LA Class Scratch build using arduino and pistons

[johnredearth]

Still on holidays, and still thinking.
One thing that bothers me about the LA sub is the lack of traction on the rudder, which sits before the prop. (Everything is before the prop)
I note that when I built the Nautilus and put it in the water for the first time I put the rudder hard over and it went straight ahead. Not having output from a prop to flow over a rudder really reduces its useability, and that is particularly the case for slow ahead situations. With the Nautilus I found that if the boat was at speed it would maneuvre with the rudder, but it was a delayed process. It seems as though the very act of turning began a moment of turning which could be built upon. I have to say though that in the world of small ponds, and other boaters around who do not necessarily see a sleek black hull down low on the water it is a nightmare. Subs clearly used tugs and other ships to assist them and are simply not thought of as requiring maneuverability. None of this works for a model.
So with the Nautlilus I added a piece of clear acrylic to the lower portion of the rudder that has a little ‘turn up’ to allow it to function in the wake of the twin props. No-one notices it, and I have the capacity to turn, really well.
The LA is very different however. There is no way I can do what I did with the Nautilus so after considerable thought, and the necessity of wanting to manoeuvre the boat I have decided to break the rules of the model and add a bow thruster.
The first thing to consider is how to control it. So I have decided to use the ‘knob’ that now controls compass headings to turn on the bow thrusters. This means that when I want I can turn it on, and through a relay, power the bow thruster. The thruster itself will be a brushless motor with speed controller, attached directly to the ‘rudder’ channel. Thus when the boat is still I can turn this on and turning the rudder will have the effect of incrementally increasing power to the bow thruster.
So the next question is ‘how’ to build a bow thruster. It is possible to get them on the net for less than $60 or so, but they are brushed and this clearly does not include a speed controller. I want a speed controller as the power will be on/off and will need to be managed, plus much better control. Also a brushless unit with speed controller is cheap and is really where the world is now.
But, I am a scratchbuilder,
so the time has come to make my own. My experience in building pumps for the U-boat and Nautilus will come in well here and I know I can build a very powerful and effective bow thruster. So more on that as we go forward. Come to think of it, as this one will sit in the water it will need to be sealed. A similar model, inside a surface boat, will be much much easier to build and adapt. The advantage of going brushless is that the motors are very easy to modify with a longer shaft. The brushed motors have fixed shafts that you have to work around, or to. Plus, a brushless motor will be so small!
Lots more to come on this. I have spare small brushless and I need to test it out with a 3s lipo. Lots of fun when I get home.
Blog on http://www.scratchbuildwithjohn.com/...ine-update-10/
Cheers
John

[johnredearth]

The build of the Los Angeles is coming along, and most recently I built the main WTC with the seals and end caps, and also the bow thrusters for the bow of the boat. But I have to digress and tell you about another problem I was confronted with which I have not addressed properly before concerning submarines.

Radio Control

The problem all sub modellers face is that the RC that is needed for subs is not easy to get. There are different rules /laws in different countries re RC frequencies, but the simple truth is that only low frequencies work under water, and only low frequencies can be used with subs. In Australia that is 36 MHZ. In other countries the frequencies run from 29-72 and there are probably variations within that grouping.

The issue is the discovery of 2.4GHZ. Nearly everyone has one now. They don’t require discreet frequencies, and they work flawlessly, and they are cheap and they dominate the hobby, particularly for planes and everything above the water line. In the days before 2.4GHZ, modelers would gather to share their hobby, but would have to use ‘peg boards’ or similar to make sure that frequencies were not clashing. For example in the 36MHZ range there are 20-30 sub frequencies. If you turned on a transmitter when someone else was using that frequency there would be a control problem, and with planes it would be a very nasty and fast end. I can’t even imagine how many flyers have come to blows over this. Or the occasional eye skewered by a crashing plane!

