Model Boat Mayhem - Forum

Please login or register.

Login with username, password and session length.
Pages: [1]   Go Down

Author Topic: Getting Started...  (Read 3712 times)

adam_goodin

  • Guest
Getting Started...
« on: June 30, 2011, 05:13:17 PM »

Hi All,

 After debating for quite some time now, i've decided that I'd like to try my hand at this world of submarines!!

Although i've built models of many types and variations in several different hobby groups (Tugs, Warships, 1/14th Trucks etc) ... Im totally new to Submarine modelling.

So, if i were to attain the OTW HMS Upholder Kit (oddly enough to go with my current tug build!! %%)... where on earth do I go from there? Suppliers, radio gear etc etc etc

 Any advice would be much appreciated, thanks all.
Logged

Subculture

  • Full Mayhemer
  • *****
  • Offline Offline
  • Posts: 3,856
  • Location: North London
    • Dive-in to Model submarines
Re: Getting Started...
« Reply #1 on: June 30, 2011, 06:58:07 PM »

The Upholder is a nice boat. For a first sub, it could prove a challenge, as you will need to sort out a dive system. How about cutting your teeth on an MMB Sub Sonic. Nice small, inexpensive boat, a dynamic diver, so no worries about a ballast system and it looks lots of fun. It will teach you a lot about balancing a sub, dealing with shaft and cylinder seals etc.

Regarding internals for the Upholder you can go DIY, but if that seems a bit too demanding, OTW do a module for this boat. Other possibilities include Sheerline- their Akula or Trafalgar module may work well in this boat. Also Caswell do a 3.5" Sub Driver which should work in slightly larger models like this. There is another company called A1 Downunder models who were making acrylic dive modules to bespoke requirements using a water pump system, unfortunately I don't have any more information on them.

R/C systems, you will need a minimum of four channels, however I would recommend at least a six channel system, and it has to be either 40mhz, or if you can find an old set- 27mhz FM or AM (FM is better). 2.4ghz is useless for subs, as the signal cannot penetrate through the water.

adam_goodin

  • Guest
Re: Getting Started...
« Reply #2 on: June 30, 2011, 08:39:31 PM »

Very much appreciate the response there.

 Reason I mention the Upholder is i've pretty much got my heart set on it, and already set the ball rolling so to speak. However, im prepared to put in the hard work required to build the model, im just a novice at Submarine models, having only built "surface ships" etc.

 Radio gear is not a problem, got a 40MHz 6 channel set raring to go into a model!

Is there any folks up my way that would be willing to meet for a bit of a chat and to show me their model/s?? Would again be much appreciated.

W/regards to a shaft, shaft seals and prop etc, where would i attain these from? and in these 'modules' do they have motors or is that a seperate subject?
Logged

Subculture

  • Full Mayhemer
  • *****
  • Offline Offline
  • Posts: 3,856
  • Location: North London
    • Dive-in to Model submarines
Re: Getting Started...
« Reply #3 on: June 30, 2011, 09:33:01 PM »

Enthusiasm is good, that will help you stay the course. Subs are very different beasts to skimmers, I think they have more in common with aeroplanes than aquatic craft.

There are various places you can obtain seals and other parts from. With model subs, if you speak to ten different people, you'll often come away with ten different answers. I understand that this can be very confusing, especially as most model submariners seem to talk double dutch to the uninitiated. But the first thing you need to decide really, is what ballast system you want to go for. Water pump ballast system, compressed air, gas, piston tank etc.

This is very much a personal choice, and is dictated largely by the tools and equipment available to you, preference or the size of your wallet!

This site is excellent for pointing out the pros and cons of various systems- http://www.heiszwolf.com/subs/tech/tech01.html

You could of course set the boat up as a simple dynamic diver. Not particularly scale, as you would need to ballast the boat low in the water to get it to dive at a reasonable speed, but it's nice and simple and inexpensive.

All the modules I mentioned come with motors, some are geared, others direct drive. The Upholder prop is rather large, so a geared motor is most likely going to be required. The OTW module would be custom designed for that boat, so should come with the right motor. Other modules may need some adapting.

Do you have a lathe?

Chris Behan (posts on here as Sub Driver) is not a million miles away from you. I believe he attends the Birchwood show, if you're going to that. There are also the Edinburgh and Barrow sub days coming up (July and September respectively).

I'm also organising a late afternoon/evening Dive-in at St Albans in August, which may be a bit too far South for you, but there will be quite a few boats there, and many of us are happy to hand the controls over to newcomers.

