Scale Ship Oscar 2

[greenman407]

Re: Scale Ship Oscar 2

Into the water she went on Saturday afternoon. The turning radius is now much improved. It is now 15 ft. radius with rudders hard over. I can get it down to ten ft. by stopping the inside prop and speeding up the outside prop. This is submerged turning performance. Next time out I will take note of surfaced turning performance. I need to retrim the boat as the nose is running light and makes maintaining periscope depth difficult. When I pulled the boat out of the water I was surprised at how much water was inside the subdriver dry space, about a half inch. When I got home later I put it in the bathtub and removed the valve core from the shrader valve, slid on a piece of hose and blew into it. Bubbles came out of one of the four pushrod seals. So today I will order a couple from Caswell. Im also not happy with the new ballast system modifacations so I will be concentrating on that as well. I should have it back in the water in a couple of weeks. Cheers!

[greenman407]

Re: Scale Ship Oscar 2

As I was running submerged A dinosaur or the Loch ness monster came up right next to the Oscar and caused us to go to Red alert. It was blindingly fast. Efforts to get photographic evidence was challenging but I got it!

Its a little fuzzy but you get the picture.(punn) I believe its called a Cormorant. Its like a little submarine. It sticks up its periscope, looks around and then its gone, only to resurface again in a different spot. Too fast and unpredictable to use a torpedo on. I thought about using the deck gun but then I remembered that I DONT HAVE ONE! So I let it live.

[greenman407]

Re: Scale Ship Oscar 2

Gantu just posted these on "Awesome sub pictues" under General. They are so good that I wanted them on my builders thread also.


Look at all the detail thru the torp tube openings! How about all that missle tube detail? Thats what Im talken bout!!!















OOOOPPPS! a little bit off subject.

[greenman407]

Re: Scale Ship Oscar 2

Just a little update. The offending pushrod seals are 3/8" in dia. and 7/8" long for a 1/16" pushrod. I have been informed that they are no longer available. What is available are the 1/4" od ones. I will hit the hobbie store today and buy a length of plastic pipe that has a 3/8" od and a 1/4" id and use a piece of that to bush the new pushrod seal. Gotta have it!

[greenman407]

Re: Scale Ship Oscar 2

It happened a while back but when I was working on the rudders , drilling and tapping them for set screws ,as you machine and drill on them the material that these control surfaces are made of give off extra strong odors. Its like cutting into an orange, very strong. They must be made of some weird stuff!

[Rogue Sub]

Re: Scale Ship Oscar 2

Polyester resin probably. I have found the older they get the worse the smell. Of course it might have just been the dog!

[greenman407]

Re: Scale Ship Oscar 2

Ok , got everything in working order and back together. This weekend coming up will be a testing weekend to get it back dialed in. I drilled out the vent hole to 3/16" and reset the rubber valve and siliconed it in place. It should translate into faster flooding of the ballast tank which up to now has been agonizingly slow. Dave Merriman has plans to introduce a 1/4" vent valve at some point. The next stop will be Blue springs on Oct. 12th which feeds the St. Johns river. The water is deep and bathwater clear. To make it a success we need reasonable amounts of sunshine and NO swimmers to muck things up by constantly getting in the way! Ill make a full report the day following.

[greenman407]

Re: Scale Ship Oscar 2

There wont be any need for a 1/4" vent valve believe me. It now slips under the waves in less than 30 seconds if you hold down on the lever. More judicous use of it will be in order if you want scale like dives. Drilling out the vent valve to 3/16" is more than satisfactory.

[greenman407]

Re: Scale Ship Oscar 2

http://s122.photobucket.com/albums/o254 ... I_0002.mp4
Here is a video that is mainly of Al Nuci 66" Nautilus and its posted in the video part of this forum. I am linking it to the Oscar build because at the start of it you will see my Oscar in the background going from left to right in a shallow dive slowly ascending.

[greenman407]

Re: Scale Ship Oscar 2

Here are a couple of pictures from the same event. It looks like the Oscar is buried in grass but its actually about 6 ft. deeper than the sub.

[greenman407]

Re: Scale Ship Oscar 2

I had a few leaks in my 3.5 Subdriver. A few that I have already mentioned but then a new one cropped up. A leak at the ballast tank bulkhead. If you look at the foot print of the o ring you could see an area about a inch long that it didnt look like it was touching the cyl. at all. Some people( myself included) have expressed concern over pulling one of these things apart. Then I thought , well it aint nothen but a thang( as they say in the hood). So , since the cyl. is a 3.5 on the outside it measures 3.25 on the inside. A piece of 2.5" steel pipe from work measures 2 7/8" on the outside, just about perfect. So I cut a piece 25" long.


Im going to use this piece of pipe to push the bulkhead out of the cyl. for maint. You can see here a notch that I cut in the end of the pipe with a torch to provide clearance for a modifacation that I had made. The micro servo that moves the ballast tank vent and blow mech. was giving me trouble , so I replaced it with a standard size servo and a servo horn that was slotted to a much lesser degree than the original one. It works great but its in the way, thus the notch.

So first you remove the five screws that hold in the bulk head and take loose the copper propel holding tank. Then I pulled out the snort manifold and took the vent off the top. The screw that you would then next see that pushes up on the rubber vent valve must be removed. Take note of its position verses the top of the cyl. and take it out, so that you know about where to put it back later.Placing the pipe vertically on a table lower the cyl. down over it and push. The square end of the pipe will keep the bulkhead straight as you push it out.



To put it back you do just the reverse. Be sure to lubricate the oring first with silicone grease.



Kevin Price at Rogue subworks recommended using trim tape to put down in the bottom of the groove. I put in about 6 full wraps and then replaced the oring. When installing be careful to assist the oring to stay in its groove when trying to get it started in the cyl. Push it carefully back in taking care to make small rotational adjustments as you slowly slide it in to get your screw holes to line up when you get back to its original position. Then just hook everything back up. A 3.5 ' cyl. is a whole lot easier to do than one of the smaller ones in my opinion because I can get my hand up inside of it and that helps. You can see here the new pushrod seals that I had to bush with a small piece of plastic pipe.

[Rogue Sub]

Re: Scale Ship Oscar 2

Well yes that thin trim tape can be used if you need it a little bit tighter but, 6 wraps is a little excessive for my taste. It really is just a band aid fix to the real problem. The best solution would be a proper fitting O ring and groove.

[Guest]

Re: Scale Ship Oscar 2

Marko. Master bulkhead remover,

Nice work!, looks like the operation was a success, let us know when you have completed water testing of the cylinder, I may have need to borrow that tool one day.
I once had a similar issue with a 2.5 cylinder

[greenman407]

Re: Scale Ship Oscar 2

Kevin, Thanks but a proper fitting o ring and groove would mean the purchase and install of a whole new ballast tank bulkhead. My thought is this will be the experiment for how long this fix will last. As long as the trim tape doesnt come out we should be good.

[greenman407]

Re: Scale Ship Oscar 2

Will do Al! I can pretty much get what ever size pipe we need for what ever size cyl. I will test this weekend and get the Oscar back out in the water.