Model Boat Mayhem

Please login or register.

Login with username, password and session length.
Pages: [1] 2 3 4 5 6 7 8 9 10 11   Go Down

Author Topic: Salt Water Darnell U37  (Read 54914 times)

unbuiltnautilus

  • Portsmouth Model Boat Display Team
  • Full Mayhemer
  • *****
  • Offline Offline
  • Posts: 3,080
  • Location: Portsmouth, England, third rock from the Sun....
Salt Water Darnell U37
« on: May 10, 2011, 07:22:53 pm »

Having had a long list of owners before me ( including me four years ago!) I have become the proud owner of a Darnell type VII u-boat, It has only been underwater once, when it sank!
I have had a large amount of helpful advice on the internals of the model from fellow forum members, for which I would like to say a hearty Thank You :-))
Now its time to look at my rebuild and see what you think so far?

The model had been weathered by a fellow member and camoflaged to boot! I liked the scheme but felt the camoflage was rather lost in the weathering. Then the red antifouling became an issue ( latest thinking seems to indicate red antifouling was seldom if ever used.) repaint time!
Logged
Listen politely, nod approvingly, then do what you want, works for me!

unbuiltnautilus

  • Portsmouth Model Boat Display Team
  • Full Mayhemer
  • *****
  • Offline Offline
  • Posts: 3,080
  • Location: Portsmouth, England, third rock from the Sun....
Re: Salt Water Darnell U37
« Reply #1 on: May 10, 2011, 07:35:38 pm »

The repainting of the sub started a couple of weeks ago, firstly I applied liquid masking film Maskol onto the model in random patches, this was left to dry and the camoflage colours were reclaimed with an airbrush.









The Maskol will be rubbed off of the model when the initial paint colours have been laid down, the idea being to simulate chipping of the paint, exposing layers underneath. these can then be picked out with rust effects etc at a later stage of the weathering.






The last three images show the waterline and black antifouling going on. The antifouling wont stay black for too long as this is just a base colour to weather down to a dark grey later.
The chipping can also be seen in the final photo, also the slightly' scuzzy' waterline. It does not warrant a pin sharp, showroom waterline, as it has been at sea long enough to chip this away as much as the other parts of the paint work. Did the dark grey antifouling always extend over the saddle tanks, as so far I have not depicted this? Mostly due to the less than distinct outline that the Darnell mold suffers from.
Logged
Listen politely, nod approvingly, then do what you want, works for me!

unbuiltnautilus

  • Portsmouth Model Boat Display Team
  • Full Mayhemer
  • *****
  • Offline Offline
  • Posts: 3,080
  • Location: Portsmouth, England, third rock from the Sun....
Re: Salt Water Darnell U37
« Reply #2 on: May 10, 2011, 07:47:42 pm »

The aft watertight compartment houses a couple of Pittman motors, these I am keeping, however I had to remove the beatufully done radio tray fitted by a previous owner as I needed the space.

The space issue was caused by my intention to be as mean as possible during this build, spending as little as possible and using up existing parts that I have laying around. This included enough D sized Nickel Cadmium 4400mAh batteries to make up two 4.8v packs, giving me 9.6v and little need for ballast. The model may sail with its bow sticking out the water at an extreme angle O0

I made a replacement radio board from 6mm acrylic to mount the two hydroplane and rudder servos, plus other, as yet undecided components.






As mentioned in the title, this model is intended for use in salt water which produces a number of limitations in operation, and forced my hand towards a 'closed' ballast system. The other problem I am likely to encounter is Depth Charge Attack! The model is going to be used in the Portsmouth Display Teams Convoy Action, where the water is suitable. Our convoy escorts are being encouraged to" make it look good, but dont mean it!" I assume the average model submarine 'reacts badly' to depth charges?!
Logged
Listen politely, nod approvingly, then do what you want, works for me!

andyn

  • Guest
Re: Salt Water Darnell U37
« Reply #3 on: May 10, 2011, 08:45:13 pm »

Lovely model, I'm just about to start building one and if mine turns out anywhere near as good I'll be very happy indeed :-))

Any chance of some pics of the insides in general?
Logged

unbuiltnautilus

  • Portsmouth Model Boat Display Team
  • Full Mayhemer
  • *****
  • Offline Offline
  • Posts: 3,080
  • Location: Portsmouth, England, third rock from the Sun....
Re: Salt Water Darnell U37
« Reply #4 on: May 11, 2011, 09:53:57 am »

Lovely model, I'm just about to start building one and if mine turns out anywhere near as good I'll be very happy indeed :-))

Any chance of some pics of the insides in general?



