Airsoft Smart Control Unit/upgrade issues

[Maethori]

NOTE: see bottom for recent changes

Soo... I like to teach myself things by doing them and that includes learning aegs by building a custom one out of mostly new parts and a few good used parts.

Now I put them together, briefly dry fired (yes I know this can break things, but I figured that doing it briefly on brand new parts wouldn't hurt...and I really wasn't in the mood for completely assembling the gun before testing if the gears/motor/electrical connections actually worked)

But whatever, my lack of knowledge aside...
This is the complete list of parts my gearbox and internals contain:


-systema reinforced gearbox with selector plate

-modify bore-up m16a2 cylinder set (including nozzle) (shortened the cylinder about 1mm because it was too long to fit in the gearbox properly)
Also, yes I do need the bore-up because I have a 650mm barrel.

-modify quantum piston

-modify enhanced tappet plate

-modify smooth torque-up gearset and anti-reversal latch

-CA stock cut-off lever

-KA low-resistance wiring and contacts combined with stock CA plastic parts that hold it together since KA plastic was crappy

-modify safety lever

-CA stock trigger

-modify sp120 spring

-modify v2 metal spring guide (with modified "end pins" because the original ones were too wide to catch the inside of the gearbox)

-Guarder Infinite Torque-up motor

-Intellect 9.6v batteries (1200 and 1600mah)


Okay... after putting this together I had several problems.

1. After every trigger pull and cycle the gears (likely pinion gear) made a grinding noise like one gear was still moving while everything else had stopped. It was much more pronounced on full auto. I cranked the motor height way up and it sounded much better on semi, but not really for auto.
EDIT: I should mention that the pinion gear looks a little bit battered, but I can't find anything else that looks battered, although it pretty much has to be rubbing against the bevel gear.

2. The 1200mah battery worked mostly when the wire extension with fuse was not connected. It didn't have enough power with the extension. The 1600mah worked either way, but only properly on full auto (which produced a much higher ROF than the 1200mah somehow...). It would work on semi about every 3 trigger pulls like it needed to build momentum to get that last bit of spring compressed. The 1200mah especially was heating up.

3. The piston head cracked...yes I know this could be a risk from dry firing, but I honestly did not do it for very long and no other gun I've played around with had any problems. Is there an aluminum head I can use for the bore-up cylinder? Will the Mask head with sorbo pads work at all?


I'm kinda lost as to what I did wrong here, so any help on any of the things mentioned would be great.

EDIT: Images of damaged parts

Previous poly piston head:


Motor pinion gear:


Thanks!


EDIT: This is now the current setup that is working better, but still not properly
I should mention that things sound fine now in terms of grinding, and there is no more over-cycling.

This is the complete list of parts my gearbox and internals contain:


-systema reinforced gearbox with selector plate (modified with 5x5mm larger notch as per ASCU installation instructions)

-Modify bore-up m16a2 cylinder set (including nozzle) (shortened the cylinder about 1mm because it was too long to fit in the gearbox properly)
This cylinder head now has a Sorbo pad

-Modify quantum piston

-Modify aluminum bore-up piston head

-Modify enhanced tappet plate

-Modify smooth torque-up modular gearset

-CA stock cut-off lever

-Airsoft Smart Control Unit with small connector changed to large

-CA stock trigger

-Modify sp120 spring

-Modify v2 metal spring guide (with modified "end pins" because the original ones were too wide to catch the inside of the gearbox)

-Guarder Infinite Torque-up motor

-Intellect 8.4v battery (5000mah)

[zone 69]

It maybe that its over cycleing and the grinding noise your hearing at the end of your cycle is the piston teeth sliping on the Sector gear. look for ware on the piston teeth and Sector gear to see if this is happening.

[coach]

Originally Posted by Maethori

Soo... I like to teach myself things by doing them and that includes learning aegs by building a custom one out of mostly new parts and a few good used parts.

Now I put them together, briefly dry fired (yes I know this can break things, but I figured that doing it briefly on brand new parts wouldn't hurt...and I really wasn't in the mood for completely assembling the gun before testing if the gears/motor/electrical connections actually worked)

But whatever, my lack of knowledge aside...
This is the complete list of parts my gearbox and internals contain:


-systema reinforced gearbox with selector plate

-modify bore-up m16a2 cylinder set (including nozzle) (shortened the cylinder about 1mm because it was too long to fit in the gearbox properly)
Also, yes I do need the bore-up because I have a 650mm barrel.

