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[carlmt]

As well as the resin cast fittings that will be supplied with the kit, the modeller would also be able to purchase separately (from the Shapeways site) a full 3D printout of the observation lounge seats and a full 3D printed model of the bridge interior.  These will be offered as optional as they are quite expensive and, if included in the kit, would push the kit price up.  Not all modellers would want to avail themselves of the 3D models and would be quite happy to detail these elements themselves, so should not be penalised on kit price unneccessarily.
 
The observation lounge on the real ship:
 

 
And the 3D printed model:
 

 
The bridge of the real ship:
 

 
And the 3D printed model:
 

 

[cos918]

Carl that is a real cool touch . I real like the idea of upgrade options . Can not wait till you start the ferry i want


john

[carlmt]

Not too long now John......working on the drawings in between times at the moment 

[carlmt]

I really wonder sometimes if I am not being a tad too fussy about the 'bits' for this boat 

This is the rudder skeg.  It has taken me all evening - some 4 hours so far - to get this far!! Made a few mistakes....the first was forming it out of a lamination of 6mm ply instead of solid wood.  The damn ply laminations were weaker than my glued joints and both the corners sheared off.  Then the 'tongue' on the skeg disintegrated when I bored the rudder shaft hole through it (ply laminations again) so had to replace THAT with a solid.  Then I find that the whole unit isnt quite deep enough, so now laminated a 0.5mm piece of styrene to the bottom.  Have to let that dry overnight..................

This is supposed to be the master that will be moulded in resin:
 

 
which is supposed to be mounted here:
 

 
it will need fairing in with some filler, and I think I will suggest in the kit instructions that it is very lightly tacked in position and secured with a self-tapping screw from inside the hull - just in case the rudder needs to be removed.

Ho hum.........nowt I can do with it tonight, so it is back to filing the window openings to shape and size.

Did I tell you I had a few of them to do???? 

[carlmt]

That very kind gentleman, Mr Milbourn, has very graciously designed the electrical power installation for the Free Enterprise (thank you kind Sir!), with a set-up that will allow mixing of the rudder and the outer motors.  The option of a bow thruster is also included.
 

 
We have still to get our heads around the workings of a bow rudder though.............maybe a switch or relay type of 'thing' between the P94 and the rudder servos (bow and stern) so that command can be switched between either the bow rudder or the stern rudder, by a simple toggle switch on the transmitter?  Not my expertise I am afraid, so will need more thinking about....

[Howard]

Hi Carl,
Knowing you you,ll not settle untill its right and second best will not be good enough I know you,ll get it perfect in the end these things are sent to test us. If its not to big have you thought of making a cast of what you,ve got then fettle that till your happy and and its perfect in your eyes you could then cast a few at the time to work on till your happy with your master. just keep it coming as an enjoying the model being born.
                                                             Regards Howard.
                                           

[carlmt]

Spent much of today adding another workbench in the workshop, and when all this had been done managed to create the mould boxes for the skeg and rudder ready for the first pour of the rubber solution in the morning:
 

 
More tomorrow........

[derekwarner]

Hi Carl.......I am getting a little confused......with the schematic by DM and your comments ....

"maybe a switch or relay type of 'thing' between the P94 and the rudder servos (bow and stern) so that command can be switched between either the bow rudder or the stern rudder, by a simple toggle switch on the transmitter?"

1. I see the toggle switch in the + cable from the 7.2 Vdc battery pack to the P79.........am not sure why this S/W is there?
2. From your images I cannot see a bow rudder....but can see the hull marking for the thruster...........
3. However would have thought that the bow thruster and stern rudder would be totally independent?

Am I missing something?

Keep the build images coming along..... ..... Derek

[carlmt]

Hi Derek
The toggle switch in the circuit for the bow thruster is just to isolate the 7.2Nimh battery pack.
As for the bow rudder, unfortunately the outline of it hasnt come out very well on the hull - but its shape, size and position will be on the drawings should anyone want to make it operable.  The real ship had one but it was only used when the ship was running stern first into the port.
Yes, the bow thruster and the stern rudder will be totally independent of each other.
 
The dilema we have with the bow rudder is one of a lack of channels on a standard 4 channel setup. Left stick up/down would be main power, left stick left/right would be bow thrusters, right stick left/right would be rear rudder.  Using the right stick up/down as the bow rudder would not be intuitive.  My thoughts on introducing some kind of switch between the P94 and the rudder servo(s) would then allow the right stick left/right to be used for either the stern rudder or the bow rudder - depending on which way the switch is thrown.  Still need to speak with Mr Milbourn on this point........

