External Keel Laminations

Got bored working on the house ( or restless ) , so looked at completing some outstanding issues with the stern sections , The External keel on section 4 / 8 still needed to be done as well as the rudder stub and rudder bearing strut .
First item was the lamination's of solid timber to form the External keel , this was made out of multiple pieces of 100 x 50 kauri  , cut to shape and laminated into position .

 , built another stern tube as with previous stern section and added into lamination as required .

The keel line runs straight from mid-ship rearward , the tunnel in the rear section of the hull means less draft and better protection for the propeller .

The capping strip is slightly wider than the lamination's  so used epoxy filler to create a flat surface on the sides , then covered with multiple layers of unidirectional cloth to create a structual component to take the vibration from the prop and possible grounding capability .

Once the external keel was complete then proceeded on the rudder bearing strut and the rudder stub , the stub is required due to the turning limitations of having a rudder inside a prop tunnel .

In this picture you can see the tube for the bearings and the rudder stub , the stub is cut from the blanks for the rudder already created , glued into position around the tube and filled with expanding foam . Additional glass was then added to form the top of the stub .







After a coat of primer we then fitted  the rotating cradle around this section and rotated into the correct orientation .

This way up looks so much better .

In this picture you can see the finished external Keel , sterntube , tunnel and rudder stub , now just have to repeat this on the other hull , ( damn Catamaran )

A PAUSE IN THE PROCEEDINGS

Haven't posted in a while  , Sections 7 and 8 have been mostly completed by Mid 2017  ,  all sections now surround our house like a fence  . Google earth picture shows most of them and I have added the positions of the last 2 .

The bow of  Hull 2 almost extends over the back fence to the neighbors place .

This has given my Garage back so I was also able to start in on the rudder blades and rudder bearing housing .

Created a half form for the shape of the Rudder

And from this created a number of  fiberglass blanks

These will form the base of the Rudder Blades . Mounted these in a vertical jig and added  multiple layers of  resin impregnated Quad Axial cloth to build up to the desired thickness .
Since it was winter , had to pre-heat the resin so it was runny enough to saturate the cloth as Quad axial cloth is woven very tightly . Very messy job .

The final blade will require some filler on the outside to create a nice finish but by laminating
over a male mold the cloth wraps around the front in a continuous piece so structurally is much stronger .  The Design of the blade is a   MacLear Thistle  which allows for a greater rudder angle and acts like a side thruster at full angle .

Also created the rudder bearing tubes  , these were created like the stern tubes for the prop shafts , only a larger dia and much stronger due to the rudder shafts to be made from 2" Stainless Steel .

These have an internal Dia of 3" and a glass thickness of 5/8" and a length of 30" . The lower bearing will be Vesconite  , a  self lubricating thermoplastic and the upper bearing will be cast bronze .

The Rudder blade pieces ended up with a 3/8 " thickness , 36" tall  , 3 3/4 " width and length of 27"

These will still need to be trimmed to size  , a 4" section needs to be removed and glassed into the propeller tunnel as a base  , the rudder blade swings below this base .

I managed to get an old 2" prop shaft cheaply so will cut this into 2 lengths , add some tangs to it and use it as the rudder shafts . These will be glued into place and the rudders filled with high density foam .


Havn't gotten much done over the last year  , its transition time and this is going to be tricky , next phase of the construction will need to be done in a large shed  and the only way to fund this and the rest of the construction  is to sell the family house , Am currently renovating the house and organising family , not an easy task . Hopefully by the end of the year we will move the sections to the new location and continue the build .

More Wet Sticky Stuff

Have fitted the external keel and prepared the bottom of this hull section for more of the Wet Sticky Stuff , the fiberglass on the sides has been faired into the bottom ply with more filler and more sanding followed by more sanding ( Oh Yeah ) .

Some of the peelply has been left on the sides for additional protection , but since the bottom layer of glass overlaps the keel  , some has been removed .

The bottom layer of glass runs from just above the chine  , across the bottom , over the keel and stops just over the other side of the keel , giving 2 layers at the chine and the Keel .
Problem with this wet sticky stuff is old men leaning over the hull wearing short shirts and exposing their hairy  bulging stomach's to such a messy substance , very messy indeed . Who needs to wax when there's fiberglass around !! .

