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[JohnG]

I have a plan but have a few bits to do first before getting back to it properly. Real life things like a garden bench for a relation.

Yes real life does interfere with the modelling..... I’ve also got a friend to help with a bench next week - same skills just bigger and noisier tools!

[ballastanksian]

Yup, but just as fun 

[JohnG]

there's been some progress since the last post:


I made and fitted the davits (thanks to geoff for the advice), and modelled and 3d printed the whalers.


i decided to model the whalers  'covered' - as they are in most of the pics i found - also much easier to model - and lighter!

[JohnG]

also fitted the final set of stanchions along the main deck.

[JohnG]

so now she's pretty much complete for the main construction


Just a 'snagging' list to work through...

[JohnG]

Well that was an adventure too far - she sank!..... -  here's the sorry tale:

Inspired by visiting the recent wings n wheels show, i decided it was definitely time to take the model for a test sail - down at the poole park boating lake - she set of beautifully  - though a little lower in the water than i'd hoped.

The first few manoeuvres were fine. also tested the sound system which was good. - all going well so far..

I wanted to check the control range - so sent her off along the side of the lake. Unfortunately as she got to further away, contact/control was lost. 

Rather than stopping, she kept going and headed off along edge of lake with me in pursuit. She then managed a turn - and i thought i'd regained control. Not to be - instead headed off into middle of lake - and there gently sank!

i had no choice but to wade in to get her back.  For anyone that happens to be interested, Poole model boat lake is just under 3 ft deep!   

Fortunately all recovered ok. Boat and owner rather wetter than planned.
The picture posted is of the boat post- recovery. Looks ok on the outside!

i'm now licking my wounds, drying all out, waiting to see what electronics survived,
and thinking about lessons learned..... There are quite a few!!! Mostly from over- confidence of a new modeler….   i may post  some thoughts later...

[tonyH]

Bad luck John, I'm sure that more than a few of us have been through it and at least it was only 3ft!
 

[raflaunches]

Hi John


Sorry to hear about the sinking. Whilst I haven’t yet had a sinking myself I have come close on a couple of occasions but luckily spotted something was wrong before it went under. If you are using a 40MHz than I think that’s your problem with the erratic behaviour after loosing signal. Like Wicksteed at least the water level was only 3ft making recovery easier. You may find that a dry out may be all it needs to be okay. The brass destroyer that my Dad and I were restoring for a friend took five attempts to be relatively dry inside and it still tried to get water inside over the deck during hard turns! Don’t be too perturbed by the initial failure- my second run with my first boat ended in disaster when the power lead fell off the battery! Boat drifting aimlessly for an hour until we managed to get it close enough to the lake edge (this was at another lake where you couldn’t wade in as it was 20+ft deep!)

[JohnG]

Thanks for the kind comments. Tony and nick.
As you say Tony, at least it was only 3 ft!


The big things i learned were :
-The need to do a bath test first.  I’d thought i had some leeway (as ballasttanksian commented some time ago). Adding smoke gen, turrets etc definitely overdid it! Really should have checked…..
- i didn’t fully make sure the decks were flush. Had only been talking to Geoff at wings n wheels when he suggested vaseline to seal the deck. I didn’t! Will also think about bulkheads and foam or similar for bouyancy (as in other posts on mayhem that i read and ignored… )
- and i’ve been trying out control via Bluetooth to a raspberry pi rather than conventional radio control: until yesterday i thought it was looking promising: it was giving ok range that i thought i could boost, and a software mixer that worked beautifully for 3 motors.   Now have to decide whether to persist, or go to conventional rc….   I suspect the answer is conventional rc for the motors/rudder, and raspberry pi for the auxiliaries ( for anyone interested, i have smoke on/off, video from onboard camera, control of sounds of motor, bell etc, and voltages of the batteries, all sent from the pi to a tablet.)


Anyway, time to go back cook some humble pie,  and dust off drawing board…

[Geoff]

John,


Very sorry to hear of your troubles. If the water was fresh then there is a very good chance the electronics will survive. I lost a 6 foot battleship many years ago in deep water. It plunged like the Titanic! Got it back and washed all the electronics in fresh water as it gets rid of mineral salts. In the event the only permanent damage was to a couple of servos.


I would counsel you consider very carefully where the water came in and how to stop it. Sounds obvious and simple but its not necessarily where you think, for example on tight turns did the deck become awash, or did you loose control because the water had already reached the electronics through another route? That would also explain the loss of control?


Fortunately the model itself does not appear to be damaged.


Unlike model airplanes we have a fair chance of getting the model back in one piece!


Keep up the good work.


Cheers


Geoff

[Geoff]

As an add on, maybe float the model for a couple of hours in the bath to see if there is a hidden leak somewhere

[tonyH]

Geoff is right about the fresh water etc. but one caveat he hasn't mention that often occurs with models of pre-WW1 powered warships is that they have a mind of their own. They sink, fall over, don't stop, don't steer etc. and generally follow the same problems that some of the real-world designers faced. Too late of course. That's what makes them so much fun when you find that it's not your fault! 

[C-3PO]

If you still have any wet electronics place them in a sealed bag somewhere warm with some uncooked rice which should draw out/absorb the moisture ...

Regards
C-3PO

[JohnG]

thanks guys. all useful to hear.   


