Sitting Duck
Supporters
- May 11, 2014
- 4,894
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Sorry Duck, but I'm not swapping a crappy DE box with an E&C oneand I'm not willing to spend time reshimming both boxes.
Also, softairgames is being a bitch and the website doesn't allow me to pay via PP -.-
Remind me again how times your guns have been in bits ???
For the record - haven't got a clue about the gearbox make/brand itself...
The 904 box is a QC reinforced type (so 13:1's will need a minor mod to top half of box for spur clearance)
with the M4 lug on top for charging handle, but with no ARL release slot & some other things
so rules out being quite a few of the branded QC V2's out there
It looked like a possible Classic Army QC - but they are not reinforced at rear like the 904 box
so fuck knows who makes the box
The closest so far appears to be a King Arms 8mm QC v2 gearbox (reinforced)
but details on this box are sketchy & vary - with places like Evike claiming it is KA
(but often is just an China OEM - plus Evike list Cyma/JG as basically the same but are different)
The wiring used in the 904 looks to be 17awg
cutting the spare deans to small tamiya adapter wire...
wire diameter is about 1.13mm thick
compared to 1.35mm for the Alpha Eco 16awg
so Alpha is about 20% thicker to carry more juice
But they have ran 3 wires into the box
1 goes to pos motor it seems
& another pos & neg goes to pcb, then one neg lead to motor
so passing the motor entry you have 2 x 17awg wires
when in theory it might only need say a 20awg positive & then a slightly thicker 16awg Alpha negative
Basically they have ran say basic mosfet trigger signal wire in 17awg when 22awg is plenty
(now the pcb is doing a bit more - but even so the positive supply to pcb will not need any thicker than 20awg imho
BUT the ETU pcb is likely doing a bit of AB so will need a bit more than just thin 20~22awg signal wire)
yet think I could replace the motor wires with 16awg Alpha & be OK at motor entry (just if routed very carefully)
Obviously - this desoldering wires & replacing them is very risky & unsure if I will attempt it (probably not)
but the stock wire could be a slight choke point if pushing it a bit beyond mild snappy build
(But know a mental DSG would be out of the question - maybe a German 250fps DSG might be about limit)
The German DSG would just be a drop in - but really don't want to push the amp draw on the bespoke ETU
So the likely possible option would be a mild mod to top half of box, fit 13:1
& a 25k motor max I reckon is about the most I would likely look to do with it
achieving maybe 17 rps on 7.4v & say 25 ish on 11.1v on a 12amp draw
I know I can squeeze more out on say a reg snappy build, with better wire wire, 30k motor etc...
but sticking on 17awg stock wire, 25k motor tops (maybe 22tpa/22k) there will be some zest untapped
plus I reckon these ETU mosfets nick a little bit of power too over basic trigger/mosfet stuff imho
General idea though is to squeeze out more zest without going ultra nutz on both 904's & the 517
Soz to crash your thread, just my own thoughts & future plans of projects to mess around with
(gotta have something to do with all these lockdowns I guess)
best of luck with your project too btw