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 Last update: 02 Sep 06

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  Also the running-kit had some nicely finished bronze parts, I was happy again; it was worth all the money.




  When I saw the quality of the wood in the kit I knew that I had to redo and replace it with better materials. To make a long story short, the only wood parts I used from the kit where the upper deck and the lower deck everything else I could build new from scratch. 

  But why not go in to scale? In order to do so I had to find out more about the real Mister Darby. I sat down and drafted a letter to Halter Marine and told them that I just had purchased a model of Mr. Darby and since I was seeking to make a scale model (except fire monitors and bow thruster), I asked them for some detailed drawings of the real ship. The letter was addresses to the Director of Advertising & Public Relations. Back came a profile and an arrangement drawing of the stock 150-foot tug and also a couple of 8”x 10” pictures, one from Mr. Darby and one from the sister ship Dr. Jack.


           
(The real Mister Darby)

  Knowing that I was going to display the model and entering competitions with it, I took pictures from the beginning to the end and made up a production album.  This is the basics for the information and pictures that follow.

 

  Here are some of the materials I used: regular 5ply and 3ply, anywhere between 1/8” to 1/64”. For adhesives, mostly marine fiberglass resin where used, 5 Minute Epoxy, and some Cyanoacrylate. The final touch was done with Epoxy Paint for the hull and superstructure (spray painted) and Humbrol for interior, railings and decks (hand painted).

Going in to details

Propulsion system: I selected Marx Motors made by a German company, which produces high efficient 5-pole motors of all sizes. They also come with a 360:1 planetary gear system which can be changed to any gear ratio you want and since I was looking for at least a 5:1 gear system, they where just right for my purpose. Today, I believe they are only available in the UK. Here are some technical information’s on the motors:

Voltage - 12-24V max
No Load Current - 4Amp
Stall Current Load - 40Amps

  So I ended up with a motor system, geared 5:1 driving a 4”- 4 bladed bronze propeller. The connection between the motor and the 3/16” stainless shaft is made up by a heavy-duty steal universal (dog bone type). Whenever you use this type, make sure the dog bone has at least 1/32” of play.


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  For the stern tube I used white marine grease, it has the least friction and does not mix with the water. To make this arrangement complete I put thrust washers between the bronze “V” stern tube support and the prop. A word of advice, the large propellers should be balanced before using, if not you will have a lot of vibrations and you will wear out the bearings prematurely!! You’re ending up with a very power full combination indeed.
 

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