Scale Ship Oscar 2

[ericpw8818]

Re: Scale Ship Oscar 2

Greenman,

I am building the Oscar as well. I am using the same indexing lip up forward as you, but I am installing locating pins ( six of them ) at each brace/bulkhead. These pins should keep the top
half in place and offer some sort of "shape" holding effect. I will post pics when I get my camera back.

Eric

[greenman407]

Re: Scale Ship Oscar 2

Boss subfixer , I really like your avatar and your signature!

[greenman407]

Re: Scale Ship Oscar 2

Hello Eric, We have talked on this forum before and by email. Thanks for your input! Somehow I was under the impression that you had sold your Oscar. Glad to see that you still have it. We live very close. We should meet and swap sub Ideas.

[boss subfixer]

Re: Scale Ship Oscar 2

Boss subfixer , I really like your avatar and your signature!

Thanks, I like to keep things on the humorous side.

[greenman407]

Re: Scale Ship Oscar 2

Recent update. Since it was soooo much fun drilling and fileing(spelling) out the scuppers or vents or whateveryouwanna callems on the upper hull It dawned on me that the same thing would be necessary on the bottom hull. Except much more.




Actually its not that bad. I suspect however that the brass detail screens that were provided to go over them would look good but would actually hinder the water flow in and out of the boat. So they will probably get left off of the sub. The ones on the upper hull will probably get put on as they are bigger and less restrictive. WE will see. I am not alone in feeling this way. My goal is opposite on this boat than it was on my first two boats. This time im going to get it in the water first and worry about paint and detailing later.After installing the plastic lip on the lower hull it needed to have the excess epoxy cut out of the joint so that a nice square corner would allow better matchup of lower and upper halves. Careful! Careful! Dont muck it up.

Here is a view from inside. YOU ARE THERE!!!

Its important as I said before to locate your frames in between holes where possible or you will have this.

Holes going right into your frames Too late now. Ohh youll never see it anyhow.... i hope.
Im sorry, I dont know how to go back and insert images in the text that I forgot so Ill just tack it on to the end. here is a shot of the afformentioed screens that I feel are too small

[greenman407]

Re: Scale Ship Oscar 2

Take a look at this!


As you can see, a gap between the upper and lower hulls but only here at the back on one side. Everywhere else is fine. Now watch what happens when I put a little pressure on it with my hand. WALLAH!!! It disappears like magic.

I dont think that Im even going to attempt to do anything about it. Where the top hull joins the stern section Im going to install two screws anyway. Thatll pull it together and solve da... problem.
Now on to udder stuff. After you guys recommended that I put some frames in the upper hull I set out to do just that.



After marking the areas that I wanted to support I employed a little known but highly effective means of determining the exact shape of the frame at each location. Its called the farm boy method. Observe! Measure across the width of the hull at that point. Then measure how deep you want it to be. Cut a piece of plastic that size in a rectangular shape. Lower it into the hull to get a feel for how much material you will need to remove. Take it out and go to your trusty belt sander or table mounted sander and start by rounding the corners, in this case because of the shape of the hull. Then try it and see how it fits. Then take off some more and put it back in and check it.If you go too far, stop and take that frame and trace around it on new material noting your error and try again. After a while youll pick up on it and each frame will go a little faster. Thats why I call it the farm boy method as you make due with what you have. You dont employ mold release and squirt in foam or wax or cardboard or any of such high technology. Oh yeah , here I am rambling and I almost forgot. Dont forget about cutting in a radius where the frame meets the hull to allow air to move past the frames and not get bunched up. Also measure the distance between the top of the wtc and the upper hull so that you can cut in a relief as you see here for clearance. Seeya

[greenman407]

Re: Scale Ship Oscar 2

An Epic moment has arrived!!! Its time to mount the sail!!! Are you ready? Are you sure? OK!


I thought it would be sometime before I reached this moment but here it is.


A different angle on the bow

And finally a closeup. I am happy with the way it hugs the hull with no gaps. How did I do it?

