RostokMcSpoons

I bodged it back to pre-MOSFET wiring, and it still does it. So the there's definitely something wrong with the trigger / COL assembly. I've got some slo-mo video too... very instructional! I can see the contact dolly moving up and breaking contact on the semi shots, and shuttling back and forward whilst flat on the burst/full shots. I'll edit them down and upload them to YT shortly. The interesting thing to note is for my first video I used a thicker piece of card to block the full-auto contacts, and that seemed to help it stay semi-auto. When I recorded the second I just used electrical tape ... and eventually it does the burst/full. In any setup I find that once it's started to do it, it keeps on doing it. Maybe something is sticking? I'm using silicon gear lube from AK2M4 sparingly on the moving parts - but perhaps it's too viscous? Should I get some silicon spray in there to thin it down? Edit: Decided the one video was enough: the first couple of shots go on semi correctly, it's all downhill from there... Epic slo-mo sounds Edit2: Ah sod it, I bought a replacement Rocket trigger unit and COL from @ak2m4 ... let's see if those will help at all.

The spring does look a bit awry in that previous pic, but it looks ok to me now... The sector gear has 2 or 3 shims underneath and 1 or 2 on the top it so yeah it doesn't seem that likely to have got it out of position. Another reddit thread suggested going back to 7.4v, so I've just tried that. Same thing. So pretty sure there's a mechanical issue hidden in this thing somewhere! When lunchtime arrives, and I can spend some quality time on this, I'll change over the contacts (which I don't expect to fix it) and then record some video. It'll give me a reason to try 'Slow Motion' mode on my phone camera for the first time ever And if I get really, really, really stuck with this I'll try to put it all back to pre-MOSFET mode to see what happens then.

Yeah, still bursting on semi. I haven't seen any method to switch off AB on the Merf. I think I should have bought the Perun just because it has more tweakability I haven't really worked out how the COL works, in terms of interaction with the other components, I'll need to need to find an explanatory video later. But I had checked it moved ok and it didn't look like any bits had broken off it. (Remember, I did have a problem where the piston broke at the back, when the piston head came undone and ended up half way down the spring, so there's definitely potential for something having gotten buggered. But of course that happened after I had the first instances of semi not working. Original piston put back in and seems fine so far. I've also got a gouged bushing under the bevel gear that I'll need to replace shortly. I redid the shimming in the gearbox last night and discovered that problem, so I'll order some new 7mm bushings to sort it.) This isn't a DMR build, it's just the site has some CQB tented areas where we can only go to Semi, so even bursts would make me unpopular Edit: Hmmm I just searched on F2000 COL, and apart from the fact it's considered a 'bad design' and an 'achilles heel', at least with the G&G version, I also found mention of the COL not engaging with the sector gear due to shimming. I have had to shim the sector quite a bit as there was a lot of play initially... maybe I need to shim the COL as well?

(Probably 'bad form' to bump my own thread after I replied last, but 'what the heck') Stripped the gearbox down to take a close look at the trigger contacts. and check alignment of everything. The contacts on the dolly looked like they were touching the front contacts on one side, so I widened the gap slightly so only when the dolly moved forward would it contact either of the sprung arms... somewhat like this pic nicked off t'web... (actually the main contact goes much further forward between the two arms when the trigger is pulled) I thought that might fix it. It didn't. I've just tried setting the FET to do SEMI/SEMI as the firing options, but the darned thing only does SEMI/BURST so I can't use it on site unless I sort it Having it on SEMI/BURST, it does do the three rounds properly, but can still do it even with the full-auto contacts blocked with a piece of paper. @ak2m4 is there any mileage in ordering a replacement trigger unit, do you think? I'm also still waiting on a proper reply from Gate, though they've acknowledged my ticket has been raised. Edit: They just did. First step is they want me to solder the signal wires directly to the front contacts. "It seams that the problem is with the trigger contacts. F2000 is a rare replica and honestly we do not have one in our armory but we will try to help you as much as we can. In first step we would recommend to desolder these wires on the photo and then solder only signal wires from Merf directly to the gearbox trigger contacts and check if the semi-fire mode works as it should." I could point out that's electrically no different but I guess I'll just go ahead and do it anyway. Then I'll ask them if they have a Steyr AUG as that's the same setup isn't it?

