Why 3.5mm bullets on focbox?

I’ve come across some focboxes and they seem to have slightly smaller bullets compared to the more usual 4mm. (and obviously 5.5mm) Have we worked out any reason for this? Perhaps if everyone has to immediately solder their new box it’ll void any vague warranty? Apologies to all and everyone if this has been done to death as I seem to have missed it. Are people just cramming in their oversized bullets? Resoldering the new focbox or sourcing 3.5mm bullets for their motors?

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They are probably cheaper, thats how that company makes profit. They cheap out where they can.

Most motors have 3.5mm bullets as their connector. Why should enertion use a different size that would require you to solder either 3.5 to the focbox again or something larger to the motor?

Most motors use a 4mm bullet don’t they?

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I can compare maytech, 4mm racerstar 4mm Hummie 5.5 Jacobs hubs 4mm brother hobby 4mm Alien power systems 5.5 I’ve never seen a motor with a 3.5mm bullet.

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This was discussed a lot in the other thread;

They are using 3.5 bullets because that is all the bigger they need to be, according to the EE’s who designed them ( @johnnymeduse ). It’s what they use for the R2 and 3.5mm can handle enough current. They are probably 20 cents cheaper than bigger connectors which when at mass quantities adds up.

Fair enough, the soldering iron is heating up. But I’m not going mad am I? No one uses 3.5 on the motors except raptor hubs?

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Right! But like told previosly they are probably 20cent cheaper.

Actually the Focbox is using 4mm bullets. My Jacob Hubs fit directly to the Focbox as does my SK3. Also I soldered these https://hobbyking.com/en_us/polymax-4mm-gold-connectors-10pairs-set.html?___store=en_us to my bangood motor and use them with the focbox as well.

Must be the new ones. Now they have 3.5mm I’ll do a comparison.

Here you go, 5.5mm 4mm and the 3.5 on the focbox. If you look at the 1st photo you can see how much shorter the 3.5mm bullet is compared to the 4mm male female set.

I can confirm that newer (raptor 2) focboxes use 3.5mm bullets. I both measured it with calipers and picked up 3.5mm bullets from Amazon. They fit right in (and into headphone jacks too!)


Enertion support said in other topic that changing bullets will void the warranty (as any other physical modification). So if you don’t want to risk it or change bullets on the motor side, I suppose only choice is to make an adapter cable.

But those phase wires look so tiny compared to all others in my build LOL. I’m scared they will break just by looking at them :slight_smile: (I understand the AWG class is enought for the phase wire currents but still…).

Just keep the 3.5mm ones and solder them back on if you ever need to make use of the warranty. They scam you so why dont scam back?