Topic: British S Class (Read 66539 times)

gingyer · « **Reply #150 on:** November 28, 2012, 09:37:34 pm »

thanks Adam,
I am sure we all wish you good luck and keep your head up mate
and your friends are here when you need a bit of sanity

Colin

16-21 · « **Reply #151 on:** November 28, 2012, 09:48:43 pm »

Cheers big yin!!!

She's packaged up and just putting postal address on.

take it easy man dont work to hard lol

TomP · « **Reply #152 on:** December 04, 2012, 08:49:32 pm »

Hi all, no worries Adam it's been a long time since I have touched either of my subs. I have been working abroad and got back yesterday so hopefully now I can start back on them will keep you posted. Cheers Tom

Pondweed · « **Reply #153 on:** December 21, 2012, 07:37:12 pm »

If you're building an S Class, I'd have thought the book 'One of our submarines' would have been essential reading! It won't help you build the model but it'll give you much needed guidence on avoiding Japanese A/S vessels.

Seriously, it's not only interesting, I found it a really decent read. The photos of Storm will also help.

Secondly, on a more practical note: to find the volume of a irregular shaped object, you need to convert it to a regular shape, in this case a cylinder, and take it from there. So you'd divide the length up ... say every inch... and measure the perimiter at these marks with a piece of string.

You then average these measurements which gives you the average circumference. Divide it by Pi [3.142] and you have the radius? (is that right? Long time since I left organised education)

It's then a simple Pi times the radius squared which gives you the area of the object, you then times the area by the height to get the volume.

Have I got this right? It'll give you the ball park figure.

Subculture · « **Reply #154 on:** December 21, 2012, 08:33:48 pm »

If you divide a circumference by pi, you get the diameter, not the radius. The rest of the formula was correct.

The only reliable method of obtaining the correct ballast tank volume for your sub is to use the test tank empirical method which has been documented many times both on this forum and elsewhere. Calculation will get you a rough idea, but there is a huge fudge factor, so I would only use it for getting an idea on overall tank dimensions and to help decide on things like pump size in relation to dive times etc.

If you try to use weight with a freeflooding hull made from GRP and brass media, which the OTW s-class does, you will most certainly end up with a tank that is too large. On the flip side if you make a sub from wood (don't laugh plenty of wooden subs out there), you'll end up with a tank that's too small.

The empirical test tank method is very straightforward, requiring no mathmatics and is extremely accurate.

Pondweed · « **Reply #155 on:** December 22, 2012, 06:18:16 pm »

Quote from: Subculture on December 21, 2012, 08:33:48 pm

If you divide a circumference by pi, you get the diameter, not the radius. The rest of the formula was correct.

Good to know the Councils money wasn't wasted.

TomP · « **Reply #156 on:** January 02, 2013, 08:24:19 pm »

Right! Need to get on and have this ready for the summer. I'm just finishing it off filling and sanding and adding a few detail parts before I start painting. I'm probably fussing to much but does anyone have an idea on how to make the edges on the casing rounded. I've tried using a sanding block but keeps going wrong and I get wobbly curves down the length of the casing. Any help will be much appreciated cheers Tom

Subculture · « **Reply #157 on:** January 02, 2013, 09:06:19 pm »

Make a scree tool. How do you do that you ask?

Well get some metal sheet, any will do aluminium or brass tend to be easier to work, but use what you have. Needs to be about 1mm thick or so. mark out the shape of the radius you want on the metal, so you have a template in reverse. Apply filler to the model, and move the scree tool along the boat. Clean the tool after each pass.

By doing this you get the shape pretty much bang on from the start. You'll probably need a couple of coats of filler, as it will shrink a bit as it cures.

You can also make a custom sanding block. Use some soft balsa wood or pink/blue foam. Trim it to the shape of the radius, and glue on some abrasive paper. Then you can use that to lightly sand back any imperfections.

TomP · « **Reply #158 on:** January 03, 2013, 11:51:41 am »

Thanks Andy I shall give that a go. Cheers Tom

TomP · « **Reply #159 on:** January 28, 2013, 03:22:44 pm »

Following the crap weather I have moved the sub indoors to get some work done. Wife has gone away for the week and I'm off work so I hope to complete the build and will just have the module to go.

TomP · « **Reply #160 on:** February 26, 2013, 02:13:54 pm »

WTC arrived today from A1 downunder subs, very well packed for postage and very pleased with the WTC need to get on and install the electronics now!

gingyer · « **Reply #161 on:** February 26, 2013, 02:54:44 pm »

Hi Tomp
that looks good,
like you i need to get into mine I started the Conning Tower but then somebody has forced me to work
for a living

TomP · « **Reply #162 on:** February 26, 2013, 10:03:32 pm »

Torpedo tubes made, need to fit the doors etc but will make this all removable so can work on it later and possibly launch torpedoes.

