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[John W E]

Hello there Dan


I am wondering how heavy the superstructure of your model actually is?  I am wondering this as I do know I had issues with the model Type 22 which I built with stability - but - this was my own doing as I had left the frames in the hull too high - therefore any batteries which I put in it were at least 3/4" higher than the flat keel to start with - and - this is why I added lead shot to enable the weight to be very low in the hull.


The superstructure on all of my models are made from plywood of various thicknesses from about 1:64 to about 1:16 thick.   Also there are various white metal and resin fittings on them.   I hasten to add I have never used a 'solid' resin funnel.  I have never had any issues with stability ever.


On the type 42 I used to do what I call a 'roll test' where you can twist the boat over onto its side until the water was up onto the main deck.  Then I would let go of the model and it would right itself.   To watch it roll back and forwards was quite nerve racking - but satisfying to know that if it were in the middle of the lake and you did too sharp of a turn the model would right itself.  The only model I have ever had which was 'worrying to watch' was the 1:72 scale HMS Daring from WW2 which was a very narrow hull.  In a straight line it was similar to a guided missile - it would run straight and true - but when you tried to turn it whooooaaaa even with independent control props - I am sure I saw her red bottom a few times.


So, check the weight of your superstructure - building in plastic may not be the lightest - I do know a lot of people build in plastic and encounter no problems whatsoever with stability issues.   


It would be interesting though to see if someone has built a superstructure for a Type 22 from wood and compare the weight difference.   Sadly, I cant, as the model I built has sadly long gone to a new home somewhere .


Have a look at the superstructure of the Type 42 that I built - and it is very compatible to yours as in size.


John

[Dan]

Hi John,


I just got the scales out, 478 grams for the main superstructure and 160 grams for the funnel and it’s superstructure. I can’t weigh the main mast because this Is permanently fixed to the deck but I’d estimate 100-120 grams. I forgot to answer your question in your previous reply, fortunately the funnel is hollow so not much weight in it fortunately.


When I get the lead shot I’ll try the roll test, but at the moment I have zero confidence it would right itself and 100% confident my pond fish would have something new to swim around 


From what everyone has said, I’m confident I can sort the issue as all the running gear and ballast will be sat directly on the floor of the hull.


Going from your photo I bet your type 42 looked fantastic! 

[John W E]

Hi ya Dan


That weight for the superstructure sounds about right; As a last resort I suppose you could lift the black waterline maybe 2 - 3 mm higher; or make the black bandit or the black plimsoll line whatever you wish to call it a little bit thinner and as I have said a little higher up.    This will give you a little more wiggle room for weight and nobody will know any different in the middle of the pond.  (Nobody's eyesight is that good   )


When I get my work bench free of rubbish (which it isn't at the moment) I will bring down HMS York and weigh the superstructure just out of curiosity.  Here is a link to the build, if you are interested.


By, doesn't time fly - it was 2009 when I built this one


TYPE 42 BUILD - HMS YORK (modelboatmayhem.co.uk)


John

[Dan]

Hiya John,


That’s always a option no one would ever know 


I just had a read through your build, thank you for sharing! Some very useful bits in there and inspiring to have a go at building with wood opposed to plastic although I don’t have the skills to build my own hull... yet.


You started building your type 42 a year after I started this one... it’s about time I got it finished 

[warspite]

Shot versus sheet ?


If shot is small balls and as an experiment -take two similar sized spherical items and compare them pushed up against each other.


Would not sheet be better as there is no gaps between to push weight further up, I know the resin fills this gap but is not as heavy as the corresponding lead, so would the weight be more concentrated as a mass and take up less space, therefore lower, if a Plasticine copy of the area was taken that the shot or sheet was going in, melting x weight and y weight, and then pouring the corresponding lead into the same shape negative mould in a suitable material would produce a virtual solid lead mass that could be removed when necessary.


Just me thinking inside the box, ignore if complete nonsense.   

[rnli12]

Good point. I have sheet and shot 

[warspite]

SO, not complete nonsense then, I know it will be just grammes but, 50g lower than the shot may make a big difference - discuss

[Dan]

When I was messing about with the boat on my pond, trying to get a rough idea of weights and locations, it only took very small repositions of each weight to make a noticeable difference to the stability of the boat. I think I mentioned before these were fishing weights and two lead acid batteries so the weight was not as low as could possibly be compared to if I use lead sheet or shot.  I assume sheet would give me more weight in a smaller area and lower than the shot might, so I guess that it could make a difference. I might order sheet and shot and try both and see what happens. Thanks for the suggestion 

[John W E]

Hi ya Dan, hand on heart I have tried a lot of methods of weights, varying from lead shot, lead sheet, water in bottles, old window sash weights, and a few other mysterious things.   To be honest with you, make sure your weight is as low as possible - it doesn't matter what the weight is/how it's made up.


Somewhere on here, there is a great discussion about adding weight to models - where too much weight in the hull at the bottom makes the hull react very quick and it rights itself to the vertical and over responds.   The answer is to actually add weight higher up the model - so that the model rolls slowly and more realistically.  This has a correct name (but me mind is on melt down trying to sort out an electrical problem).  Do a search on this forum and you may find the topic. 


John

[BrianB6]

I made my lead ballast from car wheel balance weights found over a period of time in local gutters.  I made a plastacine mould of the shape needed and then cast it in plaster which was allowed to dry for a week (Very important)

I then melted the lead in an old saucepan over a camping stove out of doors (Also very important as lead fumes are poisonous) and poured the melted lead into the plaster mould.
The weight was only to correct a small imbalance but can be used for larger pieces.
 

