Masts

I ordered the mast tubes from B+B yacht design.  They come in 8 sections, with the two lower sections being reamed out for a perfect fit.  The upper sections need to be fit with a fiberglass bushing.  This is pretty easy to make from 3" tape cut in half and made 29" long.  After the bushings set up, sanding them down to fit is relatively easy as the masts make dark marks where they are fitting tightly.  Took an hour to sand and fit.

The only puzzle is the placement for the nutserts for the mizzen sprit on the purchased spar section.  The mizzen nutserts are sitting almost a foot higher than on the mark indicated on the plans.  I hope to figure out if this is a modification from the plans, or if I need to put Nutserts at the plan lines.

The main mast looks great.  I will add the stop collars to each section tomorrow, and then glue them all up this week after doing careful alignement.

5-25-15

I put the stop collars on yesterday, and confirmed that the snotter placement on the mizzen is correct.  New sheet had error on that line, old sheet was correct.  

June 9 - update,  fiberglass mast track wedges

Each section needs to transition smoothly from diameter to diameter.  I used Alan Stewarts method for making fiberglass wedges for the sail track.  I also applied a little filler over the mast collars and sanded so as to blend in with the ramps.  This was not a difficult job to do.  

• cut 3" fiberglass tape in half to make 1.5" strips
• cut 14" length, then 13", 12", 11", 10.
• place on a piece of plywood covered in packing tape and epoxy up the wedge. 
• apply packing tape to each diameter section of the mast at least 6" longer than the wedge
• move wedge to mast and press in place. 
• After it sets,  remove from mast, clean up, and cut in half to make two wedges from each strip
• Clean up packing tape and masts with a quick wipe of acetone.  
• place in place, epoxy, and fair in place.  

Fiberglass mast track wedge epoxied in place. 

Photo distorts, but it really is a straight line in the transitions.

filler over the collar transitions to the fiberglass ramp.  

June 9, 2015 - rivets

I have decided to join the sail track to the masts with stainless steel 5/32" rivets with stainless mandrels.  To isolate from the aluminum mast, I am applying anti-sieze lubricant, and plan to epoxy  coat the mast and paint it prior to installing the track.  

June 18 - assembly - mast tracks

Attaching the stainless track to the mast is a chore as I do not have a long handled rivet gun.  Setting stainless steel rivets involves strength and determination as well as careful alignment of the tracks.  

I go the rivets from FAstenal,  great selection, price, and service.  I have a pile of 5/32nd stainless rivets with stainless mandrels,  I am using some plastic tubing (wands from shop vac) as handle extensions to get enough leverage to set the rivet.  Every now and then a mandrel falls into the mast, or the mandrel breaks off at the wrong point and rivet removal becomes necessary.  I broke one drill bit already.  Proud to report that both sails move smoothly along the track!  

Just because I could. 

test of track.  The joint needs to be very level to avoid binding.  A few short raps with a hardwood block worked.  The ends did not need to meet exactly at 90 degrees as the plane of the rails had more effect than lateral alignment on smooth operation.

Related Posts by Categories