Beginner question! Sealant!

[redboat219]

Alternative sealing is to use a short length of silicone fuel tubing with an internal diameter slightly smaller than the outside diameter of your drive shaft. Slip the fuel tubing down over your drive shaft then onto the end of the stuffing tube.

[GatoGaterDom]

Gentlemen, answers to questions:

• Vessel uses a solid shaft.
• I have never taken the stuffing tube apart before. Stuffing tube is from RC boat bought years ago and used with no problems.
• I have never added grease to the stuffing tube.

Questions:

• Any particular recommended grease? Where can I get it? Will it need to be reapplied? Time to sit?
• Any recommended silicone fuel tubing? Where to get?
• Can any of these things be bought at an auto supply shop?

Going forward:
I will try both methods simultaneously, then test.

I appreciate the help gentlemen.

[SubICman]

Any waterproof grease will work Hobby stores that deal with rc boats tend to carry small jars of it. It can also be had from places online such as Horizon hobby and Amazon. Other than that, marine grease from the auto store will work. Just undo your coupling and slide the shaft out, coat with the grease and reinsert. You van also try to pack some in the stuffing tube prior to re-inserting. There is no set time for it, it's a lubricant and a water block at the same time. Yes, it will have to be reapplied after some time

Here is one example:
https://www.amainhobbies.com/protek-...xoCF8EQAvD_BwE

[neitosub]

I use white lithium grease from the hardware store auto section. Works really well.

[He Who Shall Not Be Named]

Look under, Flax Packing.

Da

[GatoGaterDom]

Good evening gentlemen.

Adding grease and silicone tubing worked perfectly at keeping the water out. The vessel has now passed a 20min float test, and 10 min full engine power test. The hull is now certifiable water tight.

Another issue has arisen now (all the merrier as the purpose of this project is to learn).

The motor connected to the shaft that had the water issues now gets hot while running, while the motor for the other screw does not. This motor now no longer has the wide range of speed control that it had, requiring that I push the throttle closer to its end ranges to get the screw to turn. Furthermore, sometimes the propeller now seizes, and requires a flick with a finger to get it going.

What could have caused this? Could it be friction from the grease in the shaft? Grease that somehow ended up on/in the motor? Bad wiring?

[SubICman]

The grease shouldn't increase the drag on the screw. Now the silicone tubing will cause binding. That method isn't my preferred method. Grease on the motor will not effect anything, Grease in the motor may cause overheating, but binding not likely.

[GatoGaterDom]

I first looked at the tubing, so I tested without it and learned two things:

1. The grease works perfectly on its own at keeping water out.

2. The tubing was not causing the overheating and binding, as the motor still seizes and gets very hot.

Any ideas? And to rule out the grease in the motor, how can I clean it out?

Dom

[SubICman]

Flush it with >90% Isopropyl Alcohol. This will require you to remove it from the model. Most hobby motors are difficult to disassembly, so do the best you can through the air vents

[redboat219]

Either the old motor's shaft is rusted or old grease inside it has hardened causing binding. Just swap it out with a fresh one (motor).

[GatoGaterDom]

Cleaned both out with 91% isopropyl alcohol. Slight improvement but still not where it was.

Looking online for a small electric motor now. The ones I have are 1.25”x1”, or 3.175cm X 2.54cm.

I do not mind if the replacement motors are slightly slower. The ones I have used are too fast for the scale.

Recommended sources for replacement motors? Recommended specs?

[redboat219]

Any photos of the motors?

[GatoGaterDom]

[redboat219]

[redboat219]

It's one of those toy warships like this.

Nonproportional throttle with differential steering. Stuffing tube doesn't have bushings at the ends to act as stand off bearings that also help contain the grease.

Personally I would rip the old stuff out except for the stuffing tube which you already JBWelded in place and get new motors, a 9gm servo for the rudder, a brushed motor esc, 7.2v lipo, and a 2-3channel 2.4ghz radio.

something like this,