The 2.4GHZ eliminates this by ‘frequency hopping’ and means that no clashes occur. As a result the old 36mhz is no longer used at all and no-one makes them. The sub community is not big enough to attract the investment of building old units.

So, many years ago before 2.4 I bought a 36 MHZ radio and three receivers that had 7 channels specifically for subs. (I still have this now and if anyone wants it let me know). When I build the Nautilus however I wanted to do more but by this time everything was 2.4GHZ. So I searched ebay and magically found a guy (old airplane guy) who had a 9CAP 9 channel Futaba with two 9 channel receivers at 36MHZ. I have to say this was purely good luck, but there are people with these on the shelf that are not being used anymore, but this also highlights the problems for the submariner. Namely, you have to look around second hand. So I used the two receivers and built them into my two subs and they work beautifully.

Then comes the LA. So I put a permanent search on Ebay for a 9 channel receiver and suddenly got a bite, for the USA of all places. (They don’t use 36 MHZ in the US). I tried it out and it worked nicely, until last week. It died when I was trying out the brushless bow thrusters. I am certain this had nothing to do with the bow thrusters. Anyway, it came back to life, then died again. Needless to say even if it comes back to life, I can’t use it in a sub!

So I took it to the local model shop. The young guy there looked at it and waggled his eyebrows and sideburns. This was clearly a dinosaur from the ancient past. He said, I would buy another one and throw this away. That was helpful but also not quite that helpful as there is no-where to go to buy these. There is a Hong Kong on line shop that seems to sell a range of Futaba receivers including old ones, even ones at 36MHZ, and nothing with 9 channel.

So I went to my favourite place on the facebook page ‘Dive in to submarines’ and asked the brains trust there.

The result is I am going to try something new, that I have read about at other times but as I smugly had my equipment I have not thought of using. This is called 433 MHZ LRS system. This system is close to a radio ham technology, modernised and used for ultra long distance drones. It is a higher frequency but has channel hopping and from all experiences thus far works very well with subs. Is 433 MHZ OK in Australia? Perhaps. I find the best way to deal with this question is not to ask.

The stuff I have seen on this describing how to use it was very complex and I never delved into it, but the gurus (Tim and Andrew) gave me a pointer so I purchased a receiver and a unit for my old 9CAP for $50 Aus, including shipping. Amazing value. So when I get it, I will delve into the dark arts and produce a video on it that is hopefully a tail of simplicity and success. Story of my life.. mm.
So while I wait, I will get on with the hull.

BTW the bow thruster works amazingly. The full build description is found on my LA page.

BTW the blog and pics are here

[johnredearth]

Main WTC
I noted that one of the reasons I wanted to build the LA was to use a classic design of using two pistons. This is the tried and true method used by Engle, and is relatively simple and reliable. The difference is that I am going to scratch build the pistons, and I am adding the laser sensors to measure where they are and get an arduino to automate the whole process.
But, despite that, I have my own quirks. I built, as I have before, a discrete motor room, with the motor, speed controller and two servos in it, to control the rudder and the hydroplanes. The main WTC therefore does not require these and can be built as a unit without them. I also like to build the end cap for the motor room into the hull, (removable with a bolt) and connect the working gear onto it. The WTC cover is a sleeve that fits over it and is removed between sails for ‘airing.’ This is my design and is a bit different.
So the time has come now to build the WTC, and I am keeping the ideas I thought about in the blog ...This means I am going to have three spaces. The central space is the main area for electronics and also holds two lipos. This by definition (lipos are tricky) means that it has to be accessible and the lipos need to be easy to get out for charging. The two other parts of the WTC need joiners and each will have a bulkhead glued in that the gear box and motor drive can be connected to. The other side of the bulkhead is the piston. So the two connectors are the issue and I decided to make a two way connector for the bow section, so that I can remove the piston section easily, but also remove the other side of the connector from the central section so I can get full access, and also therefore full use of the space inside.
However I decided that the connector for the other end of the central section could be glued onto the central section, and only be ‘breakable’ to remove the piston section. This is so that I can build into the central section the horizontal bulkheads for mounting the electronics, and also to make a fixed space for the lipos. Of course the structure I build will be screwed onto the joiner, allowing me to remove these parts as I wish. The other issue is that I need an exit point for wires, and this structure will give me more room to have a ‘wired out’ section in the joiner. (The bow one has a very thin section as I use all the meat of the joiner for the two o rings). There is only one on the stern section.
So with the structure in mind and sorted I then had to decide on dimensions. This involved using the ‘rule of thumb’ method of having 25-35% of the total WTC hull, including the motor room, for ballast. I have made full video on all of this and it can be found here!
So I made the connectors, cut the WTC material with the dremmel, glued in the piston bulkheads. (Although before gluing these in I had to make a removable framework to hold the piston sensors. To do this I used my favourite material ‘acrylic’.) That done I completed the joiners and tested them with o rings.
Then I added two disks for and aft that fit across the entire inner part of the boat, with cut outs that fit the WTC. This has purposes. One to enable me to bolt the system together to stop it coming apart due to the pressure of two pistons, two to enable me to fix the whole system into the hull, and third to provide wholes in the top I can screw the top of the boat to.