Andy

ajg141

  • Full Mayhemer
  • *****
  • Offline Offline
  • Posts: 90
  • Location: Edinburgh
Re: Getting Started...
« Reply #4 on: June 30, 2011, 11:20:00 PM »

I can confirm that the Sheerline Trafalgar module does fit the Upholder and works well. Mine is running with the lead acid battery running in the wet as per myTrafalgar before that was modified to run on a Nimh. It will be at Edinburgh on 24th July and with any luck I might find time to get her in the water this year! Good luck with your project.

Andrew

Logged

Mankster

  • Full Mayhemer
  • *****
  • Offline Offline
  • Posts: 770
  • Wheelerdealer
  • Location: London, UK
    • RC Model Submarines
Re: Getting Started...
« Reply #5 on: June 30, 2011, 11:37:14 PM »

Did you ever get your Typhoon going Andrew? Lovely Upholder by the way.

Yes agreed, first step is to decide what dive system you want to go with, next decide if you want to build your own or buy a ready made unit. Seals and whatever else you may need in terms of material and electronics will stem from that decision. There are a few sub events coming up, Edinburgh normally has quite a few subs if its not too far from you. Otherwise the next one is at a pool in St Albans so you can see what the sub is doing once under water and how it responds to the controls. Welcome aboard, you have joined an small and exclusive club  :-)

adam_goodin

  • Guest
Re: Getting Started...
« Reply #6 on: June 30, 2011, 11:45:54 PM »

Thanks Guys,

Andy - I dont have a lathe anymore (fortunately however, being an engineer, i use lathes often so Im experienced with them! {-))
 
All sounds rather exciting, so which ballast system would be better for myself and the Upholder? Or is this just personal choice?

St. Alban's is a fair drive for me, however i may be tempted if i can manage it.

Thanks Andrew - How much would the sheerline Trafalgar module set me back as it doesn't seem to state so on their site?


 I can probably do some meets from now until end August ... September Im back at Sea for around 4 weeks.

And thanks Mankster - Im happy to have joined in on the world of Sun dodger modelling (sorry, i'm a skimmer by trade! haha)

I don't particularly want to build my own units as yet so would prefer a ready made unit. It's just deciding on the best option!

All the advice is greatly appreciated!  :}
Logged

Davy1

  • Guest
Re: Getting Started...
« Reply #7 on: July 01, 2011, 08:20:53 AM »

Hi Adam,

Some very good advice on this thread , I would say and the MMB Subsonic would be a good choice for a first sub, in my opinion. I saw it running at Alfold (See  a video on the Alfold thread here.) My fellow hobbyists have had some worries about build quality but you get a very good little sub for not much money.

Regarding dive systems have a look at the AMS website which takes you through them (http://associationofmodelsubmariners.com/ and don't forget  the forum on http://www.theassociationofmodelsubmariners.com/)

For major sub events the Edinburgh model sub day (Courtesy of Edinburgh MBC) is the next up and not TOO far from you. (I will be there this year.) Then Birchwood (Warrington) (I will be on the AMS stand) and then the sub day at my home club Barrow (Which I organise.) So I hope to see you at one (or all three!)

A lathe is very useful for submarines and need not be very large or expensive .You will see my setup turning a 100mm diameter WTC end cap here: http://www.theassociationofmodelsubmariners.com/t139-u-upvc-class.

Welcome to a great hobby and I hope to see you soon,

David Forrest



Logged

Marks Model Bits

  • No Mustang Mark
  • Full Mayhemer
  • *****
  • Offline Offline
  • Posts: 889
  • http://marksmodelbits.com/
    • Marks Model Bits
Re: Getting Started...
« Reply #8 on: July 01, 2011, 08:43:40 AM »

Quote
My fellow hobbyists have had some worries about build quality


I think this comment is a bit unfair David, what you should have said was "nit picking from rivet counters who didn't/couldn't/wouldn't understand what we are trying to achieve with the Sub-Sonic kit"

I think that is a bit closer to the truth....
Logged
I HAVE NOT FAILED, I HAVE FOUND 1000 WAYS THAT DON'T WORK.!!!!

http://marksmodelbits.com/

Davy1

  • Guest
Re: Getting Started...
« Reply #9 on: July 01, 2011, 08:52:52 AM »

Hi Mark,

Yes, you may be right there. People sometimes expect everything!

My view remains that it is a very good, fun submarine for not much money.

(Congratulations also on your rapid and responsive customer service!)

See you at Birchwood (Warrington)

David

PS The Subsonic also shows her stuff on the video in the ORP Dzik thread.
Logged

Subculture

  • Full Mayhemer
  • *****
  • Offline Offline
  • Posts: 3,856
  • Location: North London
    • Dive-in to Model submarines
Re: Getting Started...
« Reply #10 on: July 01, 2011, 09:30:04 AM »

I don't know the current price of a Trafalgar module. Chris Cloke (Mr Sheerline) sells complete kits, and doesn't advertise the price of a separate module. However if you get in touch with Chris, I'm sure he'll be happy to talk business with you.

