Airsoft Smart Control Unit/upgrade issues

[Maethori]

Originally Posted by m102404

Looks like a parts failure...plain and simple. It is entirely possible to stress the part by over tightening the piston head screw. Blue loctite and firmly snug is all that's needed.

Check the shimming...even though the set is "pre-shimmed" doesn't mean it can't be adjusted. Personally...I've never cared for the caged gear sets...I tried a set and they were noisy as crap. You can get bushings and just take the gears out and shim them yourself.

Motor height can be adjusted without the cylinder/spring/piston/etc... in it...just the gears and trigger/switch mech. Do up the mechbox and mount the grip/motor/motor cap. Set the height (quietest sound). This is just about as good as it'll ever get. You can run in your gears at the same time....hold for 30sec bursts...until you're thoroughly bored.

When you put the compression parts back in and test fire...if it's screechy under tension then you're left with A) live with it...B) reshim/try other gears/motor/etc...

To check piston fit put just the piston+head, cylinder head and cylinder (no gears or other stuff) into the mechbox and do it up tight. Use a rod to push the piston all the way back (put the rod into the nozzle). The piston should go back nice and smooth. You should be able to push it back forward (stick the rod into the hole where the spring guide would go)...again it should be resistance free. If it's binding...alter what needs to be altered to free it up.

So far as the battery/laggy-ness of your setup...it sounds like those little batteries aren't getting enough power to the motor to crank the MS120+ spring.
- that motor should be more than capable (don't keep trying until things get hot...it's not good for the magnets)
- the gear ratio should be ok
- wiring (of mechbox or batteries...or inbetween mechbox and battery) is iffy. You've got the switch+block, mechbox wiring harness, motor connectors, any connectors from the mechbox, any extensions (through stocks, etc...), the connectors there, the battery connectors and battery wire and any connections on the battery pack itself to look at.

I run a bigger battery...the mini pack 1200mah is too small...the 1600 mini is marginal. With small cells like that in a m120 gun it'll be stressed to work for very long...and if the batteries have seen some use they might not work at all.

So if it were my gun I'd just run new wiring and minimize any connections right to the lead that the battery will connect to.

Not a fan of aluminum piston heads. Sorbo pads...whatever floats your boat...make sure your angle of engagement looks good.

Thanks! That helps a lot.
I'm guessing the piston head crack was due to over-tightening... I did make it more than snug.

The wiring from switch block to motor and out of the mechbox is new, but the extension/fuse was old. I will fix that then by soldering my own with only one connection at the very end.

For the battery and moving the motor and spring, what would be the effective difference in its ability when using a 9.6v large capacity battery versus a 10.8v standard or whatever capacity? For these situations is it volts or amps that I want...?

Thank you very much!

[m102404]

I can't tell you how many stock extension wires I've had to redo on guy's guns...I've literally have a box of garbage wire from it.

For batteries...there's large (SubC cells)...mini (2/3A cells) and LiPo. Basically mini's are fine for M90/M100/?M110? guns...but they really don't have the legs for lots of use on a M120 gun. A large 8.4V 3000mah battery will have lots of power and should be able to turn over a M120 spring easy. A large 9.6V battery is a bit overkill and "spiffy!".

A 7.4V 2000-ish LiPo is mini sized but packs the power capacity like a large battery. A 11.1v 1100mah LiPo is a little small, but will crank a M110/M120 fine (it's just kind of hard on the battery). The little stock tube LiPo 11.1v 1100mah acts "like" a 8.4v 3000mah large battery.

So it comes down to the cell type and its capacity to provide the power that's needed. Use large cell packs where possible...great bang for buck. Otherwise...I'd be using a lipo...basically whatever would fit.

Don't know what gun/stock you're using....but if it's a full stock, try a large 8.4v 3300mah. In short...mini batteries suck for upgraded guns. If that's all your stock will take...change stocks....if that's all your PEQ will take, go to LiPo

Also...batteries are less effective with many cycles through them...if you're draining them fast and recharging, they just won't have the
"guts" like they used to when they were new.

[Maethori]

Hmmm, thanks once again.

The gun I'm building is an spr with full m16 stock, so it should be able to fit pretty much anything I throw at it within reason.

[Maethori]

So, further developments in this gun...

The switch block and related parts weren't working correctly (some of them didn't move when the gearbox was assembled, but worked fine when opened up) so I took the 'easy' way out and installed an ASCU.

The unit itself is working just fine. It beeps once when I connect a battery, etc. I also changed the ASCU connection to large instead of small to coincide with my large-type batteries' connections.

The new large-type 8.4v batteries I got are moving the spring perfectly. I tested with my previous mini 9.6v to test and it still doesn't cycle, so I've solved that problem thanks to all your sage advice (thanks!).

However, all I can get the gun to do is to cycle a few times before the ASCU stops it and beeps twice. It does this whether or not the whole thing is assembled (ie. gearbox, motor, and battery connected to wires, but motor not inserted into gearbox...dunno if the ASCU knows the difference).

NOTE: The gun does not fire switching from safe to semi. It only works after I've switched to auto, or from auto to semi.

