HIGH SPEED GEAR STRIPAGE (56k warning)
 

I have read threw a few of ROF setup threads but some of them did not finish completely, people just stop posting. In this thread, http://forums.airsoftmechanics.com/i...hp?topic=282.0 , short stroking was recommended but results were not given. I would like to know more about an alternative to short stroking. I am already using a 330-340FPS spring and would not like to loose much more FPS. I'm getting a good ROF but I would like more and I have now gone through a second set of gears in about 600 rounds. :o :-[ I have also seen a few thread on angle of engagement, http://www.airsoftforum.com/board/in...howtopic=97416 , but I don't understand this concept or how to apply it properly. PLEASE HELP!!

SP90 spring
type 2 cylinder
swiss cheesed piston (~15g w/ POM head)
Systema high speed motor
9.6v 2000mah
SW-Computer
6mm bushings

Currently the AEG shoots around 25rps but I would like 30+, 35rps would be ideal. How far can this be taken before I find myself in my MB, replacing gears and pistons not maintenance, every other month? Anybody, experienced with rof (low FPS) setups please, SCHOOL ME!

My sector gears and spur gears contacting teeth are starting to bend toward each other. In my last set the spur teeth look as if they were wiped side ways. The pictures are of my first set which looks to be a much worse result but caused by the same problems. This wear is another kind weird.

I checked out my bushings and gear axles and I don't see anything that stands out. I might not be good I seeing the problem though. If you see anything that look fishy, each picture of bushings has a number above it.

http://i24.photobucket.com/albums/c4...Picture108.jpg
http://i24.photobucket.com/albums/c4...Picture111.jpg
http://i24.photobucket.com/albums/c4...Picture113.jpg
http://i24.photobucket.com/albums/c4...Picture109.jpg
http://i24.photobucket.com/albums/c4...Picture110.jpg
1
http://i24.photobucket.com/albums/c4...Picture115.jpg
2
http://i24.photobucket.com/albums/c4...Picture116.jpg
3
http://i24.photobucket.com/albums/c4...Picture117.jpg
4
http://i24.photobucket.com/albums/c4...Picture119.jpg
5
http://i24.photobucket.com/albums/c4...Picture120.jpg
6
http://i24.photobucket.com/albums/c4...Picture121.jpg

sorry about some of the quality. I did this with what I have, a webcam.


I don't want to just trial an error my way through anymore sets of gears. If TM gears can't handle the load I'll have the use another set that cost 3x the price os TM. I'll use Prometheus high speed gears when things are sorted out but I can't replace those, to expensive.

Side note: will the high speed gears change the AoE since they have a different ratio/number of teeth? By how much?

PLEASE HELP!!!

mateba

It seems that you are using standard ratio gears.

You shoud use high speed gears.

In my m4 i use this setup

Sp 90
modify high speed gears
Motor G&P m 120 high speed
Modify piston
Modify piston head
Metal bushing

All that running on a 8.4volts 1100mah batt.

I dont know the BPS but i was matching up with my freind m4. he was running on a 9.6 v bat, Magnum motor, etc.

Use bearings, use a weaker spring and shim them properly this time.
I know you incorrectly shimmed them because only half of each tooth was stripped, you aren't giving the gears maximum contact. Though about what Phil just said, I don't know whether those are standard or high speed for sure.

You know that the higher the rate of fire, the higher the rate of wear, right? ;)

+1

Are TM gears compatible with King Arms bearings? I had issues with them and Systema bearings. I know the first set was off. The sector gear had too much side to side play and was too high off the spur gear. The second time around I thought I had it right. The SP90 spring is a 1J spring (330-340 pre-settled) if that too strong? I'll try TM gears again.

Not in 600 rounds time. Thats a little too fast. :eek:

your suppose to shim the gears to reduce the side to side play....
Stick those thin O metal rings between the gears and bearings so when u close the gearbox (without the entire upper cylinder set) with a few screws in theres no side to side play, and it can spin freely

You are running a ridiculously small/low voltage and amperage battery for a high speed setup. We have pretty similar spec though.

yes, i understand the concept of shimming. There was no to very little movement when I stopped shimming the second set. The first set needed work and I didn't double check myself. I assumed I had it right from when I did months ago.

Could there be a possibility that the bushings are bad? If there a way to check this other than looking and guessing?

Yes, usually it's the piston that gives out first. But was point out that he shimmed it incorrectly.