I'm leaving it all to dry thoroughly before i carefully test the bits to see what survived.
(also got grandkids around this week for the first time for a year - so modelling  takes second place for a while...)
i'd heard the 'dry rice' method - though i have to say in a  recent test with an iphone   it didn't work 
(that was my better half - who having done that to her phone, seems a little less sympathetic to my adventure than i thought appropriate!)


yes geoff, as you say, knowing where the water went in would be useful - the trouble was she was too far away to be sure. i think probably waves over the bow due to being too low in water, but not 100% sure.


and Tony, that's an interesting comment - hadn't thought of the stability of the original being a contributor...      sadly as i think i said, mostly it was my fault - but yes it's part of the fun - though standing in the middle of the lake hunting for a sunken it didn't feel like it for a few minutes!! Thanks for the encouragement.

[tonyH]

It get's into your blood John,
If you want to see what goes, I've two threads on "experiments" of mine that looked right but were disasters. One was a Thornycroft jet drive torpedo boat from about 1890 which died sinking slowly at Mayhem. The second was the notorious "Fat Pointy Thing" which was a French Destroyer of about 1896. Apart from ramming the lighthouse at Mayhem in about 2011 it was impossible to drive. If you have a spare hour it may amuse you to look out that thread in particular.    

[warspite]

I would watch QI where they debunk the idea of using rice to draw water out of electronics - apparently it has no effect as pointed out above

[JohnG]

hi tony,
well thanks for that diversion - i found the 'fat pointy thing' thread - longest debate on the purpose of bowsprits i've ever seen! but martin's description of the outing at wicksteed - priceless. 
(it's here for anyone minded to look  https://www.modelboatmayhem.co.uk/forum/index.php/topic,17389.225.html   )
seems it can be summarised as 'need to buy a bigger lake'...  and clearly you had an audience - which was thankfully missing from my adventure.

[tonyH]

Hi John,
It was fun I must admit but it went to prove a couple of points about " not my fault!". The build was straight from the original drawings where the rudder was ahead of the props. Jimmy James was a master mariner who had literally sailed the seven seas in command on sail and steam so when we tried to sail her at Eaton Park she was fully manned with coxwain and engineer on wheel and independent engines. Nothing we could do would induce her, on a flat calm, to be controllable. The original design just had to be unworkable to any large extent but 18 were built of the Arquebuse type plus a number of others of other nationalities. I've attached a pic of the design model of Turbinia at the Science Museum with the same layout but which does not appear on the real vessel. So definitely not my fault! The more interesting bit was the fact that the "Pointy thing" itself actually worked and when she hit the lighthouse it slid back correctly against the friction mount so I can only think that the French Navy knew the control problem existed and designed in the bumper. It also appears on Russian and Japanese destroyers of the same period since many of  their ships were heavily influenced by the French. Again...Not my responsibility!  So build away and blame the designers!
Cheers
Tony

[Railbob]

If anyone is interested Drachinifel has just posted a video on Broke and Swift , very interesting.

[Plastic - RIP]

Is it worth filling all the spare space with floatation to stop this happening again?

[tonyH]

First it's a case of sorting out where in the hull the weight actually is and why, if indeed it is, leaking per se. or whether it's because the boat is a combination of too tender and unsealed.

[JohnG]

Bob, Many thanks for pointing out the Drachinifel video about the april 1917 dover strait action

(it's here if anyone's looking: https://www.youtube.com/watch?v=r2Be3jr45Ro )

My great uncle was killed in the action, so it's of considerable personal interest and what inspired the model. Overall Drachinifel is pretty accurate and a couple of snippets i'd not heard. (though Broke was built by Samuel White as 'Almirante Goni' not Vickers Armstrong - her 4in guns were made by Armstrong Whitworth. )
Remarkable to think of hand to hand combat with cutlass and bayonet during a destroyer action in 1917. In his papers Evans refers to losing 7 rifles and bayonets over the side "with Germans attached" - desperate stuff. 

And regarding stopping the sinking reocurring i think tony's right  - the first things i need to do are get the weight/ballast sorted and improve the seal. Flotation as a last resort might be possible, but it's secondary.

[JohnG]

Broke –  - now fixed!  - The Relaunch
 
Pleased to report that Mayhem at Wicksteed gave a super deadline to get HMS Broke back to working order.
I have to admit work had rather stalled since the sinking last year (see earlier post).
Anyway lots of rewiring later, a change to more conventional RC, and I was very happy to have her on the water.
(preceded by a bath test and a test in a friend's pool - lessons learned!!)
I abandoned the attempt at moving turrets. Just too heavy and ambitious for now.
The rest of the electronics – camera on bridge, smoke on/off, and sounds all worked fine – though sound volume leaves something to be desired.
I was particularly pleased that the 3 motor mixer using a cheap raspberry pi pico gave good control and manoeuvrability. i'll post something about it in the 'microprocessor control' section.
A great pleasure to meet other Mayhemmers at the weekend and put faces to mayhem names…

[ballastanksian]

Broke looked a treat on the water John. It was lovely to meet you and hear about your woes, the return to action of Broke and the ideas that you had for her. I think that trying out a new idea on each new model allows you to test it in isolation, not distracted by other new technologies.

HMS Broke gave you the chance to design and print the hull, and to learn from that process. Next time, you can try out ideas for moving guns, now having got the hang of printing a hull. Then maybe a gun fire system or other could be tried on a further model! But a hobby is individual as the individual doing it, so take your time and don't fret if you are not meeting deadlines. These come from the world of work and have little place in a hobby except for such occasions as the person WANTING to get it done.


Cripes, we all have projects that have hung around for ages. Too many can be depressing, but two or three is good to allow you to chop and change as you wait for materials or enthusiasm or inspiration to solve a problem. Geoff spent months and months on his gun fire system and even had a couple major redesigns.

[Sealord]

  Hi John, excellent work on the model, the only complicated bit is the programming to do the 3D printing, well it is for me,,
      Best wishes and thanks for posting the thread, very interesting..