I've taken the same journey, so you might want to catch up on my thread... I haven't changed the motor or barrel or hop unit... I'll be interested to see how you get on if you do change those, so please make before and after accuracy tests to prove what changes are really the most effective.. That would be very helpful to the community I'm currently very happy with my gun after the change of spring, bucking and nub, but would always welcome more accuracy. The motor is fine (IMHO) , especially when driven by an 11.1v battery Your shopping list looks the same as I'd make. So good luck ?

I've taken it apart again and checked: The plastic trunnion was correctly located into the gearbox shell. The dolly seems to move freely back and forth against the spring pressure. My pic shows it elevated but that's it's natural backwards position. Pulling the trigger moves it forwards and slightly upwards. I don't know, but it all looks the same to me as it's done before (when it worked, pre-MOSFET) I'll ask the Gate tech support if they've seen anything similar Edit: Set up a support ticket with Gate this morning, let's see if they have any ideas. I referenced this thread, so y'all be on your best behaviour, y'hear!

In spite of appearances, the trigger contact isn't quite hitting the other one, so this was a successful single shot. I presume your talking about the arrowed piece? So yeah when it works I can see it push up. When it doesn't the thing shuttles back and forth like a loom loon Are you saying something's gone out askew on treadle? This is a possibility. Back when I was first trying to put this gearbox back together, I had terrible trouble with the plastic trunnion on the lower side of the gearbox, it'd slip from it's locating position on the gearbox and push the tappet plate up and out of position. I tracked the problem down to a missing grub screw... not having one to hand I used a bent nail through the hole to hold it place... I could take the gearbox apart to ensure it's still correctly located, but I'd expect it to bind altogether if it had moved out of position again. But if you think it's worth a look, I will

Nope. It's odd. I move the trigger gently and slowly back, I'll get one or two or three shots. Yank it back and even with electrical tape or paper blocking the contact it'll run full-auto until I release the trigger

Oh dear. It does shoot, and doesn't stop like it did before. But single-shot still doesn't work correctly. I sometimes I get single shots, but more often I get bursts of shots (and yes, I checked the settings to make it's set to single/auto) Here's how it's set up now: I can only try moving the signal wires to the front contacts, can't I? (Edit: no, that's no different electrically than what I've got now) Maybe I ask Gate tech support tomorrow

First step done... Cutting the two wires below the tags now... (this is the nearest I'll ever get to Mission Impossible...) Do I just cut them as near to the tags as possible? I did try to de-solder from the tags, but the solder just won't melt So... The yellow crosses are cut The yellow lead is discarded The black/red is redirected to the motor (green) The signal wires (purple) are soldered to the tags ...?

Ok, after a nice night in the pub and a good sleep, I'm back. Thank you both for the diagrams... I like to think that, self-deprecating humour aside, I'm a reasonably intelligent man, but I think I have a blind-spot for electricals and electronics, and so I'm going to ask for some step-by-step confirmation of what to do. And in this case, quite literally, the blind-spot is what to do on the underside of the gearbox. Do I need to clear both the trigger contacts, to fit the double signal wire? Or do I re-connect one of the existing wires to the front connection, so it's back to how it used to be?

Yeah, seconded as my TM AK47 isn't feeding well on full auto after its 'upgrades'. If it's your only gun then my advice is to use it until it breaks (which might be a while), and concentrate on getting closer to the enemy (decent camo / fieldcraft) If you've got a reliable back-up, or don't mind paying for a rental on the day if it doesn't work, good luck (Good excuse to re-use an old pic)

They give you the connectors, and the two sets of signal wires (one single, one double) are both very long, but no heavy duty wire. I could butcher some of my existing tamiya leads etc to harvest some. I don't have any spade connectors so I'd have to splice onto the rather short bit of red wire coming off the motor... which just feels like another potential point of failure, but I guess it's what I'm left with. Ok. I have a plan of attack for tomorrow. Now I'm off to the pub!

I think I'd end up having to splice wires... basically I thought the simplified version with the single signal wire would be much easier to reverse (if I had to) than messing with the current wiring... and in fact the instructions mention the second option when replacing all the current wiring with a heavier gauge. However... it's not working. So I either reverse it and find a 7.4v battery that'll fit (having just requested an 11,1v nunchuck from Titan which won't fit, whereas the original 7.4v did, d'oh!) ... or I fix this. I'm not entirely sure I'm brave enough to strip off what's there.

