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Gears and motor

Aux

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Hi all, 

Wanted to get some advice from experienced aeg owners about gear ratios. 

Basically im upgrading my motor from specna arms stock to xt high torque 22tpa, but im really stuck between 13:1 or 16:1 gears, as i want good trigger response but don’t want to stress the motor too much, especially when I’m running 7.4lipo.

What would be recommend for best trigger response? (Rof can be ignored, as i only use semi)
 

Sorry if this had already been asked, as i couldn’t find anything on this particular combination

 
Trigger response: 13:1 faster than 16:1.
 

Motor/battery stress: both will stress (13:1 will stress a bit more), but there is no practical difference.

 
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agreed as above, however why 7.4v? first upgrade (if not standard nowadays really!) should be using 11.1v. 

if anything I'd go 11.1 and a 22tpa motor with 18.1 gears. if you don't have a mosfet a simple perun inline mosfet will do the trick. 

 
agreed as above, however why 7.4v? first upgrade (if not standard nowadays really!) should be using 11.1v. 

if anything I'd go 11.1 and a 22tpa motor with 18.1 gears. if you don't have a mosfet a simple perun inline mosfet will do the trick. 
As i've heard 11.1v could burn out my x axr mosfet, strain the motor, gears more, and also just haven't bought one yet. 

 
anything can burn if not correctly installed; that said it should handle 11.1 with no issue (almost no point in a mosfet if it couldn't handle 11.1!)

strain on gears and motors is nothing crazy and very normal today; any shs gears will handle that easily for a looong time. 

 
13:1 for me.

Any 22tpa motor can pull pretty silly springs without any issues, pulling 13:1s at UK powers won't strain them in any way possible unless you get a lemon motor, but if you're buying from @ak2m4I'm sure he'll provide excellent service should anything happen.

For reference, at 0.99J a 22tpa + 13:1 setup powered by a 11.1v will produce around 30 rps and a VERY snappy semi, on 7.4v performance will be similar to a stock gun on 11.1 (so 20ish rps).

22tpa + 18:1 ratio is going to be painfully slow and it'll feel like you just wasted money.

Also your X-ASR will be fine.. It's not the greatest electronic unit out there, but it is "free" (read already included with the gun) so use it and replace with a better ETU once it breaks.

 
13:1 for me.

Any 22tpa motor can pull pretty silly springs without any issues, pulling 13:1s at UK powers won't strain them in any way possible unless you get a lemon motor, but if you're buying from @ak2m4I'm sure he'll provide excellent service should anything happen.

For reference, at 0.99J a 22tpa + 13:1 setup powered by a 11.1v will produce around 30 rps and a VERY snappy semi, on 7.4v performance will be similar to a stock gun on 11.1 (so 20ish rps).

22tpa + 18:1 ratio is going to be painfully slow and it'll feel like you just wasted money.

Also your X-ASR will be fine.. It's not the greatest electronic unit out there, but it is "free" (read already included with the gun) so use it and replace with a better ETU once it breaks.
Perfect thank you for your help mate. Parts arriving tomorrow hopefully all goes well.

anything can burn if not correctly installed; that said it should handle 11.1 with no issue (almost no point in a mosfet if it couldn't handle 11.1!)

strain on gears and motors is nothing crazy and very normal today; any shs gears will handle that easily for a looong time. 
yep okay, i've heard shs gears are quite durable just wanted to get a second opinion and now i won't be overthinking about the gears blowing up. 

 
Just make sure you get the pinion/bevel meshing right, as most of the gear noise comes from those two..

Having good meshing also ensures that the energy transfer from the motor to the rest of the gearset is as smooth and less violent as possible. At the same time do not shim the sector gear too high in an attempt to get the most contact surface between teeth, it's a common mistake that leads to the tappet plate rubbing and binding against the sector and that is bad for air seal and in general tappet plate longevity.

 
If you wanna improve the TR,easier way is use a faster motor and 11.1v battery especially semi prefer. After that you could consider change gear set cut gear/piston tooth and change a travel adjustable trigger. First part could achieve most of your target.

 
Just make sure you get the pinion/bevel meshing right, as most of the gear noise comes from those two..

Having good meshing also ensures that the energy transfer from the motor to the rest of the gearset is as smooth and less violent as possible. At the same time do not shim the sector gear too high in an attempt to get the most contact surface between teeth, it's a common mistake that leads to the tappet plate rubbing and binding against the sector and that is bad for air seal and in general tappet plate longevity.
Could you elaborate more on not shimming the sector gear too high? As in don't shim the tappet plate too close to the gearbox shell? If the tappet sits flat on the sector gear and not bend upwards is that a sign of good position?

If you wanna improve the TR,easier way is use a faster motor and 11.1v battery especially semi prefer. After that you could consider change gear set cut gear/piston tooth and change a travel adjustable trigger. First part could achieve most of your target.
Yep just ordered some new 11.1v.

 
Could you elaborate more on not shimming the sector gear too high?
When shimming the sector gear you will need to take into account what components it interacts with:

On one side you have the spur gear, on the other side you have the tappet plate and on top you have the piston rack.

Spur gear interaction is easy, shim the sector low enough to have a tiny gap between the upper flat side of the spur and lower flat side of the sector.

Rack is also easy, as most piston racks allow for plenty of movement anyway.

Tappet plate is where it gets tricky.

At first, have the gearbox with just the tappet plate installed, close it and check if the plate moves freely, if not the plate needs slight trimming.

Then open the gearbox, install the shimmed sector gear and close again with the tappet plate.

