Dhonburi

Discussion in 'North Atlantic Treaty Combat Fleet' started by sinkin321, Oct 31, 2008.

  1. sinkin321

    sinkin321 Member

    Joined:
    Feb 24, 2007
    Posts:
    282
    This build will be going on at the same time as lutzow but will be harded than any I have tried. This is the sister ship to Bob's Sri Ayuthia and is being biult as treaty due to the 1.5 unit min. rule.
    This is a small ship and i do mean small only 2/3 the length of Roberts and only as wide as a fletcher 54cm long x 9cm wide and coming in at about 2 lbs. just to compare, thats about the weight of the two motors shafts and one battery in Shinano everything has to be as light as posable and I think it can be done. I laid out the materials needed to put the ship togeather and weighed them last night and i think with some tweeking it can be done. Again to compare the ship to Shinano the shafts in the big ship are 13 inches and Dhonburi are 4 inches pics will follow.
     
  2. Bob Pottle

    Bob Pottle Well-Known Member

    Joined:
    Feb 2, 2007
    Posts:
    1,948
    Location:
    Halifax, Nova Scotia
    John,
    I'm confident it can be built. The maximum model wt. is at least 3 lbs. The deep displacement is uncertain - the only figure I found was on the 1998 Goff plan but it seems too low in comparison to other coastal defence ships such as the Chinese Ning Hai Class.

    I have been unable to find a deep displacement figure anywhere else and got no reply from the Siamese Navy when I emailed their website 3 years ago. The hull was made deep enough that it will float at scale waterline with 3.25 lb displacement. (It was tested a few years ago.)

    I think the model can be built within 3 lbs total, having built the monitor HMS Gorgon at about 4.5 lbs. (Gorgon is a much larger model). The superstructure will be light (0.5 - 1.0 mm styrene), and if you're successful in vacuum molding the turrets they'll also be styrene.

    We can equip both models with my very light wt. single shot or spurt cannons. I'll probably use a single 260 or 280 motor driving one shaft, with both shafts close to the midline.

    Bob
     
  3. sinkin321

    sinkin321 Member

    Joined:
    Feb 24, 2007
    Posts:
    282
    Bob: I will be using a two shaft one motor gear box, with the motor sitting over the shafts to save room in the boat. I have the gears and the shafts but the shafts have to be cut to fit. Now that i know it is 3lbs i think this will not be as hard as i thought. If you build a spurt gun for yours could you build one for me?.
     
  4. BoomerBoy17

    BoomerBoy17 Active Member

    Joined:
    May 27, 2008
    Posts:
    1,946
    That is tiny! good luck!
     
  5. slow_and_ugly

    slow_and_ugly Active Member

    Joined:
    May 29, 2007
    Posts:
    232
    Hi,
    I think the real challenge here is space, not weight. That is a pretty small ship.
     
  6. djranier

    djranier Well-Known Member

    Joined:
    Jul 24, 2007
    Posts:
    1,756
    In mine I plan on using one of the 30 g refilable bottles with a Palmer regulator, that will be a little under a pound, and a Nimh battery that weights 11 oz. So thats about 1/2 my weight right there. But the rest is all pretty light, so I think it can be done, at 3 pounds, 4 ounces.
     
  7. Bob Pottle

    Bob Pottle Well-Known Member

    Joined:
    Feb 2, 2007
    Posts:
    1,948
    Location:
    Halifax, Nova Scotia
    David,
    Your hull and plans went out today by expedited post. Weight of the entire package was 1.5 lbs. of which I doubt more than 2/3 was hull. With the windows cut out the hull might weigh under 12 oz.

    What motor and gear system are you going to use?

    Bob
     
  8. djranier

    djranier Well-Known Member

    Joined:
    Jul 24, 2007
    Posts:
    1,756
    I have some of Greg McFaddens small single motor dual output gearboxes, and plan on using a Mubachi 260 motor which should work fine on it with 3/4 props I think.

