Dismantle FA-MAS Gearbox

[Carson]

Having had very little luck finding a guide on how to dismantle the Fa-mas F1 gearbox, I decided to create one myself. It’s also my first one as well.

 

So here is a step my step guide on how to dismantle your Version 1 gearbox, for what ever reason you may have.

 

Obviously, in order to take apart you Fa-mas you are going to need some tools. A small set of basic Philips (the ‘+’ head ones) and flat screwdrivers, a pair of pliers (preferably long nose ones), a Torx screwdriver (T-10 works well) and a set of precision screwdrivers always comes in handy.

 

 

Now that you have all the tools, lets get started. Start by removing the screw on the butt late of the Fa-mas. This will allow access to the back of the gearbox and to take the next piece off.

 

 

Now remove the screws on both sides of the Fa-mas that is holding the main cover of the gearbox in place.

 

 

Having removed the screws, you need to carefully pull up the cover from the front (near where the hop-up is) and then slide in off the back of the gearbox. This will expose the gearbox and the next screws that need to be undone and the connector for the trigger mechanism.

 

 

The small white piece of plastic connects the trigger mechanism in the body to the trigger mechanism in the gearbox, and need to be removed in order to remove the gearbox.

 

 

Taking a pair of pliers grab hold of the edge on the top of the white connector and carefully pull the connector up and out of its little hole.

 

 

Now before you go ahead and undo the last 4 screws holding the gearbox in place, you need to undo the electrical connection between the body and the gearbox, this is a simple mini tamiya connection.

 

 

Now you can undo the 2 screws on either side of the gearbox that are circled in red, whilst at the same time supporting the gearbox so that it doesn’t move while you remove the screws.

 

 

Having removed the 4 screws, you can now remove the gearbox from the Fa-mas, it should just pull straight back out of the body, although one of the plastic arms that holds the gearbox in place may need to be pulled outwards 1 or 2mm with a screwdriver.

 

[Carson]

Notice the hopup chamber is now exposed and can be given a quick spray with silicone lubricant before you put the Fa-mas back together.

 

 

Now that the gearbox is out of the Fa-mas, you need to remove the plate which houses the selector in, this is done by simply removing 2 small screws at either end of the plate.

 

 

Having removed the plate from the bottom of the gearbox, you can now start to dismantle the gearbox. But wait, before you rush ahead and undo all the screws there are one of two things that must be done first.

Firstly, you need to remove 2 spacer like plates from in front of and behind the motor as show in the photo.

 

 

To remove the rear spacer, a small bend on the other side of the gearbox needs to be straightened out to allow the spacer to slide out smoothly. (Mine broke off a while back, but you can see where it would be).

 

 

Having straightened out the bend on the spacer, you can now carefully pull the spacer out with a pair of pliers as shown in the photo below.

Do the same for the spacer at the front of the motor, however, it doesn’t need anything straightening out, so just pull it straight out with a pair of pliers.

 

 

Now we are ready to start undoing the screws on the gearbox. The ones that need to be removed have been circled in red. (Yes there are already some missing, I started taking them out before I remembered to take a photo).

Start by removing the Torx screw that are not in the 4 corners of the gearbox. DO NOT remove the corner ones yet.

 

 

The first thing to do now, is place one hand on the gearbox as shown and apply a little pressure, then carefully remove the last of the screws without removing your hand from the gearbox, (the force from the spring inside make force the gearbox to open and send bits everywhere if you do, I speak from experience).

 

 

Having removed all the screws, its time to open up the gearbox. My technique for doing this is probably not the best, but it works.

Get a small (ish) Philips screwdriver (a large precision screwdriver works well) and put it down the nozzle of the gearbox as shown, be careful not to go too far down.

 

 

With the screwdriver in the nozzle, apply a little pressure so that the tip of the screwdriver is pushing down on the nozzle, this will hold the cylinder inside the gearbox down thus hopefully stopping the spring from sending bits flying.

At the same time slowly prise apart the 2 sections of the gearbox, to stop the gears from moving, it may be a good idea to get a small screwdriver and carefully push it through the holes where the gears sit.

 

 

Now, carefully, lift up the spring guide whilst taking some of the force of the spring and release the pressure in the spring. (Not surprisingly, I couldn’t take a picture of this, as I needed both hands to stop the spring from flying out.