[derekwarner]

Thanks  Carl.......

I understood the functionality of the 7.2V isolation switch [very bad phraseology on my part], however was comparing the 12V power off/on [3 wire] switch which is connected to terminal SW on the P107 circuit board

So having little understanding of the black arts wondered why this isolation was not on the RED wire from the 12V battery  .....

I have read a number of articles on single propeller driven double ended ferries where FWD rudder was disconnected and securely pinned  ....or never to be used again.......

Derek

[carlmt]

OK!!! Been busy in the workshop these past few days trying my hand at this resin casting lark 
 
Mixed success so far.  The silicone rubber moulds seem to have worked out ok....bit of a "xxxxx" separating the two halves of the split moulds in the beginning, even though I used the recommended spray wax release agent supplied, but they came apart in the end.  Cut the fill and air vent holes and then set to with the resin itself.
 
Boy oh boy do you have to work quick with this stuff!!! Whereas the silicone rubber took nigh on 24 hours to cure, the resin starts to go off in about 2 minutes!!!     You really have to have everything ready at hand.
 
Well, to get the first hull underway with the fit-out of the motors, electrics and drive we needed a rudder and skeg.  Additionally, there are a number of ventilation grilles on the hull which, on the model, are etched brass parts.  These need a 'backing' letting into the hull for the brass parts to fit to - and on the hull there are 4 vents with especially shaped splash guards.  These would have been too fragile made just from styrene so resin castings have been produced which have the splash guards and these then carry the vent grilles.
 

 
The rudder casting came out fine in the end.  It has the brass rudder shaft cast and embedded within the resin.  This is how it will be supplied in the kit.
 
 
 
The skeg, on the other hand, hasnt cast as well as I had hoped.  Not too bad, but a couple of air bubbles were caught in the corners.  It will be fine for the prototype hull, but I would like better in the kit.
 

 

 
Overall, I am not too displeased with this evening's efforts.  Need to sort out the venting issue on the skeg mould, but all else seems to be heading in the right direction 
 
Loads more parts to cast now....................... 
 
 

[Brian60]

Looking good so far Carl. I do have a concern with the brass and resin. When set up resin can be 'slippery' given enough time and use, it could be that when applying torque via the servo to the shaft, it will turn in the resin part rather than applying the turn on the blade.

To combat this either a 90 degree bend in the end of the shaft embedded in the casting or a straight shaft with a 'pin' through the shaft would work.

[carlmt]

Hi Brian - Thanks for the compliments 
 
Re your point on the brass rudder shaft - yes, I had heard this before.  The resin rudder does have the shaft bent at (almost) 90 degrees toward the rear to provide the turning force.  I say 'almost' as the first couple I tried to bend to full 90 broke off at the last moment!!!
Hopefully, this should overcome the problem...........
 
EDIT - Thanks for the tip of the pin through the shaft....I will give this a go on the second prototype.......

[warspite]

Or supply a propriety brass rudder (or construct your own version), this a brass plate soldered to the shaft, about 1/3rd the size and shape with holes drilled through, it acts in two ways, 1st the strength of the rudder is bolstered by the metal core, 2nd the holes allow the resin to pass through to each side to give grip.

[inertia]

Thanks  Carl.......

I understood the functionality of the 7.2V isolation switch [very bad phraseology on my part], however was comparing the 12V power off/on [3 wire] switch which is connected to terminal SW on the P107 circuit board
So having little understanding of the black arts wondered why this isolation was not on the RED wire from the 12V battery 
Derek

Derek
The switch on the P107 does not operate the main battery circuit directly. Rather it switches a small MOSFET on the circuit board. This takes a very low current and so can be used with a small switch. The MOSFET is the device which actually switches the main battery to the board. The whole point is that you don't now need to fit a great big ugly main power switch to the model or, more to the point, find somewhere to hide it. Mr Lewis of Component Shop is a cunning chap, too!

The drawing was done to Carl's later specification, which omits the stern thruster and bow rudder for the time being. It should not be too difficult to use a DPCO relay to switch the rudder signal from the stern servo to the bow; a modified P43 will do the job, operated from a 2-way channel and switching the signal and positive lines (white and red) from one servo to the other. The only drawback I can see is that both rudders must be centred while switching over. If we were to use a PIC device then this could be programmed to centre the functioning servo first, but we ain't gonna use that sledgehammer to crack that nut. I would hesitate before disconnecting the P94 from the steering command.

