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MaciekA · January 1st, 2013, 10:43

Realistically, you yourself will be the judge of when you're "ready to go". Upgrading to powerful batteries will take you on some twists and turns and possibly a failure or two until you've stabilized your setup... At some point you will be at a game and realize your WE M4 has fired X number of rounds over N number of games and survived without failing. That's when you can put your seal of approval on it.

There are probably several dozen unique ways for your gearbox to fail due to using an 11.1V battery and MOSFET. This combination will deliver a lot of power to your motor, basically all the power that it can possibly ask for. Depending on the failure about to happen, it sometimes depends how many Amps your battery is able to put out during a runaway trigger (or short circuit) scenario or longer full auto bursts. If your motor is a strong neodymium motor and you have a battery capable of >100A of output, be prepared to get good at cleaning small shattered bits of parts out of your gearbox

Some likely "11.1V failure" weak points in your gearbox off the top of my head:

- Piston pickup tooth (or other teeth) getting sheared, collapsing, or otherwise failing due to full auto. Fixed with a stronger piston and AoE correction. You're unlikely to get the other common piston problem, pre-engagement, since I believe you're running your WE at >400fps right now without speed gears.
- Feeding problems caused by weak tappet plate spring (or other slow tappet movement issues) and/or caused by lack of sector delayer. Mashed BBs and jams, double feeding, lost compression issues, etc, can all happen due to this.
- Assorted failures in and around the piston itself. Shattered piston heads due to lack of loctite/threadlock, shattered plastic spring guides, shattered plastic cylinder heads.
- Sector gear losing teeth due to lack of AoE or weak metals.
- Pinion gear / bevel gear failures due to less-than-perfect pinion-to-bevel alignment and or shimming.
- Gear shaft failures due to weak metals.
- Anti reversal latch shaft or tooth failure due to weak metal (it's crazy how often I see this one, even with high end gearboxes!).
- Bearing failure. I just destroyed an 8mm G&P bearing a couple weeks ago during routine maintenance and testing. Inspect the race and bearings on your bearing bushings and make sure you can spot the signs that one has gone wobbly or failed on you. They seem indestructible at first but you can break one merely with the force of your hands if you know how.

What I recommend doing is just diving in and doing a few basic initial upgrades to jumpstart your project. Get your MOSFET installed (grab the GDS-4005, it's small and easy to install) and try running it with 9.6V and 7.4V batteries, just to make sure you've got the MOSFET installed correctly.

AoE: This is the biggest impact upgrade you need to do yourself that doesn't just involve throwing upgrade parts into your gearbox. When you're done with the MOSFET, the first thing to do is try to improve the survivability of your piston during high RoF fire through AoE. I recommend reading everything you can about adjusting AoE (angle of engagement) and fine-tuning your shimming (search around for pinion-to-bevel shimming or adjustment).

To summarize, you will want to make sure that your sector gear pickup tooth meets the piston pickup tooth to maximize contact surface area to spread out the force of collision and to minimize stress. During high-RoF fire, these two teeth come together with a strong force at a high speed, so if they don't come together "flat-face-to-flat-face", it is likely that one tooth will destroy the other over a short period of time. Plastic or nylon teeth get ground down or sheared off. Stronger metal teeth will usually have a sudden catastrophic failure and crack off. It can be prevented.

Here is a good picture I randomly found on Google that describes the type of failure I'm talking about:

Here's a random picture of angle of engagement between the sector and piston:

As you can see from this picture, there is an angle at which the pickup tooth of the sector can meet the pickup tooth of the piston. The setup in the picture is not ideal -- for example, it's pretty clear that the second and third tooth on the piston will have to be cut in order to accomodate the arrival of the sector gear's pickup tooth, like this:

I've drawn some dashed lines here to show what you would shave down with a Dremel tool in the pictured setup. Your setup might vary once you apply adjustment with sorbo...

Which brings me to the actual "AoE" part!:

This is somewhat down to experience and very fine details, but the angle of engagement in this picture is actually not good (good for illustration though). Let's extend some of the lines to see the angles and see why:

When these two teeth come into contact, the contact surface will more closely resemble a 1 dimensional line than a 2 dimensional plane -- a good way to aggravate any weaknesses in the piston, but also a bad way to transmit the torque of your motor to your piston. This is a very common failure point with high voltage batteries. The way you fix this angle is to move the piston back a very small amount. Usually all you have to do is install a 3/16" sorbo pad on your cylinder head and you're good to go. Often times, depending on the power of your setup, you will also want to upgrade your piston to one that is stronger. Some pistons can't handle high RoF at 400fps and above no matter how well your angle of engagement is adjusted. I recommend destroying your stock piston or any cheapies you have lying around (as a learning experience) before you throw down cash for a fancy Lonex red (or whatever).

So that's AoE.

Aside from AoE and a MOSFET installation (two tasks which will keep you more than busy enough), I would actually carefully not touch anything else in the system right now. That way if something goes wrong you have a good idea of what caused it, and you'll only be addressing one problem at a time.