I started with some 1/4" brass flat bar, measured the spot in the sail on each end that I wanted to use as a attachment point. At that point I took a measurment and after adding a half inch on each end cut it and bent a leg on each side. Then putting it in a vise and using some tools for motivational purposes I shaped it to fit the contours of the sail at that point. Then I drilled holes in the side for better attachment strength. Then I drilled and taped a 6-32 screw hole in it and heavily CAed it in place as you can see here.


Then after the CA dries you can safely measure your holes and transfer them to your model and drill them out and there you go.

[greenman407]

Re: Scale Ship Oscar 2

To get the air out of the hull in the area of the sail I drilled some 5/16" holes under the sail area.

[greenman407]

Re: Scale Ship Oscar 2

Ohhhhhhh! Myyyyyyyyyyyy! Godddddddddddddddddddddd!!! This stupid computer crashed and took everything with it!!! Dont I just love 20th century technology. I lost a lot of pictures of this build. Oh well, lets carry on.


I finally took the plunge and bought one, the infamous Tracker 3. I am hoping that it will end my radio problems. However this radio was sent programmed for 72 mhz so I sent it back to have it modified and at the same time have the right stick changed to friction detent to make operating at periscope depth easier(for me). I prefer the right stick(dive planes) to stay where I put it instead of returning to center.

[greenman407]

Re: Scale Ship Oscar 2


Here you can see me installing the frames in the upper hull. I am using a clamp to hold the hull out to out dimension and then I tack it with ca. Then it is test fit and if ok it is epoxied in place. Sometimes however instead of simply pulling in both sides equally you need to adjust both sides differently. Then when you are finished it will look something like this.

[greenman407]

Re: Scale Ship Oscar 2

Gentlemen, For the sake of variety I turned my attention back to the stern section and the instalation of the rudders and stern planes. First I found out the hard way that the shafts need to be glued into the rudders and planes. If you dont they will slip. I did this by drilling small holes in the planes and rudders and dripping in thin ca.


Also while you are at it cut a small bushing for each shaft out of brass tubing and insert it into the hole that was prevously drilled for it in the hull so that the shafts are held in place and can not flex and give you difficulty of operation.


Oh. And by the way look carefully in the next two pictures for anything funny.




You Cad!!! You Didnt!!! Yep, that is a hole through the top of the stern that I drilled to insert a phillips screw driver through in order to install the screws to hold the bottom rudders. As you might have guessed this was the easiest way to do it and it will be filled in later.

[greenman407]

Re: Scale Ship Oscar 2

Here is a good view of the linkages all hooked up and working


As you can see from this that I so no need to mechanically link the upper and lower rudders together. They will each be operated by a seperate servo and will be adjustable so that if and when they get out of synchronization(spelling) a small allen wrench will bring them back in line.

[greenman407]

Re: Scale Ship Oscar 2

Oh those beautiful propellors! To keep from losing them I put in not one but two stainless set screws of the 6-32 variety. I place the propellors on the shaft after drilling and taping and using a fine tipped pencil I carefully mark through the holes on both sides of the shaft. I then grind flats into the shaft for more holding power.












Notice here that I am paying attention to recessing the shaft in a bit in order to install the attenuaters or what ever yacallums on the end of the props. The will be epoxied on at a future time.

[Rogue Sub]

Re: Scale Ship Oscar 2

Have you considered brazing them to the shafts? I eventually did

[greenman407]

Re: Scale Ship Oscar 2

Looking at the Caswell/Merriman 3.5" sub driver I was concerned about having enough room to fit in all the electronics , so I laid them out roughly where I thought they should go.


Here you can see the three standard size ball bearing Futaba servos. I like to use standard size servos when there is enough room because they use less power than the smaller servos and I find them more reliable. Also shown here is a Dimmension Engineering Sabertooth 2x10rc speed control, A Subtek apc and a Subtek failsafe. Also included is a Dimension Engineering bec to properly handle the Li-po batteries that I will be using.Pictured as well is the Polk Tracker reciever that just arrived.



Oh yes and lets not forget about the Traxxas Waterproff servo that is not really waterproff until after you smear goop all over it. It will be mounted in the upper portion of the bow outside of the WTC to operate the bow planes.