Gearbox Lock-ups.

[Cr0-Magnon]

I've been using my Novritsch SSR4 quite a bit recently and overall I am happy with it.

However the last game out, I was getting lots of what I'm going to assume was "lock-ups" as the gun would stop firing, until I switched around the fire selector..... although they could be solved by switching it back to safe.

Would that be plausible for a lock-up or does it always need to be switching to full-auto?

I'm possibly guilty of spamming it in semi (it was a "target rich environment") but thought having a MOSFET which is supposed to offer full cycle detection would prevent that?

My other question is, is there any correlation between pre-cocking and lock-ups? I'm using 2 x FPS adjuster rings, which add compression to the spring. With that in mind I was using it only on 2 out of 5 on the pre-cocking scale. So I'm wondering whether less or more pre-cocking would be helpful?

 

[Adolf Hamster]

I'm assuming the ssr is one of the gate optical mosfets?

Typically a "lock up" is a function of the cutoff lever, so a gun with an optical cycle detection can't lock up the same way you'd get on a mechanical trigger unit.

There can be a correlation with precocking, the stronger the spring/higher the precocking setting the more starting load the motor will be under, that'll also get augmented by high speed gearing. Motor might not fully stall but might draw enough current to trip the mosfet's current protection.

 

[Cr0-Magnon]

It's not a Gate, not sure if it's optical or not. It's the one pictured below.

I'm using 11.1V Titan batteries too, if that has any bearing.

I was just messing around with the pre-cocking settings. I couldn't see the difference until 4 out of 5, at which point the piston came back as far as pictured...which I'm not sure is too far or normal for pre-cocking?

View attachment 101450

View attachment 101452

 

[Adolf Hamster]

It's not a Gate, not sure if it's optical or not. It's the one pictured below.

hmm, it doesn't look like it's running and obvious levers that interact with a col (like the old school ascu's), and "cycle detection" generally inferrs something watching the sector teeth rather than relying on the cam.

I'm using 11.1V Titan batteries too, if that has any bearing.

it might put notion to the idea of it being an over-current situation if the battery is meaty enough to feed what the motor's asking for.

I was just messing around with the pre-cocking settings. I couldn't see the difference until 4 out of 5, at which point the piston came back as far as pictured...which I'm not sure is too far or normal for pre-cocking?

it really depends on the specific build and your preference.

to me your picture is what i'd call "adequate", but then my hpa days kinda made me a tad obsessive about minimal lock time.

mechanically, there's not really an issue with any level of precocking as long as you de-stress the spring before putting it in storage (afaik perun mosfets have a function for doing this), you'd want a build worth its salt to be able to start from any point in the cycle.

electrically, the more precocking, the more load on the motor on startup, the more current it'll draw and if the mosfet doesn't like it then it'll either cutout (if it has overcurrent protection) or in the extreme go pop.

i'm wondering about those compression rings, do they clear the piston ok? it might be worth looking at running a stronger spring without the rings to see if that helps, might be if the piston clips the rings it locks up (once had a box do that on the spring, when the spring was compressed it expanded just enough to bind up inside the piston and lock it to the rear)

 

[Cr0-Magnon]

Even on 4/5 for pre-cocking (which is higher than I've ever run it), it didn't look like the compression ring and piston met.

I'm wondering about the battery side of things now. It was omitting one short beep every time....

View attachment 101464

 

[Adolf Hamster]

Even on 4/5 for pre-cocking (which is higher than I've ever run it), it didn't look like the compression ring and piston met.

it's more how far the piston retracts during the shot before it slips off the sector gear, which isn't affected by precocking.

I'm wondering about the battery side of things now. It was omitting one short beep every time....

that's definately pointing towards it being an over-currrent or similar system, lowering the precocking might help it enough, as will a weaker spring (if you're happy to take the energy drop that'd give).

