BRS17 Blues

[robertnc28]

The mizzen mast step on my BRS-17 failed tearing up the seat.  Looks like the strep plywood laminate failed, possible due to water damage since the step wasn’t epoxy coated (not sure about about whether the step should have been coated - I’m not the builder).  Looks like the mizzen mast step is built up from 3 pieces of 3/8” plywood.  Could use some suggestions on how to repair the step and seat.  Thinking of making a new step, plane and sand out the old step, and epoxy the new step in taking care to epoxy coat all surfaces and possibly add a piece of fiberglass inside the step.  Not sure if the mast step should be epoxied to the centerboard trunk (appears the old step was barely attached to the trunk - maybe by accident).  For the seat, thinking of glueing the seat back together and add a piece of plywood underneath the seat to re-enforce the seat repair.  Thoughts?

 

In addition, the mizzen rope traveler pulled out where it was just screwed to the rear seat.  I’ll just re-attach the mizzen traveler using backing plates.  Any suggestions on where to attach the mizzen traveler where the motor on the transom will not interfere?

 

 

[Don Silsbe]

I have a BRS15.  My mast step is similar to this, in that it is made up of layers of plywood.  I did make sure that it got a couple of coats of epoxy.  Also, I have a drain hole in the bottom.  If it gets rain water, it does not accumulate. Also, my mizzen sheeting is like the plans.  I tried the setup you have, and it wasn’t worth the effort.  (The mizzen doesn’t require the care and attention that the main does.).   I don’t know of any method to keep the mizzen sheet from hanging up on the motor.  Maybe a boomkin is the solution.  That’s what Graham did on his CS 17 mk3.

[robertnc28]

There was an approx 1/4l” weep hole in the step facing the stern.  That’s right where mast step broke in two.  Good to know about epoxy coating the step.  I believe lack of the epoxy coating cause the plywood in the step to delaminate over time due to moisure.

Thanks, Robert

[Designer]

Hi Robert,

 

I can see what happened. The mast step broke out on  port tack, with the mast falling over to starboard and levering up the thwart on the port side. 

 

The first thing that I would do is to check around the mast step for rot. I use a dull blade without a sharp point (you can poke a sharp point into perfectly good wood)  and poke the sound wood just hard enough to not hurt it. Then use the same force on the suspect wood. If the blade does not dive into the wood it is probably okay.

 

Over the years we have made that mast step longer and wider and widening the keel batten on the port side by way of the mast step to give a bigger connection and margin of safety especially as we had no control of the build quality. There was also supposed to be four screws thru the step down into the keel batten.

 

If the thwart is sound and you want to be the least invasive, you could make two skilsaw cuts parallel to and by the mast hole to the port side to cur away all of that splintered wood. Fit and epoxy in a new piece. Or you could just cut out the old thwart and fit in a new one. 

 

Without seeing the rest of the boat it all looks like a very simple job. If you need any help don't hesitate to ask. 

 

We do not use a traveler on the sheets because the sprits act as traveler's.

 

There has been much discussion on this forum on a non fouling mizzen mizzen sheet.

 

 

 

 

[robertnc28]

Graham, thanks for your update.  You are correct on the failure.  

 

Cutting out the splintered part of the thwart will greatly simplify the thwart repair.  I will add a 2nd wider strip to the bottom of the repair strip for more strength in that repair joint.

 

Can I make the new step wider than the keel batten for more strength?  But just adhere the new step to only the keel batten and not boat bottom panel?  What about adding a piece of fiberglass in the step to distribute the shear force load in the step?  Of course, there will be still a need for a drain hole in the aft part of the new step.

 

Robert 

Beaufort NC

[Designer]

Yes you can but you need to add a piece of wood to to tie it together. See the red piece in the 2d drawing of the mast step.

 

 

[Gira Gira]

Hi Robert, this is what I use to minimise the mizzen sheet fouling the motor. It’s electrical conduit with dyneema running through the middle.

The main sheet system is a “German” sheet set up the sheet runs back to the mizzen mast then down to the thwart.

it mostly works well.

Cheers John

[robertnc28]

Graham - appreciate the drawing

 

John - I remember seeing your “german” sheet.  I find it interesting that you attach the sheet to the transom.  That opens up some possibilities.