Forum

bulkheads

The first pic that Green has posted, does show a 'Schottel' drive unit at the left of the plan, no wonder he is confused.

6 years ago by Kipper

Forum

bulkheads

The plan at the top of the thread shows a specific Water Tractor tug plan specifically designed for the VS drives, including the large straight keel at the stern. I suggest Green72West should either use VS drives or use another type of hull for s.

6 years ago by reilly4

Forum

Zyx drives v shottel!!!!

Thanks for replying RNinmunich. I know the Difference between schottel and voith prop. I pointed out in post i wanted to use In your words "z drives" on my model iO am attempting to build. I am new to this so give me a chance to learn without some negative remarks!!! OK. I will take your advice and will leave hull alone. I could do with advice from Members of installation of "z drives" in Bow of the hull. Thanks GREEN.

6 years ago by green72west

Forum

bulkheads

Hi Gerd, it's not my plan! The plan is from 'green72west' who started this thread and seems to be confusing Schottel and Voith-Schneider. Either that or he wants to use two Z-Drives instead of the Voith drives. His intention is not clear. Either way he doesn't need to cut chunks out of the keel, that's nuts😲 Cheers, Doug 😎

6 years ago by RNinMunich

Forum

bulkheads

Hi Haig, seems to be a common mistake to get s (Z-Drives) and Voith - Schneider confused with one another! First two pics show a twin Voith propeller on a tug hull (as on the plan above) and the operating principle. 3rd pic is cross section of the Z-Drive as produced by the Schottel company. it is a 360° rotating 'pod'. Newer versions have electric motors built into the pod and don't need the mechanical Z transmission from inside the hull. With such pods under bow and stern even bow and stern side thrusters are redundant 😊 4th pic is the Graupner version, Mk II. https://www.graupner.com/Schottel-Drive-II-new-version-/2335/ Cheers, Doug 😎

6 years ago by RNinMunich

Forum

keel/hull info

thanks for answer "bulkheads!!!" doug. I am not getting VSP units!! THE £200 each has something to do with decision. I am getting when "ready" Graupner unit 11 [2335] x 2. What i would like to know, [i have 1000 questions] do i need to have 2 rudders???. thanks, green.🤔🤔

6 years ago by green72west

Forum

keel/hull info

Hi Green72west, The s will maneuver your boat 360 degree's about! Can't wait to see your build blog!

6 years ago by figtree7nts

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keel/hull info

The s rotate so you don't need rudders.Enjoy your build.

6 years ago by Donnieboy

Forum

s

Hi Steve She looks quite a compact boat, and with the family connection even nicer. Have you got plans for her? How did you get them? Happy building! Edward

8 years ago by cenbeth

Forum

s

Hi Guys, Are the cem s pre lubricated? Just about to fit them into a tug.as you have to dismantle them to fit them I have found that the upper gearing is bone dry, due to the cost of these units I don't want to find out the hard way. Steve.

8 years ago by Stour-boy

Forum

s

Edward,the assembly as you put is in the shape of a harbour tug called, W.H.Parr, and operates in Port Nelson N.Z. I wanted to build this tug as it is named after my mothers cousin. it was built in Dunedin in the early 70s. I was able to obtain some drawings and have built it from scratch, I have had some help and guidance from club members. it got its bottom wet last Wednesday for a brief period, it sits square on the water but slightly bow down so a little bit of shuffling about with batteries might get me somewhere !! I am a bit reluctant to add weight at the moment but I built it to carry 2, 12v.7amp lead acid batteries. It's scale is 33 to 1 which makes my model 2' long so it's a bit tight for space inside. If you look up W.H.PARR on the internet you should see what I am building. Steve.

8 years ago by Stour-boy

Forum

s

It sounds like an interesting assembly! When do you expect to have her on the water? Edward

8 years ago by cenbeth

Forum

s

Edward,experiences so far, to fit the unit into a hull you have to dismantle the drive by removing the gear retaining circlip and then pull of the large crown wheel,mine were both very tight,then lift of the rudder gear wheel you can then remove the lower gear assembly. The plastic tube that forms the upper part of the lower housing that turns in the mounting(still with me)? I put some felt inside and put some engine oil in so that it can be turned upside down and still retain a bit of lubrication. This was before I was aware that the lower section is lubricated with water!!! On fitting it into a the boat the supplied circlips had to be replaced because I was a bit heavy handed so I found some s/s circlips. One drive is a bit noisier than the other but early days yet. Steve.

8 years ago by Stour-boy

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s

Hi Steve No, I'm just interested and at sometime in the future may need to use one. More importantly, others using this site will get to here about your experiences with it. All the best luck Edward

8 years ago by cenbeth

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s

Cenbeth,have you had any experience with these drives ? Steve.