11.1v won't be helping either, more current through the motor (and by extension the mosfet).

other option is if your situation allows try using bursts of auto as opposed to semi-spamming, less of a stop-start loading will be less load on the motor.

 

[Cr0-Magnon]

Interestingly I removed one of the FPS rings and the FPS didn't drop ?

I tried a 9.9V LiFe and it didn't like it at all, sounded very laboured.

I've also changed full-auto to three round burst. Will try to use that a bit more tomorrow.

 

[Adolf Hamster]

Interestingly I removed one of the FPS rings and the FPS didn't drop ?

hmm, that's an interesting one, i can see it not dropping by much, but it should definately be dropping a tad.

however if it hasn't then no reason not to keep it that way.

I tried a 9.9V LiFe and it didn't like it at all, sounded very laboured.

lower capacity/current rating?

I've also changed full-auto to three round burst. Will try to use that a bit more tomorrow.

that'll help, although wether or not it'll help enough is hard to say.

 

[ak2m4]

From what I've been told the fet the ss4 uses is the same / very similar to the ChiLuns, it could be that the one of the micro-switches is failing.  Had it happen to one of the test ones.  Maybe email and Nov support and they might put you in touch with the guy who does the UK support.

 

[Fatboy40]

From what I've been told the fet the ss4 uses is the same / very similar to the ChiLuns, it could be that the one of the micro-switches is failing.

From this photo it looks like micro-switches...

https://eu.novritsch.com/wp-content/uploads/2022/06/ETU_SSR4-600x600.jpg

... and for a rifle that costs around £270 (with the metal receiver) I'd maybe be expecting something a bit better? (in the context of what you get with a Double Eagle M900 or a Specna Arms with a GATE Aster).

 

[Cr0-Magnon]

As an update:

I'm now convinced it's a case of overheating rather than lock-up.

I tried the gun again on Sunday, in a much slower pace game (ie fewer direct "targets"). However the same thing started happening before I'd even gotten through 150 rounds. I contacted Novritsch customer support and after a few days they replied that it's likely one of two things:

1) ETU was damaged by me incorrectly inserting the body pin that kept falling out (I highly doubt this, feel like it's a cop-out, besides should I have to sort something like that out of the box?)

2) Motor is not set at the correct height. I've never messed with motor height before, as assumed they'd be put together at the best setting. I did however follow their instructions and by tightening it one turn, the gun was noticeably "cleaner" sounding (more thwack, thwack than whirring/slight whine).

So I'm left hoping that's sorted it...or failing that, they give Luke @ Negative Airsoft the thumbs up to work on it under warranty.

 

[Leo Greer]

It does sound like you’re overheating, but not because of motor height or bad installment.

I suspect the gun is pulling more amps than your batteries can handle. Have you tried on an 11.1v LiPo with very highly rated discharge? Since companies lie about their discharge and milliampere ratings, that’s the easiest way to make sure.

Titan Li-ions are really not suitable for airsoft, given the low discharge Li-ions actually produce. There are slight differences between packs, but here’s a comparison of a few: https://www.airsoftsociety.com/threads/objective-battery-test-titan-lion-vs-kypom-lipo-vs-hv-lipo-valken-others.161379/

I have personal experience with *this* pack. It confused me for ages as a new player trying to figure out why my gun wouldn’t cycle (outfitted with 13:1 and 30K), and it took me over a month to realize that the battery didn’t have enough juice.

Your 9.9v LiFe obviously doesn’t have enough discharge—does the Titan seem like it runs out of juice faster than it should? When batteries are on the edge of being able to run your gun, but they’re still being overdrawn, it’ll still run your gun, but it takes up a lot more juice. Hence why LiPos puff when they’re bad quality or under spec for what you’re doing with them.

 

[Cr0-Magnon]

The battery Novritsch recommends for this (and even the 1.5J version) is 11.1v 30C.

According to Titans website:

C Rating: 16C (equivalent of a 1600mAh 30C)