Change your gearbox over to 6mm or 7mm solid bushings and you won't need 8mm bearings.

How exactly would you go about changing one of the most expensive, robust CNC'ed gearboxes over to 6-7mm.....? Or do you know of some conversion process?.....

Forgot you were using a prowin :p

KANZEN BUSHINGS FOR YA>. $22USD..

http://cgi.ebay.com/Kanzen-Airsoft-8...171110002r4463


Found a better site but its in german lol..

http://translate.google.ca/translate...3Dn1g%26sa%3DX

I've used 3 sets of bearings, all 3 died within short order.

I read an article about SystemA's MOSFET circuits that are on the market, called a switch device or something, its US$45 on redwolfairsoft.com. And in the article SystemA admits that the Magnum motor has higher torque AND is faster than a turbo. Switching from a Turbo to a Magnum in my ICS made me go from 24rps to 27rps. Standard gears, 350fps spring.

8mm bushings....could get them custom machined on a lathe, or maybe buy some 8mm bearings and very carefully put JB weld in the crack where the bearings are visible. Is it possible to take apart 8mm bushings and using the outside piece (the one that is in contact with the mechbox) work it a bit and fit a 6mm bushing inside it? It would still be two pieces but no bearings at least.

The best set of gears on the market right now are CNC and made by RiotSC on AirsoftMechanics.com. A set runs $110 USD shipped I believe.

For solid 8mm bushings I would check out McMaster.com. ID will be 3mm, OD should be 8mm so you have to worry about how large the flange is on your gearbox (I would just pull out an old 8mm bearing and measure it with a caliper).

Also, sorry to tell you but your setup is going to be prone to failure no matter what you do running 12 volts on a Systema Turbo, especially at that extremely low FPS (which you probably short stroked at least 2 teeth). I would also make sure you buy a new pinion gear (Eagle Force), and fix the Turbo's huge design fault (how there's nothing isolating the + from the - besides a thin coating of anodization).

i don't mean to thread jack, but this is the second place i've heard people running 330-350 fps in there high speed setups. isn't that a bad thing? don't you want to return your piston to the cylinder head before the spur gear grabs it again?

please enlighten me.

Heh no worries :)

Humm interesting... They look like they have filled in the bearing protection covers to make the units filled out more with less gaps for faliors.

Humm.. Interesting... I'll take a look at teh broken one and see whats what. Not sure about fitting another inside the frame. Slight miss align and it could be really bad news lol.

Cheers will look in to those. Na its not short stroking only neded to remove the 2nd to last tooth and its running fine. Yea i've got new pinion gears here already for both. I'm trying a Modify one out curently and a Guarder Heat Treated one. Will see how they do. Humm didint know that about the anodizing contact flaw? Any pics diagrams to show this in more detail?

Mine seems to be returning fine, and its incredibly fast. If it wasnt returning right the back of the piston gets ripped off. I guess as mine hasnt done that, its probably ok with just the 2nd tooth removed.

Most people short stroke or lighten the piston so it gets to it's resting position before the gears are ready to pick it up again.

I've never seen any 8mm bushings, but if you still want to try bearings, the Kanzen Ceramics are quite possibly the best in the hobby world (R/C or airsoft):

http://www.wgcshop.com/pcart/shopper.php?itm=KZ-AEG8SY

These should be able to withstand whatever you throw at them, up to around 500fps.

Be careful how you shim bearings... they require much more precise shimming than bushings, and even if you feel like they're rotating properly with a bit of side-to-side play, it's still possible you still shimmed them too tight. I've had to fix a lot of improperly shimmed bearings. Bearings also have a natural tendency for side-to-side play, so you need to factor that in when you test side-to-side play distancing and go a bit wider than you normally would with bushings.

I've run bearings on the majority of my AEGs for years and never had a problem with them. Same goes for guns I've upgraded for people.

False information. Bearings are perfect for a high speed setup. Bushings build up more heat than bearings in a high speed setup due to the friction involved.

What bearings AREN'T good for, are high VELOCITY setups.

That doesn't sound right - full auto fire should actually have LESS current draw than single shot fire. Same idea as if you start your car engine from a standstill, it will require higher cold cranking power from your battery than if you were running it constantly - even if you didn't have an alternator installed.

Those are for a CA M249. It won't help the OP.

They don't carry the Kanzen "Synergie" ceramic 8mm - those are the better choice.

Well did the bearing go first? Or did the gears break first? :p
Because if the bearing went first, I don't think ANY gear could survive that!
And FYI, prometheus gears are just some of the best gears, systema PTW gears are "indestructible" ;)

Thanks Illusion! Yea i agree i havn't come accross any before either, did wonder if there was a reason for it or not. These ones you listed look far more robust than the PGC ones that came stock. The problem i have now is whre onearth to buy a single Bevel Prometheu gear from. Because they are high speed the pitch ratio needs to be right. On good terms with WGC may give them a mail and ask if they can help.

http://www.fire-support.co.uk/store/...idCategory=268

5Th down? = They the right ones? - KZ-PT-AEG-8S:

http://www.6mil.co.uk/product.aspx?id=17506

Humm.... Those Kanzeon ones seem to have different dimensions. the Omega ones are 3x8x2.5mm... The ceramics ate 3x8x4mm.... Will have to check depths and such. Illusion i know you havse used Pro-Wins before. Have you used These in one of the shells? I hav ehte Black Seccond version edition.

