Technical information

Practical A.E.G Upgrade 2006
Page 54 Copyright 2005,06 The AirsoftPRESS (Hong Kong). All rights reserved.
What is an easy way to (more accurately) shim?
The goal of shimming is to keep the spacing of gears correct. Marui has a set of
“official shimming standards” for the V3 mechbox:
These “standards” were devised based on the assumption that you use solely TM
stock gears with stock plastic bushings inside a V3 mechbox. Therefore, they
serve as good references but NOT absolute standards.
Most shim washers in the market have sizes of 0.2mm, 0.3mm and 0.5mm.
There are 0.15mm and 0.1mm available from some Japanese manufacturers too.
Use the SMALLEST possible shim washers to make the finest possible
adjustment.
Start with the least number of shims. What you may want to do is to test fit the
gears one by one incrementally. The test fitting process requires that you insert
the gear in question and put the mechbox back together, then check for ‘slop’
from BOTH sides. Keep adding shim washers (or changing to a larger one) as
long as ‘slop’ exists (but don’t add too many or the gear will have a hard time
spinning).
Order of gear installation: first is the spur gear. Next is the sector gear. Finally
are the anti-reversal latch and the bevel gear. Don't forget to apply grease when
installing the gears!