Robbe Type XXI Modified to Static Dive

[Guest]

I have started building this model and will be modifying it to dive staticly.
I will have to install larger batteries two 12 volt 4 amps that fit inbetween the rails just fine.
The main frame had to be cut into two segments and the ballast tank glued in place while in the wtc to keep it true.
The picture shows a glueless baffle tank that I wish I had developed years ago its so easy.
The hull has allredy been built and that alone was alot of fun since there are several frame parts and grills to install.A super strong single bolt WTC is also provided and is about 3 inches in diamiter and a yard long at least.A single large O ring makes the seal at the stern cap and another for the allen head 4 mm bolt.Nice east acsses to the inners.
Another interesting thing I do is not to glue in the WTC,that way lead or foam can be installed as nedded for ballanceing without a hassle of boing thruogh the deck ares.
This model is awsome,tons of parts and super detail on the deck as well as the hull,all the limberholes are CNC and as are the rest of the frame parts.Very nice mast and snorckle.Comes even with motors props,shafts a huge bag of parts!Great high qualty kit with retractable diveplanes and 73 inches long!

Ill be installing a pump system similar to the one used in my U-32 except the pump will be in the freeflood area in the stern and other pumps for the masts and diveplanes in the bow using syringes as rams.

Ill post more later.
Dave Amur Ship Yard

[greenman407]

Ah Dave! I see you

Ah Dave! I see you took me up on doing a builders thread on one of your boats. Cool!!! Itll be nice to see what goes on inside. You just sold a type 21 on Ebay. I guess you did it because it wasnt big enough.

[Guest]

Hello Mark
Ya I am going

Hello Mark
Ya I am going to try to get a thread on this sub ,it should be interesting since again I am going off the manuals build.

Also the Type XXI I had before was much smaller and had much less detail and I love the biiger subs.
This one is also cheaper!

Dave Amur Ship Yard

[Guest]

In these pictures the stern

In these pictures the stern shafts and boxes are glued in for alighnment and to be sure that they turn freely.
Note the red pump ,this one is for the dive system and is in the freeflood area .A filter will be atached to keep the pump ect clear.
The WTC was moved back as far as posible so that the ballast tank is as centered as posible,about 2 inches,no other major mods in this step.

The wires exiting the WTC are for the 3 pumps,ballast,masts and dive planenes.Also running lights and other functions.

A military multypin connector will be installed on the uper aft rib support for easy disconnect.
Still not installed are the water cooling coiles 2 each,2 seperate systems are shaft driven by the gears seen on the shafts in grey,from Legos.

When completed the pumps will sirculate water and antyfreez around the coiles of the motors.Cool motors means longer life and longer run times and heat expantion is minmalized.

I had to make my own stuffing boxes since the gear had to be installed and the shafts shortenened to take up the WTC moved back.

Master Air screw 3.0 gearboxes that have ball bearings will be installed instaed of the suplied larger 6 volt motors that are dirrect drive.Very necessary to give longer run times.

2 ESC from Aquacraft that I have discovered work very well for subs and will be used on all of my upcoming subs.
Concurrently completing the Engel Typhoon keeps me busy!
Dave Amur Ship Yard



The Amur Ship Yard parts storage and research warehouse,very heavy box!

The Alfa 705 and U-32 in sorage area awaiting sailing orders.

[Guest]

Here is the modified "core"

Here is the modified "core" of the WTC ,it was biult as per instructions then cut to fit the ballast tank and batteries.
Set inside the WTC it hardened with GOOP to be very strong and will not crack when installed.
Im using all micro servos and switches,these Tower pro servos are very cheap and high torgue!They have dual ball bearrings and coreless motors.
This way more space is available for other systems.
Main off/on switch is underneath and close to the rear bulk head.
The only thing I did not like about this kit was the rear bulk head,its made from thin PVC then glued into a stronger ring,so what I did was to epoxy the intire pvc and ring together but with an extra thick amount of epoxy so that the wall is reinforced to at least 3 times the original thickness.
Next the 2 speed controllers will be instaled underneathe the servos chelf and then the forward battery .
The small solinoid is for the WTC vent.

Dave Amur Ship Yard

[Guest]

Here are the mechanical masts

Here are the mechanical masts platform that will be installed under the sail.
The legos system works very smothly and is easy to service and will be accesable from the top by removing the deck.
Only the platforms and axle bearings are fixed the rest can come out.

