Calypso motor and ballast queries

[Nick LewisParticipant @nicklewis66033]

Hi Folks,

Be gentle with a newbie, please …

I'm just starting on a Calypso build, and I've just seen Bryan's thread which has raised questions in my mind. Rather than hijack his thread, I've started another. Hope that's OK.

My background is mainly in railway modelling (N gauge), RC aircraft and injection moulded aircraft. I built a couple of semiscale RC sports boats for my son when he was young, but that's all. I appreciate that Calypso is a big task, but I've always wanted to build it, and had it in my stash for a while. Too much of my youth was spent entranced by Jacques Cousteau's Undersea World, I think. I'll grapple with the modelling challenge, win or lose (!), but I'd really like some advice on the marine-specific side of it.

Reading Bryan's thread, I'm worried about motor choice and ballast. Cornwall Model Boats have recommended fitting Mabuchi RS545's powered by a 7.2V NiMH pack, but I see 385's being talked about here. The 545's are each about 130g heavier than 385's, and the mounts will presumably be heavier too. So I'd be adding some 250-300g at or around the waterline by fitting 545s. Is this necessary/wise? (Billings don't specify motors, but the kit plan shows motors a lot smaller than 545's. More like 385's, as far as my limited knowledge goes. I've no idea what the performance implications might be.)

Second, can someone advise how much ballast I need? And where I should place it?

At the moment, all I've done is glue in the keel, so I have full access to place what I want where I want it. I tried floating the hull in the bath, and flooding it with water, which indicated it should displace around 3.5kg when floating at the designated waterline. But that was a bit of a rough and ready exercise since simply flooding the hull didn't float it level. I haven't yet tried to work out what the unballasted weight of an assembled model might be. Being from an RC aircraft background, I tend to build light, but I definitely take note of everyone's concerns about topside weight. Obviously I don't want her to turn turtle, but I don't want to overload it at this stage either, or be left with no margin to trim it level when built.

Any advice will be most gratefully received.

Nick
P.S. I gather there's a recent Model Boat issue covering ballasting. Which issue is it?

[Nick LewisParticipant @nicklewis66033]

[Colin BishopModerator @colinbishop34627]

Welcome to the Forum Nick. While you could use 545 type motors, they are really bigger and more powerful that you need for this model. As suggested in the other thread, 385s will do the job perfectly well and you could up the battery pack to 8.4v to give a bit of extra oomph should it be needed.

As far as how much ballast is needed, the simple answer is 'enough'! The amount will depend on the weight of the rest of the boat and its positioning will be where required to ensure the boat floats level. At your current stage of building both will be variables depending on how much weight you put into the structure of the boat and where you site the motors and batteries etc.

As you will have gathered, the most important thing with this particular model is to save weight wherever you can above the waterline and to ensure that the batteries and any additional ballast are kept as low in the hull as possible.

I am not familiar with the details of the superstructure of the kit but any weight saving you can achieve by removing unnecessary or hidden material can only be a good thing. I'm not sure what the helicopter landing pad is made of but consider substituting something lighter if that is feasible. Another technique is to use the supplied components as a pattern for a more lightweight item. No, you shouldn't have to, but, as you will have gathered, this is a very sensitive model when it comes to stability.

Colin

[Nick LewisParticipant @nicklewis66033]

Hi Colin,

Thanks for that.

I think I'll go with the 385's…

I repeated my flotation experiment this morning with weights I could place more carefully around inside the hull, and found that she displaces 3.54kg when floating at the marked waterline, and needs excess weight at the bow to float level. Surprisingly, my "rough & ready" attempt the other day was more accurate than I thought! The model itself weighs in at about 2kg as best I can estimate with all the parts still in sheets and on sprues etc. Plus obviously glue and paint and so on.

Radio, battery and motors look like coming out at about 600g. Which would leave a tad short of 1kg available to ballast her. I thought what I might do is build up as many of the deck based sub-assemblies as possible early on to see how much they weigh in at, so I can get a better idea of how much ballast may be needed. Then try and get a good portion of it buried under the motor deck around the keel, but leaving myself some margin to trim her.

The superstructure is a mixture of materials – I don't know how much can be cut out yet. I doubt I can do much with the landing pad – it's styrene girder work with 1.8mm obeche planking for the pad itself, and wood supports. There's no brass in it as far as I can see from the plans.

The things that I have noticed shouting out to be replaced at the moment are half a dozen oil drums that are supposed to be placed at the edges of the top deck. i haven't weighed them, but they feel as though they may be solid brass, so plastic alternatives might be a decent saving if I can find some!

What fun!

Nick

[BRYAN ASTONParticipant @bryanaston57723]

Greetings Nick

Good luck building the Calypso, the detail is amazing when built. I bought one already built, it needed a spot of T L C having spent years as a static model, Mine is an early model, as the years went by there were a number of updates.

Regarding the stability problems it is surprising how much ballast is needed, I have just completed a magnetic attached centre keel, I will, when the weather warms up , relaunch it and see what happens, wish me luck

The correct motors are indeed 385s.

Bryan

[Nick LewisParticipant @nicklewis66033]

Hi Bryan,

I do indeed wish you the very best of luck! You don't want a repeat of that experience!

