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NewsonNerf

MTB Wolverine Stryfe MOSFET *UPDATED*

I really wanted to give the MTB 180 line a shot and see what they were like, so after browsing on BlasterTech, I noticed that the wolverines were back in stock. ( At this point I wasn't aware that they were available at blastersmiths). I bought two of them with a Cherry DC2 for the build.

I started with a blue Stryfe acquired from eBay, I stripped the internals and proceeded to cut the 180 window. Although the cuts went well, I made the mistake of removing too much material and breaking into the mag well. This was due to me following the motor bump lines in the shell.

For the internals side of things I used a IRLB3034 MOSFET. After receiving some feedback I decided to act upon their suggestions and go the MOSFET route. I already had these parts in stock before hand but neglected to use them here, simply because I though they would be used better elsewhere. All of the high current wiring is 16awg in the top of the blaster, and the low current 'signal' wire is 18awg. I used the wiring schematic from Tom's MOSFET guide. I have built a functional MOSFET loom perviosly with MTB Honeybadgers. This used the IRFZ44N MOSFET. I have kept the Cherry DC2 as the rev switch in this build as I greatly prefer the DC2 feel over the stock switch. I also changed the wiring method at the motors. I used the method that reduced strain on the terminals and is much more aesthetically pleasing. The motors are MTB Wolverines. This blaster runs from a Turnigy Graphene 2S 65-130c 1000mah. Externals are the blastersmiths 3D printed motor cover and extended battery tray, beautiful duarable parts that match perfectly with elite (dark blue). Also in this build is the brand new 3D printed Hawki007 BSP. This is the non canted version that was released to the public. It does not require brass. I used the 3D printer at my school to print this from thingiverse. It is an amazing part which fulfills the role of an upgraded cage very nicely. Keeps your blaster light and simple but with a bit less vibration. Well worth looking at. The performance from this cage is what is expected of it. Propels darts at the correct velocity with no fishtails. The flighwheels have a very high crush, which fully takes advantage of the tourque outputted by the wolverines, as mentioned in FDS's recent motor video.

Also in the pictures l, you can see a DIY thumb screw. This was constructed out of 4 layers of sheet styrene. A small hole was drilled through the first circle to allow the threads to pass through. Then a larger hole was made in the one piece to accommodate the head, this was repeated for the third. Then the final circle was just cap peice.

Overall very happy with this suletup currently, the motors are quite loud but that may be due to external vibrations. The 3D printed covers are incredible, I would expect nothing less from BSUK!. A small note about the motor cover, you can see two strips of plastic on the edges. This was due to me making the aperture slightly too wide, I made this mistake on my XP180 Stryfe. I used to small strips of blue plastic from a donor Stryfe to mask the small slits. These look very white and rough in the pictures but look very at home on the shell. The strips also help to 'blend' the cover into the shell, the make it look more fluid as there is a second peice.

I'm very greatful for the feedback on this build to further improve the quality of my work. I am so pleased to have acted on this because it has really pushed this blaster up the ranks. Within one day of completing the build, it has already been stripped and re wired for the better! Thanks again!

Let me know if any links fail, or drastic spelling errors!







































OldNoob

That looks great. The only thing I would change is first match the flywheels, that helps reduce noise, second change the wiring of your motor block. You shouldn't loop the feed through the first motors' terminals. Look at how Franksie and BG did theirs, with the feed between the two link wires.
I would also upgrade that loom to mosfet, that's my personal preference, the components are cheap.
Clear signs of some developing skills in this build, well done. Interested to see what you make next!
Franksie

Here's my cage that ON is talking about:




Agree about the MOSFET too - that's a lot of current being pulled through the hand grip that I'd rather have somewhere else
Boff

Even if you don't upgrade to a MOSFET, please at least swap that poor Cherry DC2 micro-switch to a 21A rated full sized one before it melts. You've got less than 1000 shots before that happens in our testing. Of course, MOSFET is love, MOSFET is life but I can understand if you've already done the dremel work for the micro then you might not want to. Of course, you could just fit the FET and reuse the DC2 for the gate signal instead of the stock microswitch. Smile
SSGT

Boff wrote:
Even if you don't upgrade to a MOSFET, please at least swap that poor Cherry DC2 micro-switch to a 21A rated full sized one before it melts.


This.

It's a really nice build nice build the longevity of that DC2 does worry me. DC2s are rated to switch 10A resistive loads or 1.5A motor loads at 250VAC. If they de-rate anything like full-size switches their rated current for a motor load at 8VDC will be in the region of 1.25-2x the rated current for a motor load at 250VAC so somewhere in the region of 2.25-3A continuous. If the inrush current rating also scales similarly (since it has a EN61058-1 rating it should do) that'll be 6x continuous current so something in the region of 13.5-18A at 8VDC (for comparison a full-size 10A switch is rated to 18A inrush at 8VDC and a full-size 21A is rated to 42A inrush at 8VDC). A pair of Wolverines on 2S will draw up to 95A at startup which is technically well beyond even the rating of a full size 21A although, given that DC2s seem to hold up relatively well to the circa 45A inrush of a pair of 180s, it may be able to cope it just won't last as long as specced. A diode in the loom should help with reducing switch damage though, at least when releasing the rev trigger under load.

The fact that a high current is passing through the grip isn't, in of itself, necessarily a bad thing. Just because 90A is passing through the grip at stall doesn't mean 90A will pass through you if something goes wrong - V=I*R still applies (especially if you use a diode to give that current a path to free wheel so it can't induce a voltage spike - more voltage across the same resistance equals more current) and the human body has a very high resistivity compared to the copper wire in the wiring loom. Minor burns are a possibility if the switch melts or bare wires come in contact with each other although you do have the protection of the pistol grip which is unlikely to melt in the brief period it'll take for the switch to burn out (unless it fails closed but at that point pack failure would be the pressing concern and a FET failing closed would be no less dangerous). That said, given the above, a FET would be a reasonable idea in this instance anyway (as Boff said, you could re-use the DC2 to switch the FET). EDIT: Just seen the update, I see that's the route you've taken. Quite honestly I can't help but think you'd have been better off with a pair of Hellcats or a pair of (albeit more expensive) 3240s. Wolverines on 2S draw more than twice the current of Hellcats and spin more than 30% faster even though Hellcats already spin fast enough for all but insane multi-stage setups. If they produced significantly more torque it'd be an easier sell but as it stands they only produce 6% more at stall than a Hellcat.

On a more positive note I personally don't think there's anything wrong with the "toruk method" of wiring motors, as long as the wire is a continuous length soldered against the first motor's terminal and not two lengths soldered to a single terminal individually (in that case current to the second motor may be passing through the first motor's terminal to get to the second length of wire which at best will add resistance and at worst could result in it overheating). Yes, the extra length will result in a slightly greater resistance between the pack and the second motor but you're talking less than 2 milliohms difference (less than 1.3mΩ in the case of 16AWG) total if you wire both sets of terminals the same way - if you wire them in the opposite direction, i.e. left side top to bottom and right side bottom to top, that'll cancel out but given that motor speed between different motors of the same wind will vary (Ryan from MTB has been quoted as much as 10% by manufacturers) the additional resistance is negligible and really doesn't matter - if both motors stay above the critical speed for the setup, minor differences in speed won't matter too much anyway. The fact that it reduces the number of physical wire joins (potentially reducing overall resistance and removing potential points of failure) is, if anything, a plus.
OldNoob

Wow Barney, that was ninja fast! Not looking forward to facing this at a game.
Minky

Great work! I hadn't realised the BSUK blue was such a close match..  Think that counts as a Sleeper until you press the rev trigger lol

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