today's work

[He Who Shall Not Be Named]

https://youtu.be/AHERmXL3qyY

[He Who Shall Not Be Named]

David,
Nice vid whats involved running a rc submarine, both pre mission as post mission
As for my type XXI, cg is under the middle of the tower, angle keeper at it's lowest setting, speed limited to 50%, when run on max power she will take the plunge.
I guess it has to do wirh the hull shape, the V80 loves to run fast ( different hull shape)
That dolphin movement of the boat can be due to the levelkeeper being too sensitive, had the same issue with the V80, turned down the levelkeeper each time untill i had a straight run, i must admit the V80 has a levelkeeper from Norbert.


Manfred.

Good food for thought, Manfred. Much appreciated. Your words carry considerable weight in these quarters. I've already moved the c.g. and c.b forward considerably. Will run it in the local JCC pool tomorrow. I'll report the outcome tomorrow evening. Will try to take similar video as well.

David

[MFR1964]

David,
Nice vid what's involved running a rc submarine, both pre mission as post mission
As for my type XXIII, cg is under the middle of the tower, angle keeper at it's lowest setting, speed limited to 50%, when run on max power she will take the plunge.
I guess it has to do with the hull shape, the V80 loves to run fast ( different hull shape)
That dolphin movement of the boat can be due to the levelkeeper being too sensitive, had the same issue with the V80, turned down the levelkeeper each time untill i had a straight run, i must admit the V80 has a levelkeeper from Norbert.


Manfred.

[He Who Shall Not Be Named]

From a physicist perspective: Does your pitch control have an adjustable controller, i.e. the proportional part? Oscillations can be the result of the proportional part of a controller being set to high. If possible, make the controller less sensitive by reducing the proportional part.

Thanks. If the current 'fix' does not work I'll vary the angle-keepers sensitivity, as you suggest. That should get out of any stern plane device induced ocillations by getting away of the boats natural frequency about that axis. Good stuff, sir.

[DrSchmidt]

From a physicist perspective: Does your pitch control have an adjustable controller, i.e. the proportional part? Oscillations can be the result of the proportional part of a controller being set to high. If possible, make the controller less sensitive by reducing the proportional part.

[He Who Shall Not Be Named]

Looks like the gremlins are back. Didn't you have the same pitch problem in the past?

This is either the fourth or third Bronco 1/35 Type-23 I've assembled and driven. And all of them misbehaved the same: wildly unstable in pitch once submerged. All had a well working angle-keeper, and at least two of them featured a depth-keeper as well. All had the longitudinal c.g. placed at the center of the hull.

Two days ago, I radically changed things by moving weight and WTC forward to place the c.g. about four inches forward of its previous position. This to place the c.g. well ahead of the likely center of pressure, making the boat dynamically stable about the yaw and pitch axis. This change (I hope) will permit the vehicle to 'weathercock' to the flow; getting away from this awful pitch oscillations that likely results from the c.g. and c.p. being too close together. I'm guessing that the c.p., shifting back and forth with each change of angle of attack transits ahead, then behind the c.g. with each pitch swing is the problem. I'm thinking that my type-23's are experiencing a form of the dreaded 'inertia coupling' phenomena some aircraft get into.

[redboat219]

https://youtu.be/ZN-n1sF-r34

Looks like the gremlins are back. Didn't you have the same pitch problem in the past?

[He Who Shall Not Be Named]

Not to distract, but are you bringing Danny Webster to Subfest?

Man! That was the plan, but I got bogged down with some obligations, so I'll just bring boats for camera tows and the like, and one or two smaller ones for newbies to try their hands at this stupid hobby of ours.

Yeah, the Daniel Dumpster-Fire will have to wait till next year.

[Fishb0y]

Not to distract, but are you bringing Danny Webster to Subfest?

[He Who Shall Not Be Named]

went blank at 2:20

Nuts!........

[Ken_NJ]

went blank at 2:20

[He Who Shall Not Be Named]

https://youtu.be/ZN-n1sF-r34

[Subculture]

No gel coat?

You can purchase ready mixed epoxy gelcoat from many resin suppliers. Some also use Vinylester resin gelcoat, which you can use with both epoxy and polyester resin systems.

[He Who Shall Not Be Named]

Sexy sub! Handy size!

The ALFA? Yes, if you augment the rudder to tighten up the turn. Here's mine at Rocky Mount, NC about ten years ago.

https://youtu.be/eLap8AP27eQ

[JHapprich]

Sexy sub! Handy size!