385s it definitely will be! I think it's going to take me a while to build this beast, but hopefully it will eventually reach the water… I'll be needing the luck, then!

Can I ask how your superstructure is secured and what access you have to equipment? I don't know if I'm missing something on the plans, but there doesn't seem to be anything to cover getting into the boat after you've built it….

(I may be showing my naivety about matters marine, of course. If so, I apologise! )

Nick

[BRYAN ASTONParticipant @bryanaston57723]

Nick

The bridge is glued to the deck and cannot be removed,however the superstructure aft of this and the helecopter deck is removable and just rests on the hatches, plenty of room for the motors ,electronics.,ballast and batteries.

The twin rudders are covered by the rear deck and are tricky to get to, but not that difficult.

I am glad that I bought one already built I don't think I would have had the the patience to build one.Keep us upto date with the build.

Regards Bryan

[Charles OatesParticipant @charlesoates31738]

Hi Nick, I don’t want to post other peoples pictures on here, but there are some on the web that may help you. Some show peoples arangement of the internals, and how things are arranged. Google billings caslypso, and select images, rather than web pages, that should do it. I agree with the choice of 385s for power, the Calypso in our club uses them on 7.2 volts and has more than enough speed, he usualy runs throtled back and saves the extrs for emergencies. His model has all the sugestions quoted here, lightend uppers, and ballast, batteries etc as low as possible. It runs very nicely.
Chas

[Nick LewisParticipant @nicklewis66033]

@Bryan

Thanks for that info. It hadn't occurred to me that it would be OK to just leave the superstructure rest. What happened when she rolled over? You were lucky not to damage/lose anything – there's a lot of delicate bits on her..

I hope I've got the patience myself. I'm going to view it as building a floating model railway layout. (The trouble is of course that few layouts are ever truly finished!)

@Chas

Thanks for that – it's good to know someone has been successful.

I'll definitely try the image search. I found a long thread on another forum, but a lot of it is about super detailing her, which I don't think I have the heart or expertise for, and sounds as though it's likely to add all sorts of unwanted weight anyway.

[BRYAN ASTONParticipant @bryanaston57723]

Nick

When my boat overturned the hele.deck floated away and the the large superstructure with the funnel and rubber dingy also floated away, eventually they reached the edge of the lake and I recovered them all undamaged.

All electronics, motors and batteries found a new home in the rubbish bin, the boat was salvaged a week later and over the next few days some of the deck equipment came unstuck including the bridge but they have now been glued back. I was very lucky apart from the electrics nothing was lost.

The only thing stopping a relaunch is trying to find a suitable adhesive to stick two metal strips to the underside of the plastic hull to grip the magnetic keel if it is needed. Anyone out there got a a suggestion.

As I have said before my next option is use the boat as a Viking funeral barge.

Regards Bryan

[Nick LewisParticipant @nicklewis66033]

Bryan,

You were lucky. Well, as lucky as possible in the circumstances.

Slow-setting epoxy? Presumably the adhesive'll have to hold a reasonably substantial weight from the keel, plus take the stress of detaching it.

I presume you can't access a suitable area to secure the strips inside the hull, so that the stress pulls them tight rather than loosening them?

Nick

[BRYAN ASTONParticipant @bryanaston57723]

Nick

With the lower deck you cannot get to the keel inside otherwise gluing the steel strips inside would be too easy.

Once the boat is built be very careful how you handle it ,every thing is very fragile, it was designed to be a static model not a working boat. Always carry a bottle of thick superglue when you sail it.

Regards Bryan

[Nick LewisParticipant @nicklewis66033]

Bryan,

I thought as much. That's why I'm trying to work out how much I can afford to pack under there before fixing that deck down.

It is going to fragile, isn't it? Vacforms everywhere and lots of bits sticking up!

Nick

[Nick LewisParticipant @nicklewis66033]

Hi All,

I thought I'd post an update on the build…

I weighed the oil/fuel drums. 110g for the six. It doesn't sound a lot until you realise that it's >5% of the entire weight of the model in six tiny decorative fittings on the outboard edges of the top deck!

I did indeed start by building the various on-deck assemblies. So far I have a funnel, three masts, a foredeck mast/hoist, a diving chamber, the inflatable, the tender and most of the heli-deck ready for painting. It's going Ok so far.

I've never built anything from Billings before, but it's a little frustrating. I accept that Calypso is designated for "Expert Modellers", (so what am I building it for? ) but a few words of guidance would have been nice. The worst part is that the booklet of plans of various assemblies contains a number of1:1 plans. Excellent. If they were 1:1 it would be, anyway. They aren't. They are slightly too small, and what's worse, their aspect ratio hasn't been preserved properly. I presume something has gone wrong in the final print formatting. And they don't entirely match the moulded/CNC parts supplied anyway, and not all essential measurements are called out… Which is making cutting parts from supplied stock interesting to say the least!

Especially since someone put Ebenezer Scrooge in charge of packing the rod and strip materials. The worst example so far was a piece of 2mm brass tube out of which I had to cut three pieces. Total length of the three pieces, 147mm. Total length of supplied stock, 150mm… Perhaps Billings use graphene saw blades or something, but for us mere mortals with real blades with an actual thickness, that was a tad close for comfort!

