How to Shim!

[cbcsteve]

I always had troubles with shimming as I never had much patience with figuring the perfect shimming.

Thats until I found this great Shim Template to start from but of course this is not number 1 model just something to start from and them move up from

http://www.arniesairsoft.co.uk/?filn.../shimguide.htm

Just make sure the Shim set you get has all those sizes

[dpvu]

The key is to start from. You can't rely on that guide as there's so many variables that come into play when shimming. In the end it's all trial and error anyways. It's not terribly hard but I over-shimmed my first time.

[Dusti69]

i have somewhere between 12 and 14 shims total in my krakens gearbox but only cuz i only used all the really thin ones.
it sounded really rough before i started and it sounded a lot better when i was finally satisfied but still a little rough so i dunno if i did a good enough job

[m102404]

Steve,

Be cautious relying on a set formula...it won't work on every gear/mechbox combo...

You're aiming for 2 main objectives:
1. As much tooth/tooth contact, without the gears crashing into each other
2. Minimal side to side movement while keeping the gear train moving as freely as possible

I really like this guide...great pics and details on what needs to clear what.

http://pageproducer.arczip.com/daedalus03/shim.html

[Amos]

Another way to test for proper shimming:

Once you've got all the shims and everything in, remove the compression part of the gearbox (cylinder, tappet plate, piston, spring, guide) and close the gearbox back up.

If you can spin the gears by hand and you can make 'em do a couple rotations your shimming is pretty good.

(With one of my guns that had 7mm bearing bushings, I was able to make Systema Torque helical gears do 6 rotations!!)

[Dusti69]

is the kind of noise the gears make when fired an indication of good or bad shimming? all my gears line up pretty well and they move well in the gearbox without side to side movement yet it still makes the rough RRRRROW! noise only its a little higher pitched after shimming

also.. is grease and oil in the gears turning grey normal?

[cbcsteve]

Yeah same for me even with the guide I still cannot perfect it, still that high pitch Rrrowwr but it still shoots

[Dusti69]

see i also wondered if maybe it was the krakens unique sound cuz i have guns with custom built echo1 and a classic army, a d-boys, and two jg's and they all sound differently. even the two jg's sound differently
but my krakens gears sound really dry and rough like sorta in a bad way even though it seems as though the gears are shimmed good enough

[cbcsteve]

Yeah I do the non-compression closed hatch gear spinning technique and they spin nicely and then once shooting begins it makes a Rwwrroorr

Most of the time I hear the Rwwrrorr is:
- Bad shimming and grease job
- Gear teeth are dying
- Worst of all gearbox is deformed

[Dusti69]

for me it cant be not enough grease. i degreased and re-greased with white lithium and with a lot of it and bearing grease/oil around the metal bushings. hope my gear teeth arent soon to be fucked. all the grease around the gear the motor hits is dark grey. i have a feeling thats where the problem lies

[cbcsteve]

A friend told me that the dark grey colour is from the gears grinding too tight with each other so maybe loosen up on some of the shims or it could be that the gears are grinding against the walls which probably means that the shims are not perfectly balanced with each other

[Dusti69]

its only on that one gear. it lines up good with the next. no side to side movement in the box yet still moves fine. i heard someone here say youre not sposed to have a shim under that gear and only on the flat top of it. i have one thin shim under that gear

[Styrak]

Grease going grey is normal.

[Dusti69]

Originally Posted by Styrak

Grease going grey is normal.

thank you sir! that shits been freakin me out for some time now. thats one less thing i have to worry about in my gearboxes

[RedblAze]

Originally Posted by m102404

http://pageproducer.arczip.com/daedalus03/shim.html

anyone else getting "page cannot be displayed" or is it just me? =/