Once done, you can fiddle away at your hearts content and upgrade anything in the gearbox.

 

[Carson]

And finally, all or most of the parts of the now dismantled gearbox.

 

 

 

Comments will be gratefully received. I’d also be interested to see if anyone does it differently.

 

+1’s will also be gratefully received

 

 

Carson

[Bob the Angry Potato]

Amazing guide! This is going on my favorites, definately.

When the M100 spring arrives, this'll come in handy.

[sadigh]

nice guide mate, Im impressed! Just a quick question though, those spacers on the motor - do they reduce the noise that the motor makes?

[fruitleader]

Nice guide, very useful when i buy a FA-MAS very soon.

[systema]

Darn, wish you made this when I still had my FA-MAS. Great tutorial, nevertheless

[Carson]

Thanks for all the positive comments, glad that my first guide has been a success and that you've found it useful. Cheers .

 

nice guide mate, Im impressed! Just a quick question though, those spacers on the motor - do they reduce the noise that the motor makes?

<{POST_SNAPBACK}>

 

To be honest, im not too sure. I think they are there to correctly position the pinion gear on the Bevel gear, and take up a little of the slop that you have when they are not there.

[Boba_Fett]

The motor spacer adjust the motor right to the bevel gear

 

And a hint: Forget about the screwdriver inside the nozzle.....that´s real horror!

 

Get a curved tool and stick it right into the hole inside the V1 gearbox shell to fix the spring and the piston when opening Also do so when closing....

 

http://www.blowback.de/board/thread.php?threadid=21874

 

Here´s my tutorial ... written in german ...but the pictures should help understanding what the curved tool is for

[Bob the Angry Potato]

Carson, since you’re the FA-MAS guru I’m going to ask your advice on this one.

 

You know that little white bit, where the trigger bar is?

 

On my FA-MAS, it’s black- and I don’t know how to remove it. Just pulling and trying it with force it didn’t work, I gave up, put it back together and haven’t looked at it since. I didn’t want to damage it.

 

However, I’m planning some internal upgrades during the winter- and I’m going to ask for a bit of advice.

 

First, how do you remove that part? I’ve done everything except I can’t disconnect the trigger bar from the mechbox.

 

Second, any upgrade advice? Parts to get, where to put them?

 

I’m maxing out at an M100, that’s enough for me. Not sure what velocity that’ll get, but I’m not going to mention forum limits (I’m sure it’s either at limits or only a few feet per second higher).

 

If ANYONE has the PDF version of the FA-MAS upgrade manual from AirsoftPress, please PM me.

 

+1s will be rewarded to anyone with good advice, hints, pictures, or the AP upgrade manual.

[Carson]

Oki doki, The first this is....can you get a photo of your version of the part that connects the gearbox trigger mech to the trigger mech itself. At least this way i can see what its like and try and explain how you remove it.

As for upgrades, I put an M100 into my Famas some years back and it put out about 310fps which is....well, good enough for most people. Much higher and you will hinder the RoF even more.

I've had a couple of people PM me about which gearbox bits will fit in the version 1 shell, and to tell you the truth im not 100% sure, i shall try and find my reply to a PM i sent about this and post it up for some help. But if anyone has had personal experience with different gearbox parts in a version 1 shell, then feel free to either educate me or agree with me, if you wish

[Carson]

Apologise, system was slow and posted twice.

[Carson]

i shall try and find my reply to a PM i sent about this and post it up for some help.

<{POST_SNAPBACK}>

Ok, well unfortunatley I cannot find the message I said I would try and find. So if anyone knows what will and wont fit, please feel free to post it up.

[Onechance]

The motor spacer adjust the motor right to the bevel gear

 

And a hint: Forget about the screwdriver inside the nozzle.....that´s real horror!

 

Get a curved tool and stick it right into the hole inside the V1 gearbox shell to fix the spring and the piston when opening Also do so when closing....

 

http://www.blowback.de/board/thread.php?threadid=21874

 

Here´s my tutorial ... written in german ...but the pictures should help understanding what the curved tool is for

<{POST_SNAPBACK}>

 

Hold what do you do?

Hold the spring back with the curved tool and then lift the shell up?

