lenmann
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Stress cracks in the deck forward of the dash above the bulkhead are pretty common in older Schiadas. The early RC’s had a "U" shaped bulkhead forward of the dash and used ¼ inch balsa coring to support the deck. The bulkhead to deck interface was glass tabbing to the balsa creating a high stress area on the deck as it transitions up to the dash and at the center of the “peak” in the middle of the deck. As the boat pounds through rough water the deck flexes around the bulkhead and causes the cracks. Well, the ski racing or some other activity (disco dance parties?) took its toll on this deck resulting in the laminate yielding under force and “folding” around the ¾ inch thick plywood bulkhead distorting the deck in addition to the usual stress cracks.
After I tore the original carpet off the bulkhead I could see it had actually fractured from the pounding the boat took. Even though it had structurally failed it was still partially supporting the deck.
When I cut the bulkhead out the deck dropped causing the deck to lose it original shape. I made a template of what I thought the curve should be based on the forward deck and my best guess of what looked right. I was down in the LA area off-roading at Dove Springs and Stan at Schiada was gracious enough to let me test the template on a new RC and my guess was dead on. Now to figure out how to restore the shape to the deck and provide better support than the original configuration had.
New Schiadas have additional deck coring, a structural profile that runs side to side, and a plywood pad on top of the bulkhead to spread the deck loads better.
I have seen a handful of older RC’s that have had bulkheads replaced and they often have a more complete profile vs. the original U shape. Additionally I have seen a couple that have been fitted with a second bulkhead forward of the original to help support the correct shape of the deck after the original bulkhead didn’t some 40 years later. This is the way I decided to go.
Using a scissor jack I lifted the deck up into its original shape, hot glued a template of Masonite (the way the granite guys do countertops), cut the bulkhead, shaped the edges to match the taper of the hull and provide clearance for a ¼” thick trapeziodal shaped Divynlcell filler between the plywood and the hull to eliminate any hard contacts that might create future stress cracks and create an easy transition for the glass tabbing. Once everything was adjusted into the right shape I used 6” wide 1708 tape to tab the bulkhead into place.
After I tore the original carpet off the bulkhead I could see it had actually fractured from the pounding the boat took. Even though it had structurally failed it was still partially supporting the deck.
When I cut the bulkhead out the deck dropped causing the deck to lose it original shape. I made a template of what I thought the curve should be based on the forward deck and my best guess of what looked right. I was down in the LA area off-roading at Dove Springs and Stan at Schiada was gracious enough to let me test the template on a new RC and my guess was dead on. Now to figure out how to restore the shape to the deck and provide better support than the original configuration had.
New Schiadas have additional deck coring, a structural profile that runs side to side, and a plywood pad on top of the bulkhead to spread the deck loads better.
I have seen a handful of older RC’s that have had bulkheads replaced and they often have a more complete profile vs. the original U shape. Additionally I have seen a couple that have been fitted with a second bulkhead forward of the original to help support the correct shape of the deck after the original bulkhead didn’t some 40 years later. This is the way I decided to go.
Using a scissor jack I lifted the deck up into its original shape, hot glued a template of Masonite (the way the granite guys do countertops), cut the bulkhead, shaped the edges to match the taper of the hull and provide clearance for a ¼” thick trapeziodal shaped Divynlcell filler between the plywood and the hull to eliminate any hard contacts that might create future stress cracks and create an easy transition for the glass tabbing. Once everything was adjusted into the right shape I used 6” wide 1708 tape to tab the bulkhead into place.