Any ideas what this could mean? I would guess that it's not motor height, since it does it regardless of the motor. I would assume that the selector plate needs some altering or replacing. Could my modular gearset need to be disassembled and re-shimmed/turned into a set of regular gears?

[coach]

If you have installed it correctly, you need to check a couple things.

First try a large 9.6 or bigger. I'm using a 9.9 LiFe and no issues but my 9.6 mini nimh won't turn it even though an 8.4 large use to turn th box prior to ASCU install. (Using a G&P m120 complete box)

Next you may need to mod your selector and or selector plate. I had to install without the mid and rear pins which lowered the box a hair, because the nozzle was pitched up a degree or two with them in, causing the nozzle to retract and get stuck in the back of the hopup. Now with the box lower than normal, the selector switch does not engage semi for more than a single round unless I rotate the switch towards auto just a touch. When I find the time, I am going to make a new piece to replace the dial behind the switch that moves the selector plate. Re shape it so that when the switch is in semi, it will push the selector plate back more.

[Maethori]

Well my 8.4v 5000mah battery turns it just fine.

I modded the selector plate as per the ASCU instruction manual (cut off another 5x5mm section from the spring notch). Are there any selector plates and levers that work better for this (ie. push back farther) so I wouldn't have to create my own part?

[coach]

Originally Posted by Maethori

Well my 8.4v 5000mah battery turns it just fine.

I modded the selector plate as per the ASCU instruction manual (cut off another 5x5mm section from the spring notch). Are there any selector plates and levers that work better for this (ie. push back farther) so I wouldn't have to create my own part?

Nothing to do with the top that you cut out. That 5mm x 5mm section is to allow the cut off lever to move freely so that it can determine gear position and ultimately start and stop each cycles.

It is the lower section that is a problem for me which also sounds like your issue as well. For me it is mechbox position that has shifted the selector plate. At this time, I don't see a simple fix but will see how a custom part will go.

[Maethori]

Thanks for the info. I'd like to hear how that custom part works out.

However, it doesn't make a difference in gearbox functionality with it in or out of the receiver so the (main) problem cannot ultimately be anything to do with the movement of the selector plate and lever.

EDIT: I should also mention that things sound fine now in terms of grinding, and there is no more over cycling.

[coach]

so did the position of the lever help you with semi?

[audi_bhoy]

I'm having similar issue right now, installed an ASCU, I found that selector plate was too tight in the body, thus not moving properly with the selector. I'll have some grinding done this afternoon to see how it goes.

[Amos]

Check and see that your internal screws aren't tightened down too far, if you've over-tightened some stuff or used the wrong screw you can have a bit of the threads protrude from the other side and push into your selector plate.

[Maethori]

Originally Posted by coachster

so did the position of the lever help you with semi?

I can't really test at this point because the only thing that it will do (in or out of the receiver) is cycle two or three times, beep twice, and stop.

Originally Posted by Amos

Check and see that your internal screws aren't tightened down too far, if you've over-tightened some stuff or used the wrong screw you can have a bit of the threads protrude from the other side and push into your selector plate.

Checked the screws and they are fine (they were just snug and are systema screws from the gearbox which don't appear to be able to stick out).
However, I have noticed that the bearings are sticking out quite far. Maybe the modular gearset is over-shimmed for the systema gearbox, causing the selector plate to stick and the ASCU to not function properly (and then beep twice and stop)...?

[coach]

Originally Posted by Maethori

I can't really test at this point because the only thing that it will do (in or out of the receiver) is cycle two or three times, beep twice, and stop.

Are you 100% sure it's not beeping twice because of a low or under powered battery? Other things to look for if its not a power issue is either the motors too tight or it's shimmed too tight.

[Maethori]

Originally Posted by coachster

Are you 100% sure it's not beeping twice because of a low or under powered battery? Other things to look for if its not a power issue is either the motors too tight or it's shimmed too tight.

I will say that I'm 90% sure. I last charged my batteries for testing this gun about a bit over a week ago I think, which would let them drain. However, they are 5000mah and have barely been used since them. I will charge them up fully though and try again to see if it makes a difference. As for battery ability when fully charge I have no doubt that they are powerful enough.
EDIT: one of them is sounding deadish right now so I will definitely recharge and try again.

For the motor I'm going to say again that it does the same thing whether or not it is inserted into the mechbox (does the ASCU sense that there's no connected motor and stop for that too?). I did test all different positions of the motor plate screw and they all produce the same result.

For motor shimming... ...I honestly don't even know what that is. Where would a motor be shimmed? I know if G&P didn't shim it tightly, I certainly didn't.


I hope I'm not sounding like I'm trying to knock down every suggestion...just trying to work through this. Hopefully not, but maybe I'll just have to 'throw' this at a willing gun doc in the end.

[coach]

Ah. There you go. I missed it the first time you mentioned it. You cannot test the motor outside of the grip. It will turn, shut off and give a double beep since the micro lever switch controled by the cutoff switch senses movement and when it doesn't move will power down to prevent damage.

I just tested my AR with my 9.6 mini. Wouldn't cycle. Put it on the charger and it had a voltage of 9.x. Charged it up and it worked fine. Not as crispy as my 9.9 LiFe but close.

What spring do you have in there? An 8.4 might not be enough. I'll charge one of mine up tonight and check for you.