See blog


So following on from last week, I added the o’rings to the WTC connectors and mounted the system in the hull. This was in interesting process in itself.
After I ‘sat’ it in, it was a matter of standing back and seeing how it looked by eye. It needs to be central, but the LA does have a ‘bow up’ stance when surfaced so a little shift toward the bow is quite reasonable. I am not too worried about this as when I get the boat going finally I will set the pistons to fully dive, or at least to where I want neutral buoyancy, and then add ballast to the hull till I get it sitting perfectly using mechanical adjustments to the right spot; namely 10 Centimetres under the water. Only when that is right will I empty the pistons and see how it is sitting above the water, and I can then adjust the pistons (remember the laser control system) to get it sitting exactly how I want it, and then locking the pistons in to that setting.
But now it is a pretty much course adjustment. We have way to go. So I set it to the best spot and then heated up two pieces of acrylic to act as fasteners. I wanted them to be 90 degree brackets. Using a heat with acrylic is easy and results in a light, and strong bracket. I added to the bow bracket a screw that points to the front of the WTC holder and then drilled my WTC holder to accept it as a slot. I used some fibreglass filler on the bow bracket, and mated up the WTC and holder to it and let it dry. The stern bracket was screwed onto the stern WTC. Then I drilled a hole into the base of the hull at the stern bracket and threaded it so that I had an easy fixing model for the WTC into the hull. Now all I have to do is unscrew the stern holder, and the entire structure can be slid out. Done.
Once this was in, I could now start to work on fitting the top hatch to the base of the hull. I placed the top hatch in place and then drilled and tapped screws into the bow and stern WTC holder. (Remember the multipurpose holder concept?) This now reveals how well the top fits to the hull. This is a revealing process, doubly so for me as I have done some work on adjusting the lower hull due to my previous cutting error. I won’t dwell on this! I realised as I played with this that the lower hull had too much play. The truth is that PVC pipe is not that rigid. It is very strong, but does bend. What to do?
The only way to fix this was to do it properly. So go back to the lathe and build three new pieces of acrylic (I have lots of this stuff) that fitted the entire inner hell. This is a little like what I did to make the holders. I ended up with three pieces of acrylic (6 mm) which fitted perfectly to the dimensions of the inner hull. I took the wtc out and adjusted them to get them right. The plan is to fix one under the motor room WTC, and two under the larger WTC placed to achieve maximum strength to the hull. Once I had the positions right I then cut them so that all I was left with was a thin bulkhead that fitted under the WTC’s and travelled up the sides of the lower hull. I used fibre glass filler to hold them in, added the WTC’s and let the filler set, then removed the WTC’s and used screws on the top of the lower hull into the top of the bulkheads. Then I added the top hull and adjusted the screws till the lower hull matched nicely, and then removed the upper hull and used filler to fasten the bullheads in place, and ‘threw’ the screws away.
The next problem is that I needed to adjust the positions of the holes that I use for the screws that bold the WTC to the holders lengthwise. (If you remember, these are the bolts and screws that hold it all together and give it strength to managed the internal pressures in the WTC without it popping apart). I needed to adjust them so then were very close to the sides of the WTC to allow space got my new bulkheads. (Nothings is ever easy@)
Now I had a strong lower hull, and I added the upper again and found I needed to do some work to get these to mate nicely. This was now the time to get the filler hot, the sander and to start ‘working’ this hull. Due to my previous build mistake, this resulted in some work, I might say. I used glad wrap under the top hull and added the filler and worked from there. The magic spot, which is when filler is starting to go off and has the consistency of ‘cheese’ as a real help, as I could pull it apart easily and cut the filler with a knife to get it right before it went off.
I like using filler as I have done some panel beating in the past when people still ‘did’ that. It’s messy, but very forgiving and eventually I ended up with a perfectly mating upper and lower hull.
The next step is now to build in the bow thrusters, and then to fit the sail and get the upper servo connected up to it. Unlike other builders I see no problem in mounting a servo in the water, especially if it is doused in plasti dip, and has a small o’ring added to the top servo arm.

