9 replies to this topic

[Xhosant]

So to get started, the Magnus effect in short: when a cylinder or ball moves forward and spins in a 'reverse roll' style, it produces lift.

In more detail: https://en.m.wikiped...i/Magnus_effect

In action:


So the question is, could we tune the motors of Rival flywheels to spin with a speed just different enough to give backspin, thus lift, thus range? And is it worth it?

[shandsgator8]

It would work in theory. I think some Rivals blasters (the Zeus?)  already have this "hop up" ability, but I could be wrong.

[Xhosant]

Oh, yea, a little research reveals it has a little flap in the barrel to brush against during launch and give backflip.

Still, can't help but wonder, would the motors imparting the spin not be better than wasting velocity impacting the flap? Needs some testing, shame I lack a zeus.

[Daniel Beaver]

Oh, yea, a little research reveals it has a little flap in the barrel to brush against during launch and give backflip.

Still, can't help but wonder, would the motors imparting the spin not be better than wasting velocity impacting the flap? Needs some testing, shame I lack a zeus.

 

The energy budget of these two systems would be pretty similar. 

[miatahead]

The hop up is probably the cheapest way to get consistent spin and not having to worry about balancing the speed between the motors.

 

The Hera has horizontal flywheels and a hop up at the top of the barrel.  It consistently throws a slightly rising shot, whereas my Artemis with no hop up throws balls with spin in all directions, so it is less accurate.  Shots go down, left, right and up with the Artemis.  I prefer the rising shot of the Hera as it gives it better range and reduces the left/right curving shots.  IMHO, the hop up is the most efficient, easiest and cheapest way to make shots consistent.

 

To do this with flywheels only, you'd probably need to decide between passive or active speed adjustment and then depending, how that would be accomplished.  My first thought would be a passive approach to add resistance to one motor.  An active approach might be to add something like a potentiometer to each motor, that way you can adjust the speed of each separately?  I guess if you have programming skills, you could use a board, display and some buttons.

 

I'm sure it can be done, but seems way more complex and costly.  But I wonder what I'm gonna do when that hop up wears out.

[Xhosant]

Sounds like a reason to figure how to make our own! Can you get any measurements? Think spreading some silicone caulk thin and cutting one out could work?

(I have my eye on a blaze storm rival zeus, a zeus knockoff with decent workings, bigger frame for easier modding, half the price and no hopup, so this is extra interesting for me)

[miatahead]

OutofDarts probably has the best data on hop up wear, as he's probably shot a sh*t load of balls thru Zeus and he's the only person I've heard say they wear out.  He probably has an idea of how to replace them, but I can't see there be any money in that since its just a piece of foam probably the size of half a postage stamp.  I can't take mine out, but it feels something like a soft rubber flap.  Much firmer than silicone, but softer than a rubber washer.

 

I'd bet a suitable replacement could be found in either a craft store or the hardware store.

[Draconis]

...whereas my Artemis with no hop up throws balls with spin in all directions, so it is less accurate.  Shots go down, left, right and up with the Artemis...

 

 

  Aaaaactually, the Artemis (along with all of the other Rival blasters) does have a hop-up tab present in all four barrels.  It appears to be made of a dense orange rubber, and may be too small.  The one on the Apollo is hard plastic, molded into the barrel.  One of my Zeuses happens to be missing the flap, and it definitely makes a difference in the performance, both in accuracy and range.  I'm going to try EVA craft foam for that one.
 My other Zeus is running a 5S battery, though, and has too much hop up for the ball speed.  I can shoot people around corners and trees, if I rotate the blaster 90 degrees around the axis.  If I happen to get one of the super-light EVA Cornucopia brand balls in a clip, that one will exit about twenty feet and curve straight up in the air.

[Xhosant]

I'm going to try EVA craft foam for that one.

Pretty please, let us know when you try it!

My other Zeus is running a 5S battery, though, and has too much hop up for the ball speed.  I can shoot people around corners and trees, if I rotate the blaster 90 degrees around the axis.  If I happen to get one of the super-light EVA Cornucopia brand balls in a clip, that one will exit about twenty feet and curve straight up in the air.

That is bloody awesome, once used to it. Now I want to build a gun for the job!

[Zorns Lemma]

If the idea of doing it with desync'd motors is to avoid the power loss of a hopup, for the projectile to receive spin, you will need slipping past one of the other motors, which means you have to tune both your motors speeds and tune the friction difference between your two flywheels and not really avoid any power loss compared to just driving both motors at the same speed and imparting your spin later.

You should definitely focus experimentation with homemade hopup modifications and report the results. Alternatively you can probably find some 3rd-party modification that wasn't tested at all but is marketed to do m a g i c and waste money on it because applying critical thinking and experimentation is too much cognitive load.

Edited by Zorns Lemma, 10 October 2017 - 11:43 PM.