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[Lash151]

Thanks... I had seen the Revell kits, but not these... They look good for £25!  The Revell 1/72 kits also look good and are a good size, but are quite a lot more money...
I shall consider all my options!!!
Lee

[Patrick Henry]

I presume you mean the Gato and the Type V11 U-boat, Lee...not only more expensive to buy, but also having twin propshafts, props and rudders, more expensive to fit out. And all that scale detail...periscopes to knock off, etc.

The SeaWolf needs only a single propshaft and prop and a single motor, there's very little detail to knock off, which makes life a lot easier.


Rich

[redboat219]

Virginia class submarine made from sewer pipe:

http://www.youtube.com/watch?v=0wBa7w7-DZs&feature=youtube_gdata_player

[Lash151]

Thanks for that link... apart from the shiny paint, it looks pretty good... certainly goes well.
Lee

[Subculture]

I rather liked Circlips idea of a radio controlled torpedo. I've seen large working torpedoes, but they're controlled by speed only- no control over pitch or steering. Even WWII designs were capable of speeds in excess of 40 knots, and an 11cm pipe would give you a torpedo at around 1/5th scale with a scale speed of about 20 knots.

Getting it to run well at that sort of speed would present some challenges to the builder, but you could opt to model a slower torpedo, however even the sluggish versions were no slouch, capable of 20-30knots, so you have every excuse to run it fast. Just don't expect it to win any steering competitions!

[Circlip]

Only referred to torpedo as having no front planes for depthing and it having tail feathers only for guidance. Must try and dig out the Hydro type units, they used clear plastic tubes and the gimbel mounts looked like a universal Kort tube.

  Regards  Ian.

[Subculture]

I'm pretty sure that was an article by Nick Burge from the early to mid-nineties. There were two boats, one big, one small, the big one had a gimballed kort, and the other had a more conventional layout.

[Patrick Henry]

My torpedo hull...four foot in length, all alloy, and based upon the early Whitehead model.







Rich

[Lash151]

Blimey... is that going to be a working model? 
Lee

[Patrick Henry]

Well, it was going to be, Lee...it's sat in my hall cupboard ever since I got it, I'll never build it now.



Rich

[Subculture]

What version of torpedo was that? All of the pictures of Whitehead torpedoes I've seen were more curvy than that, like in this picture-

[Patrick Henry]

What version of torpedo was that? All of the pictures of Whitehead torpedoes I've seen were more curvy than that, like in this picture-

"My torpedo hull...four foot in length, all alloy, and based upon the early Whitehead model."

Note the word 'based'...

[Davy1]

Hi Lee,

Sorry about the late reply.

Richard is right to mention modifying plastic kits - a good route in - of which I know little!

If you want to get into fibreglass, then making bow and stern cones for a PVC tube is a a good way to start.

Make a male former - turned from wood or foam on a lathe (if you have access to one?!)Then cast  a female from fibreglass and then you can make as many as you want.

PM me your email address if you would like me to send you an article on making the Russian "Charlie" Class (Liked Redboats video by the way.)

David

[Subculture]

If the hull is symmetrical, you could make half a plug and mould, cast two halves off, trim them back, flip them around and then join them together. A lathe will make producing round stuff easier, but you can easily get by without one, especially for this kind of work. The other technique quite a few modellers use is the lost foam method, where you glass straight over a sacrificial foam master, and once cured, melt out the foam. The downside is you only get one shot at this, so if you make a mess of it, you have to start over, and you only get one set of parts.  I prefer making a set of moulds, although it does double the work.

I know a lot of modellers don't like glassfibre work. I've used plaster moulds in the past for simple shapes. I don't use ordinary plaster, but a special tooling plaster, which you can get from Tiranti's. This stuff set's rock hard in minutes, so you have to work very quickly with it. The finished tools are extremely tough.

You can use epoxy resin, which is close to odourless, and I have found you get a much longer pot life, which gives plenty of time to get the laminate just right. It does cost quite a bit more than polyester resin, but the finished laminates are very strong, and for small quantities the cost will still be small.

