Almost ready for flip and slide

This past weekend I got the center bulkhead glued into place, fillets smoothed down along all three bulkheads and a layer of tape laid in place. I'll let this cure as is for a few days before starting to remove all the screws holding the foam into place. Then we can work on lifting it from the cradle, flipping it over and sliding it over to the other side of the shop in position over the inner half.

It's taken a while and I've learned a LOT!

Once the two halves are glued together and wrapped with glass it'll be time to start the fairing/painting learning curve. This is the part of the build that folks complain about the most so I'm not super excited about it...

Depending on finances, I'm hoping to finish the starboard float by end of year.
(I have my doubts though)

Fillet in place - waiting for a partial cure before laying over with a 6" (300mm) wide piece of 18oz DBX tape.

Center bulkhead in place at the correct angle.
I chose not to cut this one in half due to the access hole.
I have a feeling that it might make things a little bit more difficult when gluing the halves together.
But on the other hand, I won't have to worry about bulkhead integrity, extra tape thickness in this area and lining up the edges accurately. 

Bulkhead progress

So far so good... I'm mostly happy with the way the recessed deck plate turned out.
I still need to wrap the raw inner edge with a layer of tape to seal and reinforce the opening.
After that, I need to mark and pre-cut the chainplate slot before finally gluing the bulkhead into place and then finish up the filleting on the other bulkheads.

Once that is all done, we can finally begin removing all the screws holding the outer float half in place so it can be flipped over and positioned over the inner float half for bulkhead alignment and gluing together.

Vacuum bagging materials removed. Most of the peel-ply is still in place.

Scraps cut off from bulkhead trimming

Bulkhead weight after trim but before removing deck plate section

Recessed Deckplate in position.
One of the things I'll need to pay more attention to next time is the fairing around the reinforced clamping areas.
I can fix this with a bit of lightweight filling, but it would have been better if it were fair to begin with.

Peel-Ply still in place on both sides of the bulkhead

Close up shot of recessed area and solid reinforced epoxy clamping area

Recessed Deck Plate - Foam Test

I was happy enough with the previous test to move ahead with the second test on scrap materials.
Previously, I had applied a layer of glass to one side of a foam panel and let it cure.

The first step is to mark and use the router to remove the foam core from the four deck plate pinch points then back-fill with reinforced and thickened epoxy. Once that cured I used the router again to cut the recessed area before rounding over the edges and applying a layer of carbon scrap pieces via vacuum bagging to see if the fabric will take that radius and fit tightly along the edge.

Details below:

Pinch Points routed out down the the lower layer of glass without penetrating.

Backside of panel showing routed out areas

Pinch Points back-filled with thickened epoxy and left to cure overnight

Recessed gasket area routed out to 7mm depth

Vacuum Bagged surface over some Carbon Fiber scraps.
Note: I free-handed an additional cut on the inner side of the recessed area to ensure that the fabric had a wide surface to lay flat against. This area will be removed later on.

Curing under vacuum

The shop is cold, so I put my heating blanket over it to make the resin kick in 1/3 the time.

Checking out the cured panel.
The main concern is checking out how the fabric lays up against the outer edge of the recessed area.
Next time, I will cut out the inner section of fabric to allow for easier fabric movement along the edges.
You'll also notice an intentional fabric overlap along the center of the panel.
I wanted to know how this would impact the final part, however I don't plan to have fabric overlaps over these areas.

This looks really good to me.
Once the inner section is removed, the recessed gasket area will receive another layer of fabric that will tie the top and bottom layers of fabric together and seal the raw foam edge.

One more picture

Recessed Deck Plates

This past weekend was spent working out the requirements for a recessed Deck Plate installation and then sorting through the details and finally working out a repeatable process.

I'm SURE there's an easier way to get this done, but I'm stumped for now...

While I'm not quite "there" yet, I am making some progress towards the goal.

Initially I was thinking I might need a Hi-Density bead of foam for the gasket area to sit against, but that was quickly disregarded after a forced attempt at crushing the plain foam with the clamps failed to do much more than produce a slight dent. Once the plain foam has a layer of fabric over it, this will no longer be any concern.

The next consideration is providing a solid clamping surface for the four clamp points.

... But I'm getting way ahead of myself, it's probably a good idea to list the requirements before running through some solutions.

Note: 

I am assuming that the "top" surface of the foam will be plain while the "bottom" (or back) surface will already have a layer of fabric in place.

