StrongBack

Today we will finish the basement.

After cutting the pieces according to drawings we started aligning them on the floor.

And then waited for the train to come.

Now is time to place the legs

After raising it at 180cm height

Preparing for the Strongback

The frames have been completed and piled on one side.
Their size is really impressive

A little more work has to be done on bulkheads

On BH B we opened a 50x50 cm hatch for access to the anchor locker and placed vertical reinforcements with a 40x40x4 Angle 6082 Alu.

And on BH K the same vertical reinforcements

We then wanted to tack the bathing platform just to have a piece that looked as a boat and believe we were sitting on the platform with feet hanging down in a blue water lagoon.

The result is that we found out that it does not fit as expected. We probably will need to reshape it later. So far so good.


Now we start preparing for the next phase. Setting up the strongback.
The space was cleaned and room made for the basement.

We decided to build the strongback in pieces of 150mm thick iron hold together by 10mm bolts.
This will make it easier to remove it at the time of turning the hull. There will be no need to cut iron and thus no contamination of the alu at a point when it would be very difficult to remove the iron particles.

Frame Distorsion

To check that no twist occurred on frames while welding flanges we used a laser level

 And then checked again on the lofting floor

Flanges Bending Flanges....

We found a way to make S shape curves

Bending on a shape with the desired radius

Good but at this point we found out that we placed the horizontal bar on the wrong side of few frames. So we had to reposition them.

Flanges

All frames have been completed. There is a bunch of them piled up in a corner of the shop.

It is a great satisfaction. An with no welding distorsion untill now.

To achieve the best quality possible, we asked for a RINA certification of our weldings.
Here is the inspector checking our work

Now we can boldly go on with the flanges
The 6082 T6 alloy is much more strong then the 5083 used untill now and difficult do bend.

Still very difficult to obtain the desired radius.

So we go on with frame A

Finally it is completed. Continuous welding on both sides at corners +50mm. Chain welding 75+150 both sides

Then we continued with frame C. A little bit more complex.

So to make all  different turns we went back to manual bending

We hope to complete the flanges in few days. We can't wait to see the skeleton on the strongback.

More Frames

Framing goes on

Web frames are placed on the lofting floor for accurate alignment and blocked together.

Then side A is welded on the floor.

A reinforcement bar is placed horizontally on every frame at the level of the DWL.

Run in run off is used at every BW.

Side B welding is done on a table for sake of back well being

So frames start to pile up quickly

One More!

Good work we have almost finished stem ONE: welding web frames

Setting up Frames

Web Frames Reinforcement

We finished as planned with the pipe reinforcement.
A lot of them around 120

Frame Welding

Now we are ready to set up the frames. We placed spacers to keep the web frames flat on the lofting floor accounting for the 2cm of pipe.

 The blocks will also help to prevent distorsion and allow placing or run-in run-off pieces
 At this point it was time to place the transverse support bars for the frame.
The nesting file included holes in the frame for this. But at a closer view what appeared to be holes of different sizes

it was only incomplete perforation by the plasma cutter. In fact all the holes should have been of 8mm diameter. So we now must drill all of them again.

The frame is now ready to be welded on side A.

The welding is complete with the run-in and off

And now here is the first frame, J, ready.
It start looking as part of a boat!