V3 Tech help

[B.O.P. Hawk]

After a while of doing tune-ups and installing standard upgrades, a more difficult project finally caught up to me...

The problem: My gearbox shoots one burst (one trigger pull) in full auto before locking up, and zero shots on semi auto.

Diagnosis: It seems that there is not enough power going into the gears to pull back the piston. It fires the first burst, then clicks like it is trying to turn but can't, as if there were an M150 spring in it.

Parts and Information:
Magic Box Teflon cylinder
Bravo "mushroom" piston head
Bravo CNC Double o-ring cylinder head <EDIT
Prometheus o-ring air nozzle
M120 spring
AMP high torque motor
Modify Quantum gear set (Yes, double sector gear)
Echo 1 8mm V3 gearbox
Standard wires
Standard Teflon piston
Correct AoE and tooth removal
Very good Shim job
Piston moves freely in spring-less compression setup (no friction)
Perfect compression through the nozzle
properly lubed
proper Motor height
When I open the gearbox after a jam, the piston releases forward like it was pulled half an inch back.


Possible solutions:
I don't know what the resistance on my wires is, so I'm thinking that maybe a new low-resistance wire set would to the trick.
It could also be that the motor in it is 6 or more years old and does not have enough juice to pull an M120 with 9.6 volts. The stock (E1 strandard) motor has the same effect, as does a G&G HT motor.


Near as I can tell, this is a perfect gearbox setup for standard gears. I am looking for advice from experienced techs, perhaps who have dealt with a double sector gear. Thanks in advance.

[Spartanacus]

I'm guessing it's pre-engagement. Your sector gear is returning and grabbing your piston before it returns fully forward, locking it up. Your piston assembly needs to be very, very light as well as being short stroked to match the teeth on the dual sector. And your M120 is probably too weak as well. I imagine your FPS is in the mid 200s? Your tappet plate should also be trimmed down. And you'll probably need a new piston as I imagine the one in there is already getting chewed up.

[B.O.P. Hawk]

If I put an M130 spring in (or the spring spacer), there is not enough power to pull back in the first place. I'll try this again, as there have been a few modifications since I tried higher power.

The tappet plate is the Modify one that comes with the gear set, specially designed to work with the DSG.

The piston looks fine for now. What is involved in "short-stroking" it?


Please keep the ideas flowing. I really need help to conquer this one.


EDIT:
After doing some research on short stroking, found that it involves cutting down sector gear teeth, which doesn't make any sense in this case due to the sector gear being custom the way it is. I don't think cutting more teeth will help.

[B.O.P. Hawk]

I think I found the problem... I was wrong about the free movement of the piston without the spring. The gearbox is actually squishing the piston so that there is not enough room to move. I must have put too much pressure on it some time since I had it working the first time (<100 fps forced me to redo compression).

Any tips on how to get more lateral space on the piston track inside the GB shell?

[Payback]

Try a different piston for the easiest fix if that's possible. I know some pistons are slightly different.


Next option would be to get out the files and dremell and start shaving some metal off the track. I think i would take the empty shell and cylinder to a shop with cylinders, and see what ones fit with the box nice and tight.

[B.O.P. Hawk]

Next option would be to get out the files and dremell and start shaving some metal off the track. I think i would take the empty shell and cylinder to a shop with cylinders, and see what ones fit with the box nice and tight.

The closest shop is an hour from my house, which Is why I started out doing my own tech work. In order to get it to work, I would have to shave down both the shell and the piston tracks, which does not seem like a good idea (then again, neither was trying out a double sector gear project).

I'm thinking I'll put something in the shell that is slightly bigger than the body of the piston and slowly tighten the shell down to bend it back in to place. Any objections or caveats?

[spazzticsmurff]

The closest shop is an hour from my house, which Is why I started out doing my own tech work. In order to get it to work, I would have to shave down both the shell and the piston tracks, which does not seem like a good idea (then again, neither was trying out a double sector gear project).