Pic are on the blogs

[johnredearth]

Hi all. I have a very unexpected update. I have been working away on the LA and have gotten to the part of finishing the arduino code but have hit some very unexpected problems which have cramped my style.

Because I am writing this newsletter from hospital. In three days I will be under the knife for the removal of a brain tumour. I finally know why it has taken so long to wire up the LA Submarine, which is possibly the best boat I have made. As if anything else matters, I hear you saw? Well life goes on, and I have no interest in stopping.

Today the surgeon gave me news that is as good as can be so far, and as I am a congenital optimist, I believe I will get there. Fabulous friends and family are right with me.
To the LA? I wrote the arduino code and got it working on the bench. I finished the videos about getting the project to that place. Then I started the relatively easy job of wiring all the parts into the WTC. While I did this I managed to blow up my 433 receiver, one of the distance sensors, the txa9548a multiplexer, and possibly the compass. For some in explicably reason the nano arduino is indestructible. Go figure. I didn’t want to blog to you about abject and stupid failure? Always good to admit to problems and mistakes but this was ridiculous!
Writing is not my strong point so please read my blog.

[ccontrol]

John! Thoughts and prayers go out to you and your family. I know you will come through this just fine because you seem the type! Not many would beat their head against some of the projects you have and come out a winner.

Steve

[salmon]

John,
I am sorry to hear his! That is heavy news, but you are warrior. I pray for a complete recovery.
Peace,
Tom

[Oldus Fartus]

Good luck mate!

[sam reichart]

Best wishes for a full recovery!

[johnredearth]

