Airsoft Canada

Airsoft Canada (https://airsoftcanada.com/forums.php)
-   Upgrades & Modifications (https://airsoftcanada.com/forumdisplay.php?f=24)
-   -   MOSFET suggestions (https://airsoftcanada.com/showthread.php?t=103869)

doc_pathfinders May 17th, 2010 06:21

DonP, thanks for the info, i was fully aware that i wouldn't have anything fancy RE: Firing modes on the '249 but IMHO a burst-firing SAW isn't something anyone should aspire to :P

also, i've been doing some reading on motor tuning, thanks for that bit of advice..

ThunderCactus May 17th, 2010 19:30

Be warned, I put one on my G&P, V2 mechbox, very stable platform, running an 11.1v 20C LiPo, and it's overheating on most motors after 200 rounds, 40 rounds on a systema magnum.
I highly recommend buying a G&P M120 or M140 and getting it tuned :)
I haven't had any issues since I tuned my G&P M120 motor

Windows May 17th, 2010 19:54

If your looking for a technical answer then any MOSFET with a Vmax over 20 an Imax over 30 should do for most AEGs Just make shure you heat sink it and don't forget that pretty much all MOSFETs take about 1.2V To turn on, so if you may need to upgrade your battery if your already pushing it.

doc_pathfinders May 18th, 2010 02:45

Quote:

Originally Posted by Windows (Post 1236801)
If your looking for a technical answer then any MOSFET with a Vmax over 20 an Imax over 30 should do for most AEGs Just make shure you heat sink it and don't forget that pretty much all MOSFETs take about 1.2V To turn on, so if you may need to upgrade your battery if your already pushing it.

you're not taking into account the peak current on startup, this may be many times the 'rated' current you believe the motor should draw when spooled up.. and as it's airsoft and we stop/start our motors (sometimes many times a minute) this becomes a big factor :)

i could pick up a DIY guide for making a MOSFET (and i have) but i'm looking for something that someone else's blood and sweat has gone into, rather then mine.. because i know that the first few versions will never quite work the way i want, or at all knowing how i punish some things..

also: ThunderCactus.. are you saying your MOSFET was overheating or the motor? and what were the symptoms?

ThunderCactus May 19th, 2010 23:36

The MOSFET itself wasn't overheating the motor per say.
The motor was not only drawing higher amperage than usual, but it also has a notorious overheating issue caused by lack of insulation. But the active braking makes it worse.
Due to the ridiculous amount of current being drawn by the motor in it's active braking and normal operating cycles, the MOSFET overheated

doc_pathfinders May 20th, 2010 02:37

Ahhhh, it makes sense now :) thanks for that bit of info..

how did you tune your motor? true the commutator or using the 'water treatment'? (or did you hand it over to an RC shop and just let them do everything?

ThunderCactus May 21st, 2010 08:34

I have an RC guy with all the right tools, he's really good

doc_pathfinders May 21st, 2010 08:48

bah! i'll have to check in with my local RC shop then to see if anyone will deal with AEG motors...


All times are GMT -4. The time now is 19:44.

Powered by vBulletin® Version 3.8.11
Copyright ©2000 - 2025, vBulletin Solutions Inc.