I'll speak to Carl as and when he wants to add that facility.

Dave M

[carlmt]

Quick update.........
 
Finished off the openings in the hull with the four vehicle deck extract grilles.  In the kit, these will be supplied as resin cast fittings for letting into the hull because of their special shape with the splash deflectors.  This would be very difficult to produce in sufficient strength for day to day sailing if just made from styrene.  To these can be added the etched brass grilles:
 
This shows the location of the vents on the real ship:

 
And this is the sequence of creating them on the model:
 

 

 

 

 

 
There are numerous other vents similar to these dotted around the hull and superstructure and they will all be treated the same way:
 

 
Finally the hull, motors, some of the fittings, shafts, props, electronic gubbins and numerous other parts were taken over to dad's workshop for him to set to and build the first prototype.  This first will be in the later colours of P&O when she was named Pride of Hythe and will use the previously built superstructure parts that were produced to test the theories asnd design of the laser cutting.
 
This shot shows the newly arrived hull with one of the superstructure 'modules' placed roughly in position:
 

 
Bearing in mind that these were built without the benefit of a hull to check fit and alignment, I can report that they fit the hull surprisingly well 
 
Back to the workshop now as I have something like 55 fittings to mould and cast 
 

[Ferry cross the Mersey]

Wow    She's really coming along now.


Superb job Carl, thanks for the updates 


Cheers Antony

[Howard]

Thanks for the up date Carl she,s realy looking good, Its going to look great on the water.
               Reards Howard.

[carlmt]

Paid a visit to the shipyard today to sign off progress on the machinery and propulsion installation before it became too late to make any amendments..........glad to report that all is well and the choices of the MFA385 motors with bases and the M2x10"long shafts seem to be the correct choice.  Obviously a full sailing test will prove the theory or otherwise!!! But so far, so good:
 

 
With the motors mounted on the floor of the hull, and the holes for the shafts cut in the marked locations, the shafts sit nicely horizontal.  An A frame is yet to be made for the ends of the outer shafts, but this is not structural:
 

 

 
I have been wracking my brain for quite a while to come up with a simple method of producing the proptube to hull fairings, but I think dad has hit upon the idea which will work and is so simple.  The idea is to take a length of 6.5mm plastic tube (which will slip over the proptube) and then shave an element off it until it forms a shape akin to a quill.  This is then slotted over the proptube and pressed up against the hull until it sits fair.  Following gluing in place, filler can be added around it to form a streamline shape, but it wont need much!! All details on how to do this will be included in the instructions:
 

 

 
A test fit of the rudder and skeg was made also....
 

 
I think we can say that it was successful 
 
By the time I visit next week, we expect all these elements to have been completed and fitted and a start would have been made on the deck and superstructure fitting.
 
Onwards!!!!!!!!!!!!!!!!

[Howard]

It,s getting better every time look Carl, keep up with the good work.
                          Regards. Howard.

[carlmt]

Cheers Howard    I admit, it is exciting to see something become 'solid' that, for many years, only existed in my head!!!
 
How are you keeping bud?  Feel up to working on the SD yet?

[cos918]

looks real good

john

[TugCowboy]

Absolutely fantastic seeing the development of something of this quality and the though processes that go along with it.
Please keep sharing.

Alex

[Howard]

No Not yet Carl just finding the mid-section tank top longitudinals a bit of a painas so many small slots on a very thin strip but still enjoying it if that the right word(lol).shoulders been a bit of a pain for the last few weeks, Once I get them done the the tank tops on  I,ll get the yard to send some photos.
                             Regards  Howard.

[derekwarner]

Carl......don't let those scale dockyard machinery fitters con you ....when they say...."an A frame is yet to be made for the ends of the outer shafts, but this is not structural": 

Don't let them pull your leg .....all A frames or P frames are load bearing to stop the shaft wallowing around in the water  ....

The logic  behind this is

1. if they were not structural, they would be considered cosmetic
2. a cosmetic element under water so looses all importance as only the fish would see it
3. why add to the vessel cost just to keep the fish happy?..............

I'd be tempted to ask to see the scale naval architect's qualifications  . or design calculations for these A frames...........Derek