Thank you all so much for your wishes. This has been quite shock!
I will share what happens when you get a brain tumour. This is written before I go off to have my opp and the drugs are kicking in. I can write! Or better you judge on that one!
I work in the human services sector as a consultant. Mainly focussed on mental health. My work ceased unexpectedly 6 weeks again and so I started looking for jobs.
While I am applying for jobs I updated by professional page and contacted people. This took some time because I write well and fast but I use Microsoft spell check lot. The problem is that I write, then correct, but choose the wrong words from spell check. Later I re read the line and even find it hard to see the incorrect spell check correction. I have written the wrong thing. This becomes very tedious. I thought this could be early onset Alzheimer’s. I really did.
Ironically, I applied for a job with Alzheimers Australia!
I worked hard and must have started impressing people. I guy rang and said he wanted to talk with me about other jobs coming up. Great. I also had two other applications that lead to interviews next week.
I had a lunch catch up with some colleagues and when I returned one of the texted me and I could see the text but I couldn’t read it. I went for a panicky walk in the cold air and when I got back I could read the test message. WTF.
So I figured I was just stressed. I am the main breadwinner after all and being out of work is not good. On Tuesday I worked with great difficulty on some material I was writing. I decided to do some exercises on a rowing machine and after I finished I came on hot and sweaty and my capacity to read had disappeared again. I made a time with the doctor for the next day.
I gave the doctor a ‘now holds bards’ version. He said I needed an MRI and I made a time for the next day.
At lunch time the next day I had another interview. It went well but I detoured around issues where I couldn’t think of a word I should have obviously knows. Changed the topic on occasion and spoke at length when a topic flowed. Then I went for the MRI. (got lost on the way) While I sat there Alzheimer’s rang to tell me they had selected me for an interview. I happily agreed but could not remember what the job was and clearly thought I had Alzheimer’s anyway.
On the way home from the MRI, the doctor called. ‘How far away are you?’ That makes the heart jump. He told me this was not good news and gave me the key info about the tumour. I went home and told my wife. Some tears. Then the GP rang and off we went to the hospital. The surgeon gave me some tests and held up a pen and said what is this. I said a knife and he suggested I think again. Described me as confused and distressed. (I read my chart later)
So I cancelled my interviews. I have to chill and wait. International family rallying around and my son has taken control of my life for a while. I am very blessed.
So there will be a little bit of brain surgery tomorrow morning and then a bit of a wait.
Cheers

[sam reichart]

I hope you're doing well post surgery.

[bob the builder]

Best wishes for a full and speedy recovery, John...

[johnredearth]

So now I am back into the submarine. I mounted the hydroplanes onto the sale using the space just above the WTC and below the top deck for a low-profile servo. When I wired it up to the circuit I discovered that it turned in the opposite direction to the one that I wanted but that was simply fixed by reversing the code in the arduino script.

I then built a bow thruster using a piece of PVC and a brushless motor. The details of that bills are all on my website. The result is an extremely powerful Bow thruster which works in accordance with the rudder but only when a particular switch is thrown on the transmitter.

BTW during my experimentation I used a cheap 2.4 gig transmitter and receiver with to avoid any further catastrophic damage to the 433 MHz with unit!

Once this was done I then wired everything up on the bench. This was a very difficult process during which time with I had numerous problems which were eventually resolved when I stopped using the arduino breadboard with and simply wired everything up directly with. The complexity of the system plus the numerous connections with the breadboard just simply threw up too many errors to make this a successful process. As I wired it up stage by stage, testing each stages I went, I ended up with the whole thing working on the bench which was extremely exciting. Nothing was easy!

The next stage was to build the shelving that sits inside the central WTC to enable me to fit the two Lipo batteries underneath. This dictated how much room I had at the top of the WDC to fit all my electronics, of which there are a lot. Of course adding with extra components such as a Bow thruster and a compass into the mix has taken up some extra space and added a lot of complexity for which I make no excuses and if you're following me with this you can leave these components out!

So then I started to wire up of all the electronics into the WTC shelf. That process began by placing the component side-by-side and working out where they would ultimately best fit. It took some time to find the best spot for the receiver and a couple of occasions I wondered how all parts were going to fit. But once the spots were selected I started a logical process of wiring each part up piece by piece.
One part that went in early is by ‘arduino failsafe’. This is a small servo from the RX that sits in the WTC that throws a micro switch at a particular point of travel of one of the knobs on the transmitter. When the switch is thrown, it resets the arduino. This is just fantastic.

I also revisited the pistons as I noticed that the distance sensors seemed to be acting unreliably. I noted that the distance being measured changed marginally if a blanket was thrown over the whole system keeping it in the dark. I put a piece of black plastic on the back of each piston so that the censor had something stable to look at (the back of the piston is white.. this may be a complete furfy) and I ensured that the hole between the bulkhead, the censor, on the back of the piston was completely unobstructed. This has assisted with the stability of the measurements.