Thanks for the complements, however, at least the last two owners had more than a small part in the tidy finish of the model. If it dives AND surfaces, however, I'm taking the credit for that!
I will post more pictures as the refit goes on...
Logged
Listen politely, nod approvingly, then do what you want, works for me!

Davy1

  • Guest
Re: Salt Water Darnell U37
« Reply #5 on: May 12, 2011, 05:47:56 pm »

Looks very nice indeed!

Hope to see the display team somewhere soon!

David
Logged

Subculture

  • Full Mayhemer
  • *****
  • Offline Offline
  • Posts: 4,010
  • Location: North London
    • Dive-in to Model submarines
Re: Salt Water Darnell U37
« Reply #6 on: May 12, 2011, 06:48:51 pm »

Might want to use polycarbonate for those hatch lids instead of acrylic- bit more resistant to depth charging.

unbuiltnautilus

  • Portsmouth Model Boat Display Team
  • Full Mayhemer
  • *****
  • Offline Offline
  • Posts: 3,080
  • Location: Portsmouth, England, third rock from the Sun....
Re: Salt Water Darnell U37
« Reply #7 on: September 30, 2011, 05:21:52 pm »

Back o the horse after the summer.
First thing to sort out is the typical Darnell 'middle age spread'! The upper hatch has already had locator pins fitted, however the fit was still a bit suspect. So, I proceeded to wax polish the upper hatch flange, while burring a rough surface on the lower main hull flange. Much fibreglass repair paste applied followed by bolting the upper and lower parts together. Then smooth the gunk that oozes out of the join and wait.....
Good news, it came apart :-)



The blue/green line just below the join line is the repair paste, it sticks and it works, yay!

I am fitting two 4oz trim tanks fore and aft, these will be half filled with liquid and connected to each other via a reversible pump. My plan is to use these for fore and aft trim, possibly including a 'sinking by the bow or stern' effect. So, I shaped two brass brackets to fit the 4oz tanks as shown.









The pump will be controlled, old school, by a mechanical reversing speed control. This one is a Mardave style unit available from Hunter Systems and fixes directly to a servo and can be fitted with an appropriate resister for half speed operation. I dont think I will need any sort of failsafe function on this unit, as long as I have failsafes on throttle and main pump control.

Finally, a quick overview of progress so far..



Logged
Listen politely, nod approvingly, then do what you want, works for me!

unbuiltnautilus

  • Portsmouth Model Boat Display Team
  • Full Mayhemer
  • *****
  • Offline Offline
  • Posts: 3,080
  • Location: Portsmouth, England, third rock from the Sun....
Re: Salt Water Darnell U37
« Reply #8 on: October 07, 2011, 06:26:32 pm »

Weathering was on the cards last night, however, first some general inside shots. This model does not claim to be at the pinnacle of technology, but is being built for the rough, salt water, depth charge riddled depths of Canoe Lake in Southsea, and is my way of saying thank you to all the airbag equipped Darnell/Metcalf/Models By Design models that have gone before :-))













Stern to bow; Rudder linkage, aft trim tank, aft compartment, centre compartment and airbag, fore compartment, fore trim tank, front hydroplane linkage. Notice the green filler along the flange line added in the last post.
Logged
Listen politely, nod approvingly, then do what you want, works for me!

unbuiltnautilus

  • Portsmouth Model Boat Display Team
  • Full Mayhemer
  • *****
  • Offline Offline
  • Posts: 3,080
  • Location: Portsmouth, England, third rock from the Sun....
Re: Salt Water Darnell U37
« Reply #9 on: October 07, 2011, 06:31:38 pm »

Time to empty the compartments, evacuate the bowels, so to say!











The aft compartment houses 2x 4.8v 4400mAh D size packs, 2x servos for hydroplane and rudder control, and 2x Pittman motors for main drive. This is all removable in about two minutes at the moment. This will soon change as I hook up wiring and linkages though.
Logged
Listen politely, nod approvingly, then do what you want, works for me!

unbuiltnautilus

  • Portsmouth Model Boat Display Team
  • Full Mayhemer
  • *****
  • Offline Offline
  • Posts: 3,080
  • Location: Portsmouth, England, third rock from the Sun....
Re: Salt Water Darnell U37
« Reply #10 on: October 07, 2011, 06:37:20 pm »

Fore compartment.







