Sunday, December 30, 2007

Vacuum bagging the first lamination on the daggerboard.

Cutting the 6oz carbon cloth and fitting it on the daggerboard. My plan was to hold the board at one end and laminate it down from the leading edge to the trailing edge.

I was not very happy with my hand lay up of the cloth. The cloth stretches very easy. However in the end we get it all in the vacuum bag. I cannot imagine getting good adhesion on a part like this without the use of vacuum.

Here is the daggerboard straight out of the bag with the excess cloth very roughly cut away and presented to the family on the living room floor. Not a perfect job but I can work with it. It is now on to the uni-directional carbon fiber.

At this point the daggerboard weighs in at ~ 8-9 lbs.

Saturday, December 29, 2007

More daggerboard fairing and preparation for sheathing

I found the templates traced and cut out from the full sized plans to be very useful. I used hardboard from one of the boy's old school projects. Above you can see that I could actually get them to all stand up on their own. At this point I was getting close to final shape.
On each side of the trailing edge I cut the foam down to the fiberglass cloth that I had laid down when gluing the two foam pieces together. I then filled up the edge with fairing putty. Same process for the other side. I thought that this worked out very well.

The rotary tool showing at the top of the picture allows me to make rebates far easier. Santa was good to me this year. The above rebate is for the carbon cloth. My 50" wide cloth will not allow covering in one piece with the fibers at +- 45 degrees. You can also see the putty on the trailing edge, the larger rebate for the uni fiber and the core still showing, wrapped with the carbon fiber.

Thursday, December 20, 2007

Daggerboard fairing begins

I had to think about how to position the wrapped core and keep it properly centered in the foam block. I was struggling with this and then suddenly it occurred to me that I could re-use the scrap piece of foam that I had cut off to taper the core cut out to the correct thickness. This was a scrap piece and I had to recover it from the garbage heap.. My thought was that the piece could be used as a spacer to locate the laminated core in the centre of the foam block. There would be no need to create any new spacer or other method.

You can see how much foam is actually cut off one side the core to reduce the core thickness, below.
Remember that the daggerboard sections get thinner the farther you go down, and this is just one side.

Below you can see the core correctly located within the 2 inch thick foam block.

I used some polyurethane glue to lock the core into place and proceeded to machine the 4" wide rebate down the length of the core insert. I ended up using my Dremel tool with a router bit to cut the rebate. I used the inserted core as a guide to determine the correct depth of the rebate. I have since asked Santa for the proper tool.

Then the fairing begins. From the coarse we go to the fine. The initial fairing actually goes very quick. You can see above the templates of sections A-F lying on the work table. They are invaluable. With my experience of shaping the float bow caps I expect the fine touches to be interesting.

Monday, December 17, 2007

Daggerboard core lamination

I am continuing to learn that much of boat building, it seems, is in the preparation of an operation. Like a doctor one must surgically prepare the 6oz. twill carbon cloth at +-45 degrees, cut the peel ply and plastic, put on the blue gloves and mix the epoxy.

Above you can see the core foam with the high density insert in the centre.

I am not a fan of wrapping fiberglass around objects. This time I decided to use the plastic over the peel ply so that I could wrap the laminate tightly with packing tape.

Note the taper in the lower foam piece. I had to carefully reduce the thickness of the pieces to a) allow for the rebate for the uni carbon fiber and b) to accommodate the reduced thickness of the daggerboard sections as you go down.

The operation went well and here are the 3 sections of the core. I'm debating whether I need to join them before inserting them into the foam. Peeling the ply was quite difficult and next time I will make sure some ply does not get saturated, to give a reasonable location to start peeling without having to dig.
Here are the inserts back in the foam block. Next step is to glue/bond them into place, cut a rough perimeter and start the fairing.

Saturday, December 15, 2007

Parts from McMaster-Carr

I have sourced the following parts from McMaster-Carr
Still have to do a double check on the parts and the quantities include spares.