TomP · « **Reply #163 on:** February 27, 2013, 08:30:08 pm »

New WTC in the boat can't wait to get it all working must get on!

spooksgone · « **Reply #164 on:** June 18, 2013, 08:56:11 am »

Are you still there Tomp? Whats the latest with the S class? I'm dying to know!
Cheers
Phil

TomP · « **Reply #165 on:** June 19, 2013, 08:28:41 am »

Hi Phil, yeah it's been a long time. I'm still working on it when I get chance really annoying as its so close to being ready for painting. Work has been taking most of my time with being away from home etc. I will finish it just taking a long time, how are your projects coming along? Tom

spooksgone · « **Reply #166 on:** June 19, 2013, 08:52:31 am »

Hi Tomp. I have been busy decorating the whole house, not touched any thing really. I have got my next project though. I am going to do a model of HMS Woodpecker, based on the fleetscale hull of HMS Starling, and the Sirmar fittings, I should have all the bits and pieces with in a couple of months. Glad your ok. Looking forward to seeing your S class.
Cheers Tomp.
Phil

TomP · « **Reply #167 on:** July 25, 2013, 07:05:30 pm »

Got my grubby little hands on these

It's an OTW O Class wasn't really after that just the module, chamber not quite big enough for S class but can make one easily so now need to finish the S and XXI and have modules ready for both. Will have a think about selling or keeping O class

Subculture · « **Reply #168 on:** July 25, 2013, 08:28:11 pm »

Don't forget you should be able to fill the OTW modules tank to a higher percentage than the A1 module, owing to the formers venting into the dry spaces.

Can I ask why you have decided not to use the A1 module?

TomP · « **Reply #169 on:** July 25, 2013, 10:57:15 pm »

The OTW is 2.04 litres in volume the A1 is 1.9 litres, the A1 tube I can't fit the Shurflo pump in that I was kindly given by Spooksgone as its 100mm not 110mm like the OTW. The Shurflo pump will only fill the tube to half way. I have a Kavan pump that will fill it to 3/4 full. I can make the A1 module vented like the OTW I have some sensors I can use to control the pump. I got the OTW module for less than quater of a new one so couldn't say no really so wanted to try both see what works best for me and which is the most stable. Also I have the O class that I might build so the OTW module would fit in that and I also have a 1/32 scale E class sub and have been told that the OTW module would also fit that. I have no idea what I will need for the XXI yet might be lucky and it would fit that too

gingyer · « **Reply #170 on:** July 25, 2013, 11:57:52 pm »

Los like,you got a big bargain there

When you say the OTW tank is 2.04litres
I take it that is the tank size required for the S class

Subculture · « **Reply #171 on:** July 29, 2013, 08:11:44 pm »

Six of one, half dozen of the other.

I think you will find the modules fairly evenly matched in terms of performance. The Shurflo pump isn't designed for a high pressure system like a sealed tank, you're much better off with the Kavan pump and pinch or solenoid valve to stop the back flow.

Rob47 · « **Reply #172 on:** August 12, 2013, 10:04:58 pm »

Interesting reading especially when I saw Stan Robinsons name appear, he was one of the founding members of the Gloucester and District Model Boat Club, had the Gato boat, + his destroyer that dispensed detonators which managed to kill the fish in the pond.
I am now back to building currently 1/96 re work of my HMS Tiger so probably will re join once it is finished.

TomP · « **Reply #173 on:** July 11, 2016, 10:20:08 pm »

Wow long time since I put anything about this! Well I was so close to painting but there was so many little niggling issues that I decided to attack a few of them. Firstly the WTC biggest reason why I haven’t got too far for so long so bit the bullet and bought a OTW module for this, 8 week delivery so thought now’s the time to get on with it. Secondly over time the filler I have used has cracked and looks a mess so dug it all out and starting again. Flood holes I had made out of plasticard over time has become quite brittle so back to the drawing board with that one hopefully will have a detailed etch ready soon for this. Then details after a lot of research have some good pictures to help improve it. I wanted a set of John Lambert plans but sad to hear he has passed away and they are not available at the moment.

Subculture · « **Reply #174 on:** July 12, 2016, 09:50:22 am »

If you've had problems with the filler cracking away, that indicates movement in the substrate.

I would consider a shift in strategy. Either build up the bulk of the filling with glass fibre and resin, then just a skim of polyester putty, or use a stronger filler, like an epoxy based filler. This will be a bit harder to sand and takes overnight to dry, but it is much stronger than polyester putty.

A good epoxy putty that spreads well is Reactive resins easy fair. Note that although this is the easiest to work epoxy filler I have encountered, polyester filler is still a little easier, and I often use a bit of polyester putty over the epoxy as a stopper to fill in the odd bit or two.

http://www.reactiveresins.com/easy-fair-t-s.html

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Author Topic: British S Class (Read 66539 times)