Hunter 212 mast step cracked again

[JT_Fulkerson]

I purchased a Hunter 212 with a large crack from the hatch through the mast step. I was able to get the mast step pieces repaired, and I used Plexus MA300 to repair all the cracks. I read that besides a little cleaning, no surface prep was necessary and the temperature was goods Took it out last week for the first time, and had a great sail, but while de-stepping the mast, the same crack reappeared. I am attaching photos, but would love any advice on what went wrong. I expected the repair to be stronger than before so surprised it cracked again.

 

[Don S/V ILLusion]

The Plexus with which I am familiar is a cleaner so not sure what you used.

 

[Don S/V ILLusion]

I see you modified your post to be more specific regarding the adhesive you used. Hope that helps.

 

[rgranger]

When seeing that crack, my first thought is that you have some flexing going on. Is your deck plate through bolted? If so, is your backing plate sufficient? Are you stays properly tunned?

 

[JT_Fulkerson]

@rgranger thank you for your reply. I had to modify the mast step as the bolts had seized inside of the posts. I struggled to get an exact replica made, so I took off the posts and used some aluminum pieces as extra structure and planned to waterjet out a bigger backing plate to help spread out the load. On that first sail I did not put on the bigger backing plate as I was just trying to see if the crack would hold up... I will create that bigger backing plate and install it this week. When fixing the crack again, do you think it would be beneficial to use some fiberglass to reinforce?

 

[rgranger]

Maybe grind them out a little with a dremmel and then fill it in with some JB-Weld or epoxy putty.

 

[Project_Mayhem]

Maybe grind out a wide V around the crack, use some fiberglass cloth/mat soaked in plexus, maybe some more plexus on top of that and then sand it to look nice. If I remember correctly, some of the JY15's and Hunters had a plastic material that most resins and adhesives wont bond to. I know someone who owns a JY that had a ton of cracks. He fixed it with Plexus and named it Humpty Dumpty