Thanks Iceni, I'll consider what you have shown, but my method is as per the Gate instructions... https://www.gatee.eu/images/gate/instrukcje/merf32-en.pdf Section 2a, which specifically says the signal wire only carries a small current

In preparation for a couple of new 11.1v batteries arriving for my F2000 (already upgraded with full cylinder, hi torque motor, better spring), I've bought and installed a Gate Merf 3.2 I've taken the front (left) trigger wire and moved it to the connect at the rear contact, and installed the single signal wire to the now open contact. I've programmed the MOSFET for the 11.1v LiPo battery, but everything else is at the defaults. It fired. It fired full auto at 19rps. Nice'n'snappy And then it stopped. I took it all apart again. Put in the new piston which I'd already found has less of an airseal, but had the correct piston head to go with my new cylinder head. And then it fired again. And then it stopped. Recharged the battery (from 10% charge, 3.60v each cell, which didn't exactly scream 'battery voltage too low' to me) And then it fired again. And then it really jammed up. Might be my fault, maybe I didn't tighten up the screw enough but the piston head came away and broke the rack. I took it all apart again. Refitted the old piston. Radiused the gearbox shell too. And then it fired again. And then it stopped. It always fires with the programming trigger connected, but when I go back to the signal wire / gun trigger, it doesn't always fire again. The signal wire looks fine, no obvious pinches on it, the solder is secure. The fact it has sometimes fired again after a delay makes me think of a thermal cut-out, but everything has only got slightly warm after the few bursts I get to fire each time. I guess I'll re-solder the signal wire, but is there anything inside the trigger unit that might have gone awry too?

Quick update: Rate of fire up to 19rps. Obeying the '20 is plenty' rule, at least for the moment! Bad news: gun stopped pew-pewing again. It went for longer before stopping, but stop it did. No warning lights on the Merf, start-up lights showed it was still happy. Battery swap (to 7.4v) didn't fix it. The 11.1v battery is down to 10% (~3.60v per cell) so I'm re-charging it now, in case the Merf is very conservative with its battery protection. The odd thing is if I do the trick of connecting the programming trigger to the Merf, it'll fire quite happily. Maybe my signal wire is shorting after some vibration...?

I've fitted my Merf! Good news: full auto's like a beast, noticeable increase of RoF in my F2000 with the SHS hi-torque motor + 1200mAH 11.1v Turnigy Nano Cell 15-25C. Really snappy response in semi too. Bad news: it stopped firing after a few bursts. Connected a couple of 7.4v batteries and nothing doing there either. Tried them in the DE, worked. Gutted. But then I realised I hadn't set the battery type in the setup menu. Connected the programming trigger, changed to 11.1v LiPo in the settings, *bingo* back to shooting again. I've not really 'gone for it' since then, I'm setting it aside for the evening: I'd rather go to sleep with a working rifle than stay awake with a broken one I'll give it a workout tomorrow to see what's what. I'll chrono and get a RoF for it, if it's running well. Hopefully those 30C batteries will turn up soon, they'll be interesting

Further update, I have to commend Titan on their customer service again - they've let me pay the difference to upgrade from the 7.4.v stick to the 11.1v nunchuck. So as long as it doesn't die / I don't kill this one too, I'm well sorted for batteries! This means I'll have a variety of C-ratings to play with... I'll probably stick with the lower ones in the DE just because it has a stock motor, and leave the high stuff to the F2000.

Haha, I've actually used one of those! I was a member at Bedford shooting club and burned through a few boxes of ammo through a ruger 10/22 with one of those type of mags... Now I see what the gun inside that beautiful stock is, I'm totally on board now ?

And I'll annoy everyone by saying 'neither', it needs a short straight mag to make it look more like a hunter's gun rather than something military (which the stock assuredly isn't) But I get your saying 'less ugly', so the curved one for me. At a push.

Update, because Titan have just got in touch. Their engineer reckons 2 and a bit days of the battery left in my gun might have been enough to run it entirely flat to the point it couldn't recharge. Outside of the fact the DE MOSFET is supposed to cut power when it detects a low charge, and it had masses of charge left in after Saturday, and Li-ions aren't supposed to be vulnerable to that anyway, Titan have volunteered to send me another replacement! I can only be impressed with that sort of customer service It'll be a spare though, I've just ordered two 30c 11.1v Li-Pos from eBay, same ones as @Rogerborg ☺️

One description has the capacity at 28 and the other at 31. So it's not a silly or even straightforward question. I'd give them a call before ordering.

An interesting question, as they're obviously about holding the piston at opposite ends of the cylinder. So which takes preference? The Perun manual states: "While precocking is on, the AB setting becomes irrelevant. However, any programmed AB setting will be stored in memory and will become effective as soon as precocking is disabled." Link: https://perunairsoft.pl/hybridv2.pdf