Previous entries: Day-1, Day-2.
The first step today was removing the clamps and masking tape from the "big crack" repair. A bit of work with the in-line sander followed by a few passes with the DA cleaned up the excess epoxy nicely. The joint looks good, and the sideboard is back mostly in one piece!
There look to be three areas that will require vacuum infusion of epoxy. Some small cracks forward, the multiple cracks at the knee, and where the "big crack" exits through the aft end of the grab-rail. It's been awhile since the last time I fixed a crack with the vacuum, so I decided to start with the relatively simple (and isolated) cracks at the aft end of the cockpit.
The first step was to establish the extent of the crack, so I could decide how much to cover with the plastic. Then I cut a chunk of polyester batting and plastic sheet to cover the area. With the batting in place, I taped around the edges of the plastic with duct tape:
After running the vacuum to check the seal (I could feel air being drawn into the larger part of the crack), it was time to mix up some epoxy. I was a bit concerned that the narrower parts of the crack wouldn't get good "suckage" with the air flowing through the wider areas, but it didn't seem to be a problem. As evidence, there was one section of crack that was on a vertical surface and epoxy running down the surface was completely pulled into the crack by the vacuum. As with any glue-joint, I started with neat epoxy and then added some cotton to thicken it. I actually did two passes of thickening, starting with a thin mix and finishing up with some thicker just to make sure there was filler in as much of the crack as possible.
With the crack filled with epoxy, I turned off the vacuum and removed the plastic and batting, checking to make sure there was epoxy evident along the entire length of the crack. A bunch of clamps pulled everything together. I checked that there was epoxy oozing out everywhere before heading home.
Tomorrow I plan to infuse the large area of cracking near the knee and probably cut the piece to fill the hole in the bow. Jim Nordhaus was kind enough to loan me the plank attachment plates and steering chock from the box of parts slated for his "under construction" DN project (Thanks Jim!), so I think I have everything I need in-hand to complete the repair.
Three more hours on the project, for a total of 12...