8 years ago by Stour-boy

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s

It will be interesting to hear what it's like during use and whether you experience any problems. Edward

8 years ago by cenbeth

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s

I phoned the shop that I bought them from and they were no help at all. Then I contacted their suppliers through info found on the box that the drives were supplied in and it seems that the lower gears are lubricated by the water that they are submerged in so don't need grease,but the top gears are lubricated by a light lithium based grease. So there we have it. Thanks for your input John. Steve.

8 years ago by Stour-boy

Forum

s

I would contact the makers as they will tell you exactly what and if you should use . Good luck John

8 years ago by onetenor

Forum

Servo current draw.

Thanks for your input gents looks like a big rethink is on the cards. Dave I think that YouTube video is a bit over the top for my little tug.withall the heavy engineering I am surprised that there were not any metal bracing so between the drivers and driven gears. I will contact the servo shop to see what they recommend. Havelock there isn't any provision for a pull pull system so I will beef up the control rod by soldering/reinforcing it. And yes they are the s that I will be using. Thanks agaI n Steve.

8 years ago by Stour-boy

Forum

Servo current draw.

HI Dave,thanks for the reply, I Take it that VE means positive ? As Haverlock and yourself use the expression. The drives I am using are the CEM 040 units on a 2ft long tug so I think it will be a (suck it and see) situation.

8 years ago by Stour-boy

Forum

Servo current draw.

Thanks for that Haverlock,what a can of worms,there are at least 2500 different types so where do you start when deciding which ones to use ? Going back to the feeds for the servo it looks like the three wires are pos,neg and what I call a trigger wire,so as long as they come from the same power source that's fine ? I am building a harbour tug with azimuth s with 180 degree steering and using astern for the other 180 if that makes sense both drives independent of each other. is there a gyroscopic reaction that would make it necessary to use heavier servos ?

8 years ago by Stour-boy

Forum

electric v drive

HI Guys, I have seen pictures of a v drive system,motor under shaft and reduction gearing mounted on engine mounting bracket with NAVY in the title. Can anyone enlighten me as to who makes it and where I can get one, I am also looking for 2 s , Thanks for reading. Steve.

8 years ago by Stour-boy

Response

Building a Kort Unit

HI Jeff I was suggesting version two which you have tried. This will certainly let more water through the nozzle. if you silver solder the legs to the Nozzle and silver solder a central ring to fit the prop shaft housing this would be structurally strong. Should be easy enough to devise a clamp from this ring to the housing Cheers dave

10 years ago by Dave M

Response

Building a Kort Unit

HI Dave, Thanks for the reply. I am not sure I follow what you mean. Just uploaded the 2 versions that I tried. See if that's what you are talking about. Version 1 is "clunky", and version 2 is not that strong. Regards Jeff

10 years ago by Schifty1

Response

Building a Kort Unit

Looks quite functional but a bit heavy. You have used two mounting points and I wonder if three would be more secure and allow for smaller arms, allowing more water to pass? If you fix the arms to the nozzle and provide a ring in the centre this could be used to hold the shaft in place with a simple fixing. The Graupner unit seems to have a large plate allowing the whole unit to be removed for servicing,

10 years ago by Dave M

Blog

Building a Kort Unit

I started to build a "Rhine Tug" it's a pusher called the Egrete, from a set of plans that I bought. Selected it because it had some neat challenges. 1st was making the telescoping wheelhouse so that the pilot can see over 2 containers stacked on top of each other. The second was designing/building a KORT unit. The reason I am starting this blog is to see if any others have build their own Kort drive units. Size wise, I am using a 2" dia. nozzle with a 1.75" propeller. I have the gearing/motor/rudder all worked out and operating, what I don't have is a good method for securing the back end of the propeller shaft to the nozzle. I am looking for suggestions on how to make an assembly that can be assembled/disassembled. The attached photos are version 1 & 2 of what I tried, and a photo of the entire assembly. Thanks in advance for helping. Jeff

10 years ago by Schifty1

Media

Scratch built SDM MkII tug built by UmI Ryuzuki

Scratch built SDM MkII tug 1/48 scale. Hull started out as polystyrene foam and plywood. Started July 29,2006 and in the water by Aug. 11th for sea trials. Detailed over the following 18 months. The model is powered by 12vdc using Graupner Speed400-2.33:1 gear drive, and the small Graupner s #1761. Separate ESC and Steering control for each drive. The Lighting is 3mm LED cast into clear, or tinted, polyurethane lamps. It sails the Pacific Northwest, USA, homeport Portland, Oregon.

16 years ago by Umi Ryuzuki