The other option is some stuff supplied by a company called 'Smooth-on'. It's called 'Shell-shock' and it's a brushable thixotropic polyurethane resin, with the consistency of gelcoat. This is strong enough to be used without reinforcement, so you just paint two or three coats it into a prepped mould, allow to cure for an hour, and it's ready to be demoulded. It is a bit pricey, but I've found Smooth-on products work really well-

http://www.smooth-on.com/Urethane-Plastic-a/c5_1120_1165/index.html

[Davy1]

I wouldn't recommend the lost foam process. That was the first mistake I made when I built both the "Charlie" and my R class.
You need to do a very large amount of shaping and sanding and resin is hard! (Nigel Edmonds (Mr Fibreglass!) thought  I was "misguided" when I described doing it this way!)

And you will usually end up making a female mould anyway, if you like the model, so better to make an easily formed male followed by a female straight away.

David

[Lash151]

Thanks for all the advice guys... I like the plastic kit route but at the same time I have found myself eyeing up bits of pipe wherever I go, so not sure yet!!  I might head in both directions at the same time and see what happens!!  I do like the scrap and found objects route... last night I found myself in Tesco measuring pudding bowls to see if they would make good nose cones!! The kit is appealing too for precisely the opposite reason! lol
Lee

[Circlip]

With a bit of careful Hacking, you could cut longitudinal sections out of a piece of pipe like darts and with application of heat from a paint stripper type hot air gun you could "Mold" a nose or tail section over a pattern. Beauty about waste system pipes is that they can be solvent welded if ABS or PVC. Beware of Polythene type pipes. You need to "Hot plate weld" those.

  Regards  Ian.

[Davy1]

Hi Ian,

Great minds think alike?!

http://www.theassociationofmodelsubmariners.com/t139-u-upvc-class

It works quite well and she is still holding together!

David

[Lash151]

Hi... yes thats a good way of doing it... Strangely, I got to thinking about this because I was considering building the whole boat out of wood using the plank on frame method. I just received a copy of the Marine Modelling Submarine Special and in there is an article on a build of a U-202 done almost entirely as plank on frame (with some excellent brass work as well). The plank on frame method didn't seem to meet with much enthusiasm in another thread I posted... I thought perhaps I was being daft by contemplating this method but apparently it is feasible.... but does no one like the idea of using wood?
Lee

[Subculture]

I think you received some pretty objective answers on the pros and cons of using wood. If it's a material you feel most comfortable working with then by all means use it, just remember to seal it well to prevent moisture ingress.

Most model submariners use plastics, composites and metal for construction, because they are inherently moisture proof. The thing to do now is choose a design, and then decide how you want to construct it.

[Patrick Henry]

Personally, I don't like wood and it doesn't like me. I can't even draw a straight line on the stuff, let alone cut one, but it does have it's uses. U-117 was 99% timber built, then coated in resin to waterproof it inside and out, then painted and finally varnished...it never let water in where it wasn't supposed to.

It does make a boat extremely bouyant however...with a boat 108" long, than means a very heavy boat. U-117 weighed 3 hundredweight (whatever that is in these new fangled metric measurements) ready to submerge, it took three strong men to get it in the water and five even stronger men to lift the thing out when she was full of water. I was cursed at shows and exhibitions when I arrived with her in the car....most of the guys would disappear rather quickly when it was time to move the thing!

But, she proved that wood can be used to make a model submarine, and she proved it well. If you can work with wood, then by all means work with it, just remember to keep the word 'waterproofing' at the forefront of your mind as you progress through the building.


Rich

[Lash151]

Well, the design I like the most is the Akula ... and the preferred method of construction is erring towards the 110mm PVC pipe with shaped wooden ends and sail, sealed with resin...
This is what I keep coming back to in my head.... !  110mm beam makes it about 1/90th scale... about 950mm long.  
Lee

[Lash151]

Yes, I really like working with wood... I used to make furniture when I first moved to Norfolk... so its kinda natural to build stuff with wood, but you're right its not the most waterproof material ever!  The lost foam technique is interesting though... I used to cast metal parts and I would carve the pieces from hard wax. (which Tiranti sell in large blocks) You make a silicone mould from it..Then you pour metal in one end and the wax pours out the exit hole, leaving the space filled with metal.
Lee

[Davy1]

Yes, I like wood too.

But in submarines - chocolate and teapots come to mind!

David

[Lash151]

Thats a point... you could carve the nose and tail from chocolate!! (The lost Chocolate technique)