Rudder Gudgeon Plan

I spent a bit of focused time thinking through the rudder gudgeon installation. This is going to get detailed.  There are two main issues I see with these. The first is that they have to be installed in a way that does not introduce a leak path through the transom. The second is alignments, they need to be aligned with the rudder housing to insure that the rudders can rotate about their pins (no binding) and be offset so as to fit the rudder housing.  So here is the procedure.

1. Make a jig to using a rod to hold gudgeon pin axes aligned, a lip to locate transom top edge, and a mark to locate center.

2. Cut and install 9mm plywood backing on inside of transom

3. Locate jig on transom and drill pilot holes

4. Drill out pilots to large hole and fill holes with filled epoxy

5. Re drill pilot holes using jig

6. Drill 3/8 clearance holes following pilot holes

7. Drill T-Nut depth counterbores on inside of transom

8. Install T-Nuts with filled epoxy and polymer brad nails

9. When installing gudgeons use bedding compound

It should end up looking like this.

There is a risk that some filled epoxy could get in the threads of the T-Nut, That can be chased out with a tap after it cures. Now for the good part. When building the rudder housings do the following

1. Use jig to drill pilot holes in scrap plywood.

2. Use pilot holes and alignment rod to temporarily install gudgeons on plywood.

3. Use this gudgeon installation as fixture to build rudder housings.

By using the jig and rod to set up both the gudgeon installation on the transom and the rudder housing build. I (hopefully) will avoid any part fitting or binding issues. I like this procedure because while there are seemingly many steps, each is very simple.