Another ARKMODEL VII Build Blog

[rwtdiver]

Today I finished up the rudder parts installation using LEGOS gears and brass tubing, brass rod, and brass sheet metal. I realize some will say the plastic gears will not last! Having build MANY LEGO motorized kits, I can tell you from experience they will last!



I designed this entire rudder assembly so that it could be completely taken out of the sub if I ever had to replace any of the gears! The brass plate at the top of the mechanism on the first photo is the adjustment nut that will allow me to adjust the tension on the gear drive system. I am going to take the assembly out of the sub tomorrow to do some final finish and clean up work.

Rob
"Firemen can stand the heat"

[rwtdiver]

Looking awesome, Rob! Well done!

Bob

Thanks Bob,

Still in design process, but I think it will do the job!

Rob
"Firemen can stand the heat"

[RCSubGuy]

Looking awesome, Rob! Well done!

Bob

[rwtdiver]

The rudders are a big let down in that kit. Like the cylinders they produce, Arkmodel's products were put out by engineers, not builders. A new rudder linkage layout is needed.

What Dwayne Hill did in his 48 scale boat was actually use gears. Here is a quick sketch I did of the arrangement. Note that by using a large central gear and two smaller on the rudder shafts, you get 2:1 or more of gearing, reducing required throw from the servos.

Well after spending the afternoon digging through all my old LEGO blocks and gears I came up with a possible rudder application!



The design works, and it really gives a lot more rudder throw than the ARKMODEL linkage design. It's designed so that if I ever need to change out one of the gears the rudders themself can be removed and the entire gear assembly can be removed for repairs! I still need to clean up installation and add the control horn, then it's good to go!

Thanks for the idea Bob!!

Rob
"Firemen can stand the heat"

[rwtdiver]

The rudders are a big let down in that kit. Like the cylinders they produce, Arkmodel's products were put out by engineers, not builders. A new rudder linkage layout is needed.

What Dwayne Hill did in his 48 scale boat was actually use gears. Here is a quick sketch I did of the arrangement. Note that by using a large central gear and two smaller on the rudder shafts, you get 2:1 or more of gearing, reducing required throw from the servos.

Interesting concept Bob! That looks like it could work and allow for more throw on the rudders!

Thanks for sharing that sketch.

Rob
"Firemen can stand the heat"

[RCSubGuy]

The rudders are a big let down in that kit. Like the cylinders they produce, Arkmodel's products were put out by engineers, not builders. A new rudder linkage layout is needed.

What Dwayne Hill did in his 48 scale boat was actually use gears. Here is a quick sketch I did of the arrangement. Note that by using a large central gear and two smaller on the rudder shafts, you get 2:1 or more of gearing, reducing required throw from the servos.

[rwtdiver]

Today I started more work in the stern section. As you are aware the Type VII sub has dual rudders. After a trial fir of the rudder horns, I am not satisfied with the horns themselves!



Therefore I decided to manufacture two new horns from brass, these will give me a more secure base to install the rest of the rudder linkages.

Rob
"Firemen can stand the heat"

[rwtdiver]

With all the required bulk head removal completed, the WTC fit in very well. Quite pleased with how it runed out!



The motor shafts will require universal joints (no problem) and the stern dive planes, and the rudder linkages are also very close as well! With this fabrication completed to this point, I would say that the 80 mm WTC that I purchased from Nautilus drydocks is a really good fit for the Arkmodel Type VII boat!

Rob
"Firemen can stand the heat"

[rwtdiver]

Today I removed the two bulkheads from the stern (aft) section of the hull to accommodate the 80 mm WTC.







After removing the bulkheads using razor and nippers, I sanded the areas, cleaned them with denatured alcohol and the two coats of water base acrylic paint and then two coats of matt finish clear coat.

This finishes up the required bulkhead removal in order for the WTC to fit into the hull!

Rob
"Firemen can stand the heat"

[rwtdiver]

Today I started on the forward dive plains.



As you can see by the photo, the control rod is square, and the control arm has a round brass bushing! Well, needless to say that is not going to fly. These are parts that came with the kit.







So, I fabricated a brass control horn and soldered a 1/8" brass rod for the control rod. I also installed 1/8" brass sleeves into the hull to accommodate the new 1/8" brass rod (control) and the new brass control horn. This turned out to work very well. My next concern will be the rudder control system!

Rob
"Firemen can stand the heat"

[rwtdiver]

Today I removed two bulkheads from the center section of the hull at the forward end of the center section!



This was done so that the 80 mm WTC would fit in the hull itself. The center of the ballast tank on the WTC is in exact center line of the hull.



Now that I have the 80 mm WTC compartment in its designated position in the hull, we can start on the hull build up!

Rob
"Firemen can stand the heat"

[rwtdiver]

Great start Rob! Will you be cutting the hull open at the waterline or using the kit’s original hull separation?

Thank you neitosub!

No, I will not be cutting the hull! For the type WTC that I will be using plus I will not be doing any extra add on features, just the basic simple running sub. Just the top removable deck will give me the required access that I will need to get into the interior. I am just going to keep it basic simple!

Rob
"Firemen can stand the heat"

[neitosub]

Great start Rob! Will you be cutting the hull open at the waterline or using the kit’s original hull separation?

[rwtdiver]

I just found out that there is another person out there building the ARKMODEL 1:48 Scale Type VII also!

His name is Bill (cgbillb) If you are reading this, are you going to put up a build blog on your build as well? We both have the same kit and the same 80 mm WTC that we purchased from Bob Martin (Nautilus Drydocks)

Rob
"Firemen can stand the heat"

[rwtdiver]

This will be my second try to post on my build blog! Have had a couple of issues and not sure why!? But here we go!!

I have received advice from Nick (Monahan Steam Models) Bob Martin (Nautilus Drydocks) and the MASTER himself David Merriman III! As most of you are aware, Nick is building the same ARKMODEL Type VII that I am. So, I will be going to his build blog many times I am sure to get advice from him. I will also be using the YouTube videos that Bob Martin has posted showing a complete build of the ARKMODEL Type VII.



The advice that I got was to make sure that I scrubbed ALL the plastic parts on this kit using soap and a scrub pad! (Photos Posted) This is to make sure that any residue from the manufacturing process is removed. This residue could hamper the gluing, fillers, and the final finish work from adhering to the plastic. Very good advice!

Rob
"Firemen can stand the heat"