I will add though that it might be useful for future purposes to determine if your motor is a neo motor vs. ferrite motor. Try checking to see if it sticks to your fridge or a steel locker door. If it does, you've got a neo motor, which is what you always want. (edit: an exceptional neo motor will attract every damned tool on your entire desk to it the instant you take it out of your motor grip.. arghh!! if you have one of these, pick up the habit of placing it in a magnet "safe zone" away from your work space every time you take it out)

January 1st, 2013, 10:43	#4
MaciekA Trader rating Join Date: Jun 2011 Location: Portland, Oregon, USA	Realistically, you yourself will be the judge of when you're "ready to go". Upgrading to powerful batteries will take you on some twists and turns and possibly a failure or two until you've stabilized your setup... At some point you will be at a game and realize your WE M4 has fired X number of rounds over N number of games and survived without failing. That's when you can put your seal of approval on it. There are probably several dozen unique ways for your gearbox to fail due to using an 11.1V battery and MOSFET. This combination will deliver a lot of power to your motor, basically all the power that it can possibly ask for. Depending on the failure about to happen, it sometimes depends how many Amps your battery is able to put out during a runaway trigger (or short circuit) scenario or longer full auto bursts. If your motor is a strong neodymium motor and you have a battery capable of >100A of output, be prepared to get good at cleaning small shattered bits of parts out of your gearbox Some likely "11.1V failure" weak points in your gearbox off the top of my head: - Piston pickup tooth (or other teeth) getting sheared, collapsing, or otherwise failing due to full auto. Fixed with a stronger piston and AoE correction. You're unlikely to get the other common piston problem, pre-engagement, since I believe you're running your WE at >400fps right now without speed gears. - Feeding problems caused by weak tappet plate spring (or other slow tappet movement issues) and/or caused by lack of sector delayer. Mashed BBs and jams, double feeding, lost compression issues, etc, can all happen due to this. - Assorted failures in and around the piston itself. Shattered piston heads due to lack of loctite/threadlock, shattered plastic spring guides, shattered plastic cylinder heads. - Sector gear losing teeth due to lack of AoE or weak metals. - Pinion gear / bevel gear failures due to less-than-perfect pinion-to-bevel alignment and or shimming. - Gear shaft failures due to weak metals. - Anti reversal latch shaft or tooth failure due to weak metal (it's crazy how often I see this one, even with high end gearboxes!). - Bearing failure. I just destroyed an 8mm G&P bearing a couple weeks ago during routine maintenance and testing. Inspect the race and bearings on your bearing bushings and make sure you can spot the signs that one has gone wobbly or failed on you. They seem indestructible at first but you can break one merely with the force of your hands if you know how. What I recommend doing is just diving in and doing a few basic initial upgrades to jumpstart your project. Get your MOSFET installed (grab the GDS-4005, it's small and easy to install) and try running it with 9.6V and 7.4V batteries, just to make sure you've got the MOSFET installed correctly. AoE: This is the biggest impact upgrade you need to do yourself that doesn't just involve throwing upgrade parts into your gearbox. When you're done with the MOSFET, the first thing to do is try to improve the survivability of your piston during high RoF fire through AoE. I recommend reading everything you can about adjusting AoE (angle of engagement) and fine-tuning your shimming (search around for pinion-to-bevel shimming or adjustment). To summarize, you will want to make sure that your sector gear pickup tooth meets the piston pickup tooth to maximize contact surface area to spread out the force of collision and to minimize stress. During high-RoF fire, these two teeth come together with a strong force at a high speed, so if they don't come together "flat-face-to-flat-face", it is likely that one tooth will destroy the other over a short period of time. Plastic or nylon teeth get ground down or sheared off. Stronger metal teeth will usually have a sudden catastrophic failure and crack off. It can be prevented. Here is a good picture I randomly found on Google that describes the type of failure I'm talking about: Here's a random picture of angle of engagement between the sector and piston: As you can see from this picture, there is an angle at which the pickup tooth of the sector can meet the pickup tooth of the piston. The setup in the picture is not ideal -- for example, it's pretty clear that the second and third tooth on the piston will have to be cut in order to accomodate the arrival of the sector gear's pickup tooth, like this: I've drawn some dashed lines here to show what you would shave down with a Dremel tool in the pictured setup. Your setup might vary once you apply adjustment with sorbo... Which brings me to the actual "AoE" part!: This is somewhat down to experience and very fine details, but the angle of engagement in this picture is actually not good (good for illustration though). Let's extend some of the lines to see the angles and see why: When these two teeth come into contact, the contact surface will more closely resemble a 1 dimensional line than a 2 dimensional plane -- a good way to aggravate any weaknesses in the piston, but also a bad way to transmit the torque of your motor to your piston. This is a very common failure point with high voltage batteries. The way you fix this angle is to move the piston back a very small amount. Usually all you have to do is install a 3/16" sorbo pad on your cylinder head and you're good to go. Often times, depending on the power of your setup, you will also want to upgrade your piston to one that is stronger. Some pistons can't handle high RoF at 400fps and above no matter how well your angle of engagement is adjusted. I recommend destroying your stock piston or any cheapies you have lying around (as a learning experience) before you throw down cash for a fancy Lonex red (or whatever). So that's AoE. Aside from AoE and a MOSFET installation (two tasks which will keep you more than busy enough), I would actually carefully not touch anything else in the system right now. That way if something goes wrong you have a good idea of what caused it, and you'll only be addressing one problem at a time. I will add though that it might be useful for future purposes to determine if your motor is a neo motor vs. ferrite motor. Try checking to see if it sticks to your fridge or a steel locker door. If it does, you've got a neo motor, which is what you always want. (edit: an exceptional neo motor will attract every damned tool on your entire desk to it the instant you take it out of your motor grip.. arghh!! if you have one of these, pick up the habit of placing it in a magnet "safe zone" away from your work space every time you take it out) __________________ "Mah check" Now you know Last edited by MaciekA; January 1st, 2013 at 10:49..