This contains the main air pump, which uses a single cylinder steam engine connected to a Bueller 18v motor. This is reversable and transfers air from the radio compartment to the air bag and vice versa. The smaller pump is an MFA reversable water pump and will transfer trimming water between the fore and aft 4oz fuel tanks mounted on the brass straps. Various bits of electronic trickery are still to be shoe horned into the model.
Logged
Listen politely, nod approvingly, then do what you want, works for me!

unbuiltnautilus

  • Portsmouth Model Boat Display Team
  • Full Mayhemer
  • *****
  • Offline Offline
  • Posts: 3,080
  • Location: Portsmouth, England, third rock from the Sun....
Re: Salt Water Darnell U37
« Reply #11 on: October 07, 2011, 06:55:41 pm »

Having only recently ruined the below waterline finish with various grades of sandpaper, grit and files, it was time to remedy the mess caused! I used Blackboard paint again, this time, however, I intended to start adding the weathering. Yesterday was stage one.











I dont like Dry Brushing as an effect, I will use it but prefer not to where I can come up with an alternative. On this model I am trying to blend two colours together at once. In the tradition of 'modern' weathering techniques, we will christen it Wet Blending. ( check out any scale mag involved in either plastic kit aircraft or military modelling, weathering is now broken down into, drybrushing, pre-shading, post shading, modulation, washes, spanish technique, blah blah blah! Its all weathering and was developed by the old masters hundreds of years ago for two dimensional painting on canvas. Now hijacked in the 21st century and labelled! Rant over...)
Wet Blending is a technique developed by myself, yesterday, which involves laying down more than one colour at a time, then blending or streaking it in in the general direction of the wear and tear on the vessel or vehicle. In this case, I was mixing Blackboard Paint and two shades of Tamiya acylics on the model, as well as mixing an intermediate colour on scrap card to help blend in the effect. It must not be one uniform colour as that defeats the purpose of the effect, more a streaky effect drawn across the model from the top to the bottom. The good news is that as it dried it actually worked!
Logged
Listen politely, nod approvingly, then do what you want, works for me!

unbuiltnautilus

  • Portsmouth Model Boat Display Team
  • Full Mayhemer
  • *****
  • Offline Offline
  • Posts: 3,080
  • Location: Portsmouth, England, third rock from the Sun....
Re: Salt Water Darnell U37
« Reply #12 on: October 07, 2011, 07:06:36 pm »

On with the weathering. The problem with any weathering effect that I find is brush marks, if you can see the brush marks, you can see how it was done. loose the brush marks by blending them in with thinners or in this case by blending them in with the other colour.





In this case, the brush marks were got rid of with a sludge like mix of blackboard paint and water. This was brushed over the offending area and lightly dabbed off with a bit of tissue paper. Sometimes this needs to be done more than once to obtain a satisfactory effect.




As I had some green sludge unused, I had a go at a mucky waterline, by drawing the brush along the waterline and leaving wet, watery paint where wanted, I figured it would dry to a nice finish. Fortunately this worked, if it hadn't worked, acrylic paint is a devil to remove once it dries as solvents wont touch it. Usually I would use enamel paints for this effect but I was in a hurry and did not have any with me at the time.
Logged
Listen politely, nod approvingly, then do what you want, works for me!

unbuiltnautilus

  • Portsmouth Model Boat Display Team
  • Full Mayhemer
  • *****
  • Offline Offline
  • Posts: 3,080
  • Location: Portsmouth, England, third rock from the Sun....
Re: Salt Water Darnell U37
« Reply #13 on: October 07, 2011, 07:12:24 pm »

With the paints drying it was time for a quick overview. Generall I am happy with the effect, there are some areas where the brush marks are showing through and they offend my eye!









The next stage will involve either oil paints or enamel paints, and will be washes or airbrushing...hows that for planning ahead?
Logged
Listen politely, nod approvingly, then do what you want, works for me!

rmaddock

  • Guest
Re: Salt Water Darnell U37
« Reply #14 on: October 07, 2011, 07:24:21 pm »

I think, Sir, that your eye is easily offended.
That has to be the best painting and weathering I've seen. Utterly convincing.
Logged

sub john

  • Guest
Re: Salt Water Darnell U37
« Reply #15 on: October 07, 2011, 07:45:12 pm »

Reply#13
 HI Unbuiltnaultilus
   I would like to second that and say the weathering looks very good,how do you fancy having a go at a bigger sub. I noticed that you are  using a single cylinder steam engine for a air pump just a idea have you thought about using a blood pressure air pump they pull quite low current  about 200ma at 6v  sub looking good
   All the best John
Logged

bassplayer1

  • Guest
Re: Salt Water Darnell U37
« Reply #16 on: October 07, 2011, 11:39:16 pm »