Yea i spent along time shimming these. Checking for side to side play etc. They ran smoothly within the gearbox with minimal but very slight play maybe less than 1/4 - 1/3mm. It seemed to flow well. I've put beraings on countless other upgrades before also.


I did wonder about that. Meal on metal....Even with grease. There is a reason cars use bearings lol because theygo at high speed. Imagine driving a car on bushings.... No thanks.

I was wating for someone to comment on that. I use the Watts up power meter for checking batteries and power draw over, along with oter areas, Helps find the ideal fuse for a setup too. I've always seen Full auto pulling several amps less than Semi. This is why loads of semi auto trigger pulls blows fuses because of power spikes. Any thoughts as to why? I think i'll have to re-look in to this.

However i did find out the gun was very power economical. Usually i factor in 1mAh = 1-1.5 shots of bb's.. This one appeared to be about 3.5 bb's per single mAh Must be the high speed and fluidity allowing that.

I'm still unsure which went first. If the bearing went i could see the gear alignment hammering its self agaist the other gear and that one failing, but also past experience with Systema Pinion gears would make me believe that would have failed.

So i'm unsure. Prometheus Gear, PGC 8mmBearing, or Systema Pinion Gear. 1 Tooth Mission on the Pinion, ALL Teath missing on the Prometheus Gear, and The Bearing was uterly Destroyed however it was semi localised to the bottom of the gearbox because the teath stripped on the gear which stopped things spreading up tothe top areas.

CNC Gears eh.... Meh this project is very experimental on the entire thing even if it can be pulled off. Its like an F1 car. Keep tring combinations and throwing mney at it untill you get the best result.

Think i'll have to give those Bearings a shot from WGC, Anyone know if you can buy single gears? I've seen some CA ones for the SR25 you can buy those separatly but i've not seen Prometheus ones separatly.

After each race they have to rebuild almost entirely the car's engines too lol. How was the trigger response with that setup?

hehe yea they do :) however :) when you design something like this, you design in a week point deliberatly. Then you know the 1 mainitinece part that will need sorting. Reduces change of part falior in other areas. Planned Ware. The respose was rediculously fast. Instant, fastest ive ever seen, tested. :) So yea prety good :)

Was just suggested tolook up Phoenix Gears.... They look very good. Metal Injection production, self shimming, the works and found 2 shops stocking them. They sure arnt cheap though lol! $96-$130 for the gears, hummm.

The Omega / Classic are not the same thing as the Ceramic / Synergie line. Do not confuse the two. The Ceramic / Synergie line is the one you're looking for

I got my own PGC gearbox when they first came out, so it was the 7mm version. At the time, I did not have access to Kanzen bearings, so I got the next best I could find: Prometheus. They held up well to the 425fps setup I had running through them.

IMHO, I think 1/4 - 1/3mm play is still too little for bearing use, as that is pretty much the combined amount of play of both sides of the bearings at each end of the axle. Don't forget that the inner race does move against the outer race. That level of play allows for smooth movement between the parts of the bearing - if it were made tight, it would have too much friction to move. Where 0.25 - 0.33mm of play is okay for bearings, I actually go up to 0.5mm of play for bearings. I once blew some bearings for going too close to 0.25 - 0.33mm.
... or that could've been from an extreme setup, but that's another story. :P

That was why I asked if you had any damage to your piston - even if you removed the 2nd tooth, your voltage is extremely high and your setup could still be catching some of the teeth. This would be one source of resistance. How many rounds have you put through the system?

Prometheus gears are not indestructible - just last week I did a repair on a gun with a somewhat similar situation, where the inner teeth of the Prometheus high speed bevel gear were completely stripped to sh!t. All 12 teeth were sheared off, with minimal damage to the spur gear. I couldn't figure out why at first, then I noticed the setup was used with a Prometheus MS120SP spring.
Systema engineers have a theory on what they call "accumulated energy", which is what occurs when you have too little torque running through a system through some imbalance, whether the battery is too high, or the spring is too strong, etc. Either way, the system is imbalanced. Typically, most users will experience this when upgrading to a 400fps spring and maintaining OEM or standard torque gear ratios. As the motor gets cranked to wind the piston, energy builds up in the motor - when the piston finally gets released, an extreme amount of energy has built up in the motor to the point where the sector gear is practically THROWN the rest of the way and reaches the point of reset long before the piston has returned to battery. The sector gear rotating at that speed combined with the piston slamming forward ends up in a violent head-on collision.
This problem is further exacerbated with high voltage batteries. Increasing voltage is never a good idea to solve ROF issues - you can only go so far before the system becomes imbalanced.

My theory on why the mechbox on my workbench had the stripped bevel gear was due to this "accumulated energy" - further inspection of the piston confirmed my theory, as at least half of the piston teeth were damaged from striking the sector gear as it returned to battery. The shock force of the sector gear resisting against the piston was sent back through the spur gear. The spur gear stopping while the motor was still turning the bevel gear resulted in another collision at the bevel/spur gear junction, which eventually caused all of those connecting teeth to strip.

Again... check your piston to see if there's any damage to it. Otherwise, try a lower voltage setup, or if you REALLY have to have that extreme ROF (and it sounds like you're really pushing for it), I'd highly recommend short-stroking your piston and sector gears. The setup you're running almost demands a short-stroke mod.

My experience with Phoenix gears were not so good... I snapped several teeth off the spur gear and to this day, do not know why. I also found them to be quite noisy.