most impact is going to take place underneath gear

 

SECTOR - bushing on top is my gut feeling - this is where the sector's teeth are actually meshing with piston and the point where the tension from spring is impacting on these two components creating stress

maybe bearing below but tbh you may as well use a bushing as the sector gear turns only once so the ratio of one turn is not gonna slow it all down really

 

The bevel gear is turning between 6.25 times on a stock 18:1 gear set to 4.25 times on a 12:1 gear set

where as the sector turns just the once plus the stress of spring, piston as well - really think 2 bearings & 4 bushings is most I would ever use

plus bearings are more expensive (a little or mega if using ceramics) and bearings no matter what make/type will possibly crap out before a decent bushing set.....

 

Stock guns or say keeping below 20rps and into the "teens" maybe bearings will be ok

some makers - including Krytac use bearings - which if shimmed very well will be ok but still not last as long as bushings

 

Higher speed or more stressful builds you should be using bushings

or

to put it another way - bearings are nice and smooth on moderate loads

but inside a cars engine the crankshaft is running on solid bearings - or bushings/races suspended in oil to keep lubricated on these very stressful parts of the engine - crankshaft and some other areas coz bearings would just crap out

yes bearings are used in other areas of car & on not so stressful points on engine even

 

but on high stress/wear areas bushings or solid races are used coz bearings just won't last

 

Even G&G soft bronzey oil filled bushings wear quickly when pushed to higher speeds

wear takes place anyway - yes all bearings and bushings for that matter will wear over time....

the wear can be generally even wear (larger inner diameter)

or egg shape or oval wear patterns

or in bearings - they tiny bearings just munch up, the race holders collapse and the inner race just goes all over the f*cking place up/down back/forth so all shimming is way way out of whack and then gears n crap also start dying of greater wear very quickly.....

 

read up but that is what they say and have experienced bearing failure that deffo contributed to a set of gears smashing up within 15k

 

but other than that - bearings are lovely, phew

 

This is just my take on it but was told & read bushings were better for speed/stress builds

and I have found out myself that maybe what I read/heard was correct especially in more stressful builds

suffice to say I'm now not really bothering with bearings or at best maybe just one on top of spur perhaps, not sure about below bevel

and yes they are glued in with either superglue or best results epoxy

 

but this is my personal take or choice atm - it might change as we are still learning and trying various methods seeking to get best possible balance and reliability in our builds

 

opinions though are like ar$eholes - everybody has one but it is wrong to keep shoving yours in people's faces all the time

but you did ask so I gave you a "brief" answer about my current opinion on bushings/bearings

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Sorry to be a pain guys, cant seem to work out how to quote!

 

If you are using IE as a browser that would explain a problem with quoting, I could never get it to work whenever I used IE. So now I look at the forum using the Mozilla Firefox browser (as recommended by other forum members) and everything works perfectly.

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If you are using IE as a browser that would explain a problem with quoting, I could never get it to work whenever I used IE. So now I look at the forum using the Mozilla Firefox browser (as recommended by other forum members) and everything works perfectly.

 

Sorted!

 

Thanks bud!

 

Further to my previous comment would bearings be okay if it was used on short bursts only? or just auto?

 

Also I'm currently doing my first bit of work on my V2 gearbox and intend on installing a MOSFET as the original poster is. Would I need new gears and wiring to run an 11.1?

 

Really sorry for asking probably simple questions but I seem to find such contradictory advice everywhere!!!

 

Also should I make a new thread for this as I don't want to hijack this haha!

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Sorted!

 

Thanks bud!

 

Further to my previous comment would bearings be okay if it was used on short bursts only? or just auto?

 

Also I'm currently doing my first bit of work on my V2 gearbox and intend on installing a MOSFET as the original poster is. Would I need new gears and wiring to run an 11.1?

 

Really sorry for asking probably simple questions but I seem to find such contradictory advice everywhere!!!

 

Also should I make a new thread for this as I don't want to hijack this haha!

 

What make is the gearbox?

 

While in general I go with "if it ain't broke don't fix it" if you have a particularly cheap gearbox then you may find tha the extra strain caused by running an 11.1v battery may wreck it prematurely in which case it might be worth fitting better gears while you have it apart.

 

In pure mechanical terms bearings SHOULD be fine. However, the issue is that for sustained high speed operation ANY bearing requires proper lubrication. Any bearing with heavy enough grease in to stand up to serious abuse will most likely create drag on the gears, light enough grease to not cause drag will not provide enough shear strength to not cause premature bearing failure and unfortunately tiny wee bearings in airsoft gearboxes just don't have the right kind of lubrication in them. A good quality bushing (having no moving parts) should stand up to the battering a bit better as long as they are a decent brand and the right material (cheap plastic ones will fail quickly, decent phosphor bronze or even steel ones would be better). Either way, proper alignment (Angle of Engagement AND shimming) is important and the right gear lubricant is critical if you want to prolong the life of your gearbox.

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Sorted!

 

Thanks bud!

 

Further to my previous comment would bearings be okay if it was used on short bursts only? or just auto?

 

Also I'm currently doing my first bit of work on my V2 gearbox and intend on installing a MOSFET as the original poster is. Would I need new gears and wiring to run an 11.1?

 

Really sorry for asking probably simple questions but I seem to find such contradictory advice everywhere!!!

 

Also should I make a new thread for this as I don't want to hijack this haha!