Tappet plate should be able to still move freely while the sector gear is in there, also try to rotate the sector gear as if it was actually cycling the piston and check for binding.

Should there be rubbing, you will need to lower the sector gear. I recommend using 0.15mm shims along with 0.1/0.2s because you get an extra level of adjustment.

 
When shimming the sector gear you will need to take into account what components it interacts with:

On one side you have the spur gear, on the other side you have the tappet plate and on top you have the piston rack.

Spur gear interaction is easy, shim the sector low enough to have a tiny gap between the upper flat side of the spur and lower flat side of the sector.

Rack is also easy, as most piston racks allow for plenty of movement anyway.

Tappet plate is where it gets tricky.

At first, have the gearbox with just the tappet plate installed, close it and check if the plate moves freely, if not the plate needs slight trimming.

Then open the gearbox, install the shimmed sector gear and close again with the tappet plate.

Tappet plate should be able to still move freely while the sector gear is in there, also try to rotate the sector gear as if it was actually cycling the piston and check for binding.

Should there be rubbing, you will need to lower the sector gear. I recommend using 0.15mm shims along with 0.1/0.2s because you get an extra level of adjustment.


Cheers, i think i've done it right, the gun currently sounds like this, is that somewhat a good shimming job?


IMG_1564.mov

 




Also i noticed my first shot after loading in mag doesn't fire anything the nozzle seems to be pushing forwards a little bit, could it be the cause of new piston?View attachment 147109

 
is that somewhat a good shimming job?
Phone mics for some reason like to enhance high pitch noises, but overall it looks like it's a little too tight.

 
Phone mics for some reason like to enhance high pitch noises, but overall it looks like it's a little too tight.
Cool thank you will give it a bit of adjust later.

In regards to the air nozzle sticking out is that normal?

 
As i've heard 11.1v could burn out my x axr mosfet


It doesn't burn out, it just bleeps-out and refuses to play at too high a current draw.  I've experienced it, someone else here has too (I forget who), but that's with 11.1V and a Big Dragon M160 brushed motor (meaty but not particularly efficient) in a 1.8J DMR build.  Worst case, you already have 7.4V so can fall back to that if you do experience it on a game day.  I wouldn't be put off going to 11.1V just because of the stock X-ASR.  The fact that it's there means you can replace it an actual fire control mosfet like a Warfet or Perun AB++ (or insert other mosfet of choice) with a bit of soldering.

 
It doesn't burn out, it just bleeps-out and refuses to play at too high a current draw.  I've experienced it, someone else here has too (I forget who), but that's with 11.1V and a Big Dragon M160 brushed motor (meaty but not particularly efficient) in a 1.8J DMR build.  Worst case, you already have 7.4V so can fall back to that if you do experience it on a game day.  I wouldn't be put off going to 11.1V just because of the stock X-ASR.  The fact that it's there means you can replace it an actual fire control mosfet like a Warfet or Perun AB++ (or insert other mosfet of choice) with a bit of soldering.
Yep @Colin Allenwas kind enough to send me a perun ab++, so should work fine wwith 11.1V batteries

 
Also i noticed my first shot after loading in mag doesn't fire anything the nozzle seems to be pushing forwards a little bit, could it be the cause of new piston?
Nah, piston has no part in this.

The nozzle resting position is set by the position of the sector gear after a shot, the position of the tappet cam, the dimensions and shape of the delayer if present and the shape of the tappet plate.

All my guns have the nozzle fully forward when in their resting positions, others have it fully retracted, most guns have it somewhere in between.

 
Nah, piston has no part in this.

The nozzle resting position is set by the position of the sector gear after a shot, the position of the tappet cam, the dimensions and shape of the delayer if present and the shape of the tappet plate.

All my guns have the nozzle fully forward when in their resting positions, others have it fully retracted, most guns have it somewhere in between.
i see it doesnt really affect functionality so i'll just stick with it

Bit of a bigger problem though is that I've noticed very fast heating of the motor, we talking about 35 to 40 shots of semi. I fitted my stock motor(14tpa) back in and it wasn't overheating, which is so weird cause surely the stronger motor would strain less? Any ideas whats causing it?

 
Any ideas whats causing it?
Very odd..

Do you happen to have an amp meter you could plug to check the power consumption?

My experience with 22tpa motors is limited to the good ol' ZCI one (bought from Pete when Brexit wasn't a thing) and it didn't pull more than 13 amps in full auto on a 7 tooth DSG. on 13:1s it pulled 12 amps and no sign of overheating even after full mags spammed in semi.

 
Very odd..

Do you happen to have an amp meter you could plug to check the power consumption?

My experience with 22tpa motors is limited to the good ol' ZCI one (bought from Pete when Brexit wasn't a thing) and it didn't pull more than 13 amps in full auto on a 7 tooth DSG. on 13:1s it pulled 12 amps and no sign of overheating even after full mags spammed in semi.
Unfortunately no, I've reached out to him and he offered for me to send it back so he can run some tests on it, i managed to lower the temperature of it by a 5 degrees though it still reaches around 75 degrees with 1 mag of quick semi.

The motor itself looks high quality and strong magnets too, im guessing it may be a defect in the motor or something else wrong with my setup, which i've spent the past few hours tying to figure out still came to 0 conclusion.

If ak2m4 finds no defect in the motor, worst scenario i'll just go back to my stock set up or take it to an airsoft store to get it fitted which I'd expect to be PRICEYY. Hopefully it's a motor problem.

 
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