-modify quantum piston

-modify enhanced tappet plate

-modify smooth torque-up gearset and anti-reversal latch

-CA stock cut-off lever

-KA low-resistance wiring and contacts combined with stock CA plastic parts that hold it together since KA plastic was crappy

-modify safety lever

-CA stock trigger

-modify sp120 spring

-modify v2 metal spring guide (with modified "end pins" because the original ones were too wide to catch the inside of the gearbox)

-Guarder Infinite Torque-up motor

-Intellect 9.6v batteries (1200 and 1600mah)


Okay... after putting this together I had several problems.

1. After every trigger pull and cycle the gears (likely pinion gear) made a grinding noise like one gear was still moving while everything else had stopped. It was much more pronounced on full auto. I cranked the motor height way up and it sounded much better on semi, but not really for auto.

2. The 1200mah battery worked mostly when the wire extension with fuse was not connected. It didn't have enough power with the extension. The 1600mah worked either way, but only properly on full auto (which produced a much higher ROF than the 1200mah somehow...). It would work on semi about every 3 trigger pulls like it needed to build momentum to get that last bit of spring compressed. The 1200mah especially was heating up.

3. The piston head cracked...yes I know this could be a risk from dry firing, but I honestly did not do it for very long and no other gun I've played around with had any problems. Is there an aluminum head I can use for the bore-up cylinder? Will the Mask head with sorbo pads work at all?


I'm kinda lost as to what I did wrong here, so any help on any of the things mentioned would be great.

Thanks!

1. recheck your shimming. you may have the bevel gear out of position.
2. what connectors are you using? switch to deans if you haven't and then run the fuse if you must.
3. what piston head did you crack? adding a sorbo pad on both the piston and cylinder head would alleviate the problem. (remember to check sector gear to piston engagement and remove the first tooth as necessary)

[m102404]

Originally Posted by coachster

1. recheck your shimming. you may have the bevel gear out of position.
2. what connectors are you using? switch to deans if you haven't and then run the fuse if you must.
3. what piston head did you crack? adding a sorbo pad on both the piston and cylinder head would alleviate the problem. (remember to check sector gear to piston engagement and remove the first tooth as necessary)

remove the first tooth? I thought it was better to remove the 2nd tooth of the piston...

[cellulose]

I think the Modify Quantum Piston already has the second tooth removed.

Definitely check shimming though.

[coach]

Originally Posted by m102404

remove the first tooth? I thought it was better to remove the 2nd tooth of the piston...

maybe it's second. I always call it the first since the end one doesn't look the same as all the other 'teeth'.

a piston I pulled out of a poorly built box. of course I file mine down a lot cleaner.

[Maethori]

Originally Posted by zone 69

It maybe that its over cycleing and the grinding noise your hearing at the end of your cycle is the piston teeth sliping on the Sector gear. look for ware on the piston teeth and Sector gear to see if this is happening.

The teeth on both look fine to me, though the cylinder has titanium teeth which probably wouldn't show wear very easily. The pinion gear, however, does show some wear.

Originally Posted by coachster

1. recheck your shimming. you may have the bevel gear out of position.
2. what connectors are you using? switch to deans if you haven't and then run the fuse if you must.
3. what piston head did you crack? adding a sorbo pad on both the piston and cylinder head would alleviate the problem. (remember to check sector gear to piston engagement and remove the first tooth as necessary)

1. The shimming shouldn't be an issue since it's the Modify Smooth gearset which is one complete piece, preshimmed to interact as well as possible.
2. I'm using small. Does it really matter if I don't have the fuse?
3. I cracked the Modify bore-up piston head.

Originally Posted by aBseNtceLL

I think the Modify Quantum Piston already has the second tooth removed.

Definitely check shimming though.

That is correct, the Quantum Piston is sans-second tooth.
As for shimming, see above.

