I kept pondering on this and really want to try to fix the rower frame. I knew that just gluing it together would not work. The thoughts of having to chisel out the dados to replace the broken cross piece was not appealing, at all.
Then I had the thought, I could add a cross piece making the cross brace into a T shape. That would make the whole frame much stronger I couldn't just glue it on top because thew wood was oiled and glue wouldn't stick. Secondly it would be in the way for the sliding seat hardware so I need to mill a dado and cut down the broken piece too.
Thinking on how I was going to this I leaned toward making a router jig, but I kept thinking how much faster a dado stack on the table saw would be. Problem was, I was certain it wouldn't fit on the table.
I was right, it wouldn't fit but I discovered if I removed the left side extension on the table it would. It was going hit the fence rail at the back but there was just enough space to finish the cut. So I removed the extension. Clamped some scrap the miter gauge and clamped the broken frame together so it couldn't move.
I am not quite finished with the cut in this photo. I cut it 1-1/2" wide and centered on the cross brace. By doing this I cut off the top of the broken brace that was oiled. Now I have clean wood across the top to glue too.
I decided I had better add a second piece further back to help prevent any racking. When I slid it over to make the cut it really wanted to tip over without the extension table in place. I didn't want to replace extension just yet so I grabbed one of the big cast iron clamps and placed it on the end as a counterweight to help balance it. Then I clamped it to the miter gauge and that worked.
Here is the finished unit. It's now much stronger. I have installed heel cups, added a temporary foot strap (I think I want some wider webbing) and installed the rails and seat.
Here she is, all finished as far as I can tell. All I need to do is check the transom to make sure it is water tight. I don't expect a problem but I would rather find it now. If there are no surprises then she is ready for the water.
We are in the middle of a heat wave so I am not sure when I will be on the water. I have been working on the rowing machine at the gym and I know that rowing can be a strenuous workout, so I may have to go by myself early one morning.