Replacement Parts for V1N Gearbox

[JLiang]

Hey guys,

I was doing range testing with my FAMAS today and I got my first catastrophic gearbox failure, which basically consisted of the piston head snapping off the piston, shattering itself, subsequently damaging the cylinder and the piston.

So, I'm on the hunt for aftermarket parts. However, with so many different companies offering different parts, I'm unsure of which to buy.

Cost is not an issue, but I don't want to pay more to get the same performance out of a cheaper part (if that makes sense). I don't care about brand names; if it works, I'm happy.

In case you're wondering, my gearbox is CYMA's V1N (Version 1, New Type) which has a mismatch of V2, 3, and 7 parts to help modernize the antiquated V1 GB. The cylinder is a Type 0 (I think; it has no holes and it's about 74mm long), the Piston and Piston Head are universal parts (I hope), and the Cylinder Head is a V7.

I was wondering if you guys with more internal expertise could recommend me parts.

Thanks in advance!

[JLiang]

As an additional note, is airsofparts.ca a veritable site?

I may get flaming for that, but I'm not sure.

:sheepishface:

[Forever_kaos]

When in doubt, check the review section on retailers:
http://www.airsoftcanada.com/showthread.php?t=123187

[JLiang]

Oh, thanks. Sorry about that.

As of right now, my parts list consists of the following:

Modify Enhanced Cylinder (450mm-590mm)
Sorbo Pad for V6/V7 Cylinder Head - 2pc
Modify Aluminum Bearing Piston Head
Modify Ultra High Speed Piston - New Version
Modify Rotary V3 Spring Guide
Modify Stainless Steel Shims

Any inconsistencies in the above? Any parts to avoid? To add?

Sorry about all the questions, I just want to be educated with my buys.

All are from Airsoftparts.ca.

[Freeze]

According to what I've read on ASC, I gather that Promethus (or something like that) brand parts are the best and longest lasting parts that money can buy.

By best that money can buy, I mean like $45 for a piston.

http://www.redwolfairsoft.com/redwol...eus_Piston.htm

[wind_comm]

maybe you should have a tech look it over and see what's salvageable.

also, you could spend all that money, or you could ask a tech in the know for some really great SHS parts.

[Boyso]

http://www.wgcshop.com/wgc2008/main/...atid=72&cat=28

You can buy original TM parts here.

[JLiang]

I don't need TM Parts because it's a Cyma. Thanks, though; that link looks promising.

My Asian parents are those kind of 'do it yourself or don't do it' kind of people, so getting it to a guntech may not be possible. I do know, however, that the piston head is gone, the cylinder has scratches that may damage orings, and the piston itself has scratches everywhere. The cylinder head is okay, though.

Um, $45 for a piston? I know that what I pay is what I get, but that's slightly overboard in my mind.

Thanks for all the quick replies, though.

[MaciekA]

Originally Posted by wind_comm

maybe you should have a tech look it over and see what's salvageable.

also, you could spend all that money, or you could ask a tech in the know for some really great SHS parts.

+1, don't spend money until you know for sure what is really necessary.

I'm really interested in seeing how you damaged both a piston and cylinder head at the same time (perhaps both were quite fragile?). Is there any chance you could post some pics?

[MaciekA]

Originally Posted by JLiang

I don't need TM Parts because it's a Cyma. Thanks, though; that link looks promising.

My Asian parents are those kind of 'do it yourself or don't do it' kind of people, so getting it to a guntech may not be possible. I do know, however, that the piston head is gone, the cylinder has scratches that may damage orings, and the piston itself has scratches everywhere. The cylinder head is okay, though.

Um, $45 for a piston? I know that what I pay is what I get, but that's slightly overboard in my mind.

Thanks for all the quick replies, though.

Your do-it-yourself attitude is going to work out really well as long as you have some time and/or cash to kill. In my experience, you will make a few mistakes on parts and fitment, but don't let this discourage you. In the end it WILL be worth the trouble of having attained the knowledge yourself on how to do these things. Every gun doctor starts somewhere. Might as well get your hands dirty.

Post some pics if you can... I'm personally really fuzzy on a V1 mechbox but am interesting in seeing what you're dealing with.

[JLiang]

Thanks. First encouraging words I've heard since this happened. :P

Okay, pics.

Basically, these parts



came off of this piston head



Scratching this piston (no, that's not lube)



Because that screw



stripped. I'll get Cylinder and more detailed pictures in a sec.

[wind_comm]

k, your piston/piston head is toast for sure.

[MaciekA]

Originally Posted by JLiang

Thanks. First encouraging words I've heard since this happened. :P

Ha, nice. You should see me when I break a gun these days, usually the first words out of my mouth are "oh boy, I can't wait to open this up".

Originally Posted by JLiang

Okay, pics.

Were you by any chance running the mechbox at a really high RoF on a LiPo battery or anything like that? I had a similar failure in my Diablo:



Basically the same thing happened to me as you, except for a slightly different reason. In my case, the screw came undone because I had failed to thread-lock the screw after completing the build and gaming it. After a few thousand rounds at 33rps, it finally worked its way out and wham.

From what I have read about the Famas mechbox, you should be okay using any v2 piston and piston head. You should google around to make sure. For the cylinder head, things might be a bit more tricky, so if you can salvage what you have, stick with it, because it's already matched to your air seal nozzle.

I'm unsure which cylinder type is in the v1 mechbox so make sure to figure out if you need a type 0 / type 1 / etc.

If I were doing what you're doing, I'd probably take the whole thing apart and clean all the shattered pieces out (they tend to get into your gears and piston rails and other areas) and regrease with Superlube or some other Teflon (PTFE) grease like the Modify gear grease. If you can get Superlube synthetic grease, get it because it will last you for ages and is superior to almost everything else on the market (and is safe for everything in an AEG).

Be extra careful when installing a sorbo pad in a gun which beforehand didn't require any angle of engagement (AoE) adjustment. Installing sorbo pads usually requires you to remove a tooth from the piston. If you do decide to go with the Modify ultra high speed piston, it already has the correct tooth removed for an AoE adjustment (hence the name "ultra high speed piston"), but if you go with some other piston, make sure to check this. For example, some of the SHS pistons don't have any teeth removed, so you typically have to go at them with a dremel before running your new setup.

For the spring guide, just stick with the stock one you have. Version 3 spring guides have big fat tabs at the back and I haven't seen them fit in any mechbox other than the V3 so far. Also, it won't really make a big difference for yourself unless you somehow managed to destroy your spring guide -- extremely unlikely.

Finally, when you attach your new piston head to your new piston, be sure to use some threadlocker / loctite on the threads of the screw so that you don't have a repeat of this incident Give it over night to cure so that it holds on real tight.

[jordan7831]

Macicka has great advice when concerning aegs, his advice has gotten me out of more than one jam. Be sure to follow what he says to the T.

[cetane]

Ooh. Mech box carnage. Fun fun fun. I've got a v2 torn apart for similar damage. But since I get bored at work I am tinkering with building parts there. Thinking of a titanium cylinder & pom airbrake piston head lol
(can only turn out so many barrel extensions before getting board of doing that lol)