With so I began the wiring by connecting the sensors with the TXA multiplexer board (allows you to put multiple sensors into the arduino) and each stage of the build I tested with each component with before moving onto the next stage with. One of the best ways of testing with arduino with is to use the serial monitor on your computer loaded with the arduino software to measure each component and its performance. So gradually with I added the relays which power with the pistons, and for the first time will use the MOSFET to use with the self leveling device be with.

Let me backtrack: As I have been going on I've been adding with ideas to how the sub will work and realised that when I hit the ‘auto’ button with on the transmitter I could make it serve a number of purposes, one of which would be to turn on the auto leveling device. I was previously going to use with a relay to do this however the MOSFET is very simple to add and works flawlessly with the arduino. Using this enabled me to use one extra relay to turn on and off the Bow thruster. The relay with simply turn the power on and off with to the speed controller with that powers the bow thruster.

So I now have all of the components in the boat as I speak. I have a fair amount of work to do to now but it is all working with and I hope on Sunday to have it ready to begin the manual process of adding led to the Hull to get it to sit properly in the water at neutral buoyancy. With I might add that my process forgetting a submarine ready starts with neutral buoyancy not surface buoyancy. This is just my preference and it is no better or worse than other methods but I like to get it right first and then get it sitting nicely on the surface afterwards is going to be fun.
Busy busy

Full blog and pics here
John

[johnredearth]

Due to significant personal changes I have decided to change how scratchbuildwithJohn works. I am now in the early throws of battling cancer. Not fun.

Previously, access to all the videos was only possible through membership and many of the videos on U-Tube were restricted.

From now on, all restrictions will be off. All my videos will now be accessible on U-tube, however the website is still the best place to go as the diagrams, codes, and plans will be there. Plus it is easier and more intuitive to navigate.
So, that’s the downer stuff. Let’s get to the LA.

This Sunday I will take the boat to the local club house and drop it into the water for the first time. This will not be to sail it per se, just to ballast it. If all goes will we will have a sail around on the surface.
This week I have been fixing apparent bugs. All these little issues will be addressed in the ‘want worked and what didn’t’ at the beginning of the video series but I am still in testing mode right now. More bugs will spring up.

The first is the laser sensors. If you remember I had some inaccuracies in their use, in that after I turned them on there appeared to be variation for 5 minutes. Not good. Also I noticed differences when the lasers were in the dark or light. Of course they will be in total darkness in the sub, apart from LED’s blinking etc. So I addressed the adafruit team and they sent the following diagram and suggested I reduce the distance between the sensor and the piston. So I have done that significantly and it works far better. My initial testing that led me to setting them back was clearly flawed.

Secondly I re build and designed the output of the main motor utilising the fantastic capacity of the brushless motor to be replaced with an extended version, completely removing the necessity for a second connector, which was producing vibration.
Then I started adding ‘in wall foam’ to the sub hull, limiting it with, yes, glad wrap, and aluminium flashing. Once it had dried it looked hideous but a few slices with my knife fixed it. I added more where necessary and then ensured that there were drainage holes. Then I sealed the ‘holes’ with good old fashioned ‘no-more gaps.’ (I know no-more gaps will not seal, but it will fill holes). Once that was dry I used plasti dip to pain the foam plugs. That does seal.

I may add that I had a comment from a subscriber that if the foam is not properly ‘set’ it can expand again if exposed to heat such as sunlight, thus blowing up the boat. It was quite a scary story so I levt the hull in the sunlight for a day to make sure it was set. It was and did not expand any further. I will do that from now on!

Then I started to do a better job of sealing the servo that sits in the water. (Under the conning tower). I think the method is about as good as it gets. I used dual mix silicone to fill the electronic part of the lower half of the servo. I then drill a very small hole into the top, and using a syringe to add baby oil. Filled it to the top. I am using see through servo’s so I can ensure they are full. I sealed the tiny hole and it works.