[dougal99]

For my own edification I decided to see what the difference was between the same volume of solid lead and lead shot.  I filled a container (old yoghurt pot weight 5 gms) wth water and weighed it to get the volume in my case 142cc. This gives a solid lead block of 1611.7gms (lead 11.35g/cc). I then filled the empty pot with lead shot, weight 980gms a 65% difference. So where space is tight solid lead would be preferable for maximim weight.[/font]
However, for ease and speed lead shot in bags is still my preference. As Brian86 has said, making a mould takes several days as the  plaster has to be very dry before you pour molten lead into it. Whereas, filling a bag with shot takes seconds. Further, bags can be added, if required, to hard to get to areas even after the deck has been fitted.
I have used both methods shot and sheet. I have also melted lead in the past but found it a faff, not to say a slightly dodgy process.

Just my thoughts.
 

[Dan]

Thank you guys, that's all very helpful information. I'm suprised by the amount of difference between the weight for the same volume. Obviously I expected it to be greater, but not that much. Handy to know if your strapped for room!

Im still in two minds what to go with, I'll have the room to use shot in bags so for now I think I can get away without moulding any for now

so after your point about the boat righting too quickly John, perhaps as the bags won't concentrate all the weight flat to the hull, they'll have a bit of depth with them, maybe preventing the rapid correction? I might be completely wrong.. I'll post the results when I get the time to do it

[Dan]

Very slow progress again unfortunately. However I've just finished making my rudders. Originally the running gear came with some stunning machined metal rudders. However over the years I've misplaced them. After trying to source replacements with no joy, I decided to make them. Externally they are plastic card made to the correct shape. Then filled with high strength resin. Will they be suitable and work, I don't know. But I'm going to try it.

[frogman3]

HI Dan nice to see you back modeling again as i thought you had packed it in but im pleased to see you havnt as i like campbeltown an i dont know where my one in 1/72 scale is now as the chap who bought it off me has sold it so i heard but he put it on u tube an i think its still on there with all the workin features goin in his livin room but dont know if he ever sailed it
ATB
chrisb 

[Dan]

Thanks Chris! I don't think I'll ever stop as such. Trying to balance work and family does mean my progress will be very slow now though. Those rudders were completed over a week where as before they'd have been completed in a few hours minus the epoxy and paint drying time. Im still weighing up muly options for my next build 


I do still see your Campbeltown pop up on YouTube every now and then. Hopefully it's still going strong!

[Dan]

Last night I stripped and refitted the running gear in hope to have the ship in the water this weekend. It was promising but but I failed to get a failsafe working. So I might have to postpone it for another week.


Other than that, a few small bits of detail have been added and I'm fairly happy with how it's looking now, apart from the colour of the decks. I'm in two minds to paint them a darker grey. All I'll be adding now are some deck decals around the weapons when they become available in the shops and the lynx heli when I build the rotor head. Then I'll consider it done.

[Dan]

It's only taken 15 years but today it finally had its maiden voyage    I'm glad I decided to restart the build as it's rekindled the spark. I'll admit it felt good to see it move off for the first time since completing it.


The 380 motors gave it a really nice looking scale speed and considering its fairly long and narrow, it had a relatively good turning circle. There's a few minor things that need addressing for next time. Unfortunately a loose coupling ended play early today. But regardless, it's seen the water and sailed well.


Now that this one is completed to a point I'm happy with, I've started putting things together for my next build.


Cheers, Dan

[warspite]

sounds like POW all over again - did you damage the rudder as well?

[Dan]

I thought the same, but fortunately not, and I'll get it sorted alot quicker too 

[warspite]

wish I could build to your standard as well 

[frogman3]

HI Dan very well done an she looks good on the wet stuff an whats your next build goin to be ?
chrisb

[Dan]

wish I could build to your standard as well 

Thank you for the kind words!

HI Dan very well done an she looks good on the wet stuff an whats your next build goin to be ?
chrisb

Thanks Chris. It's more than likely going to be HMS Ocean the landing platform helicopter ship at 1:96 scale. That will bring it in at 2114mm length and a beam of about 360mm. I'm not sure if I'm being ambitious or stupid, but it'll be my first scratch build, and like you, I'll probably build it with a split hull for ease of transport.


Cheers,


Dan

[frogman3]

Thank you for the kind words!


Thanks Chris. It's more than likely going to be HMS Ocean the landing platform helicopter ship at 1:96 scale. That will bring it in at 2114mm length and a beam of about 360mm. I'm not sure if I'm being ambitious or stupid, but it'll be my first scratch build, and like you, I'll probably build it with a split hull for ease of transport.


Cheers,


Dan

WELL Dan how big a car have you got as a hatchback is the best i find as thats what ive got
an if you have got a fair sized car then yes build it as it would be great
chrisb

[Dan]

Hi Chris,


I've got a estate so a bit of room to play with. I could just about fit it in as one model but having it in two halves will make it so much easier to handle. I keep reading through your tiger thread because the way I build it will probably be very similar to your tiger build and you've included alot of information and techniques that will undoubtedly be very helpful to me.


 

[frogman3]

Hi Chris,


I've got a estate so a bit of room to play with. I could just about fit it in as one model but having it in two halves will make it so much easier to handle. I keep reading through your tiger thread because the way I build it will probably be very similar to your tiger build and you've included alot of information and techniques that will undoubtedly be very helpful to me.

WELL im pleased to have helped you Dan an yes go for it as she looks a very nice ship an in this size you can fit loads of working features
chrisb