Eisernwolf

Its been a while!  Since my last post, a lot of progress had been made:

1) Bow section:

Built a lip to help how down the upper bow section

To secure the upper bow section, I drilled out and installed a nut inside a styrene brace.

A bolt will pass through this fixture .

Upper bow section secured!

Bow flood holes on the hull and bow section have been drilled.

At the time the hull master was built, I did not have access to schematics that showed both the port and starboard profiles of the boat, so I assumed that they were identical.  As a result, two anchor cavities were hollowed out…  I had wanted to keep this arrangement since it made my boat look unique but ultimately decided to fill in the port side cavity for scale.  I also sanded down the lower bow section to make sure that the torpedo doors could open and close smoothly.

CA’ed a thin styrene sheet to the upper deck and sanded it down.  Some flood holes will be drilled out after priming.

2) Midships:

To prevent hull flex and to add rigidity, I built a series of hull braces that will be glued between the saddle tanks.

Here’s the above installed.

Also added a few more on the bow…

…and the stern.

The joint between the bow and stern halves was also sanded to avoid leaving a gap when both sections were assembled, I also spent a few days sanding the saddle tanks and hull to make both sides symmetric.  Had I put in more effort when the hull master was being built, I wouldn’t have had to sand off some of the styrene plating to make the contours symmetric.  Lesson learned!

3) Upper Deck:

The upper deck was cut from ABS sheets, flood holes were drilled out, and both sides were held together using styrene braces.  The ABS was heated with boiling water to make it more flexible.

Partly completed stern upper deck.

The deck sections will be attached using two sets of nuts and bolts, I’ve drilled out the holes necessary and reinforced the joints.

4) Hull as of Today:

Here are some shots of the boat with the upper deck and conning tower installed, all that is left is to finish the stern deck, make the bow-stern securing mechanism, lightly sand the whole hull smooth and then it’s off to priming!

That’s all for now folks!

Hello all

After gathering the necessary materials, I decided to build the forward Electronic Component Tray.  My design is somewhat “European” since in addition to a styrene platform and bulkheads, aluminum threaded rods will be used to reinforce the whole setup.  From what I have seen, this design seems to be very popular amongst modelers in Germany and France.

The aluminum rods were cut into the appropriate length, nuts will be used to secure them to the bulkheads

Next the styrene bulkheads were cut and sanded

Holes to be drilled for threading the rods  through are then drilled.  Here, the access space for the main battery has also been marked

Finally, the bulkheads were threaded through and secured using nuts.  Also visible here is my main ballast tank, namely a HDPE medicine bottle

The 7.2V battery fits nicely!

In addition to the two main bulkheads, I also fabricated a middle support bulkhead and platform to house the servo-activated flood valve

Close-up of the support braces.

Since the local hardware stores did not have pipes of suitable diameter, I had to use 3” couplings to construct the watertight cylinder (or WTC).  These sections will be epoxied together to form a pipe of 23” in length.

Styrene inner rims are used to give the glue more surface to adhere to

Two rubber collars with embedded O-rings serve as the watertight seals for the WTC.

…and we’re back!

I know it’s been a while (quite a while actually), but life has kept me very busy for the past few months.  In the spare time that I had, I managed to get some work done on the hull. Continuing from my previous post, the hull was epoxied and sanded over the winter of 2007.  Subsequently, hull plates from the schematics were then scaled up to size, stenciled onto styrene sheets and cut out.  Each was then superglued onto the hull, one after the other, until the entire sub was covered.  As you can imagine, building during week-ends and holidays meant that progress was slow.  By the time the entire plating process was completed, more than a year had passed…

I picked up the work during the winter season of last year.  Over the course of the summer and the past few months, I had managed to remove the inner foam from the master and was left with a clean epoxy hull to work with!

Here is what she looks like as of today:

There is still a bit of light sanding to be done on the outer hull before priming

The hull is split into two removable halves to facilitate trasnport and storage

The inner bracing on the saddle tanks are visible here, these were epoxied onto the inner hull to reduce the tanks from flexing and to strengthen the hull.

In April of 2005, a gentleman by the name of Dougie Martindale generously sent me several photographs of U-52 taken during Second World War, some of which are posted below:

Judging by the look of the conning tower and the black diagonal stripe painted on it, the picture in the bottom right must have been taken after U-52 had been assigned to a training flotilla after June 1941.  Thus, I decided to build the boat as it had looked prior to that date, during its service as a frontboot.  The first two photographs posted depict the boat during its combat career (sometime before the end of May 1941).  One of my main reasons for choosing this time period was because of the unique look of the conning tower attributed to Type VIIbs during that time.  I felt that the twin diesel intake trunkings on both sides of the tower will set the model apart from other Type VIIs on the water!

However, as time passed, work and studies (and laziness) kept me from working on my boat most of the time.  Using the free time I had available on weekends, I managed to correct a few things on the master that I wasn’t satisfied with during the next year.

An amazing stroke of luck came to me during the winter of 2006, when Mr. Jean-Michel Thill graciously sent me a set of high-resolution schematics of the Type VII.  Using these, I was able to make the master even more accurate.  After the foam was sanded into shape, duct tape was applied over the model:

The reason for using duct tape, as explained by Mr. John T. VanderHeiden, is because the epoxy that will be applied to the master has very poor adhesion properties with the polyethylene surface.  This will make removing the inner foam much more easier later on.

After the epoxy was applied, the next step was to panel the hull with styrene sheets.

Ever since my fascination with German U-boats began, I’ve always wanted to build and operate a radio-controlled miniature of the legendary Type VII Unterseeboot.  Originally, a good buddy of mine and I planned to start the project in the winter of 2003.  However, circumstances involving an ongoing RC-submarine build and me moving to my present city prevented the project’s start altogether.

The chance finally came during the fall of 2004 when I decided begin the build.

In retrospect, having only completed one working submarine model at the time (which sunk during its first test), I can honestly say that I lacked the experience needed to undertake a build of this magnitude.  To be a long story short, I was young, wanted to build something cool, so I went ahead with it!

…That was six years ago!!

At the time, I did not have the most accurate plans of the boat either.  Not wanting to spend money to have good plans shipped from the US or Europe, the only schematics I relied on where those found online (thank God for the Internet!).  Specifically, on Mr. Johan Heiszwolf’s very informative site.

Source: http://www.heiszwolf.com/subs/plans/

Fortunately, the schematics included the hull’s cross-sectional body plan, greatly aiding me in the construction process.

In addition, Gudmundur Helgason’s excellent site also provided me with some useful drawings and photographs.

Source: Uboat.net

Since I did not intend to produce more than one hull,the “lost-foam method” of casting suited my needs really well.

Thus, with the schematics in hand, I began the construction of the master model.  Originally, I wanted to use the master itself as the final hull, carving out the space necessary for the watertight cylinder, etc.  However, that proved to be too overcomplicated since it meant that the model had to employ a “dry-hull” design, resulting in a very heavy submarine!  Below are pictures of the master photographed during the spring of 2oo5:

More on this later…