Nerf Vulcan Repair and Modification
I purchased a Nerf Vulcan some time ago and was disappointed in the rate of fire. From the factory it chugged out a bit more than one round per second, or about 20 seconds to run through a 25 round clip. The battery pack is 6 D cell batteries for a total of 9 volts. I figured the motor should be able to handle more voltage, so I grabbed a couple VEX 9.6V batteries and wired them up. Everything went great until I reached 4 batteries, 38 Volts. The rate of fire was impressive as this video shows. It emptied the clip in about 3 seconds, twice. You can see how well the motor handled it below. The brushes came unglued, snagged the windings on the rotor, and made a general mess.
The motor itself is a standard size and shape toy motor with no markings. Just over an inch in diameter, and 1 1/4 inch long. Unfortunately in this state I had no way of determining any of its characteristics. I tried guessing the RPM by assembling part of the old motor in place and spinning the rotor with a pair of vice grips. That got old and the gear kept slipping, so I resorted in trial and error.
The first batch of motors came from The Electronic Goldmine, but unfortunately while they fit fine, they did not have the power or speed I needed. The best motor in that batch fired the gun at near the stock rate with 2x the stock voltage.
Second try was a success. I ordered a handful of motors from American Science and Surplus. The fastest of the motors runs at 13.5k RPM (at 12V) and will fire the gun at 4 rounds/sec at 27V. A 60 second test firing indicates the motor and the gun can handle this rate. The motor didn’t heat up or smell funny after the test.
If you are looking for the motor, it is a Molon hobby motor rated at 6-12 VDC, at 280ma for 13.5k RPM. AS&S has it here: Hobby Motors
The only problem so far is that the motor is about 1/8 inch too long to fit comfortably in the gun. I’ll need to use some longer screws to secure the orange top to the plastic standoffs, and Dremel out a little of the plastic to make it fit. I’ll post more pictures and video when I get it put back together and shooting.
See also:
Hobby Motors at American Science and Surplus
Nerf Vulcan set on Flickr
August 2nd, 2009 at 3:49 pm
Helpful info, but the site no longer carries the motor you talk about, could you possibly give us a model number or something?
August 8th, 2009 at 1:52 pm
The motor is a Molon CMO-1237 as described on this page.
http://www.eaelec.com/ea_hobby/motors.htm
Google currently shows two sources for it on their shopping search:
http://www.google.com/products?q=Molon+1237
November 27th, 2009 at 8:30 am
is it possible to add a bigger motor for even more rpm?
November 27th, 2009 at 9:16 am
someone should add a nitro motor. it may add more rpm and you have to worry about the motor burning out.
December 16th, 2009 at 3:27 pm
can u give specifc instrucions on the mootr swcih plz
December 16th, 2009 at 11:06 pm
I’m not sure what you mean by specific.
It’s really easy, just open the case, remove the old motor, put the new one in its place, solder the wires to the new one.
January 16th, 2010 at 11:10 pm
They still offer the motor- but it comes as a combo with another motor for $3.95.
http://www.sciplus.com/recommend.cfm/recommendid/11675
Standard shipping for up to $15 is $5.95 (all US dollars)
How much does it cost to get 27 volts inside the gun?
Also, has this thing lasted? The motor still works?
My son is 11. He’s not interested in ANYTHING in terms of building or science or engineering- but he will take apart a nerf gun to improve it. So I’m willing to invest a bit.
But my hunch is that you’re using LiPo cells, and I can just imagine the fire we’ll end up with while charging. And a “safe” charger is pricey, isn’t it?
January 18th, 2010 at 5:53 am
Hi Anton, I’m in need of a replacement motor myself after burning out the stock one. While I’m fine with a Molon CMO-1237/Mabuchi RS-385SH, I’d like to explore other options.
I read your comments in the link to the Youtube video you uploaded, where you said you’re looking into finding a brushless motor alternative for the mod. Could you briefly explain what a brushless motor is, what are its benefits to brushed motors (which I presume the Nerf stock, Molon 1237 and Mabuchi RS-385 are), and what are available brushless motors that are compatible with the Vulcan?
I’m looking to widen my options largely due to living in the Philippines, where hobby stores are few and far between, where toy motors are likely to not be available, and where shipping from anywhere will be too expensive.
Thank you very much!
January 24th, 2010 at 12:43 pm
Brushless motors are used in RC planes and cars and can achieve some amazing speeds. They are not cheap and require electronics to drive them.
January 24th, 2010 at 12:44 pm
I used three 9.6V NiCD Batteries. They are usually used in RC cars and/or transmitters. They are also cheap and easy to charge.
March 16th, 2010 at 3:53 pm
wait so you just take out the old one and just pop in a new one??