Seaview

[greenman407]

The Seaview goes in the water tomorrow for a test of the new motors and thrust bearings. I picked up a temp gauge and ill be testing the motors for temp and power fade after a good run at top or near top speed.

[greenman407]

Today was the day. After running for about 45 mins, and pulling it from the water and opening up the Subdriver to take temp readings, I have come to a conclusion. Although big increases and improvements have been achieved, these 12 volt motors are not the answer to this problem. In all fairness to them I was running them at full throttle for a half hour. The temperature buildup was that it got to 140 degrees+ on the motors. That is not sustainable. Im looking for motors that are so efficient, with this package, that the temps will stay at no more than 120 degrees. That with running full throttle, with no cooling. Why so much full throttle? Because this thing is a BARGE in the water. It takes a lot of power to move it. There is a lot of inherit drag in those recessed windows and all the slots on the superstructure. I need a power source that is way overkill, so that its just idling along, so to speak. My new motors are in the works. He emailed me yesterday on the progress. Humor me.

[Peter W]

Mark, I know that my mate, the one building the NR-1 has a similar problem the scale props in the rear planes just aren't going to push it along. He came up with the idea of running a separate, discreet thruster through the back as well. Not sure it will work but it 's a crazy enough idea for at least a ponder on. Other option sounds like cooling.

Oh and don't burn yourself on the motors I am the only idiot allowed to do that.

Peter

[greenman407]

GUESS WHAT I GOT???!!! My two custom wind motors. Designed specifically for my Application. 27 turn, long shaft(1")super magnetized, extreme heat resistant, stand up heat resistant brushes.
However, it seems to me that if you run anything wide open for too long its going to get hot. My next step will be to use the existing Caswell 12 volt motors as they are and change the empellors to the 4 bladed ones. If I can generate some more speed then we can afford to chop the throttles and run at a lower throttle setting. Then we can see if we can keep the motors from overheating.http://www.teambrood.com/store/home.php Eddie does nice work and he keeps in touch during the process with continual updates.

[greenman407]

And another thing. Im thinking seriously about removing the clear windows from the nose and leave the window ports open. It wont look as good but the water will be able to enter the nose without being deflected back out and its associated hydrodynamic drag penalty. What do you think?

[greenman407]

Gentlemen................and I use the term ...........loosely. The next phase was to remove the two bladed empellers and install 4 bladed ones. These are nice bits Dave sent me. What a nice guy! They were, however, larger in diameter and the hub length also was longer, so a bit of backyard machine work was called for. At anyrate....they are going in as we speak. I hope to get a test in this weekend. Im looking for improved thrust numbers. This will tell me that(using the existing motors) the thrust numbers of previous, were limited by RPM capability of the motors@3 to 1 gear ratio and not solely dictated by the motors torque limitations. So the question will remain....Can these motors produce the thrust that I need at a reduced RPM, without overheating? At that point I will know whether or not to upgrade the motors or leave them as they are. Cheerio!

[He Who Shall Not Be Named]

make sure the curved face of the blades point forward.

M

[greenman407]

Yep....Gotcha. This camera angle distorts the view. Its right as is.

[greenman407]

And another thing while Im thinking about it. Those Dumas drive couplers will probably have to go in favor of something more robust. Remember the pictures that I posted of the wear on the old ones?

[greenman407]

Today, I got out the kiddie pool and filled her up for the test. After installing the four bladed empellers, the thrust measurements dropped from 15 ounces down to 12 or 13 ounces. This tells me that we have exceeded the power of the Caswell 12 volt motors. So, now, with our back against the wall, we have little choice but to proceed with motor replacement/upgrade. We will now be installing the new motors and see what we get.
Also, the Subtek APC has bit the dust. Its been acting funny. When you first power it up, it holds the planes perfectly. But after a few minutes the planes slowly creep to a new position way off from where you have it set. So, no 21 gun salute for this thing. Its life was way too short for the money I paid for it. Hopefully, its replacement will demonstrate a greater degree of longevity.

[greenman407]

In order to install the new APC, as has been my recent custom, I put down some bubble wrap first, to try to reduce vibration feedback to the APC. I found out that silicone seal dissolves the bubble wrap into a very hard substance that will Cut you, if you are not careful. That will also transfer vibration, instead of cancel it out, so we dont want that. So, instead of using silicone this time, Im using this stuff(see picture). So , I cut two pieces of bubble wrap and installed them, one on top of the other, and glued them down. Now for the Apc, right on top of this mess.

[greenman407]

Ive got the day off tomorrow. .....Guess what im going to be working on? Ha Ha!

[greenman407]

KO......I mean OK. Tearing it apart again and installing the new motors. The motors req. a 3mm screw. I didnt have any so I used 6/32 last time......I think. At anyrate last time I re threaded the motor screw holes with a tap. I didnt want to do that this time so I was on a hunt for 3mmx.5mmx10mm countersink head screws. No go at Lowes or homey depot so I had to order some good ones. 316 S.S. from Mcmaster&carr. Take a couple of days. Anyway here are a few shots. The armatures are definitely shorter on these 540s compared to the 550s.

[greenman407]

A little here and there. To get the old motors out I have to cut the shaft. This because the brass gears are "sleeve retained" onto the shaft and the only way to get them off is to heat them up. That would ruin my high tech shaft seals. So I cut the shafts just behind the gear, then pull out the motors after de-burring the shaft left sticking out of the motor. Then a propane torch on the gears will cause the epoxy to release. Then, just a matter of cleaning out the old hole and re-sleeve retaining the gears back on. I hit the new motor shafts with the edge of a Dremel blade to rough it up, preceding the application of the Permatex stuff. Works great. I still dont know if the 20 amp Mtronics ESCs will handle the new motors now that I have 4 bladed empellors in place. We may be looking at making a swap. Ive got two 40 amp Jomars on standby. If I dont need them they will go into the Portofino, thats in drydock awaiting modifications.

[greenman407]

This is the 15th visit to the Drydocks for this Rick Teskey/D.Merriman/Mark Green Seaview. Its been an educational tool for me in my ever continuing Quest to DOMINATE the little pond down in Clearwater, Florida 33755. If I were to add up the tab of my expenditures over the years for my Entertainment in this Hobby................I think I would have to be committed to Hospice for daily care. As it is I am afraid to think about it. But it keeps me entertained..................legally.