 

 

Yes bearings will be " OK " - they will very likely crap out after 10-20k depending on stress of the speed build

Not really the burst on full on mental hosing but how many cycles or bb's aprox and the actual stress of each individual build

Yes the initial "jolt" is gonna be more on semi than lots of full auto but tbh it comes down to bb cycles the stress of build and above all how perfect shimming is that really will determine how long std bearings last...

 

Do you need new gears on 11.1v blah blah blah.....

Depends on the motor being used for a start and gears, motor, wiring, spring setup will all alter the ROF

I'm gonna refer to snappy-ness or trigger response or any other bollox as ROF though they are not the same but are kind of linked

not quite hand in hand coz they differ slightly a responsive gun may not always have a higher rof but often they are linked or both improved from std

So the final ROF.....

This will vary - if using std stock ferrite motor you should hit around 20rps on 11.1v with stock gears, mosfet, wire, deans etc.....

 

20rps on 11.1v is ok then basically most stuff can remain stock if all ok and bearings should last a good while

though 11.1v will be wise to use a mosfet soon - or very soon if using a neodym motor

 

Now if you wish to go faster then more money & work plus more stress - for you & gearbox/bearings will happen

 

You can hit 20rps on 7.4v using a neodym speed motor on stock 18:1 gears on say 350mm barrel M4

you will get 328fps to 350fps on longer M4's on m100 but on say mp5k will need m110 -m115 to hit 350fps

So very short guns will require a slightly stronger spring to get to 350fps but this will mean the motor is working a tiny bit more so rof will decrease a tiny bit

Now on top of that you can use higher speed gears though they don't quite give the expected increase as you first think....

 

18:1 vs 12:1 gears - must get 50% more right - NO NOT QUITE

Gearing is actually 18.65 vs 12.65 so you are only on a 47% maths increase not full 50%

on top of that the motor is working harder from stand stil - you try doing a hill start in 2nd gear

(well not quite as bad but a ferrite stock motor will start to show than a stronger neodym motor)

So in real terms your rof may only increase say 35% max is my thoughts on gearing

So if your stock gears are fine then a stronger neodym motor may be an option like shs torque will up stuff by about 25% and be a steady workhorse

plus you can keep motor and replace with old stock motor easily if you upgrade

 

Personally depending on your experience - I mean inside the gun/box experience and for less agro all round.....

 

Replace motor with shs torque and leave for now is easiest option to run on 7.4v or up to 9.6v

no need to open box for mosfet - this is for a v2 btw a v3 box can fit a mosfet all without opening box

Fitting a mosfet isn't hard but you will need to be able to solder and inside a box like v2 careful routing of wires will be needed

then all the other stuff - shimming AoE service & tweaks and the fun of putting it all back together if it is your first box

 

Not too mental or crazy - trigger contacts will be fine, fit a deans connector on gun and that should do ya to get near 20rps

 

if you wanna go nutz - well wtf you can hit 40rps but LOADS of $hit will happen....

piston strips or smashes up so stronger steel rack piston Shortstroking with higher springs mags not feeding batteries running down quicker from extra work, bearings just won't last, gun or box in general just having the crap knocked out of very quickly

Which to be honest is fine if you like gun in bits more often than out using it but that guy with a broken gun in safe zone will be very likely the guy who just kept taking the pi$$ like moi :) - wot a bell-end

 

This why we say 20 is plenty....

 

20rps is easy to do and mags feed sweet

25rps gun starts to over-run, piston being precocked or on some builds can start to double fire on semi

This double firing on semi is your gun's way of saying - whooa slow down you f*cking idiot !!!

30rps is when you then get more problems and mags not feeding very high risk of PE starts to happen due to double firing and the lifetime of box is greatly reduced

40rps - yeah you ain't gonna be playing all day I would say - maybe not make it through to 2nd game of morning.....

 

Yes you can hit 40rps but the work and full understanding of what is required is immense, and I don't care what people say

it is very hard to build a SSG to hit 40rps AND LAST !!!

Anybody can do a gun vid for 40rps and then hang it on wall but you REALLY need to know your stuff to build a gun to hit 40rps

(don't matter what high end battery/motor/spring/cnc gearbox/gears or any other stuff you use the attention to detail is enormous and real wisdom is needed plus a little sprinkling of luck I still say that not one tiny element fails at that speed)

 

So with that in mind I would suggest you try to reach 20rps on bearings and leave it at that for now....

Later on which hopefully will be a while down the line you can replace bits n bobs and go to say 25rps

The best response or difference is gonna be going from say lame 13rps to 20rps - a 50% increase and you will have a nice gun that will last ya

 

until you go nutz from 20 to 30 the difference after 20 to 25 will be slight and therefore not gonna see a massive improvement for money/time spent

You may get to 22rps or 18rps but around 20rps is a good safe lasting improvement without loads of work....

 

Yes AoE and tweaks should be done but feel 20rps is gonna be about the limit without needing mosfet, AoE, rewire, blah blah blah......

So go for it but in stages - by time a 20rps gun starts to go crappy then you can replace bearings with bushings, maybe if gears are crap 16:1 gears or higher speed if your motor has grunt, mosfet blah blah blah

Heck - just buy a new box to build or use as is whilst you rebuild old worn box

 

Loads of ideas/options - Fire-Storm or F-Storm Mosfet is great for a tenner if you want a good cheap pre-built one

but see how you go and think about how fast & how much time/money you sink into it all

 

a good read is Legacy's guide to high speed build - US using higher springs/limits but a good read

though don't take it as complete 101% gospel coz we can't run with m120's as is on 350fps UK limits

so the actual findings/results slightly differ for us Limey's

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