Voltage drop in Turret length wiring trade-off

We are trying our first Turret system and struggling with voltage drop in our ~5ft umbilical cord which uses it’s tension to fold back on itself within a circular bin. I think it is flexible 12 gauge wire that is required on 40A breakers. Using 2 Redline 775’s into a 18:32 chain reduction seemed like it would have more than enough rpm and torque from our prototype. We have 4.5" dia. aluminum wheel which also serves as a 3lb flywheel, and have 1.25" Power Cell compression.
Currently, it is taking nearly 4 seconds to spin up to 5k rpm; and with PID control, does have some lag regaining 5k after each shot. It tops out at about 6k rpm. We bypassed the umbilical cord and have about a 2 second spin-up with overall better results.
My question is with the obvious voltage drop in the wire, will we be hurting ourselves reducing the flywheel mass by suffering a greater rpm drop to recover from? Actually, there are many questions when combined with gearing and wire gauge. Any insight would be appreciated.

I’d like to point out that 12 gauge wire is the minimum requirement. Nothing in R53 precludes using, say, 10 gauge wire. Or 8 gauge. Or 6 gauge… though that last might get a bit heavy.

That may help get the electricity through the umbilical better.

Yes, I worded that wrong. We are using the minimum 12 gauge for flexibility. And like you said, we are hesitant to fit 4x heavier 10g wires into our turret tub as we call it. It is a small profile to expect the wires to “roll” in.
At this point we are debating increasing the gauge, reducing the flywheel weight, or the gear ratio.

That does sound like a heavy flywheel!

What you might want to do is to try the heavier gauge wire external to your rigging to see what the improvement is; it would tell you rather quickly and with far less effort whether/how much changing out the wire would help.

At the same current, increasing 2AWG would cut the line loss to about 63% of the present value, 2AWG would cut to about 40%. If you’re currently getting about 6V loss, those would be 2V and 3.6V gains.

There are high-strand count wire types that are much more flexible than the standard wire. The individual wire strands are much smaller than in the standard wire. For each nominal wire size, there will be several combinations of number of strands and strand size (see this chart for an example). The insulation is often a softer and more flexible material such as silicone. I purchased some from Amazon for a personal project. I have noticed in my personal project and work projects that the high-strand count wires/cables often have larger overall conductor diameter than for the standard wire so the next larger lug may be necessary.

Our current attention has been on the wire length resistance and flywheel mass.

I just found out we used 12AWG Copper Clad Aluminum and planning to replace wt Oxygen Free Copper. Not sure if we will try 10, but I see the gain would be significant.

Regarding Flywheel mass, we are now down to 2.1lbs. I’ve looked for what others are using with little results. Probably because same mass at different diameters and rpm have very different inertia. I don’t even know how to quantify for comparison if others shared their configuration. So I’m open to others experience and observations.

So, regardless of AWG, we will suffer some voltage drop over this length and the current. Considering the flywheel mass positioned near the outer diameter of the wheel, do you have any estimates on common flywheel weights?

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