Great job and the weathering is super!!!
Logged

unbuiltnautilus

  • Portsmouth Model Boat Display Team
  • Full Mayhemer
  • *****
  • Offline Offline
  • Posts: 3,080
  • Location: Portsmouth, England, third rock from the Sun....
Re: Salt Water Darnell U37
« Reply #17 on: October 08, 2011, 09:30:38 am »

Cheers guys, truly beauty is in the eye of the beholder, however, so are those niggling little bits that you and you alone can see. We are our own worst critics.
I have a wrist mounted blood pressure thingy which will be disassembled at some time soon, however I like the look of big bits of brass chugging about, its the Steampunk in me.
Bigger subs, there lies a story. I have a nearly complete engel Typhoon which is heavier if not longer, a Sheerline Alfa at about 84", unstarted but I am looking forward to that one, and hiding in someones garage roof is a 1/32 scale WWII Group 3 T Class sub at 104"! I feel I need to get back on the submarine horse first with an easier project, hence the Type VII.
Logged
Listen politely, nod approvingly, then do what you want, works for me!

thegrimreaper

  • Guest
Re: Salt Water Darnell U37
« Reply #18 on: October 08, 2011, 10:03:21 am »

Sheerline Alpha ???? I dont see that advertised on the sheerline webset would love to get my hands on one that big

paint job looks superb though

regards Mark
Logged

unbuiltnautilus

  • Portsmouth Model Boat Display Team
  • Full Mayhemer
  • *****
  • Offline Offline
  • Posts: 3,080
  • Location: Portsmouth, England, third rock from the Sun....
Re: Salt Water Darnell U37
« Reply #19 on: October 08, 2011, 10:30:41 am »

Give the man a ring, he had the mould along with the big Los Angeles. When I bought it the Los Angeles mould was unservicable but the Alfa just needed a dust down and minor repairs. Mind you, the fate of lots of subs has befallen it. I have had it over 3 years and not started it yet!
Logged
Listen politely, nod approvingly, then do what you want, works for me!

thegrimreaper

  • Guest
Re: Salt Water Darnell U37
« Reply #20 on: October 08, 2011, 03:14:11 pm »

I think I will send Chris an e-mail  thanks for the info

regards Mark
Logged

unbuiltnautilus

  • Portsmouth Model Boat Display Team
  • Full Mayhemer
  • *****
  • Offline Offline
  • Posts: 3,080
  • Location: Portsmouth, England, third rock from the Sun....
Re: Salt Water Darnell U37
« Reply #21 on: October 24, 2012, 04:14:28 pm »

The build is back on. Any advice on what to use in the fore and aft trim tanks as a liquid ballast. It is a closed system, transferring liquid ballast fore and aft as needed, via an MFA geared pump. I need a suitable liquid that wont rust up the pump, eat its O Rings or go stagnant and stinky over time, any ideas??
Logged
Listen politely, nod approvingly, then do what you want, works for me!

Davy1

  • Full Mayhemer
  • *****
  • Offline Offline
  • Posts: 313
  • Association of Model Submariners
  • Location: Cumbria
Re: Salt Water Darnell U37
« Reply #22 on: October 24, 2012, 05:14:43 pm »

You may not appreciate an alternative suggestion at this stage  :-)) but have you considered moving one of your large battery packs with a servo?

You would get a useful angle change with a surprisingly small movement 20mm or so. (A formula in Norbert Bruggens "Technology" book will give you an estimate.

It is also much simpler than a pumped trim system and it is also proportional.

Again apologies if you have already considered and discarded this idea.

David
Logged

unbuiltnautilus

  • Portsmouth Model Boat Display Team
  • Full Mayhemer
  • *****
  • Offline Offline
  • Posts: 3,080
  • Location: Portsmouth, England, third rock from the Sun....
Re: Salt Water Darnell U37
« Reply #23 on: October 24, 2012, 05:19:43 pm »

All ideas are appreciated, even if I cannot apply them to this project. Space is at a premium as I am divided into three small compartments with this model. I do like the idea however, and may be able to apply it to a later project, maybe an 'unbuilt' project...soon to be an 'almost started' project, soon'ish :}
Logged
Listen politely, nod approvingly, then do what you want, works for me!

Davy1

  • Full Mayhemer
  • *****
  • Offline Offline
  • Posts: 313
  • Association of Model Submariners
  • Location: Cumbria
Re: Salt Water Darnell U37
« Reply #24 on: October 24, 2012, 05:28:17 pm »

Right oh!

Coming back to your original question. I would suggest something like car antifreeze - or a water/methanol mix. Something in there to kill the bugs but still tolerant of some water leakage.

David
Logged
Pages: [1] 2 3 4 5 6 7 8 9 10 11   Go Up