The Boring Bits in the Middle !

Sections 6 and 7 are the most boring  , very little shape change  , so not very interesting , Same basic Construction though .  Section 6 was built off the bow section and when the shape was stable the bow section was removed and rotated ( earlier posts ) . When section 6 was complete it was used as the basis for Section 7 , when 7 was stable section 6 was removed and now sits awaiting its turn to be rotated .

Rotation cradle is still under the bow section ( 5 ) so need to create a temp cradle to hold it to release the main cradle for its duty  , will do this soon as section 7 is almost ready to come out of the shed and need to create space for it .

The last couple of weeks we have been skinning section 7 in the 2 layers of 1/2 inch plywood.

This is now complete -

 

 

Last weekend we started on the fiber-glassing  of this section

 

Do the sides first  , as they are the easiest , the bottom layer overlaps this layer at the chine .
Glass is installed using the " Wet Method" , activated resin is painted on the plywood  , rolled for 10-15 minutes as the plywood de-gasses trapped air and then we add more resin in preparation for the class cloth , roll the glass on and smooth out , then add more resin to "wet out" the cloth .
Once this is sticky and stable  , we then add another layer of resin and attach the Peel-Ply and smooth out as much as possible .

 

Roll Me Over , Again !!

Section 6 is complete , so need to remove it from the shed as a new shipment of timber is due to arrive  for the next piece of the puzzle  . The bow section has been sitting in the front yard  , after its disconnection from section 6  , so its now time to Upturn it into something more akin to a boat . The cradle was round the back yard under one of the earlier sections so dragged it out and round the front yard and positioned it over Section 5 .

 

 



The Cradle is used for all sections of the main hulls so need to brace the hull inside the cradle , don't really want it moving during the rotation . Also need to bolt-on the semi-circular addons that allow for a smooth rotation .

 

 

 

Now we attach the ropes , chains and other bits and start the rotation ( time to panic ! )

 

 

 

Over we go  , nice and slow , try not to screw it up !

 

 

 

Making progress , ropes pulling from one way to make it roll , ropes in the other direction to stop it rolling by its own will ( don't ask , drama when we rolled section 2 still gives me nightmares)

 

 

 

 

This is when it has a mind of its own and all we can do now is to control the descent  , no more pulling  required , its on its way down .

 

 

 

Maximum load on descent chain at this time but its getting closer to its destination , taking it really  slow .

 

 

 

 

Phew !!! , its down  , I can Breathe again !! , Finally , something that actually looks like a boat .

 

Tomorrow I'll move this section into the side yard and we will look at getting section 6 out of the garage , I'll just remove the addons and manoeuvre this piece out of the way ( don't want to upset the neighbours as its taking up the shared driveway at the moment ) .















Stern tube ,is this where we launch torpedo's ?

Have made the final changes to the fiberglass Prop shaft tubes , have added a bit more beef to the end with the cutlass bearing  , better to be over strong than have a weakpoint .

The basic tube is 10mm thick fiberglass , but the end  has additional material to bring it up to 16mm

Made an initial thin tube by rolling wetted out fiberglass cloth over a steel pipe  , removed when set by slitting it off  , had to be a tight fit as the cutlass bearing is supposed to be a tight fit . Rejoined the tube ( while ensuring straightness and sizing )  and added more layers of cloth to bring it up to the 10mm thickness . Finally added the extra cloth to the cutlass bearing end ( just last weekend ) .
Cutlass bearing is a tight press fit and its as straight as a dye , must remember process as i need to make another one as well ( darn catamaran ) .

Have fitted the tube into a piece of the Keel structure , this will then be laminated into the main Keel.

Thinking about a support Boat

Jigsaw will require a tender / support boat with it as most of the construction will take place when its already in the water  .
First thought was

With a cross section of

A bow door like a landing craft and a fully enclosed floor for boyancy , problem is its not wide enough for all the jobs it needs to do  , Maybe a catamaran version ?