|Work space or refugee camp? Attempting to keep things dry.|
When we left off there were a couple days of unsettled weather that arrived. After the storm that hit at the end of the last post, we mopped up the mess and tried to get everything dried out. They called for 70% chance of rain most of the following day and that usually means we will get soaked (water and laying fiberglass just don't mix). So we did some shopping and other preparation while we waited on the weather...that never came. The ominous looking clouds finally just fizzled out about 3 PM. We cut the two smaller pieces of foam that need to be glued to the ends of the 8 foot panels so we end up with 9.5 foot panels and punched holes in them, but that was it.
The next day the forecast was similar, but we decided we wouldn't be fooled again. This project was already taking a lot longer than I had hoped, so we didn't want to sit around waiting for weather that may not arrive. We pulled out the two remaining foam panels and spent the day punching holes in them. The 9 nails in the tool make this a much longer process than I would like, but it does work. Well, until a nail breaks off. You see, you tend to bend the nails after pushing them into the foam so you have to constantly straighten them. Eventually the bending weakens the nails and...well...you end up digging one of them out of the foam panel with pliers. Good thing I had the remaining piece of the original longer board full of nails so I could just cut another 9 out of it and finish up. Again, thankfully the rain never came.
|Gluing the extensions on the large panels.|
Then it was time to start gluing the remaining panels together. Since I don't have a full mold and only stringers, I had to attach the two side panels to the mold so the end would lay over one of the stringers and then glue the small pieces to them. This would keep them properly aligned and holding the curve. Using polyester resin that I reinforced with some chopped glass fiber and fumed silica, I created what I could only describe as "hairy polyester mud" to glue them together. I smeared the concoction into the joint, then pushed the smaller piece into position and held them in place with sandbags covered in plastic. I used a plastic spreader to remove the excess that squeezed out in order to minimize later sanding. It is much easier to scrape off wet goo than sand down hardened polyester.
After the two side panels cured, it was time to adhere them to the center panel. Now one might think that the edges of a 4 foot by 8 foot foam panel would be straight, but they did not line up with the center panel very well. I discovered that the center panel had pulled up from the mold a bit, I assume from the shrinkage of the polyester. It seems that the 30 lb. test fishing line I was using stretched or the knots slipped a bit. I was able to pull it back down with some wedges between the frame and the line. This shrinkage may have given the center panel a slight curve along the edge as well. so I then had to sand the panels a bit to get a better fit.
|Panels tied to the frame and glued together.|
Once the fit was better, I used a similar concoction to glue the side panels to the middle panel. We tied the edges that are closer to the seam to the mold so we could slide the panel back a couple of inches. I also threaded ties for the other side through the panel but left them untied so we could move it. By sliding the panels apart a couple inches, I was able to apply the hairy mud from underneath the mold. We slid the panel into position, checked the alignment, and tied the free end down to the frame. Since there was one spot on each panel that didn't line up flush, I used boards wedged underneath the mold to hold them even.
|All the panels are attached. This thing is getting big.|
When all of that cured, we had a foam panel roughly the size of the final top with a fiberglass strip down the center. All that was left was to finish shaping the foam construct so it would be the final shape of the top and ready for glass. Using a razor knife, I roughly carved the back edge of the two new panels and then sanded them so they matched the needed curve for the mounting flange. In order to protect the back edge of the mold, I slipped a sacrificial piece of heavy plastic between the foam and the mold and adjusted its position when sanding would start cutting through it. This worked well and allowed me to get the curve to match up very well with the mold.
|Rough cutting and then shaping the back edge.|
The final step was to cut the curve at the front. I used the trick I originally figured out for creating the curves on the stringers. Taking a boat stand, some line, and a pencil, I created a crude compass to draw the arc. In this case I didn't have a radius (for some reason, SketchUp wouldn't tell me the radius) but I had the intersection points on the edges and the length at the center, so I figured it out where to place the boat stand (a.k.a. the compass pivot) using trial and error. I then cut the curve using my jig saw fitted with a fine tooth (32 teeth per inch) metal cutting blade. Where the foam intersected one of the mold stringers, I switched from the saw to the razor knife to keep from damaging the form.
|Scribing the arc with a boat stand and string again.|
A little sanding and it is now ready for applying the remaining fiberglass on the top side. If the weather continues to cooperate, that will likely be what we will start tomorrow.