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[woodbutcher]

well my model of the Northern Dawn looks reasonably good, but the exponentialy diminishing displacement has led to problems. there is a net,power skiff and power block left to install and opperate, but the decks are already awash. so it looks good on the shelf. the future will ,if will is there, bring the building of a new hull with an extra two inches of depth before the turn of the builge,which should allow plenty of extra displacement which should allow for more functions also.I will use all the super structure etc. over again, so it is only  a matter of a couple weeks work, but will must be found after let down. Al .    p.s. photo of it on the shelf.

[derekwarner]

woodbutcher.......you do have the consolation of a brilliant looking model...........[on the shelf yes] but still a  great example model........

It would be a pity   to remove the deck houses from this completed model..........for a new hull...........just reflect on this for a while  ...........Derek

[woodbutcher]

maybe so but it would look the same when in the pond and it would give me the satisfaction of finishing the model and setting the net.  Al.

[HS93 (RIP)]

I had been building a steam tug for a number off years, only to find I would have the same problem as you. I was in the position that no paint had been sprayed so a new superstructure built a lot lighter, which I didn't think was possible for the boat but I lost a lot of weight, I had also just started another boat that was going at the time to be a quick build to experiment with drive system, with the tug still in my mind i set about weighing things from day one as I did want it light and was surprised at the weight of bought fitting kits I was able to loose over half the weight if not more as i made them myself from brass and alloy. although I really like working in metal I have found that I am having to work more with plastics to keep the top weight down and was even thinking of having two superstructures one to sail and one built the way I want for display, I hope you sort it as it is a beautiful boat.

Peter

[woodbutcher]

itwas raining here this afternoon and as I'd finished building and painting the two chipper barges for my tug Lloyd B. Gore and soon to be built Sealane I decided to layup a new keel for the Northern Dawn's new hull. Layed keel, cut rabit, cut a stack of bulkheads and spacers, took them home then got carried away and glued a lot together. Now will have to mill a couple lifts of planking and get busy. Threw in a couple batteries and a motor to see, will give me lots of room, way more displacement and should give added stability. Just by redrawing lines and adding an extra 1 1/2" to depth along verticle line of hull. Al

[woodbutcher]

couple more from above, Al

[woodbutcher]

more photos of the new hull. Al

[woodbutcher]

still lots to do (ribs , shelf, deck beams,vertical stern planking etc.) but while waiting for epoxy filler to cure I drew up the plans for the power skiff (6" x 3" x 1 1/2") which sits on deck behind the net drum,usually on top of the net . The skiff will require its own three channel radio. Al

[woodbutcher]

new hull progressing

[woodbutcher]

a bit more done to the new hull.Al

[woodbutcher]

while waiting for things to dry, I made a couple plugs (tug Sealane and tug Harken #3)then made some fiberglass molds then some glass hulls then cut the plugs in half and made half hulls.Al

[woodbutcher]

Some more

[woodbutcher]

now the Harken 3, old model had suffered from tipping over illness, decided to fix with new hull.

[woodbutcher]

Harken 3 finished.

[woodbutcher]

and the half hulls stuck on the wall. Al

[woodbutcher]

Did some more on the new Northern Dawn hull and have started to move things over from the previous hull. Al

[woodbutcher]

one more of the Norther Dawn, and I did some more on the Sealane, deck beams and installed the batteries. Al

[woodbutcher]

NorthernDawn rigged and tested,floats right, still a little tender. Harken 3 done. tug Sealane progressing.Al

[woodbutcher]

some more shots of  Sealane.Al

[woodbutcher]

and a couple more. Al

[cmpang]

one more of the Norther Dawn, and I did some more on the Sealane, deck beams and installed the batteries. Al

Hi Woodbutcher...

the key point of a boat's stability is the height of its CG, being the lower the better..
while totally agree on making a deeper hull will correct the stability problem... one thing I see in your picture is you are using the seal lead acid (SLA) battery... which results in rasiing the CG so high that it is no use to save just a minute amount of weight by reworking on the fittings above the deck...
one thing that helps is to use LiPo battery.. choose the one as thin as possible.. and re-ballast the boat with lead sheet.. thin lead sheet and lay them at the lowest bottom of the hull... in this way, even the worse stability boat will not tipped over on the water..

just my 2 cents..

 

[woodbutcher]

Northern Dawn, at scale speeds and conditions is quite stable ( motion is quick and comes back up quickly) and I'm satisfied. In full size this boat rolled over and sunk as did one of its sister ships.But still a fine looking boat.