[Boba_Fett]

JUp, That´s it REmove the patch on the sticker of the gearbox. Now you will look right inside the shell with parts of the spring and piston revealed. Now get a curved tool and catch the piston. Together with the piston also the spring is fixed. Now you can open the gearbox

 

And for some interchangeable parts:

 

V2 spring guide can be modified to fit the V1 but it is about one inch smaller; stick with the V1 one.

 

Piston and pistonhead is fully interchangeable; get a pistonhead with bearing.

 

Also any cylinder might fit, some with minor modifications at the end.

 

90% of all available gear sets will fit. It´s a question of a 1/10 of a millimeter.

 

V2 cylinder head can be installed but I always found the V1 to be the better soluton.

 

Cut off, anti reversal, tappet plate, swich unit...these are all FAMAS-only parts Even the springs for cu-off and anti reversal.

 

Bushings are standard 6mm ones.

[Bob the Angry Potato]

Oki doki, The first this is....can you get a photo of your version of the part that connects the gearbox trigger mech to the trigger mech itself. At least this way i can see what its like and try and explain how you remove it.

As for upgrades, I put an M100 into my Famas some years back and it put out about 310fps which is....well, good enough for most people. Much higher and you will hinder the RoF even more.

I've had a couple of people PM me about which gearbox bits will fit in the version 1 shell, and to tell you the truth im not 100% sure, i shall try and find my reply to a PM i sent about this and post it up for some help. But if anyone has had personal experience with different gearbox parts in a version 1 shell, then feel free to either educate me or agree with me, if you wish 

<{POST_SNAPBACK}>

 

Sure thing. I'll need some time, though, the FA-MAS is put away- however, the only real difference I can tell from yours is that it's black.

 

Cheers, it'll be up ASAP.

[WizardofAirsoft]

The famas precision barrel-is it straightforward to install? If not,any advice or tutorials would be greatly appreciated (I havnt worked out how to do +1s but if someone tells me I'll give them one lol)

[pang]

The famas precision barrel-is it straightforward to install? If not,any advice or tutorials would be greatly appreciated (I havnt worked out how to do +1s but if someone tells me I'll give them one lol)

<{POST_SNAPBACK}>

You'll need to take apart the whole gun to get to the inner barrel, and thats a real pain.

Refer to the complete FAMAS disassembly guide, written by none other than the FAMAS guru Carson for instructions on taking apart the FAMAS.

[WizardofAirsoft]

Thankyou

[Bob the Angry Potato]

Sure thing. I'll need some time, though, the FA-MAS is put away- however, the only real difference I can tell from yours is that it's black.

 

Cheers, it'll be up ASAP.

<{POST_SNAPBACK}>

 

Finally got around to taking pictures. Sorry for the delay.

 

[Carson]

Well, apart from that small black piece it all looks the same as mine. Is the little connector bit (the one thats white on mine and the bit your having problems with) made of plastic?

If yes, (which is what it should be because it would be stupid to make it out of metal when the rest of the gun is made of plastic,) then i guess it may be glued on fairly tight because it is highly unlikely that tokyo marui will have permanently connected the trigger mech together. So what i suggest you do is the following:

First, find something that you can use to push down the trigger mechanism bits either side of the black plastic connector. im not too sure on what would work best having never had to do this.

But anyway, next fint yourself a pair of pliers that will get a good grip of the connector, then carefully full whilst moving the pliers to the front and back of the gun.

(If that last bit didn't make sense then hopefully this will. You have the pliers attached to that bit like i illustrated in the guide, then whilst holding the pliers and the bit firmly tilt the pliers around the connector to the front and back of the gun slightly whilst pulling the connector out.)

 

This should HOPEFULLY wriggle the connector free of the trigger mechanism and break any glue that may be holding the connector in place. Failing that.... well, to be honest i really dont know without having it in front of me.

Good luck, if you have any problems i would be happy to try and help you.

[Carson]

I know I haven't been on here in a while, (what with sorting out Uni and such like), but i have put a copy of my 2 famas guides, (for those who have forgotten: this one and the Famas takedown one) onto my new website which is where i shall be placing all of the new articles as well. This also means that anyone who wishes to view these articles can do so without having to create an arnies account.

 

For the famas guides visit: www.j-carson.co.uk/airsoft.htm

[Pain_is_Red]

Excellent guide, thanks for taking the time to post. I may get one of these in the future, nice to know there will be a guide available now.