[coach]

Originally Posted by Maethori

2. I'm using small. Does it really matter if I don't have the fuse?

the resistance is from the connector. correct me if I'm wrong but if you have a wire extension, it has 2 pairs of small/mini connectors. the gun will run with one but not both sets of connectors leading me to believe that they are the culprit and creating resistance which sucks away usable power away from your motor.

what's the fuse rated for? 20A? the fuse won't add much resistance at all. negligible at best. short the fuse box by removing the fuse and connecting both ends together then try firing the gun. it should react the same as with the fuse.

[cellulose]

Damn, good parts you got then, I have the Modify modular high torque and love it...

Do you need the S120+ spring? That will probably give you about 450 - 470 fps, which in turn puts much more stress on the motor and such, I had the Modify S100+ and now the S90+ for CQB and both turned over without issue. I am assuming you do want the S120+ though as you have a 650mm barrel, but if you have another spring maybe give it a try.

[Maethori]

Originally Posted by coachster

the resistance is from the connector. correct me if I'm wrong but if you have a wire extension, it has 2 pairs of small/mini connectors. the gun will run with one but not both sets of connectors leading me to believe that they are the culprit and creating resistance which sucks away usable power away from your motor.

what's the fuse rated for? 20A? the fuse won't add much resistance at all. negligible at best. short the fuse box by removing the fuse and connecting both ends together then try firing the gun. it should react the same as with the fuse.

Thanks, so maybe I at least need to solder together my own wire with a fuse in the middle and only one connector at the end. That should then help with one of the problems.

[Maethori]

Originally Posted by aBseNtceLL

Damn, good parts you got then, I have the Modify modular high torque and love it...

Do you need the S120+ spring? That will probably give you about 450 - 470 fps, which in turn puts much more stress on the motor and such, I had the Modify S100+ and now the S90+ for CQB and both turned over without issue. I am assuming you do want the S120+ though as you have a 650mm barrel, but if you have another spring maybe give it a try.

Yea, as far as I've seen in research and previous advice the parts should all work fine...
The bore-up cylinder says (and so have other asc users) that it needs at least an S120 spring to push it. But yea, with the 650mm barrel I'd imagine I need the S120. However, as you say, it can't hurt to try a lower rated spring.

[Jugglez]

You'll need a bore-up piston head to replace the broken one, a standard piston head will just leak a ton of air since it's not wide enough for the bore-up cylinder.

Have you actually checked the sector gear engagement with the piston teeth? Removing some material off the third tooth as well is not unheard of.

Also another thing to try, put the compression parts and gearset in, leave the spring and spring guide out and close the 2 halves up, move the piston back and forth with your finger, make sure it can move freely without obstruction. Piston rails in the shell are sometimes a little beefy and causes the piston to jam.

You have access to any bigger/juicier batteries (like a Lipo) you can test with? I'm thinking these mini batteries are holding you back.

And +1 on switching to deans.

[Maethori]

Originally Posted by Jugglez

You'll need a bore-up piston head to replace the broken one, a standard piston head will just leak a ton of air since it's not wide enough for the bore-up cylinder.

Have you actually checked the sector gear engagement with the piston teeth? Removing some material off the third tooth as well is not unheard of.

Also another thing to try, put the compression parts and gearset in, leave the spring and spring guide out and close the 2 halves up, move the piston back and forth with your finger, make sure it can move freely without obstruction. Piston rails in the shell are sometimes a little beefy and causes the piston to jam.

You have access to any bigger/juicier batteries (like a Lipo) you can test with? I'm thinking these mini batteries are holding you back.

And +1 on switching to deans.

I tested the piston, and it seems to be fine. It looks like it jams up on the last two gears but I think that's just cause of it lying on its side and contacting the 'open' sides of the shell.

The piston rails seem to be just fine as well...
So any ideas so far as to why my piston head cracked?

I don't have anything more powerful than a 9.6v 1600mah NiMH at the moment, nor do I have enough connectors to turn it to deans, but I guess that means I'll have to place yet another order with you, Jugglez.

[Maethori]

So I am getting an aluminum piston head and sorbo pads. However, this will only make it harder for the head to break.
I still need to find ideas as to why the previous head would have cracked so soon if anyone has any.

Thanks!

[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.