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**greenman407** · 01-03-2015, 08:28 PM

I got some paint on it.today.

**greenman407** · 01-10-2015, 08:32 PM

IM not happy at all! If youll recall, months ago I painted a pretty decent coat of black on the upper hull. When I pulled it out today to do some detail work, I couldnt beleive my eyes. The joint where you have to glue the hulls two upper pieces together to make one? Well, it seems that the model airplane glue that I used on the joint(from below) didnt know when to stop. It swelled the plastic above it. So now I have to cut that swelled area down with the dremel and sand and re-apply filler. RATS!!!

**greenman407** · 01-10-2015, 08:35 PM

Oh well....on a happier note I completed the new motor install and did some touch up work on the colonial red paint on the bottom hull

**He Who Shall Not Be Named** · 01-10-2015, 08:39 PM

... we hav'n fun yet?

M

**greenman407** · 01-17-2015, 11:10 PM

I beg to report my meager progress since my last posting. As you will recall, the red that I painted on the lower section "crazed" and I made numerous attempts at wet sanding and repainting. When you wet sand you dull the paint. Since I did this several times, I reached the point of sanding only the offending areas. This left bright shiny paint in some areas and dull ,flat paint in others. So I sprayed all the red on the lower hull with clear gloss polyurethane to even out the finish. After more than enough drying time has elapsed, I will then spray it with the same product manfacturer, except this time a clear satin to tone it down.
At the same time I got in some sanding on the dreaded upper hulls center seam debacle that I reported last week.

**greenman407** · 01-18-2015, 08:22 PM

I did a little more sanding today. Ill be putting another coat of black on it next weekend.

**greenman407** · 01-24-2015, 08:26 PM

I finished the sanding on the BooBoo. Now to restore the scum line that runs thru it. Ive got a stainless straight edge with sandpaper glued to the bottom of it to help it "stick" where I put it during the scribing process. Its been my experience that when you try to scribe thru Evercoat or Bondo ,the scribing tool chips the softer filler material and you have a bad scribe job. So I did two things to help prevent that. One....I coated the area with thin CA and let it soak in. Then sanded it down. I also used a razor saws tip end to do the scribing by placing the saw at a low angle to the work and pulling the saw backwards along the edge of the straight edge positioned along the scum line. It worked perfect. No chipped edges. I installed some decals to the rudder, but its too cold tonight to apply any paint. Ill probably have to wait until next weekend. We are getting closer.

**greenman407** · 02-08-2015, 08:15 PM

To help this boat take advantage of the upgraded motor install, I am adding more weight to the keel. It can only help keep it from rolling during power application. Since you have to add corresponding foam to the boat to achieve neutral buoyancy, the added weight wont cause additional drag. But, it will increase stability. Right Dave?

**He Who Shall Not Be Named** · 02-08-2015, 10:29 PM

Glug, glug ... er ... right you are, Mark. Glug, glug.

M

**greenman407** · 02-09-2015, 07:03 PM

Two things
(1) Your just playing with me.
(2) A wet hulled submarine gets very heavy once submerged. By adding foam at the waterline to achieve neutral buoyancy, you have negated the extra weight that you have added in the keel by displacing some of the water(and its weight) that is up higher. The end result is the same except you now have more weight lower in the hull for more stability. You still flood the ballast tank (submerge) with 1/2" to 1" of the sail sticking out of the water. So then, whats the DANGER in that?

**He Who Shall Not Be Named** · 02-09-2015, 07:17 PM

Originally posted by greenman407

Two things
(1) Your just playing with me.
(2) A wet hulled submarine gets very heavy once submerged. By adding foam at the waterline to achieve neutral buoyancy, you have negated the extra weight that you have added in the keel by displacing some of the water(and its weight) that is up higher. The end result is the same except you now have more weight lower in the hull for more stability. You still flood the ballast tank (submerge) with 1/2" to 1" of the sail sticking out of the water. So then, whats the DANGER in that?

You have it right -- the objective is to increase the mass to increase the force of gravity, and to cram in enough displacing foam to produce a buoyant force that cancels the increased gravity force. Center of gravity low, center of buoyancy high produces a taller metacentric height, which is the moment arm that rights the sub statically about the roll (and to a much lesser degree) pitch axis when the c.g and c.b. are displaced from their proper vertical orientation to one another. The vehicle is statically stable when the c.g is directly under the c.b. Anything else, a moment is produced to put the c.g. and c.b. back into vertical alignment.

(The glug, glug sounds was me oinking down those Diet Mountain Dew's you sent me -- the source of confusion I bet).

M

**greenman407** · 02-09-2015, 07:59 PM

Oh, Gotcha. Bonappetite! (spelling)

**greenman407** · 02-15-2015, 10:12 PM

Today I got the sonar dome squirted Charcoal Grey. Then I need to do the International Orange on the Buoys and the silver on the vents. Then LEDs in the sail.