SystemA Turbo + 12V + bearings = helical hi speed gear crash!

[AnakChan]

Hi all,

I've been trying to get the above combo working for some time now and each time I've crashed my all helical hi speed gears. At first I thought I shimmed incorrectly but I've tried twice and the gears still get stripped.

Oiless bushings though work perfectly fine (which is what I've settled for now). I'm wondering if I've pushed my configuration to beyond the limits, or I've still shimmed incorrectly?

[mcguyver]

Think of how fast the bevel gear is turning (fastest) then spur (next fastest), then sector (slowest gear). Bearings may have some wobble to them at these kinds of speeds considering low reduction rate + high motor speed. That may be what causes your gears to get chewed up.

Bushings have no other parts to move or wobble, so tilting of your gears is not as likely to occur.

Shimming may or may not be an issue. Hard to say unless you see it in person.

yah, way to fast

I have heard of people having gear issues when trying to run guns this fast.
Some say its because the gears complete their rotation and start the next cycle before the spring has fully decompressed, thus having the piston slam into the gears instead of the cylinder.

could be shimming also. At speeds that high, shimming must be far more precise.

[AnakChan]

Good point...I didn't consider the wobble. Forgot to add that it fires fine for a few hundred rounds, but continuous firing for XX seconds (just for test, no one would be doing that in reality :-)) is when it crashes.

Thx! Gives me something new to look at!

[vatek]

Out of curiosity, what gun is this in?

[The Saint]

What spring are you using?

[vatek]

Well, his location is Japan so he's gotta be under 0.98J.

[joaz]

Using helical gears for a high speed setup is a very bad idea. Get a set of flat gears for your purposes.

[AnakChan]

It's M4A1, therefore ver2 box :-
- Angs 0.9J spring
- SystemA All Helical Hi Speed
- SystemA bushings (now)
- SystemA polycarbonate piston and head
- SystemA bearing spring guide
- SystemA Cylinder head and nozzle
- Prometheus Type D cylinder

[Gryphon]

You're running a TWELVE VOLT battery with HIGH SPEED gears and a 0.9J spring!?

Really, if you need to ask why things are breaking in your gun you probably shouldn't be doing upgrades. Frankly I'm surprised the gears are the only things that've stripped, but I doubt the piston is far behind.

I still think its the gears cycling faster then the spring can decompress.

[Mantelope]

If that was the case, I would expect the piston to break before the gears. Happened on my P90 with helical gears, broke the metal tooth of my Systema piston without so much as a ding on my gears.

[HaZarD SFD]

Is it kinda like this 11.1vMonster

UBER P90

[Gryphon]

I just don't understand why people don't realize AEGs have physical limitations. You can't stuff a 600 fps spring into a V2 gearbox and expect the shell to survive. You can't drive a low power spring at 2000 RPM and expect your internals to last. If rate of fire is of primary importance, that's what BV classics and the Piper's minigun are for.

[AnakChan]

Hi Gryphon, well I am new to airsoft so I don't know the physical/practical limitations, but I pick up the theory relatively fast. I just started getting into airsoft about 2 months ago - I can hear the words "go an enjoy the game first before tinkering with the components".

But by nature I like to tinker with parts, so that's a habit that's gonna be hard to break :-). Anyhow, whilst we're on the topic of physical/practical limitations, what would be the limitation? Say my goal is to achieve an ROF 30-40/sec. 10.8V? 9.6V?

TIA!