Anyway, it's going OK. No disasters yet. I'm enjoying it and looking forward to that (distant) day when she sails…

Nick

[BRYAN ASTONParticipant @bryanaston57723]

Hello Nick

Just a bit of info. for you ,according to Billings if you are intending to sail the Calypso the minimum ballast required to keep upright is 9 lbs or whatever that is in kg, I wish I knew that when I first launched mine,

Regards Bryan

[Nick LewisParticipant @nicklewis66033]

Hi Bryan,

Thanks for this info.

Can I clarify something? Did they say that it needs to be ballasted to 9lbs, or that it needs 9lbs of ballast?

The I'm asking is that 9lbs is a little over 4 kilos. That's not a million miles away from the 3.5kg displacement that I found would make it float at the scale waterline – it'd just be a little low. But if it needs 4kg of ballast on top of the 2kg weight of the boat itself, it's going to be pretty low in the water, I suspect.

Thanks again

Nick

[Malcolm FraryParticipant @malcolmfrary95515]

Perhaps the wording on ballast should have been "ballasted to 9lb", rather than adding 9lb to the boat.

[BRYAN ASTONParticipant @bryanaston57723]

Nick

As I read it the boat needs 9 pounds of extra ballast over the basic weight of the boat in in the kit, Remember the boat was designed as a display unit. If lit looks too low in the water you can always take some ballast out.

If you don't have the ballast correct it will capsize easily if the wind is too strong or gusty,trust me.

Regards Bryan

[Nick LewisParticipant @nicklewis66033]

H Bryan,

Indeed, but I'm just a bit worried that it'll then be so low in the water that there'll be a danger of swamping… It's the best part of 6lbs more than would have it floating at the scale waterline. It's not a lot short of doubling her displacement.

Is this in an email from them or something?

Because I've been concentrating on making deck subassemblies, I still haven't fixed anything else into the hull yet. I'll try loading her up to 13lbs or so and see how she floats. I probably won't be able to do that until the weekend, though.

Thanks

Nick

[Colin BishopModerator @colinbishop34627]

Assuming that the kit is reasonably accurate then it is possible to work out the rough displacement or weight of the model by reference to the stated scale by Billings of 1:45.

Displacement of the original ship was 360 tons but as it was built in America, operated by the British and then by France I'm not sure whether that is short tons (US), long tons (UK) or metric tons (France)!

In UK pounds the 360 tons equates to:

720000lb (US)

806400lb (UK)

793400lb (metric)

Scaling down by 1/45 x1/45 x1/45 you get an all up model weight including ballast of:

7.9lb (US)

8.84lb (UK)

8.81lb (metric)

(unless I've pushed the wrong buttons on the calculator!)

The UK measurement of 8.84lb is very close to the 9lb quoted above which suggests that the kit should be sailed with an all up total weight of 9lb. So don't put 9lb of ballast into the model unless you want a real underwater research ship!

Colin

 

 

 

Edited By Colin Bishop, Website Editor on 12/03/2015 15:19:52

[BRYAN ASTONParticipant @bryanaston57723]

Nick

I got the 9lb figure from a model boat forum on the web which was discussing the Calypso, I think it was a USA website.

Have got my Calypso down to the waterline by adding 1 kg of lead shot, under the bottom deck,three or four pieces of lead flashing size approx. 3inches x 2 inches two other strips of lead to the side of the bottom deck and three 7.2 batteries .

If you read my forum queries under Bryan Aston I listed all the ballast, I will have another look for the website if I can find it,

Happy boating

Bryan

[BRYAN ASTONParticipant @bryanaston57723]

Nick

I found the website it is called RCG Plus.

I read it again and the boat should be ballasted to 9lbs total, it states that the hull is 2lbs I have never weighed mine, have a look at the website if you have time, it is very long

Regards

Bryan

[BRYAN ASTONParticipant @bryanaston57723]

Nick

I have just weighed my Calypso with Two 7.2v batteries and all equipment on board and it totals 10 pounds in all, Once I have repaired the steering linkage which has come unhooked , I wish I had smaller hands, I will again attempt to relaunch the boat ,with crossed fingers,

Regards

Bryan

[Nick LewisParticipant @nicklewis66033]

@Colin,

Thanks for that. So obvious once someone points it out!

I think the 360 figure is short tons. I have the Cousteau/Sivirine book on Calypso and that gives it's displacement as 324 tons (light) and 402 tons (full load). It's a US-published book so they'll be short tons.

360 tons could be a rounded average of the two as a general loading. Or, I suppose it could be 402 short tons expressed in long tons.

Oh, who knows??

Nick

[Nick LewisParticipant @nicklewis66033]

@Bryan,

Yes, I know that thread. I wondered if that was it. It's a huge thread isn't it? Mixture of ordinary builds, super-detailing and scratch building…

Ok, looks like I need to be somewhere round the 9lb mark or so. Where is yours now floating to? The red/black boundary on the hull?

Good luck if you sail her this weekend!

Nick

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