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[timgarrod]

glad to hear everything went well. now its time to put you feet up and recover and look forward to next year flying and sailing that Sub .

[U-33]

Welcome back, JR...glad all went ok for you. Now just take things easy for a bit, leave the sub alone, and get yourself healthy again.

See you soon,

Rich

[Davy1]

Very good news, John.

Get well soon.


David

[Martin (Admin)]

Very good news, John.
Get well soon.

..... my grass needs cutting if you want some exercise!

 Martin 

[salmon]

Yes, good news indeed! I agree with the rest of these men, get rest, heal, then back to the sub. The sub can wait.

[sub john]

HI Subculture
            Yes you are right Andy it is a major op i must say that i am getting more pain from the cut down my leg than i am my chest. The pain from the chest is bad enough at the moment i feel as if i have gone through a mangle but enough said about that. I have got loads of things i won't to do but they will just have to wait a few weeks until i start to feel a lot better.
 
Andy i won't to get back on to doing piston tank i have a few new ideas on how to get full linear feed back all the way down the tank secret is i might be able to do it with magnets so if you are still interested in having a go at making a piston tank let me know,reason why i did not won't you to start making piston tank didn't know how things was going to turn out with heart bypass but as you know all the soft ware and drive circuit H bridge and circuit board is all done now and  what would be micro switches on the end of the tank can be done with hall effect senors
 
  Thanks for get well wishes Martin will have to pass on cutting the grass i am struggling to walk down a garden at the moment never mind cut it.
   
   Would like to thank every one for the get well wishes
                All the best Sub John

[Subculture]

No problem. What sort of size piston tank would be optimal? I can machine almost any diameter, but one around 45-50mm diameter would be easiest as I have the right tubing for that to hand. Length wise, the tubing I have goes up to about 25cm or thereabouts.

[sub john]

HI Subculture
      First question is can you make the piston travel up and down the threaded rod with gland or would you won't to make it so it work's the same as the Engal tanks so the threaded rod travels out the end of the gear box. Other question is with the idea i have got with the linear feed back pot the company that i have found can make these up to 2metes long and are true slide controls and can be bonded down to a surface so these would be ideal for a piston tank wafer thin as well. Only problem is can the piston be made not to turn inside the tube as the piston needs to have a magnet on it and the magnetic flux will go through  the wall of the tube to where on the out side will be the feed back pot which will have a magnet on that, so the magnets have got to stay lined up have a think and see what you think thanks for the offer of doing the piston tank. Other question how much do you think it will cost to make it if you can do a tank that is 50mm diameter inside and all so 25cms which filled would give 502 grams weight of water, but if could be made longer it would be better just let me know
       All the best John

[Subculture]

Making the piston run up and down the thread shouldn't be much of a problem; that's how Ron Perrott's tanks work, and they're well proven. Just means putting a stuffing box on the piston to seal the thread.

Keeping the piston from turning/revolving, is a little more tricky. I've seen air motors that use octagonal cylinders and pistons, but that's a bit beyond my machining skills.

The only practical way that springs to mind is to put an additional rod above the main thread, and that would also need sealing against water ingress if that rod also remained fixed. An o-ring in the piston should take care of that, but it's another point of potential failure.

Regarding size. I can do 50mm up to 20cm long, as that is the longest piece of pipe I have in that diameter. I got this sent over from a fellow modeller in Germany, and he cut it into sections to keep postage sensible. I've had no luck finding a supplier here in the UK for 50mm I/D pipe. I do have some 60mm tubing with a 55mm internal diameter, and I could make that long enough for a 500cc tank. The latter pipe is used for coaxial flues on condensing boilers, and the internal finish is totally smooth and accurate, unlike most extruded plastic pipe.

The other alternative is to go to 80mm. This involves laminating the tube on a former. I've had a go at this in the past, and it worked okay, but I used polyester resin, and the tube moved a bit. I could have a crack with epoxy resin and carbon fibre which should should produce a light but strong tube that stays true, and you would only need a tank length of 10cm plus piston and bulkhead depth for a volume of 500cc. I'm still experimenting with this at the moment, so might be better to go with the pre-moulded pipe.

[sub john]

HI Subculture
       Fine on making piston tank work the same way as Ron Perrott's, I know that stuffing boxes can be a bit of a problem traveling up and down the threaded rod. You had the same idea as me have a additional rod above the threaded rod to stop the piston rotating where the rod goes thought the piston it will need a brass bushing both sides of the piston where the rod goes through may be with the silicone O ring sandwiched between. When the piston is locked in to place by the rod stopping it rotating you can place a magnet both sides of the piston these then will switch off the hall effect sensors on the out side of the end caps on the piston tank. Another magnet will be placed on the out side edge of the piston and if the piston wall is say made of plastic it will pass through the magnetic flux to a magnet on the other side which will be linked to the feed back pot i know i have said this bit before.
     
