Rebuilding the Aquasport Classic "flatback"
We put in the first 2 layers of inside transom skin. First layer is 1708, second is DB1700. The inside skin will be 4 layers total of 17 oz. Biaxial glass. The first layer has mat (1708) because the mat helps conform to any uneven spots in the fillet. Subsequent layers will not have mat as it will just use more epoxy and not add strength.
I worked "wet on wet" for the fillets and the first two layers of glass. Using a mix of silica/woodflour and epoxy, the gaps along the sides and bottom of the core had been filled so the filler was level with the core. Using the same mix, we laid fillets along the joint. This fillet is about ½" radius.
After 15 minutes or so, the fillet is firm but not hard. At this point we lay in the pre-wet 1708. Because the fillet is not hard, you will be able to push the glass into the fillet making for a very clean lamination – no air bubbles. A second layer of DB1700 was wet out on top of the 1708. DB1700 (17 oz. without mat) wets out much easier than 1708, so you can do it on the part – no need to wet out the back side before placing it.
All the inside layers will be overlapped by 3"-4" working up the hull. Working wet on wet saves time and makes for better laminations. In this case we should have gone ahead with the last 2 layers, but time did not permit.
Transom is complete!
Have spent the last couple of days grinding out a path for the new stringers. Unfortunately it was not just a matter of cleaning a path, but removing 2 layer of roving and matt. Even with a 24 grit grinding disk it took 6 hours total. Results are a clean path for the bond of the new stringers and about 40 pounds of fiberglass dust in the trash can.
Now I can start taking some measurements for the stringers. I sure wish I could find someone who could give me some measurements of the original sole height...
That PVC pipe is a stiffener put in by the previous rebuilder - I'm leaving it in until I get the new stringers in. Then it comes out and a new center stringer goes in.
If you take all the internal supports out of the hull at once it will deform. That is why we left the gunnel cap and a lip of the sole - it holds things in shape.