1. Bottom surface must maintain vacuum integrity throughout the installation process.
    - This will allow for infusion of vacuum bagging on the top surface
2. High Pressure Clamp Points (x4 for this Deck Plate size) must be a solid laminate to avoid foam crushing
3. Top surface must have a slight "round over" at the rebated area to facilitate fabric lay.
4. Recessed area must provide a flush or nearly flush final installation.
    - In this case I'm much more concerned about lines getting caught under the hatch and ripping it off or toes getting smashed than I am about water dripping inside whenever the deck plate is actually removed.
5. Gap around outer edge not to exceed 3-4mm
    - Again this is to keep lines from slipping between the gap

Probably the biggest issue for me was just working out the router distance, kerf considerations and maintaining the proper corner radius while reducing or enlarging the size of the pattern. Now if I was a cabinet maker of worked with this situation more often I could have whipped some templates out in no time at all using some "tricks of the trade", but figuring it out from scratch really made my brain hurt.

Anyway, after getting things to the point where I was almost on the right track I turned my attention to getting the back side of the middle (chainplate) bulkhead vacuum bagged. I also found a left over piece of foam and applied a layer of glass on one side to serve as a test piece.

Some progress pics below:

First Template.
This one is used to mark the Solid Laminate areas at the clamp points

Clamp points shown

My apologies for a terrible blurry picture of the vacuum bagging

Test Panel being laid up for future use

The three templates that will be used for the entire operation.
I still had to make some modifications during my first test

Test piece of MDF to be used before trying again on the test foam panel

Initial cuts with a hole saw.
These were not removed here, but will be removed on the foam panels and back-filled (outer half) with Hi-Density Epoxy

Second Template accurately placed over the test piece and screwed in place for 7mm counter-sink around the outer edge.
This countersink will serve as the gasket sealing surface.

I had to increase the thickness of the template to account for the top bearing location on the router bit.
I also had to build a "ramp" from the router START location onto the actual work piece.

At this point, the "Pinch Points" would be back-filled with thickened epoxy and the gasket base would be prepared.
All I would need to do now is run a round-over bit around the outer edge before laying fabric over top and proceeding with either resin infusion of vacuum bagging. The center part would be cut out later followed by a layer of fabric around the deck plate perimeter to capture the raw edges (top and bottom)

7mm rebate

This gap will end up being slightly narrower once some fabric is laid in over the top.

The inner cut out is a bit ragged due to the difficulty of cutting MDF and also the fact that I'm cutting around the OUTSIDE of the pattern. I'll see how this works on the foam test panel and may create another pattern to allow cutting on the INSIDE of the template. For now I chose this method to keep any screws or other fastening methods away from "finished" work and only on the areas to be removed.

Final Install

Pretty smooth transition from deck surface to deck plate

Underside

Bulkhead weight loss

For whatever reason, I decided to log the weight loss of the starboard float forward bulkhead from unpacking to final trim. No real idea why - maybe just because I "could".

:)

Results below...

The final bulkhead to be built for this float is the center one which incorporates additional fabric layers for the chainplate and also a water tight access panel. Since I'd like to avoid fitting that access panel later on within the confines of the float I am going to attempt to get it done ahead of time before installing the bulkhead. To that end, I just got off the phone with Armstrong Nautical to place an order for a couple 10"x20" (254mm x 508mm) rectangle deck plates. I probably should have ordered some 8" (203mm) round ones as well for the tops of the floats, but those can wait for a while.

Once they arrive, I will work on figuring out the best way to get them installed.

At the moment, I'm thinking about a 1/2" (12mm) ring of Hi-Density foam installed around the perimeter of the opening where the gasket will seat and some Hi-Density epoxy at the four pinch points. I'm also thinking about recessing the foam so the deck plate sits flush with the surface of the bulkhead. That isn't really necessary, but I think it will be a good idea to work out the flush mount details before moving on to the more visible elements of the build (deck hardware, hatches & etc.)

I can't believe how useful the laser level is for this project.
The first thing I did was clean up the bulkhead location and mark the AFT edge with some tape straight edges.

Removing the Starboard Float forward bulkhead from the vacuum film.
This was a vacuum bagged piece, but the results are really quite nice.

Initial weigh in
This is straight out of the bag.
Peel ply removed but excess flange material still in place.

Excess flanges cut off (Rough cut)

Final trim completed

Marked and cut into halves with a small center strip removed as excess material

Beam position cut-out

Final weigh-in before gluing into float

A total loss of 701grams!
(That's 1.54lbs for some of us)

And glued in place with a narrow bead of thickened epoxy putty
(Total time invested was almost five hours)