        You said you had got some 60mm with a 55mm internal diameter and could be made to make a 500cc tank you said the pipe is used for coaxial flues on condensing boilers the question is would it pass through the magnetic flux from the magnet on the piston to the out side wall to connect to feed back pot is the tube made of stainless or aluminum, i think it will make a interesting project.
       
        Andy some body has just given my one of those Neptune's submersible its not my type of submarine but i will have a go at refitting it as the guy took all the insides out so all i have got is the hull but what i did think about was it would make a ideal building platform to put the sonar control system that i won't to do as it is small, when it is all fitted in will be able to take it to a swimming pool  or some other clear water and test it out with out having to take a 12FT sub out. Just to much agro just to test new ideas plus every time you do put more things in you have to re trim the sub which is a real pain in the back end. Hope to take the sub to a lot more shows next year just got to heal a bit.
     Thanks for your help Andy All the best John

[Subculture]

The pipe is PVC so no worries there. Condensing boilers can have plastic flues, as the exhaust is cold enough not to soften the plastic.

Does a Neptune need a 500ml tank? I thought they had a bag that displaced about half that figure.

[essex2visuvesi]

The neptune bag is much less than 500ml... more like 200ml if that
I had one to use in my seawolf conversion.
Can't remember who i gave it to now, someone on here anyway.... might have been Rich (U33)

[Subculture]

Just had a look at the manual for the boat, says 7.7kg displacement surfaced and 7.95kg dived, so yep 250ml. So either John is pitching for a higher waterline or he's doing a special.

Poked a few numbers through my excel spreadsheet, and it's given me in the ballpark of a 20 watt motor to run a 500ml tank with a 55mm piston up in about 17 seconds. The motor will need to be geared to run around 750 RPM if using an M6 thread to run up in that time. All the geared motors I have are a little slow for that, or too puny.

Something like this would do it-

http://www.ebay.co.uk/itm/800RPM-12VDC-2P-4mm-Shaft-Diameter-Electric-Geared-Box-Motor-/290957103353?pt=UK_BOI_Electrical_Components_Supplies_ET&hash=item43be6510f9

[sub john]

HI Subculture
     The piston tank is not to fit the Neptune, i am going to put a bag in it the same as the original sub like you said it's only about 250ml of water it takes on board to get it to dive will have a look to see what motor and gear box i have laying around if not will have to see what i can get hold of. You said about 750rpm a minute
      All the best John

[Subculture]

I need to be around that rate for the tank to fill in that time window. All the motor gearbox combos I have are about half that or less, and they would do the job, but you'd be looking at a dive time of at least 40 seconds, which is ponderous to say the least. I have one or two bits and bobs I could probably adapt, but when you can get good units for a few quid on ebay, it hardly seems worth mucking about.

With the spindle fixed, the motor can connect to the spindle directly via inline gearbox, which simplifies motor installation as you don't need any drop gears.

[sub john]

HI Subculture
       Not felt to good the last two days so sorry for replying a bit late, if you can get a gear box Andy just get one and i will give you the money for it. I have had a look and can not find a gear box  that would do the job, all the stuff i have is just to big like you said it dose not seem worth mucking about when you can get a gear box for a few quid.
         Thanks for your help All the best John

[Subculture]

Okay, no probs.

[Subculture]

Been having a rummage around. Found some geared Maxon motors. These are 24 volt, which is probably a bit high voltage for what you want, and they're too slow anyway. However they have very nice 18:1 gearboxes. One of the motors is kaput, so I can very likely fit another motor. I have a good selection, a 280 motor would work well, but I'm thinking that you may be more likely to use a 12 volt system, and my 280's are 6-8 volt motors. I do have some 12 volt motors of modest size that may do the job.

So what voltage do you think would be preferable?

[sub john]

HI Subculture
      Maxon motors that are on 24 volts would be to high voltage was going to use 12 volts to run piston tank on, but if you can use a 8 volt motor i should be able to get it to work OK but i would sooner stick to 12 volt system if possible. I have sent you a PM which hopefully you have got thanks again for having a go at piston tank it,s nice of you to do it
      All the best Sub John

[Subculture]

Okay. I have quite a few 12 volt motors of various vintage, so I'll see what if I can adapt something. Shaft sizes are usually the bug bear, European manufacturers use metric shafts and Japanese often go with imperial!

