Stern chainplate angle?

[Ben Coombs]

I am switching to an external chainplate for the rear stay on our CD25. The rebar that was glassed in had about 1/4" of good steel left holding the rig together. We were an accidental gibe away from an exciting time.

I am fabricating my own chainplate and wondering how to calculate a proper bend so the stay matches up to the tang of the plate. So far my best method is to use a protractor on a printed out profile of the rigged boat. Also, since the new connection will be aft of the original, I also plan to make it slightly higher to accommodate the arc of the "swing" that the stay will take to meet the new plate.

...or if someone has already done this and wants to just tell me correct angle, that would work too.

Fair winds.
ben

[hilbert]

Trigonometry should get you close enough. The angle on a CD28 is approximately 45 degrees.
I used the main halyard to support the mast, while I checked and made some fine adjustments.

[Steve Laume]

There must be another CD25 somewhere near you. It would be a good chance to meet another CDer and you could get a very accurate measurement. The owners guide should fine you someone. Even up there in Maine there should be a bunch of boats rigged by now, Steve

[Ben Coombs]

Thanks for the suggestions... but it’s already done.

As it turns out, the need to get the job done outweighed the time to wait for a response. I realized that would be the case shortly after my question was posted.

I couldn’t locate my protractor, so I used a ruler to trace the angle off the profile plan in my owners manual—I have the original. Then I cut that out to use as a template for bending.

Installing was interesting though... I didn’t calculate the distance correctly for the top hole of the new chainplate. When I drilled the hole it ran through the stern toe rail. So now the top boot actually is holding the deck down as well.:.. so that’s good, I suppose.

Here are some photos of the new stern. It stopped me at three, so it will take another post. Thanks for the suggestions though. This board is always active. Good stuff.

[Ben Coombs]

Two more pics... plus one of my newly buffed and waxed cabin. That’s just for fun.

[mgphl52]

Nice job!