Revell Type VII Build advice

[H2Ohaze]

On my Holland, the motor is also too fast for good operation. I use a Futaba 9C to control it now, so I don't know if the WFLY can be made to mix throttle to throttle, but I have three mixes set this way : master and slave are both throttle. I use one 3 pos and one 2 pos switch.

This gives me six different throttle behaviors:
1) Full speed ahead and reverse as originally set up on the Viper 10 ESC.
2) Full lockout; prop will not spin in either direction no matter what position stick is bumped to. Great for panic cutting power to prop suddenly to locate a lost sub with slight + buoyancy.
3) Very slow RPM forward cruise control constant speed, regardless of stick position.
4) Throttle stick speed goes from zero to moderate forward only, no reverse. Stick pos 0 to 100%
5) Throttle stick speed from moderate reverse to moderate forward, with zero at 50% (middle).
6) A version of #1, with a little less forward power.

I also have a switch that mixes channel 4 to itself. This locks out my ballast pump. On the VIIC, it would prevent accidental vent or blow.

I've only been experimenting with this setup recently, but I think I like it. The switches are on right, so I can adjust throttle with left hand as switch state changes. I use #4 85 % of the time.

[Avera]

Does anyone know what is the minimum voltage to run the motors? I was thinking of adding a series of resistors to reduce the voltage going to the motors to a minimum level maybe as little a 3 volts. Just thinking out loud.

I have the 6 channel WFly transmitter and not sure if I can dial down have a throttle mix.

[He Who Shall Not Be Named]

Does anyone know what is the minimum voltage to run the motors? I was thinking of adding a series of resistors to reduce the voltage going to the motors to a minimum level maybe as little a 3 volts. Just thinking out loud.

I have the 6 channel WFly transmitter and not sure if I can dial down have a throttle mix.

Easy enough to set the end-points with a dumb-ass transmitter. But, you'll do it at the ESC. During MTronik's ESC set-up, only move the throttle stick up and down a bit when setting up the ESC's responce logic. Go to MTronik's site to get details on the process.

Don't put a series resistor in series between the ESC and the motors -- what a waste of energy!

You people!

David

[Avera]

I know I am getting close, but I have another question regarding the dog-bone couplers. Do you guys attach one end of the couplers to either the shaft or the motor couplers? If so with what?

Trying to install the SD while aligning the two dog-bones into both couplers at the same time is hard. One or the other dog-bones drops; I don't have enough hands. I was thinking that the dog-bones could somehow be already attached or held in place by one of the couplers (the motor coupler preferably) with some sort of light or sticky adhensive as they are loosely held in the couplers and fall out. Then all I would have to do as I slide in the SD is rotate the props by hand to align it.

[Scott T]

Here is something to try: take a rubber band and put it over the shaft and place the dog bone
in it as you spread the shaft from the dogbone twist the rubber band.
You probably will want to remove it before running though. Scissors or a sharp knife.

Or mister D can invent some klik-on style dogbones!


Scott T

[He Who Shall Not Be Named]

I know I am getting close, but I have another question regarding the dog-bone couplers. Do you guys attach one end of the couplers to either the shaft or the motor couplers? If so with what?

Trying to install the SD while aligning the two dog-bones into both couplers at the same time is hard. One or the other dog-bones drops; I don't have enough hands. I was thinking that the dog-bones could somehow be already attached or held in place by one of the couplers (the motor coupler preferably) with some sort of light or sticky adhensive as they are loosely held in the couplers and fall out. Then all I would have to do as I slide in the SD is rotate the props by hand to align it.

You are on the money: I glue the dog-bone to the propeller end of the running gear with RTV. It hold the dog bone, but gives enough to accommodate the off-center turning when made up to the SD.

I have employed spring-loaded dog-bone as well.

[Avera]

Too bad there is not a knuckle (universal joint) type of coupler with a built in dog-bone that can be lengthen or shorten depending on application. I am sure these exist in the RC Boat world, just need to find them.

[Avera]

Did a trim test today, the boat is still too heavy and will need to add more foam and probably reduce some of the weight as a lot of foam is still needed and space is getting tight.