Shimming correctly is MORE than just the relationship between the gears and the mechbox, proper shimming also is the relationship between the gears themselves to make sure they get maximum tooth mesh but with enough clearance between the gears themselves.

Yes, I thought I had it pretty close I had one of the thinnest shims under my sector gear.

Anybody know about TM gears and bearings? King Arms bearings?

That damage is pretty severe, do you guys think it could be more than incorrect shimming?

Did u take out the top part of the gearbox (Cylinder/piston/spring/tapplet plate... those) Then put in 2-3 screws into the gearbox, stick your finger into cylinder hole and try spinning the gears? they should spin very freely.. yet have no side to side play.

If u want to get highspeed i dont think theres much difference in bearings

All gears should fit all bearings...

You shouldn't be using TM gears in a high-speed set up... You should look at a set of guarder, or Systema Helical High-speed (The systema would probably be your best bet, but I've never made a high-speed set up; so I don't have first-hand experience.)

When i was researching for my high speed setup i had to think abour the shimming and the wear ont the gears.

This is why i choose modify modular gear set.

No shimming and gears are in the perfect timming. As mentioned the piston was the first peice to break down. But i fired at least 10 000 rounds befor it happened.

the gears were showing no sign of wear, they are rock solid. And if you dont want to have to worry about shimming ther are perfect.

http://www.airsoftparts.ca/store2/in...roducts_id=690

and your right about the low power batt.

so using a 9.6v will give you what your looking for. (up to 30 BPS)

No, don't use a weaker spring. If you go with a weaker spring, the piston may not return to battery fast enough, causing the sector gear to crash in to the piston rack. Anything in the gear train can be destroyed at that point.

I also recommend using bearings and high speed gears.

Make note: stock gears (especially Tokyo Marui) will NOT fit in to ball bearing bushings - regardless of the brand of the bearings.

I ruined a set off Systema bearings with TM gears. They are not compatible. But I would like to know what brand others have put them in. I understand TM gears are not designed for upgraded gun but I don't want to tear up Promy gears due to a lack of knowledge. I knew this would be trial and error since their is no clear-cut concept to reliable high speed setups. You just diagnose the issue and react.

Bearing would make a difference, they cause much less resistance than bushings and I do intend on getting a MB with bearings but I wasn't ready at the moment. The difference can be 2-3 RPS. And, yes! I took out my compression assembly to spin the gears while I was shimming. How else would you shim?

Need help! And does anyone know if TM gears will fit in King Arms bearings?

See the post just before yours (last post on previous page). Like I said, NO brand of ball bearing bushings will fit on Marui gears. They also will not fit on G&P gears.

You'd pretty much have to get a quality aftermarket gear set if you want to use ball bearings. For the sake of durability and testing, you my want to go with a cheap gear set like Guarder gears till you get things sorted out before going with a quality gear set like Prometheus. At least the steel Guarder gears will be strong enough to last through testing and also show you if you it's the gears that are messed up or if your setup is incorrect elsewhere. If you still manage to strip a Guarder gear set, then there's something wrong with the setup.

Is there ANY wear on the first 3 contact teeth of the piston? Are there any scratch marks on the face of the piston? (by "face", I mean the flat surface that faces down towards the gears that shouldn't have any contact with the sector gear.)

All right I think I have made up my mind here.

KA 7mm or 8mm AK MB
do you know if they come with the bearing already set?

Guarder flat gears
High Speeds are +$2, should I risk the confound? I intend to use Prometheus high speed gears eventually.

G&P HP 3 metal tooth piston
it seems they have 3 or so pistons named the same (the picture show the white one but I got the blue last time.)

Shim Brand other that Systema?
not thin enough. Anyone use Deep Fire?

Anyone used or heard things about the HurricanE gears?


This sucks, I can't trust my MB and I don't want to buy another 6mm to just put bushings in it, so I can use TM gears, and then still want a 8mm later.

thanks for the advice

Yeah, those King Arms gearboxes come with the bearings.

For accurate installation of those bearings (and any bearing or bushing for that matter), I'd suggest contacting Airsoft Innovations and purchasing their Bushing Insertion Tool. It allows for perpendicular alignment of the bushing/bearing during installation and relieves all pressure off the fragile inner races of bearings.
http://www.airsoft-innovations.com/BushingPress.html

As for the Guarder gears, might as well pick up the high speed set. If your ultimate goal is on that path, you can help kill two birds with one stone by troubleshooting with the proper gear ratio.

the King Arms MB don't come with the bearing already in the shells?