I'm thinking I'll put something in the shell that is slightly bigger than the body of the piston and slowly tighten the shell down to bend it back in to place. Any objections or caveats?

first and probly the most important piece of info that I would like is: what is your goals/expectations/ and what kind of play you intend to use this platform for?

next, how much and what kind of research have you done on building and maintaining dsg systems? cause it doesn't sound like you haven't really done any.

putting something inside you gb and tightening it down to bend it out to make more room in it, is seriously asking for trouble.

lastly, I would like to know more about the piston. standard Teflon piston tells me nothing, plus im not sure I can recall any pistons that are actualy made out of Teflon. also, you list 2 diff piston heads.

[Spartanacus]

Wait, did you bend your gearbox? Like dented it somehow? Pictures would be worth a thousand words here.

[B.O.P. Hawk]

first and probly the most important piece of info that I would like is: what is your goals/expectations/ and what kind of play you intend to use this platform for?

Mostly just for fun and sneakiness in field play. The DSG is overkill, I know, but it's what I want to do.

next, how much and what kind of research have you done on building and maintaining dsg systems? cause it doesn't sound like you haven't really done any.

I've done a fair amount of research on the topic. Internet sources yielded from a few inquiries on Saint Google... From what I have seen on forums, I know most of what there is to know about a DSG... Anything you know that I should?

putting something inside you gb and tightening it down to bend it out to make more room in it, is seriously asking for trouble.

Thought so.
I can't think of anything else to do, still using this gearbox. This is the E1 8mm, which has the sturdy bearings. Both of my other V3s are 7mm, and all I have is bearings for those, which is highly unrecommended to begin with. I figured the 8mms were tough enough.

lastly, I would like to know more about the piston. standard Teflon piston tells me nothing, plus im not sure I can recall any pistons that are actualy made out of Teflon.

The regular pale/white piston you see in JGs, G&Gs, etc... I thought they were made of a type of Teflon... The AoE is corrected and a tooth and a half is shaved...

Wait, did you bend your gearbox? Like dented it somehow? Pictures would be worth a thousand words here.

The shell looks completely normal. The only thing is that the left side (top-down with the nozzle pointing away from me) of the piston section of the gb is pushed in from the cylinder about 1.5mm while the right is flush.

[spazzticsmurff]

first and probly the most important piece of info that I would like is: what is your goals/expectations/ and what kind of play you intend to use this platform for?

Mostly just for fun and sneakiness in field play. The DSG is overkill, I know, but it's what I want to do.

next, how much and what kind of research have you done on building and maintaining dsg systems? cause it doesn't sound like you haven't really done any.

I've done a fair amount of research on the topic. Internet sources yielded from a few inquiries on Saint Google... From what I have seen on forums, I know most of what there is to know about a DSG... Anything you know that I should?

putting something inside you gb and tightening it down to bend it out to make more room in it, is seriously asking for trouble.

Thought so.
I can't think of anything else to do, still using this gearbox. This is the E1 8mm, which has the sturdy bearings. Both of my other V3s are 7mm, and all I have is bearings for those, which is highly unrecommended to begin with. I figured the 8mms were tough enough.

lastly, I would like to know more about the piston. standard Teflon piston tells me nothing, plus im not sure I can recall any pistons that are actualy made out of Teflon.

The regular pale/white piston you see in JGs, G&Gs, etc... I thought they were made of a type of Teflon... The AoE is corrected and a tooth and a half is shaved...

Wait, did you bend your gearbox? Like dented it somehow? Pictures would be worth a thousand words here.

The shell looks completely normal. The only thing is that the left side (top-down with the nozzle pointing away from me) of the piston section of the gb is pushed in from the cylinder about 1.5mm while the right is flush.

ok, here I goes.
dsg is not made for sneakiness of play, but that is ok.

did you buy the whole quantum set or just the sector gear?

if you don't have the spring guide spacer, then the m120 that you are using is entirely unsuitable for your build.

the white stock piston is also unsuitable for use with a dsg system. you need to have a piston with at least 1 metal tooth at your release side of the piston with all teeth after that removed. the piston should also be swiss cheesed to further lighten it, which will help with piston return times and lessen the risk of pre-engagement.

im willing to bet your wires are not the issue. your motor might be though. you sad you motor might be 6 or more years old, which means that most likely it does not have neo magnets, just like the other 2 motors you have tried.
if you do not have a neo magnet HIGH TORQUE motor to use for this build, then find one.

personally, I dont think you know as much as you think you now about dsg systems. that is probly not entirely your fault, you probly found some thread on some forum somewhere where some guy sounded like he knew all about dsg's, but he didn't know as much as he thought he did either. I would like to help you build a successful dsg, (even though you have chosen to use the inferior modify one) please pm me so that I can give you my number. there is more that you need to know and I would rather talk than type the amount of info required.