I was remiss in failing to mention that Ron Perrot is also building modules, these are based on twin piston tanks, fore and aft, and judging by the performance of his Alfa class and a friends Engel Typhoon equipped with two of these modules, they work exceedingly well.

As you come from an engineering background however, making a watertight cylinder will be a simpler task than for some, especially if you can access a lathe. Things that can befuddle a newcomer, like understanding o-ring sizing, tolerances etc. should be second nature assuming you have a mechanical engineering background.

A cylinder can be built from a variety of materials. Most people use either PVC, acrylic(PMMA), or lexan/polycarbonate. The latter two offer the possibility of a transparent enclosure, which looks very pretty and makes it a bit easier to spot leaks- sods law dicatates however that your boat will spring a leak once the top of the hull is placed on 

Acrylic is widely available in many diameters(try 'clear plastic supplies' on ebay), it's much more brittle than the other two plastics, but is more rigid and easier to polish if it gets scuffed- OTW modules are constructed from acrylic. PVC can be purchased from builders merchants, or available for a five fingered discount in a nearby skip. The range of sizes available is a little more limited than acrylic, and although unfilled PVC is transparent, most PVC pipe is filled and opaque, it also quite a dense plastic, so a cylinder built with this will be a little heavier than one in acrylic. It is as tough as old boots, PVC can be dropped and manhandled, and will take much more abuse than acrylic, but it is softer so much easier to deform. Finally lexan/polycarbonate offers the advantage of a clear cylinder, and tougher still than PVC (it's used to make riot shields). Unfortunately it has the disadvantage of being far more expensive than acrylic and PVC, and rather difficult to source in the UK. However the afore mentioned clear plastic supplies have told me they can get it to order. It is cheaper and easier to purchase in flat sheet form, and I would recommend it for making endcaps. Being softer than acylic, Lexan scuffs easier and doesn't polish up so well. It's used extensively in the States, where it's cheaper and easier to purchase.

Other materials suitable are GRP tubing, thin walled metal tubing(run an external aerial) and even wood adequately sealed.

To seal a cylinder, o-rings are most popular, fitted to the end caps. Usually nitrile o-rings are used, but you also use silicone (more squishy), Viton or EPDM- the latter two are usually a bit harder than nitrile, and much more expensive, they should last an eternity though.

They can seal axially against the face of the tubing, or radially against the inside of the tubing. Either method works well if correctly executed; with the latter method you do need to ensure that the finish of the tubing is sufficiently accurate to effect a reliable seal- a lot of plastic tubing is very variable in this respect, so it's worthwhile inspecting the tubing carefully. If the tubing is wavy, you can skim out a bit of the tubing using a mandrel on a lathe, or turn an insert to fit inside the tubing from plastic or aluminium; depending on how you do this, it can reduce access to the full internal diameter of the cylinder. With axial compression you can machine the fit for the o-ring, or even get a decent surface by hand finishing. The disadvantage with this method, and it is very slight, is that you need retaining rods running inside or outside the cylinder to tension up the endcaps.

To seal the control rods and motor shaft you can also use o-rings, however some people prefer to use rubber bellows (Robbe make some nice bellows) for the control rods, and a thing called a simmerring for the motor shaft.

Okay, so what the heck is a simmerring you ask? It's Freudenberg/Simrits trade name for an oil seal. They make them in very small sizes- down to 3mm, and they're moulded in nitrile rubber. For the upholder a 4mm shaft seal would be appropriate. They are fitted with a small radial spring, so they can withstand internal pressure upto about 4-5psi, this is important if you're using a system that pressurises the dive chamber, e.g. Piston tanks. You can purchase these from Norbert Bruggen in one off quantities-

http://www.modelluboot.de

Norbert also does lots of other goodies to help you build you own dive module, as well as some very interesting kits.

Simmerings in larger quantites are available from BSL Brammer (google that for your local BSL distributer). If you don't want to use a simmerring, you can use an o-ring with glanded fitting that allows you to compress the o-ring axially, to help it seal around the shaft (does that make sense?). This is a bit higher in friction than a simmerring, but o-rings are easier to source, cheaper to buy and easier to replace. Shaft speeds don't tend to be that high in subs, so the efficency penalty isn't as great as you might think.

Silicone o-rings have been popular for this type of shaft seal.

