Piston questions

[D.Smitty]

Try not to tear me apart too much with such a noob question.

I have a ICS M4 anniversary edition (you might have seen it in the for sale section) that isn't selling.  In typical Smitty logic, I'm thinking "It's not making me any money, so why don't I spend money on it?!"

I have it on good authority that the gears are carbon steel, plenty strong.  The problem is that I want to run a solid M130 spring (maybe a stronger one, later) in this gun, and there is something about this gearbox that makes it chew through piston teeth.  Dom tells me that there is something about the gun that makes the piston sit about 1mm farther away from the sector gear than it should be....split gearbox, go figure, right?

I'm looking for the strongest piston I can find, so I figured that systema was the way to go...until I find that I can't find a non-polycarb systema piston (if you can, send me a link, I'm asking for it).  Now, I have nothing against polycarb parts, as they are extremely strong for their weight.  I only want to fire this gun on semi-auto, though, so I don't care about anything that will reduce my ROF...I want a piston with carbon steel teeth.  Since I can't put a PTW piston in there, I'm not sure where that leaves me. 

In short, my problem is this:  I see pistons out there with "metal" teeth, but I don't recognize the brand names, so I don't know whether we are talking steel, aluminum, or China-monkey-metal. 

Is JBU a reputable brand?
http://www.airsoftatlanta.com/product_p/50654.htm

What about Matrix?
http://www.airsoftpost.com/product_info.php?products_id=30044

Or are you guys thinking that Systema will still get me the most strength with the polycarb?
http://www.airsoftgi.com/product_info.php?cPath=31_148&products_id=3135

What about the systema die-cast aluminum:
http://www.airsoftatlanta.com/product_p/77057.htm

[python575]

martix = NO

Never used it but ive great things about the system super core piston
http://www.nashvilleairsoft.com/index.php?page=shop.product_details&flypage=shop.flypage&product_id=1724&category_id=&manufacturer_id=&option=com_virtuemart&Itemid=37&vmcchk=1&Itemid=37  

[Vanquish]

Have you checked your AOE?  The reason I ask is because if it's tearing up plastic pistons now, and you put one with metal teeth in there, one of two things can happen.  Either you'll tear up the metal teeth on the piston and put a lot of strain on your gears and gearbox, or your gears will fail.  If something's not quite right with it now, putting a metal piston will likely make it worse.

I tried that JBU piston a while back, and I didn't like at all.  Just an FYI.

[D.Smitty]

Have you checked your AOE?  The reason I ask is because if it's tearing up plastic pistons now, and you put one with metal teeth in there, one of two things can happen.  Either you'll tear up the metal teeth on the piston and put a lot of strain on your gears and gearbox, or your gears will fail.  If something's not quite right with it now, putting a metal piston will likely make it worse.

I tried that JBU piston a while back, and I didn't like at all.  Just an FYI.

I actually don't know how to check the AOE.  I'm still an amateur when it comes to working on gearboxes, but I want to learn. 

I'd like to know why you didn't like that JBU piston.  Was it crap durability or too heavy for the internals to pull it right or something?

Dominum has worked on this gun of mine, and he pointed out the piston problem...He says that it's a problem with the low quality control of ICS that has the gears set just about 1mm farther away from the piston then they should be, even when shimmed and aligned perfectly.  I'm sure you know that such a problem would reduce the surface area of the piston teeth in contact with the gear teeth.  IF that is in fact the case (and I've got no reason to think differently at this point, but I will check the AOE once I learn how), then all you can do is either lower your spring power or up your durability, right?

[ATAT Armorer]

I have been running a G&P white polycarb piston in my SPR for about a year now.  It pulls an m150 on an 11.1 lipo and I have never had any problems, I recently opened up my gear box and the piston had minimal wear.

[slickridley]

I had one of these in my 140/150 power spring DMR's, never showed any signs of wear,
would recomend the Deep Fire Full Tooth Titanium Piston

http://www.redwolfairsoft.com/redwolf/airsoft/Accessories_AEG_Cylinders_Pistons_Deep_Fire_Titanium_Piston_V_2_Full_Teeth_Titanium.htm

otherwise
JBU = NO
MATRIX = NO
Systema = yeah that will work

[Dominum]

I like Slick's suggestion.

To clarify for those of you with tech experience, the problem is that the sector gear is not engaging the piston with the proper amount of surface area. Due to low QA at ICS, the split gearbox's top half is sitting slightly higher than it should be when everything is fully closed up. This is therefore causing the piston teeth and the sector gear's teeth to engage each other on a smaller amount of surface area than is usually the case (on the z axis [vertical]). Practically, this means that he needs the piston with the absolute strongest teeth possible, as the reduced surface area forces more wear on the tips of the piston teeth. The sector gear, however, shows no wear, while the aluminum teeth of the piston are worn off on the tips in exactly the manner indicative of this problem, and now no longer have enough surface area to cycle at all.

[slickridley]

This is therefore causing the piston teeth and the sector gear's teeth to engage each other on a smaller amount of surface area than is usually the case (on the z axis [vertical])

Maybe he should consider getting a helical gear set and a helical compatible piston? (haven't checked in awhile to see if they're even available)
might be hard to find, but it probably would increase the surface area of contact

[Dominum]

It would actually halve it, as most helical gear sets and pistons have half teeth.

[SteevoLS]

For the record, helical gears don't have helical pistons. The only teeth that are helical are those that mesh with the other gears.

[img width=700 height=500]http://www.airsoftgi.com/images/airsoft ... earset.jpg[/img]

[Dominum]

It would actually halve it, as most helical gear sets and pistons have half teeth.

[Dominum]

It would actually halve it, as most helical gear sets and pistons have half teeth.

For the record, helical gears don't have helical pistons. The only teeth that are helical are those that mesh with the other gears

You are correct in stating that the piston teeth for helical gear sets are not helical, and neither are the teeth that engage them on the sector gear, however, they normally are only half teeth as in this pic:
http://www.airsoftatlanta.com/PhotoGallery.asp?ProductCode=50655
Though the pic you found is one of the sets that aren't, those are always polycarb, so in any case a helical piston, gear(s), or both will do nothing to remedy the problem.