So on Sunday I will set the pistons to where I think neutral buoyancy should be, and drop it into the water. I am hoping it will float nicely. Then I will add led to get it to the magic state, and take the boat out and add the led. Retest it and take it out.
Then I will set the pistons to full buoyancy. I will take the WTC apart to do this as I don’t want pressure issues. Then I will drip it in again and adjust the pistons to get the boat to it’s best position.

Out it will come, and I will take it apart and connect the arduino to lock in the positioning of the full flotation settings.

Then comes the big test. I will open the boat up, drop it in the water and withdraw the pistons. Pressure will build up and I will test for leaks.

If there are no leaks, I will take it for a run.

For the whole blog with pics..

Big day

[johnredearth]

First and second trim sail

If you have been following me, you will be aware that this boat is different. It has twin pistons that are controlled by an arduino which is in turn provided info from two laser sensors that measure the position of the pistons. The readings from the sensors effectively limit the travel of the pistons to a maximum point (fully surfaced) to a minimum point (sitting on the bottom) to a sweet spot (neutral buoyancy). This latter can be changed from the RC, but the other settings need to be changed in the code.
Prior to the water test I set the maximum and minimum points in accordance with how much room the pistons had to travel. With the WTC separated to nullify internal pressure, I put the pistons in the middle of their proposed travel, and then connected every thing up and pulled the pistons in. They were labouring heavily at fully dived, and labouring at maximum buoyancy. This was not good.

So I made an arbitrary ‘sweet spot’ and set the pistons that that position and turned the power off. I took it to the water and dropped it in and it was amazing at how buoyant it was. This was good as I could add the lead to it and get it to neutral buoyancy , and the added lead would add to stability. I added lead in strips to the outer hull until it was almost there, and took the boat out and beat the lead into small shapes and fitted it into the hull. They repeated the process and got it to neutral buoyancy and it was stable. This was very good for the first try.

I then took the boat out and disconnected tho WTC (to nullify the pressure, particularly when I had not done a pressure test) and set the pistons out to max buoyancy position. I dripped it in the water with the power on, and it sat far too high. I had to withdraw the pistons using the RC to get the boat down to sit at its proper level. (Marked on the hull)

Out of the water again and strip down. To my amazement I only needed half the amount of ballast as I had provided in the ballast tanks. Also the bow ballast did not need as much as the stern, even though I had designed them for the opposite. This also bodes very well for handling the pressure!!

So out again and I connected up the computer and adjusted the arduino settings for the new reduced pistons stops, which are now tuned to the lead ballast and the dictates of this particular hull.
I then dropped it in at fully buoyant and gave it a run. The bow thrusters did not work but I found the rudder was not entirely useless. Often with speed the prop twisted the hull a bit, but that quickly became an issue of how well I sailed it, and the boat looked beautiful. I will tweak the prop for more thrust at home, but in general it was a very successful first trip.

So home for some work. The bow thrusters had a mechanical issue which I fixed. (Often scratch built items need a bit of ‘tweaking.’) I changed the ‘piston stops’ to sit in the middle of the piston travel, tweaked the prop to increase it’s ‘bite’ and added catches so that I could better secure the lead for starboard/port adjustment.

Back to the pond. This time I reset the lead using the initial process of estimating neutral buoyancy, and resetting the lead, then set off for its second run. The bow thruster is a killer. Really whips the boat around. I also tested the compass and yes it holds a course if needed. Then I submerged the boat using RC and reset the neutral setting. Once it was happily ‘hanging’ in the water I set the boat to automatic and sailed for the first time at neutral buoyancy. Completely successful noting that the NP setting also turns on the self levelling device and the sail hydro which holds the depth.