Later I will make the 2 AA guns move as well ,probably hydraulicly in combination with Legos.

The mast system uses a 90 degre gearbox that is driven by another gearbox that is geared down to get the desired speed of movement and torque.
A blue speed controller is used to reverse the servo and provide the desired speed,very simple system and cheap to make.
The lead screw for the masts is made from legos and 2 3/16 in stainless precition ground shafts that just so happen to fit perfectly in the Legos shaft sockets making it easy to alighne the 2 shfts and the stainless threded rod also screws rihgt into the reciever socket of the Lego gear box without destorting the socket.No modification or even glue is needed for the lead screw ,just at the platform 2 brass screws are glued in place and set to dry,the hardest part is this step but once it runs smothly let it alone and it will set perfectly ,usualy I use CA fast set to get the preliminary setting of the 2 bushings then once satisfied I glue the assembly with GOOP very carfully!.
Once finished it runs so smoth up and down .
The reason I did it this way and not hydraulicly was the lack of space downwards into the hull since the WTC is present.
Always bench test therouly all components then install and think well ahead as to future foam/lead placements and other mechanisms so that there are no clashes!

Dave Amur Ship Yard More great pics very soon

[Guest]

Also as seen in the

Also as seen in the pictures the white gears are clutches that are installed to prevent damage to the geartrain excetra.No limiting switches needed just visual operation.
Also the 3 shafts off the gear drive 2 will be cut off but are used in determaning the drive speed.

More to come

[Guest]

I have been busy today

I have been busy today with the instalation of the mast retract system.
Also in the pics you can see the bow plane retract hydraulic system .
A single large syringe moves about an inch and a half very slowly to operate the planes,glued together onto the plunger the rods connect to the cylinder.

Also the rear gearbox is screwed in place inbetween the the last 2 ribs and can be removed by removing the aft section and then the pressure hull pulled out.
In this sub as in the U-32 the entire WTC can be removed to fasilitate the delicate operations of ballanceing the sub and is not mentioned in the manual but it sure does make it so much easier to acomplish.

The U joints and shafts are all Legos and can be removed and atached.

[Guest]

the sail
http://www.postimage.org/gx1R9HM9.jpg

Till Manana

Amur Ship

the sail


Till Manana

Amur Ship Yard

[scott t]

Lego my submarine. http://www.subcommittee.com/forum/icon_confused.gif
Those

Lego my submarine.
Those are some pretty slick mechanical
devices.

-Scott

[Guest]

Yes they are ,there amazing

Yes they are ,there amazing and your imagination and mechanical skills will be fullfilled.
Try some at bricklink.com

I am now installing the rotating turrets mechanism.

It is importatant to use only Lego components,there is another make that look the same and even interlock with Legos but the plastic is not the same,it has a much lower melting point and might warp in the sun.
Legos dont and are made of a high impact and thermal plastic in very high precition locking components and come from Erope.
These are some of the Lego/Technicks components I have used with great success,they are gear boxes and rams ,I dont use the rams yet,I like syringes better more stroke and capacity.The boxes can be conected with shafts that can be cut to lenght and have U joints and bearring blocks that will amaze you with there smothness.
Dave Amur Ship Yard

[Guest]

Here are some more advancements

Here are some more advancements that I have maid to the XXI.
First the main shaft cooling system for the motors,note the 2 indidendent systems since there are 2 seperste ESCs and if one is in reverse well you know what would happen to the drive.

The 2 small coils are the heatexchangers,this is a sealed system with a few drops of antifreez to lube the pumps.
Air craft 3/16th aluminum tubbing is used for its lightness and ease of bending and it fits the large fueline tubbing perfectly.

The pumps are driven by the Lego drive shafts and U joints and bearring blocks all lubricated by water.
I have used this type of setup in other subs and have not had to replace a sigle Lego component due to wear!Good stuff and very cheap.

Also I would like to say that this sub was the most easest to ballance I have ever done.It took 2 hours to obtain a level serfaced and level submerged nuetral bouyant state and serfaces level.!
With just one bar of supplied lead of which there was 4 the keel waight was laid and then some foam,by the way I use marine grade foam from of all sources ,body boards I buy at garage sails for usualy 3 to 5 bucks!
That stuff is supper strong durrable and easy to cut and totaly closed celled.