    Thank god for that extra 4 ounces Bob, but I think we should be able to do it. Of course I do not plan on using a water proofbox of any kind, cannot afford the extra weight.

    This one should be pretty fun.
     
  9. Bob Pottle

    Bob Pottle Well-Known Member

    Joined:
    Feb 2, 2007
    Posts:
    1,948
    Location:
    Halifax, Nova Scotia
    David,
    How do I get one of those gearboxes??

    Bob
     
  10. djranier

    djranier Well-Known Member

    Joined:
    Jul 24, 2007
    Posts:
    1,756
    I think Clark, AKA Tuggy has the mold for it now. He may be able to make you one. If not then maybe Greg still can, I got mine from Greg last year, nice and small, and very light weight.
     
  11. Bob Pottle

    Bob Pottle Well-Known Member

    Joined:
    Feb 2, 2007
    Posts:
    1,948
    Location:
    Halifax, Nova Scotia
    David,
    How far apart are the centers of the prop shafts coming from the gearbox? I hope to have one in a few weeks.

    I think I can access everything underneath the forecastle deck by putting the main hatch under the superstructure, so will mold the typical Japanese undulating deck-line and the turtleback forecastle.

    Bob
     
  12. sinkin321

    sinkin321 Member

    Joined:
    Feb 24, 2007
    Posts:
    282
    Bob: I am going with the same belt drive system that one of my fishing boats has had for over three years. The belt and gears are out of a vaccuum cleaner and the belt is short and strong. This will be a trial and if it works should do very well in the little thing.
     
  13. djranier

    djranier Well-Known Member

    Joined:
    Jul 24, 2007
    Posts:
    1,756
    Bob

    I just measured it, the shaft separation is 3/4 of a inch. I figure if I need a little wider, I can use the universals and have a little better seperation that way. But I was not planning on using very big props anyways, the BC 3/4 inch props should work fine with the gearbox.

    This will be made at the same time my new ID is being constructed it looks like, Moldcraft has my plug and is making the mold for her as we speak, so I think I should have the hull in 2 or 3 weeks I hope. Plenty of time to get her ready for the IRC spring regionals.
     
  14. sinkin321

    sinkin321 Member

    Joined:
    Feb 24, 2007
    Posts:
    282
    Ok Shafts are made and in/ rudder post is in and rudder made/ deck is made and ready to install/ shafts will be belt drive and motor mount is being made this week. Ordered two 6 volt 2.3 amp batteries and the boat will run on one only. these are the smallest i could get and are only 2" x 3" x 3/4". Sheeting has been doped and will be done by this weekend. Total wieght so far is 2lbs 8oz.
     
  15. BoomerBoy17

    BoomerBoy17 Active Member

    Joined:
    May 27, 2008
    Posts:
    1,946
    Awesome, thanks for the update, good luck with your build.
     
  16. froggyfrenchman

    froggyfrenchman Well-Known Member

    Joined:
    Apr 8, 2007
    Posts:
    3,358
    Location:
    Dayton, Ohio
    All
    Only weight I can find in Conway's is 2265 tons.
    Doesn't say standard, deep, or anything.
    Good luck.
    Mikey
     
  17. froggyfrenchman

    froggyfrenchman Well-Known Member

    Joined:
    Apr 8, 2007
    Posts:
    3,358
    Location:
    Dayton, Ohio
    I may have to build a Lamotte-Picquet..
    Haha.
    Mikey
     
  18. BoomerBoy17

    BoomerBoy17 Active Member

    Joined:
    May 27, 2008
    Posts:
    1,946
    What was that froggy?
     
  19. slow_and_ugly

    slow_and_ugly Active Member

    Joined:
    May 29, 2007
    Posts:
    232
    It was French cruiser that was involved in the dust-up between the French colonial forces in Viet Nam and the Thai navy.
     
  20. djranier

    djranier Well-Known Member

    Joined:
    Jul 24, 2007
    Posts:
    1,756
    About the only naval battle the French ever won that I know of. Of course I'm not that big of a history buff on the French, so I could be wrong of course.