Thunder Tiger Neptune SB-1

[greenman407]

Aquadeep(Dave Santavanez) had one of these 4 or 5 years ago. I watched him dive it blind at Devils Den, straight down all the way to the bottom. The water was like antifreeze in color and you couldnt see a thing. It went all the way to the bottom, probably 50 feet and came straight back up with no problems. He loved it.

[trout]

This is not a speed demon, but I think it is pretty fun! I think for the moment all the major issues are done. Now to customize.....

[trout]

Time for an update.
One of the updates I did was to order the scimitar prop. It did little to increase the speed, Sam was definitely underwhelmed. However, that will be changed soon. A gentleman on another ship site makes props. I gave him the specs I wanted and he is going to make one up for me! Hopefully this one will be smokin' - wait - I don't want that. I have had enough of smoking electronics already! All joking aside, this should help. I will post more when it comes in!
The past two times I have taken the sub out, it had funny responses. The last time, after 10-15 seconds immediately went to safety mode and emptied bladder (just typing that makes me need to go). It turns out the lead acid battery died.

I know a LiPo can be put in, but you need to adjust the cut-off with a variable power supply that I do not own. So, talking to Will Oudmayer, who modified his Neptune, he suggested using NiMH. That way the cut-off levels are not too far off and it will be a drop-in replacement (with an adjustment for weight).
I took to finding a supplier that would customize a pack. A online company had a 4/3 A 12v 3800 mA battery for ~$40. That fit the budget. I ordered it and when it came in it was sent as 7/5 A.

Unfortunately, 7/5 is a little too large. The vendor when I tried to call would not hear of it claiming it is the same as 4/3. After I explained the web and my receipt said 4/3, he changed his web page and added it is the same as 7/5. I did not want to pay for the return and frankly, did not want another pack from this guy. I chose to make what I had in hand work.

[trout]

The opening for the battery inside will need to be opened.

I attempted to disassemble the end, but silicon was used to help seal the end. It was not budging. So to make the opening larger for the new pack to fit, I used a old trick that I did as a kid. When I made some WWII airplanes, I had to have the enemy shot up. I would take a needle or straight pin and heat it over a candle. Once the needle got hot enough, I would pierce holes to represent damage of bullets (including gruesome blood splatters from the pilot). Anyways, I got a spatula with a wood handle and heated the end up. I was not sure it it was styrene or nylon for the bulkheads in the Neptune, but there is only one way to find out. They acted like styrene. It cut like butter for the most part.

Now there is enough room to slide the battery in.

So weighed the old battery.

Now the new. Added enough lead to closely approximate the original battery.

Placed it on a tray, it is drying overnight. The adventure will continue.

[greenman407]

Hot Digedy Dog! Dont let em get you down. I have found really good success dealing with vendors on EBAY. Since they Must keep there ratings high, they will usually bend over backwards to satisfy the customer. Something to think about Tom. Keep at it Sir! Nice to hear from you.

[trout]

Battery is charged and the hull sealed up just enough to test in the tub.

Let it sit in there for a good half an hour. Did some more filling and expelling the bladder played with thrust. I am thrilled to report, the cylinder is dry.
Before I put on all the parts, I will hopefully have the new prop in. I will report more later.

[greenman407]

Tom, now you have something to play with when you take a Bath. "Rudder Amidships..........Up Periscope!"

[trout]

Tom, now you have something to play with when you take a Bath. "Rudder Amidships..........Up Periscope!"

The thought of it getting caught in the weeds has me shivering. I'll pass.

[greenman407]

You have weeds in your Bath? I didnt see any?

[trout]

Ahhhh, never mind.......
I am excited about this new propellor. I'll share more once it comes in.

[trout]

At a site called War Ships Underway (http://www.wmunderway.8m.com/cgi/yabb2/YaBB.pl) I met this gentleman Keith. He makes props on the side. I heard of others ordering a Raboesch prop, but it seemed small for the shroud. I asked for one made 3 mm larger or 38mm in diameter. Here is what he made:

Next to it is the Scimitar prop you can get for the Neptune. Big difference, huh?

I should have ordered it better because Keith was willing to make it exactly the way I wanted.

Now that it is installed, I will now assemble it back together and test.

[greenman407]

Go Getum Tom. Looking forward to your test results

[trout]

I realized I never updated this with the results!
The sub runs like a champ. I have speed to chase down other subs to photograph and it runs a long time. How long you ask? I do not know, I never timed it over an hour, at least, twice my tax battery died before the sub did. I have replaced the battery in the TX and I just run it or Sam does until he is bored. I have not taken it out because my focus has been the Walrus build, but that is winding down so might need to get some hard numbers.

[MFR1964]

Tom,

A Walrus build?, you've got some pictures?, when this is the dutch Walrus sub, i had the honour in the past to visit one during a tour on the yard during maintenance in drydock.

Manfred.

[trout]

Still have to complete painting and some other details. This sub runs so well.