After a short time I unset the auto and clicked surface and up it came. Then I took it out for a leak check. Not a drop. I must note there that when I came to disassemble the boat, after I took off the bolts that hold it together, I had trouble separating the WTC apart. I thought it was a couple of connectors that may be binding, but realised that the pistons were set to surface mode and that there was negative pressure in the hull. Closing the pistons popped the WTC apart. Have to remember that one. I put it back in and dodging yachts that seemed to believed they owned every inch of the lack, came it several submerged runs.

It is interesting that it is such a different boat to sail as it has little buoyancy and the controls must be used with great sensitivity. It is easy to heal it over, or to over-power it. Also I had not recalibrated my RC. IE the arm that controls the hydro is fixed (ie it stays in position when moved) and the throttle is set to spring back to neutral once let go. I had to pull my RC apart and change the mechanical controls to make it do the opposite. Also the prop really kicks it over to port or startboard unless used with sensitivity so the above is a necessity.

There was no water anywhere in the boat but the bow thruster leaked. Adjustment two required.

Bloody beautiful.

blog with pics here

[johnredearth]

Dear all

I have skipped a couple of states here but I have some very nice pics of the progress of the project here, and all the other bogs. As you will note at the end, blogs are not my strong point right now.

This has still been a full on week and I am immersed (no pun) in the build of the LA submarine. As you can see the plates are going onto the Hull and it makes a dramatic difference. This is really tedious work has not only do I have two cut each plate individually I then have to glue it on with Apoxy. What I know however is that it's going to look extraordinary. Looking at the pictures of the Los Angeles it's clear to see that most of them have these sound deadening plates. Once I finished glueing them on I'm going to spray the whole boat with a layer of grey etch. All of that work is suddenly going to become much less obvious but that's where the magic comes in. In real life it's not that obvious!

Once I've done that I'm going to mark the halfway mark around the Hull and then paint the section red. It's important to remember that if your Hull is going to be red and black you paint to read first. The reason for that is that you can butt black not red but she can't do it in reverse without the black bleeding through. It is just an issue about making sure you put the colours on in the right order first.

Once that's done am going to do some touching up with some light grey on the sale and around the hatch is. Then comes the fun part where I make the white deck owls on the computer. Guess what is really fun about this stage is that every step transforms the boat yet again.

I have new videos on the site concerning wiring and circuit diagrams. See it under LA 14.

Anyway I also have another task ahead. Many of you will have seen my Corvette in operation. It features on my you Tube page and I have some great video of it surging toward what looks like my U-boat as seen from the periscope.
Anyway that boat is built using simple techniques. It has within the Hull bank of NiCad batteries. I use NiCad batteries because I can charge them in the Hull. Clearly a pre-requisite of using Lipo batteries is that they need to be removable for charging otherwise you could have a disaster on your hands. So I started playing with that idea and in the process one of my controller servos died.

As per the picture you can see that I have a bank of servos on the starboard side which control microswitches which in turn powers the motor that turns the turret, and the motor that squirts the water. It works sublimely well as it is. Anyway one of my services died.

So rather than by another servo I have decided to implant and Arduino into the boat which I will program to fire up relays. Secondly, while I am at it, I will add a compass is a little boat. Because I'm going to save so much space it will then enable me to slip the Lipo in an out of the boat. I will need to also wire up a voltage regulator to make sure that I don't blow up my bow turret water pump!

So this will be an interesting project to remove some traditional methods of controlling the boat and replacing them with an Arduino, and a couple of relays. I've already written the code for the Arduino and I will video the process and put the code and the circuit diagrams on the website. Start that process will before I have finished the LA.

To finish those of you who have expressed your best wishes toward me considering my current physical battle I would like to say that I have started a blog about it all that it is invite only. If you would like to have some information about what's been happening with me semi-request and I'll send you the link. All of safer now is that I'm feeling very well, and in fact said to my doctor that I feel like I'm in the phoney war stage. The doctor looked at me and said there's nothing phoney about this!

If you find some odd words in this I have to admit to it being part of my problem. Spelling is a nightmare and I am using dragon dictate, which in turn doesn't always print what I say!!

John