Bow web bushing for bow pole Qnty 2

No-Lube Fiberglass Sleeve Bearing for 1/2" Shaft Diameter, 5/8" OD, 1" Length
In stock at $5.29 Each

Bow pole bushing Qnty 4

UHMW Bearing Flanged, for 1/2" Shaft Dia, 5/8" OD, 1/4" Length
In stock at $4.34 Each

Flanged bushings for Rudder pivot tube and gudgeon Qnty 7

PTFE Flanged Sleeve Bearing for 1/2" Shaft Dia, 5/8" OD, 1" O'all Length
In stock at $5.21 Each (see below update)

Plastic end strip for Rudder case

(Same as 8492K15)
Acetal Copolymer Sheet 1/2" Thick, 12" X 12", White
In stock at $34.10 Each

Nylon nuts, bolts and washers - rudder case

Nylon Hex Head Cap Screw 3/8"-16 Thread, 1-1/2" Length
In stock at $6.67 per Pack
This product is sold in Packs of 25

Off-White Nylon 6/6 Hex Nut 3/8"-16 Screw Size, 9/16" Width, 11/32" Height
In stock at $14.32 per Pack
This product is sold in Packs of 100

Nylon 6/6 Flat Washer 3/8" Screw Size, .390" ID,.750" OD,.057"-.067" Thk
In stock at $6.81 per Pack
This product is sold in Packs of 100

I've been reminded that the McMaster
PTFE Flanged Sleeve Bearing is not equivalent to Ian Farrier's custom PETP bushing. PTFE is not strong enough for the rudder. I will not be ordering these. I can source raw stock PET-P locally from Johnston Industrial Plastics.

Sunday, December 09, 2007

Starting to glue the high density inserts into place.

I did my best to nest the required number of pieces. A1200 Core-Cell is not cheap!

I'm using the polyurethane glue to glue in the high density inserts. The foaming of this glue is quite amazing, it expands to fill in all the voids.

Saturday, December 08, 2007

Daggerboard high density and core cut outs.

I had to get a longer blade for the jigsaw but the areas for cutting out went very quick. On the left is the core piece that was cut out. I will reuse most of it except for the 16 in that need to be high density. Next step is to cut out all the pieces of high density material (I need to stack 5 layers of the 10mm thick a1200 high density foam) and fill up the holes that I have created.

The MDF on the left is soon to become the molds for the wingnet rails and supports.

I had a pleasant but short visit today from Jim and Doug MacKenzie who are building their F22 in London Ontario. They let me know that planking the main hull goes very fast. Comforting, if I can ever finish the floats and get to that point.

Friday, December 07, 2007

Daggerboard profile transferred to foam block

I got to work on the living room floor tonight tracing the profile information that is available . I traced the information using carbon paper where possible and a long ruler for marking measured lengths where required.

Note that I first made a positioning error on the lower daggerboard profile.

The high density insert areas are marked out and I guess the next step is to cut them out.

Wednesday, December 05, 2007

Daggerboard construction starts with the construction of the basic foam block.

It's too cold to work in the garage so I decided to build up the daggerboard from two layers of 25mm thick corecell A450 offcuts from Noahsmarine in the basement. The offcuts are in 46 in lengths so joining the foam sheets was the first task to complete. If you look closely below you can see that I use sharp little tooth picks to help keep the foam sheets in line while the polyurethane glue cures.

Once the foam sheets are together I've used an weak epoxy resin cabosil mixture to glue the two sheets together to get to the required 50 mm thickness for the daggerboard. You will note that I have laid down a sheet of 9 oz glass cloth down what will be the trailing edge of the board. This will be to provide extra strength in this thin section.

Then they are clamped together.

Next is the transfer of the daggerboard profile to the foam, and the areas that require high density inserts.

Sunday, December 02, 2007

First float half lamination complete, hull re-oriented and quickly weighed

The first float half outer hull sheathing is now complete.

And the float frames have been reversed and the float re-oriented for the next half.

We did a quick weigh with the two bathroom scales, with two people with and without holding the float. It looks like the float weighs about 90lbs with the other half and the deck still to be laminated. There is still a chance I can meet Ian's theoretical weight of 112lbs for a float ready for painting.