Friday, March 20, 2015

The Next 2s Solution?

When looking for some e-sky and blade motor listings, I came across these:

Their specs are quite superior in terms of 2s lipos, drawing 0.75A continuos each while blades would draw ~0.6. The RPM on these would be hitting the 40k mark while blades would hit ~28k. For 3s, I still think blades would be better but these seem to be better on 2s. In terms of price, these are about $3 a piece which seems to be a bit cheaper!

Since these are 180's, their inertia and torque should be substantially higher than that of 130's. These are in fact, carbon brush so there is no need for getting all worried about stuff like: "Am I going to burn out these motors?". For those of you who aren't familier with what carbon brushes are, here's a photo:

Photo credit goes to SSGT on britnerf.

So basically, the things on the left are parts of a standard metal brush motor. the brushes which are the things at the top are very thin. The problem with that is that you will be sparking these brushes all the time whenever you put power into the motor. That brush will get worn down as heck! Now look at the things on the right. Those are the parts of a carbon brush motor. Look at its brush set at the top. It has two chunks of weird things right? Well those weird things are what makes carbon brushes carbon brushes. They are chunks of carbon that help with brush wear.


  1. I've also come across those motors while trawling for 180 listings. There is an inconsistency in the description - it says 32 000 rpm at 6v in one place, and then says a max of 30 000 rpm at a max of 12V right below that. I couldn't find a model number for these motors in this listing. It is worth noting that, of the 180-SH motors that Mabuchi currently has in their web catalogue, some are precious metal, not carbon, brush.

    Mabuchi FK 3534 motors are another possible replacement for 3240s. These are the motors that were tried out on the BritNerf forums ( ); this thread contains links to ebay listings for 3534s.

    1. I think he means that's the max speed with a load.

      I also saw the 3534 motors a long long time ago. They seemed to have half decent specs but I don't think the torque would have been good.

  2. I suspect these may be a -3831 wind (slightly hotter than the -3534) based on the 32K@6V spec.

    The images show something that at least looks genuine Mabuchi and has the edge of an old school Mabuchi data label visible.

    These two winds are hotter than -3240 and thus interesting for flywheel applications due to the scarcity of the genuine -3240. I see two problems presenting themselves. One, a lot of these motors might be Chinese generics and poor quality. Two, I don't know about the suitability of the hotter motors, the -3240 is already quite ideal and these lower turn motors will be less efficient and get hotter and be harder on the brush gear. They might also not have the excellent torque rise characteristic that makes the -3240 and its RC aftermarket replacements so great for response and rapid fire without cooking darts or being extremely loud and OTT.