Overspin issues, I think...

[bejoja]

Hi all!

So, I made the large mistake of taking on a project I didn't really know how to complete correctly.

I wanted to create a high(ish) speed setup.

Got all the parts and put em' all together, and there's a few issues with it.

While it does work, it's only to an extent.

On semi auto it seems to only fire every other BB and on full it seems to fire 3 or 4 then then the BB's stop.

I've checked the resting place of the nozzle and I've noticed it's in a different place each time.

Anyway, I've done some research and would like to try an AB mosfet to stop the overspin and a delayer chip for the full auto issue.

But before I get them, I wanted to ask all of you to see what you think would be the best thing to do at this point. I have a list of the relevant parts I'm using below.

Thanks in advance!

Lonex A1 Motor

Full metal 14 tooth piston

M120 Spring

11.1V LiPo

SHS 13:1 Gear set, 2 teeth removed off the sector gear

3034 MOSFET

(Please don't tell me I've horribly messed up somewhere xD)

 

[Sitting Duck]

overspin is one matter but sounds like you got feed issues

for starters - a delay clip

removing teeth must be done on the first 2 teeth that engage piston not last 2 that release piston

or you get tappet timing/feeding issues - I screwed up following a wrong guide and removed last 2 teeth instead of first

A large delay clip is a must - though a DSG don't use them but timings are critical and trickier to build/rebuild

Stronger tappet spring - lose a coil or two if trying stupid speeds

My first bit of advise is try 7.4v - this should knock you down to 20-25rps rather than 35rps

see how she goes on 7.4v in 20's

If you changed bucking - check bb's actually plop into hop unit

some bucking/hop combinations can have lips too tight and you have to ram the bb through

it should fall into hop unit, sit just in front of lips and with a MODERATE push of screw-driver (carefully) or use old nozzle push through with mild pressure - can't tell you exact force required but if it is too tight - you will know it

your main problem is you are running 11.1v straight off, that should get you 30-40 rps

which without testing it in stages you will very very likely suffer feed issues not really bad overspin on m120

could be the above areas or your mags themselves - but tbh they should feed on semi ok as most people will struggle to shoot more than 10rps - on semi

And normally you get a gun feeding well on semi no problem but struggles to fire brilliantly on full auto as there is such little time or room for error chambering round after round at much higher speeds

Is why we tend to stick on about mid 20's - there isn't a massive increase that you really really notice at crazy speed/response

it is a bigger headache the faster you try and go - and even with a bad ass hose machine you still get taken out by a pistol pro or a spotty 12yr old JBBG kid camping

The main issue with feeding is paying ultra close attention to hop/bucking area and ensuring you do your homework selecting correct nozzle, increase tappet travel by sanding plate and other mods, slightly stronger spring on tappet - you did check it all fits and aligns perfectly.

Then there is the hop/bucking combination - some hop units work better/worse - madbull & pro-win units are one example that they work for some people/guns and not for others - some hops are just made a tiny bit different/tolerances - some buckings won't work too good either in some hops - tight or protruding lips - plus bad fitting together - yup just the hop itself can be a nightmare getting it just working properly - and we haven't actually got down to accuracy or nubs & whatnot yet.....

On top of all this.....

When you reassemble the bastid - even screwing the box back in receiver you can pull or tilt the box out of true alignment to the hop unit so that it rubs or catches and never feeds or seals properly as it did before

it is supposed to go - gearbox pins, then pistol grip then stock tube but watch out when tightening stock you don't pull box back and tilt the front of box upwards so nozzle rubs on hop at top of nozzle plus not so perfect seal

OH YEAH - this teching crap is a walk in the park - NOT

try to walk on 7.4v before you try to run like the clappers is best sound advice

it is not quite as easy as many including myself first think

ps - I presume you have a v2 box, which is a little more tricky imho to tech for first timers

before anybody flames me or says nope....

The v3 usually has a motor in a cage/frame that can test quickly

the switch means most fets can soldered outside the box rather than inside on v2's

plus I'm sure the tappet travel on a v3 or some v3's is a bit longer than a v2 without mods

so a v3 imho is a tiny bit easier to cut your teeth on so to speak - still need a lot of close attention to detail

but a tad slightly easier due to motor cage and no internal wiring to have to arrange or risk chewing up fet wires etc....

 

[bejoja]

Man! I really wasn't expecting such an extensive, well put together reply! I really appreciate it

I'll order a delayer chip and luckily I already have a 7.4v LiPo. Once that arrives I'll reassemble it, use the lower volt battery and see how it runs.

The teeth I took off were in fact the front ones so there shouldn't be an issue there. On top of this I think I'll also buy/borrow a new mag to double check that.

As for the tappet plate, I purchased a new one when I did all the upgrading as it was recommended that I do so. I'd hope this means that the spring would be strong enough?

The hop/bucking however is stock, though by the sounds of it I should definitely be upgrading it and paying much closer attention to it, so I think I'll look into getting an after market one. Will also be reading up on what would be the best combination and what works well together.

Also, it is indeed a V2 gearbox.

Again, thanks for all the help, greatly appreciated!

UPDATE:

Installed a delayer chip, went down to a 7.4V LiPo and now the gun's working perfectly fine