Two new problems came up:

1) The ballast servo is getting intermittent control. I think I need to replace the servo lead connector with a better and longer extension. The lead on that servo is way too short and I had to add a 3" extension. When the electronic compartment is open and there is no compression of wires, the ballast works fine, but when I squish everything into the tube, I get this problem.

2) Second problem a bit more serious is the stern plane bell crank, there is too much play with the rear plane thereby not giving me enough up or down movement that coupled with the short servo throw essentially leaves the rear plane useless. It could work somewhat if I can figure how to get the servo to throw a greater movement (I have already tried the trim control). This needs some sort of leverage to push the rod further back and pull further forward.

Contemplating pulling apart the rear planes and bashing down more the bell crank (although I think the metal is too soft). Just not sure if I want to tempt fate and break the plastic connecting guards for lack of the correct term (the little thin outside plastic part guiding the planes (I know it is not needed).

[He Who Shall Not Be Named]

Did a trim test today, the boat is still too heavy and will need to add more foam and probably reduce some of the weight as a lot of foam is still needed and space is getting tight.

Two new problems came up:

1) The ballast servo is getting intermittent control. I think I need to replace the servo lead connector with a better and longer extension. The lead on that servo is way too short and I had to add a 3" extension. When the electronic compartment is open and there is no compression of wires, the ballast works fine, but when I squish everything into the tube, I get this problem.

2) Second problem a bit more serious is the stern plane bell crank, there is too much play with the rear plane thereby not giving me enough up or down movement that coupled with the short servo throw essentially leaves the rear plane useless. It could work somewhat if I can figure how to get the servo to throw a greater movement (I have already tried the trim control). This needs some sort of leverage to push the rod further back and pull further forward.

Contemplating pulling apart the rear planes and bashing down more the bell crank (although I think the metal is too soft). Just not sure if I want to tempt fate and break the plastic connecting guards for lack of the correct term (the little thin outside plastic part guiding the planes (I know it is not needed).

You're earlier ***** was about spring-loaded dog-bones. Try these on for size:

You're on the right track with the glitching ballast sub-system servo -- put that extension in there and see if the problem goes away.

As to the stern plane. Don't sweat it, the white-metal can take the tightening-of-the-hole hammer blows. Just be careful as you pull the plastic bearing pin retainer out of the way. Lay off the Caffeine as you do this work, that's all.

David

[Avera]

Okay, the stern plane issue appears resolved. I was able to successfully take it apart without breaking anything; good thing I did not get my daily does of Cuban coffee otherwise it might have been a different ending.

I added some more foam and remove a bit of the weight mainly from the stern area as that is the heaviest part requiring the most foam.

We will see later this week when everything has dried and I can get a bettor extension cable from my LHS.

Once I can get past the tub test, its a trip to the community pool.

Andrew

[He Who Shall Not Be Named]

Almost there pal.

David

[Avera]

You got to love this hobby. I just ran into another minor problem. I think the ballast servo is shot. I noticed crystalline looking material on the plastic surface and it is not operating. Not 100% sure if it looked that way before. No water got in and all the other circuits works without an issue. I tried it with a new extension cord and nothing. I wired it directly to the RX (with and without the extension) and nothing. I tried the extension on a different servo and it works. Need to get a replacement servo and hope it is easy to replace. Looks like there is only two screws holding the mounting band. The trick will be to connect the servo arm to the push rod.

Any suggestions or tips?

[trout]

I ended up doing mine,twice. http://forum.sub-driver.com/showthre...art-duex/page3 here is what I did. A small amount of CA on the screw with screwdriver held it in place until I got the screw in position and started it going in.

[He Who Shall Not Be Named]

That's how I do it, Shane. Crystals inside the servo case? Water maybe. Any flooding casualties you want to admit to (aiming bright lamp in your face). You remove the servo and push-rod as a unit. Install it the same way. Tricky operation.

Frustrating, isn't it?!....

David

[Avera]

Any suggestions where I can buy another servo?

As for water, I have only tested it 3 times in my tub. I have not noticed any water in either WT compartment; although not impossible for a drop or two to have entered when opening as the some of the other electronics would have been damage had there benn a bit more water given the height of the servo mount. However, there is a lingering electrical smell in the compartment. I think tugging on the servo leads during the adding/removal of the electronics (because it was short relative to the depth in the tube), I must have pulled the wires from its internal attachment points possibly creating a short.