[sub john]

HI Guys
       sorry to say not been very active the last few months, with triple heart bypass then left lung cavity filled with 4.5 liters of fluid ended up back in hospital but seem to be getting over it now. The good news is the misses has took pity on me and just brought me one of Alexander Engel GATO TMAX with all tanks and add ons to go with it, got email today to say it had been shipped out to the UK, what a nice Christmas present it is will have to start building when i get my hands on it, have loads of ideas what i wan't to put in it.
       
        So with a bit of look will have some thing i can take to shows  and it will  works just as good as my big beast does with a bit of look, but if i do a build log will have to start a new thread
                          All the best Sub John
                    PS WISH YOU ALL A MERRY CHRISTMAS AND A HAPPY NEW YEAR

[U-33]

Good news that you're getting better now, JR...nice to hear from you again.


Can I borrow Pauline for a while....I'll take an Engel Nautilus, please   


Merry Xmas to you and and yours, John...


Rich

[sub john]

HI Richard
       Sorry to say I'm not letting you have Pauline for a while she has got my spraying to do, and she said I'm not a money tree get your own Nautilus. I'm sitting hear now waiting for the sub from Engel to get hear i think the first thing i will look at is the tanks and the way it all works i will keep you informed. One of the things I'm not keen on is people use a channel on the transmitter for the front hydroplanes to make the mechanism fold them up and down in to the deck i think that will need to be reworked so it will do it all its self  when it dives its to easy to forget to flick the switch on the transmitter when diving and the front hydroplanes don't work because they have not folded down. Just my thoughts i know a lot of people like to keep it simple but not me.
         
       Have a nice Christmas John

[sub john]

HI All
      Hope you got the presants that you wonted for Christmas.
  I have started to build the Engel Gato that i got for Christmas but was not happy about just having one center hatch for excess to the inside of the water tight compartment so i have made a hatch at the front of the sub and the back, as there is going to be a lot of electronics in side so will need easy excess. The Tmax control board for the tanks that came with the kit  i have decided to scrap that as it will not do what i won't it to do, and i do not like the idea of relays for switching ballast tanks so it has had to go. A little while ago i designed a proportional  piston tank control board which will take the place of the Tmax diving system there will be one board for each piston tank i have been trying these boards out on the two Engel tanks and what i have done is put a tank on each end of a seesaw the sort of things you see in a kids play ground, so what happens is when you fill the front tank on one end of the seesaw it starts to tilt downwards the last 20% of the tank goes in to proportional mode the piston tank on the other end of the seesaw races to catch up and this tank is connected to a very sensitive leveler which is in the middle of the seesaw and as this tank comes to the last 20% of the fill of the tank it goes in to proportional mode and what happens is the seesaw stays perfectly horizontal. If you place 5 grams of weight at one end of the seesaw the back piston tank ratchets in to keep the hole system level i hope you guys can see where this is going. So the next step is to have the front tank connected to a selectable depth control so what you should be able to do at the end of the day is put the sub down at say 2ft in depth in the water sitting still and it will just hoover there with a bit of look hope you have found this interesting as in time this system will be going in to my big sub.
                                                                          All the best Sub John

[sub john]

HI Guys
     I was hoping to come to model boat mayhem at Wicksteed park  and bring the sub but the consultant at the hospital said it was to early to move some thing as heavy as that plus the misses said no so i ended up grounded but now i have been given the all clear from the consultant i hope to be there next year.I must say sorry to Martin admin as i told him that i would try to bring it but it was not to be.


     I must say that i had a big problem with the transmitter for the sub a few weeks ago, i had external battery plugged in to the transmitter it was turned off at the time so the external battery should have been disconnected and had a charger plugged in charging internal battery and seemed to be charging OK and at the time i was on the phone talking to a friend when there was 2 big bangs and smoke pouring out of the joy sticks on the front of the transmitter even when i pulled all plugs from the side of the transmitter smoke was still coming out what a mess it made in side, and all because of a relay sticking. The problem is this transmitter was made 25 years ago and would be very hard to build a new one to match it to the sub so i had to try and repair it as you could not buy a transmitter with as many channels as that has got so if i did not repair it the sub would have been scrap. Took me a week to repair and it turned out to be a pain in the neck but all done now and seems to work fine thank goodness.


     Have been hard at it building Engel Gato and have done lots of modes to it, been designing a-lot of electronics to go in side. I have not done a build log on it as there seems to be a lot of people that have done build logs on the Engel Gato already, so it did not seem worth the time doing another.
                    All the best Sub John