Finally I'd recommend you get this book-

http://shop.traplet.com/product.aspx?c=294

Not an easy read for a beginner, and not the last word in every aspect, but if you adhere to most of what is printed in that book, you should end up with a well performing boat. Ignore the electronics chapter, it's now very dated (this book was first published over 15 years ago), but everything else applies as the physics of getting a model submarine under the water haven't changed, they have merely been refined.

adam_goodin

  • Guest
Re: Getting Started...
« Reply #11 on: July 01, 2011, 12:29:00 PM »

Thanks Andy!...

 Couldn't have asked for a better response! Very close saying Mechanical Engineer, im actually a Marine Engineer so a lot of this does make sense, and has answered a lot of questions that I had lined up for you Guys.

 So module construction doesn't seem half as daunting now to me. Seems to be plenty of suppliers and plenty of options for personal choice of construction which is just what is needed.
I'll be doing some research over the next few weeks or so on ready built modules and a self built module, so no doubt i'll be asking more questions either way!

Looks like i'll need to get a lathe back in my work area at home!


Thanks Mark and Davy too for your advice and comments, all taken on-board and Im certainly looking forward to meeting some new folks and getting along to some cracking meets, seems i've been missing out all this time just buiding surface ships!!

Can't thank you guys enough for the advice, so maybe i'll get the beers in when I get along to some meets (or the Tea/coffee's)!!

Can't type much as im working, but i'll probably have some questions about some of the info. you have given me if you don't mind?

Thanks again guys.
Logged

andyn

  • Guest
Re: Getting Started...
« Reply #12 on: July 01, 2011, 01:10:26 PM »

Don't necessarily need a lathe, send me a pm with whatever you need and I'll make it for you :-)
Logged

adam_goodin

  • Guest
Re: Getting Started...
« Reply #13 on: July 02, 2011, 12:19:35 PM »

Thats very kind of you andyn! Not sure what i need yet, but as soon as i get this new Sub, i can start making decisions and knowing what i need.

Thanks very much.  :D
Logged

adam_goodin

  • Guest
Re: Getting Started...
« Reply #14 on: July 03, 2011, 01:13:40 PM »

...just had a quick look at that Subsonic ... they go like a rocket don't they!

 On the website, looking at the product, it looks great for beginners ... unlike me who's jumping in at the deep end as usual!  %)

May have to invest in one though as they look like fun and a good into. to Sub's in general.

 Also, ordered the Traplet 'Submarine Technology' Book.
Logged

andyn

  • Guest
Re: Getting Started...
« Reply #15 on: July 03, 2011, 01:15:46 PM »

...just had a quick look at that Subsonic ... they go like a rocket don't they!

 On the website, looking at the product, it looks great for beginners ... unlike me who's jumping in at the deep end as usual!  %)

May have to invest in one though as they look like fun and a good into. to Sub's in general.


Nice to see another person who gets the point of exactly what we designed it for :-)
Logged

adam_goodin

  • Guest
Re: Getting Started...
« Reply #16 on: July 06, 2011, 12:59:31 PM »

Question/s, while im waiting on books, plans, bits etc etc ....

 Construction wise as a model (not taking into account Dive module etc), what would you say the average build sequence and time is on a Sub like HMS Upholder ? Out of curiosity.

Also, w/regards to sealing a sub... this one comes in 2 halves, so for want of a better way of asking... how do the halves go together?

 Finally, for now atleast! ... Painting, what, why, when, where, how?  %) {-)

 Thanks Guys ... from a pain in the backside (an appreciative pain...)
Logged

Subculture

  • Full Mayhemer
  • *****
  • Offline Offline
  • Posts: 3,856
  • Location: North London
    • Dive-in to Model submarines
Re: Getting Started...
« Reply #17 on: July 06, 2011, 05:41:10 PM »

The fit and finish of OTW moulding is excellent. You should peg the top and bottom halves to prevent them moving over time, polyester GRP is a little more prone to this than epoxy, but I find even epoxy will move, especially if you leave it in the sun on a hot day. I use zip ties for securing unstarted mouldings in storage.

Build time depends on your expertise and how many hours you put in each day. The upholder will be a much easier build than say a u-boat, with all the fiddly detail.

Andy

adam_goodin

  • Guest
Re: Getting Started...
« Reply #18 on: July 10, 2011, 11:36:23 PM »

Cheers Andy.


Well, i've received my Sub. Technology book...and more importantly... HMS Upholder !! Very pleased (thanks Peter) with it and I can't wait to get cracking with it. I will, as some have mentioned, be pegging to prevent distortion of the 2 moulds, and then i'll steadily progress through, taking an account of Photo's etc to post up.  :-))
Logged
Pages: [1]   Go Up