First Sail of 2014 – A Wonderful Hobby

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3 January 2014 at 10:49 #4066
David Butler 3
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@davidbutler3
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3 January 2014 at 10:49 #46053
David Butler 3
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@davidbutler3
Grabbing the nearest boat (and the family!) and heading off to the boating lake (Woodbridge) on a sunny day is a great way to start 2014. And it reminds you how our hobby attracts great conversation; almost immediately I struck up a conversation with Stephen about his yacht, and a crowd of youngsters with questions about my Lego Boat (a Fairey Huntsman hull with a planked top and Lego baseplates). A really fun afternoon and a renewed goal of finishing all those partial completed models – next one is the Anteo Tug. Have a fantastic 2014 everyone!

Oh and I do have a question – the Lego Boat sits far too high in the water (its maiden voyage) but exactly how much ballast do I need?
3 January 2014 at 11:09 #46055
Malcolm Frary
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@malcolmfrary95515
There is a school of thought that says that a boat is only too high in the water if it is unstable. After that, use the TLAR principle. (That Looks About Right). Best way is to add batteries* as low as possible until satisfied with the appearance, then wire them up for either more run time or more performance.

*If batteries are not available, Bean tins work very well, weigh them when happy, look for that weight of battery, or, as a last resort, ballast.
3 January 2014 at 11:16 #46056
David Butler 3
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@davidbutler3
I did have some concern when turning as to the stability – so it's a matter of some trial and error. I have a bag of lead shot so can progressively add some and then re-test. I suspect there's a point where the additional weight has no benefit?
3 January 2014 at 11:18 #46057
IAN_I
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@ian_i
Hi Dave..

Malcolm is right.. the bath test.. with weights and looking about right.

You could also look up, on the internet… the Block Coefficient…!

LXBXD

Length x Breadth x Depth.

The egg heads on hand here may be better to advise than me …. ( newby).

Best regards and happy new year,

Ian
3 January 2014 at 21:29 #46061
Amy jane September
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@amyjaneseptember49770
Hello David, and a happy new year! You're more lucky than me , been blowing and raining here! The lego boat looks great, though may I add, she looks a little bow down too?

Amy jane
3 January 2014 at 22:24 #46063
David Butler 3
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@davidbutler3
We had one good sunny day on Thursday so we grabbed any boats we could and rushed to the boating lake. The Lego Boat had just been finished the day before and this was the first time in the water with power applied. So the way it sits in the water is wrong and quite alarming when turning. We had some interest from a couple of children (probably about 10 or 11 like my son) and they had a go with the transmitter with the understanding that if it went down they agreed to wade in and get it! (it's a raised facility with concrete walls that is less than 1 metre deep). It was a really good way to start the new year – it's been windy and raining ever since!
4 January 2014 at 15:36 #46077
ashley needham
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@ashleyneedham69188
David. Lego is very heavy for model boats and with such a large and heavy superstructure so far forward its no wonder it leans a lot. You may have to add more ballast than is right for a hull of this sort, or put in some windows and lose a few bricks.. could try substituting one row bricks for two row ones to also save weight?

Ashley

Edited By ashley needham on 04/01/2014 15:37:25
4 January 2014 at 20:06 #46080
David Butler 3
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@davidbutler3
1,900g for the boat with 7.2v battery installed.

600g Lego at the front

250g Lego at the back

My son tells me that he will re-design the Lego superstructure tomorrow – job done then…..
5 January 2014 at 20:52 #46128
David Butler 3
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@davidbutler3
What didn't go to plan is that the twin motors are water cooled (by adding cooling coils to the Graupner 600 motors) and there is no flow of water at all.

The brass pick-up is in front of the rudder and should scoop up water which passes through the coils and out at the side (shown just above the 'Z3' markings in the photo). This was really just for show as the motors already have fans in the back and don't get that hot. Indeed just the extra heatsink effect of the coils helps more than the water.

So I hunted around this afternoon and added a small pump which now sucks in the water, through the coils and out the side using a Turnigy RC switch connected to the AUX channel. This channel is mapped a button on the DX3R transmitter – press once it comes on, press again and it is off. Tested in the pond and it looks good.

Next I need to buy some lead weights – luckily there is a shop near where I live so I'll visit tomorrow after work.
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