Shoot! thats a huge pain. Thanks for the suggestions and advice. I think I will try to get a 8mm MB and some Guarder HS gears.

thanks

Why is it such an issue whether the bearings are already in the shells or not? They're not THAT difficult to install...

Shimming them, however, requires extreme precision. Shimming of bearings has to be very accurate compared to bushings. It's easy to get fooled on how well they're shimmed because the bearings rotate on their own.

Failure to shim bearings properly can cause them to explode... which would destroy everything else in your gearbox. :P

+1

I have a lot of shimming to do on my 10 years old RC car. Only .015 off and your bearing will generate a lot of heat, and the ball will crack.

You might want to spend at least 1 hour just shimming, to make sure you get the PERFECT setup.

Also, Bearing install can be easier. If you heat up the mechbox a bit with a heatgun, the hole gets looser. You must make sure the bearing is seated perfectly because if has more chances to be wrong since there is more space.

If you have an old set of gears, you can use them to install the bearings. Place then in the hole, the the whole assembly in place and tap gently on the opposite side of the gear to set it in place. Be carefull to stay alligned, or you will damage both the mechbox and the bearing.

11.1 lipo, deans connectors, bypass fuse, keep the systema turbo, take 4 teeth off front of the front of the sector gear in a set of Pheonix Super High Cycle gears, (redwolf has them in), use a dremel tool for that, Angel Chopayya (sp) piston, (good luck finding one), tougher spring, will have to just test and cut coils off if over any fps limits, and as for swiss cheesing pistons... Bah! It does nothing noticeable. Ive also not noticed any difference in swapping out piston heads for a lighter one. And that will melt your switch. Just to let you know...

If that doesnt put you over 30 rps, I will eat my hat.

edit: oh and yeah.... shimming is important too.... AND GEAR & CYLINDER GREASE. USE IT.
Hurricanes high speeds are good gears, as are Modify high speed ratios. But the Pheonix ones... they are great gears.

I wouldn't particularly recommend that method, as you'd be striking the inner race.

MadMax's bushing installation tool is the best solution I've seen to date as it contacts ONLY the outer casing.

1, I would rather not buy the tool
2, I have never done this
3, I having a really bad experience with airsoft right now and I second guessing my own abilities.

The shimming isn't the issue. I can get .025 stainless shims if its really necessary. I know just because I've got the gear it means I'll be fine. But I do have the patience.

If you have any advice I'll take it. A mentor in airsoft is priceless. In my area, there is not a single MB guru. I fend for myself, along with my one friend that has been at this for years, on the internet.

anyway, thanks I really appreciate you taking the time,
mateba

yeah, 12.5v (charged) batteries and $200US+ of internals sounds like something I want to venture into. Thanks for the advice though. :)

I know, right? It would be so awesome. you should mos def go for it.

Actually no, since most bearing are made a tiny bit smaller in the center than outside.

Plus, if there is NO shims, the gear side will be applying force to the outer of the bearing evenly.

Exactly my point... the inner race is smaller than the outside.

Last time I checked, the bottom axles of the sector gear and bevel gear didn't have a diameter greater than 8mm, and neither do the top axles of the spur gear and sector gear - so I don't see how the gear would bear any pressure on the OUTER casing...
By striking the gear's axle against the bearing, you're essentially transferring the force on to the bearing's inner race and relying on that force to press the entire bearing in? Great way to split the bearings...

You don't have to hammer down the gears the way they used to be... one at the time, you can take, say the bevel's large side and place all your bearings with it.

hey just wanted to add these links. It is a how to with nice pics: http://popularairsoft.com/stories/piston-short-stroking
http://www.interq.or.jp/tokyo/akishi...y/spt/sptg.htm


I'm going to be short stroking (grinding only though) because my male piston will probably have a premature engagement problem haha . deepfire full metal rack + modify gearset. I have to check the AOE angle and see what I'm going to grind down first.

If your mechbox is compatible (TM compatible, not a reinforced mechbox), look into a Modify high speed modular gear set. They're reinforced, perfectly shimmed, easy to install / maintain and run quieter than standard gears. I just wished they made a set that was compatible with reinforced mechboxes, then I'd have them in all my guns.