[Spartanacus]

We're all here to learn Spazz. I'm sure you're not intending to talk down to Hawk but it's coming across as such. That being said you are right on the neo motor. That is ideal, but not required for a dsg build. I'm more concerned about the gearbox being damaged. If it's preventing the pistonfrom moving freely, nothing else matters at this point. That is the first thing that needs to be addressed.

[spazzticsmurff]

We're all here to learn Spazz. I'm sure you're not intending to talk down to Hawk but it's coming across as such. That being said you are right on the neo motor. That is ideal, but not required for a dsg build. I'm more concerned about the gearbox being damaged. If it's preventing the piston from moving freely, nothing else matters at this point. That is the first thing that needs to be addressed.

I am, a lil bit. but when you say that you have done your research and that you know most there is to know about building a dsg and its apparent that you don't, its got to be expected just a lil bit.
that being said. I would like to see hawk get this system up and running properly and gain the proper knowlage to build another with out help.

it does sound like the gb is a lil bit off and if it is you will need to replace that gb with another. for a dsg to work properly, every part has to work just right. if there is any binding or anything not moving smoothly you will have a grip of problems.
don't worry abut the 7mm bearings in your other v3 gb's, just replace them with some high quality bushings. they are better than bearings anyways for a dsg, I don't even use bearings in any of my builds.

spartanacus: I have to disagree about the motor. its not just ideal, with the stress that the motor is under, a ferrite magnet motor will not survive for long. and I don't recommend neo mag high speed motors either, they will get hot in a hurry with a dsg.

hawk: I am also curious as to how you corrected the aoe and how you shimmed the gb. but that would probly be easier to talk about over the phone than type. ill pm you with my number.

[B.O.P. Hawk]

I came to this forum to be talked down to by someone who knows what they are doing so that I may learn to do it right, by myself, as he said. This is exactly what I came here for, don't worry about it... At least for me.


For the record... I dubbed it more economic to buy a full reinforced/partially CNCd dsg set that comes with a reinforced specialized tappet plate (yatta yatta yatta) from Modify for $60 than to buy a single sector gear only (as vastly superior as it may be) from Siegetek for $90. I got the quantum set.


AoE corrected with a Bravo "mushroom" piston and a 1/8'' sorbo, then measured the two teeth that needed to be shaved. It's super quiet, which is awesome... too bad it only fires once.

@spazz
I'll get back to you some time before LoW VI, whenever I have time. I'm going to go ahead and set it up with another gearbox and see where that takes me. I'll look in to drilling holes in my piston, as well as those motors.

Thanks for what you've given me so far. It's nice to see a thread with nice person advice on this forum.

[B.O.P. Hawk]

A bit of a necro-post for an update to this.

So, I got it working with the tienly 35,000 motor, a Swiss-cheesed bravo piston, an m110 with the 3cm spring spacer (pain in the butt to install), and a new GB shell. It worked great for the CQB field I was playing at, firming at about 35-38 rps at ~270 fps with a max effective range of about 75 feet. Maybe some day when I have the money and time to push the fps up to 350 or so (which would require a new stronger GB, and a lipo with deans) I will set it up again. For now, I have it built so that I'm getting 410 fps at 18-20 rps with about 150 feet of range. the DSG just isn't good for field play.

I am proud of myself for getting the system to work, and I learned a lot in this exploit. Thanks a lot to spazzticsmurff and Spartanacus for helping me out with this. I have a good working knowledge of a DSG system and of gearbox nuances in general, to include neo motors. Thanks again.

[ClownBaby]

Good job!

Acceptable necro

How bout a pic?