In the picture you can see the method for ballanceing with rubber bands.There are 2 longer foams inside just aft of the forward dive planes.
Also in the pics is the hydraulic retracting dive plnes,wait till you see how smoth and realisticly they operate.The pump is in the acsses area in the bow on the keel.The syrige is for the counter volume of water and is set to lock when the planesare retracted while the ram at the top that operates the planes also locks at the bottom when fully deployed,no switches no electronics except for the blue ESC used to reduce and switch the current for the pump at full 12 volts the pump moves the planes too fast. Simple system and so sweet to watch operate right down to the sound.The green fluid is the antifreez and water.
I must say that this sub dives like an elivator and serfaces nice and slow very scale like on the new pump system I have developed and am very happy with its performance.

Later Ill show the guts a real eyefull.
Also the masts go up and down now and the turrets I am happy to say rotate in both directions in variable speeds,there geared together with a Legos gearboxes U joints and drive shafts and feature a break away joint.

The drive for the guns are located in the secound WTC maid from a Foccus free camara case,high qualty case that has alot of things we can use ,like knobs and switches that are all made waterproof ,see thrugh and cost get this 9.95$!

I just installed the diveplane servo and gun drive servo,the later is a microservo that I hacked or modified so that it can rotate 360 degrees on comand.Just remove the gear stop on the large gear and glue the potentiometer so that it does not rotate in the center position.
A radio controlled mini graer motor is obtained in this way,then connected to the Legos frive train and your OFF.

The entire sub uses the same highpowered micro servo from TOWERPRO and so far are very strong stable and inexpensive.Get them in bulk off Ebay directly from China.
What is next are the wireing of the connector that will be installed inbetween the pumps,a military cannon plug will be used a 14 gold pin type.
Enjoy the pics and any questions just ask.

Dave Amur Ship Yard

[Guest]

Another note; the syrige in

Another note; the syrige in the bow is verticle why?

To keep out dirt that could jam or damage the plunger seal.

[Guest]

I am happy to anounce

I am happy to anounce the first sea trials of my Type XXI took place Yesterday at the local pond and what a great run ! Nothing went wrong and the sub with just a priliminary ballanceing was right on the water line was level and upwright.
I then made bells for ahead slow then half and eventualy full thrughtle!

She can realy move without any adverse imballances since she slices thrugh the water so well this model is so sleek compared to the U-32 or Russian nukes.
Very eficient lines indeed.I could not get to the low battery charge after an hour of running at 3/4 speed.

I then ordered a dive at slow,deployed the diveplanes and set for dive condition.
Slowly and very scale like she cleared the deck awash and went to periscope depth,totaly under control with plenty of margine to maintain depth ,it was a total surprise to see this unfinished beuty perform so well and was mesmerizing to watch how smoth she ran.

Then it was getting dark and I serfaced ,pumped out the water and up she came with no adverse conditions no bopping or porpposeing ,I dont think it will even need a leveler it is that well dialed in !
I then wanted to see the turning radiuse as this sub is notorios for not turning sharply,well I was surprised to see her turn very well on the serface but even better underwater.
By reversing one prop and forward the other she turns at full emergency turn.
For normal running I programed the radio to do smething rather cool,when unerway no mater the thraughtle settings 2 each the corresponding prop will go faster forward help turn the sub ,like what we do manualy its just done automaticly,nice feture and saves on the fingers!And can be totaly adjusted when to engage and how much individualy.
Also the turrets rotate bidirectionaly and varible speed as did the real ones , but do not elivate.I will post vedeos today and explain the workings.

Upon reviewing the the sub at home there was a small leak and found it to be a check valve at the bottom of the WTC,the one that retrieves the water from the WTC if needed.It turned out to be not sensative enough and I changed it for one that was more sensative and it worked just fine.

Whats nice about this ballast system is that it can be diagnosed with great ease,just run a supply of water to the open WTC and pump then activate the pump and watch for leaks,no dangers or expence or wonderring if there is enough gas.

I gues one could add food dye to locate a stubborne leak.

Well thats about all for now and stay alert for the vedoes to come!

Dave Amur Ship Yard

[g2tiger]

Good work Dave!

Dave,

As usual you are a blue chip sub builder. I was wondering how you determine what to look up when at the brick link site? How and what do I search for?

Charlie