Apologies to Mr. Freeze, no offense intended, but... don't get a clearsoft gun as your tech learning platform. This is a bad idea.
Those guns are much easier to gimp beyond repair than a proper full metal AEG with a decent mechbox, and the price difference is narrow enough that it's not worth cheaping out. You'll strip a threading or crack something much quicker, not to mention cheap clearsoft stuff (as mentioned above) has terrible tolerances and you'll be struggling with the
WRONG LESSONS instead of actually learning the fundamentals of compression, AoE, wiring, gears, shimming, motor height, neo motors vs. non-neo motors, etc. You'll be getting all the heartbreak without any of the wisdom. Just don't do it.
For those in here telling you to start with a cheap TM off the AV used market or something, that's an exception since you'll have excellent on-spec tolerances and can easily use a wide array of standard parts, all the way from cheap to expensive, and you're not as likely to crack or strip something if you're not forcing things (due to bad tolerances).
Seriously, don't waste your time working on "cheap" stuff. Note my choice of words, cheap doesn't always mean inexpensive.
The bang for buck here is important. The other thing you need to think about is what's easily available to find parts for. With non-AR guns and unknown-brand stuff, it's going to be harder.
Your best choice for learning how to be a mechbox hero is to buy the least expensive full metal AEG you can find - a King Arms M4 - and taking it from stock to amazing. With an AEG of this caliber you have very little chance of permanently screwing anything up that you can't repair, even the parts of the bolt release are available for cheap (the parts market in Canada has tons of super-inexpensive KA and SHS parts, these are both KA).
and then following a rough lesson plan like:
1) Shimming and motor height (these go together like bread and butter) until the gun sounds perfect - the first thing to do on a stock gun.
2) Analyzing and adjusting angle of engagement with sorbo and/or washers and shaving piston teeth to reduce chance of piston engagement and shredding problems as you keep upgrading.
3) Testing compression system and improving it with better o-rings / Teflon / floss mod / lubrication / tappet plate mod / nozzle swap / etc.
4) Bushing swaps.
5) Piston swaps.
6) Troubleshooting misfeeds and problems with hopup, buckings, nubs.
7) Upgrading from Tamiya connectors to Deans, soldering bullet connectors to snake through the receiver-handguard gap.
8) Motor upgrade
You want to be learning the above lessons, not the lesson where you sit around JB welding a cracked part or the lesson where you need to sand down the interior of your gearbox shell because no aftermarket bushings work because the bushing holes are out of spec... etc
