Mast Tubes and mast steps

1-9-15  Mast Tubes
While waiting for the actual shipment of the aluminum tubes for the masts, I got antsy and went ahead and purchased a 3 chunk of 2.5 OD Aluminum of the 6061 variety used for the actual masts.  This will serve as the mandril to form the mast tube(s) for the mast support(s).  The plans call for one tube about 22" long in the bow for the main mast, however I am building tubes for the mizzen at the normal location, and a short tube to be put in the step to the seat deck level at the alternate mast step location.

Step one - place 1" vertical strips of 6mil plastic along the mandril.  These will serve to help release the actual tube from the mandril.

Step two - place 4 layers of 6 mil plastic around the mandril to provide some clearance for the actual mast.  Not too tight, not too loose a fit.

Step three - wind 2X4 of 10 oz fiberglass around the tube while wetting it out with epoxy.  It took me an hour to wet the glass out.

The music stands worked pretty good as work supports.  I rotated the mandril a little at a time while wetting out about 2" of fiberglass.  

Clean up took a while, but was glad I put plastic tarps around everything.  

Step 4 - 6 hours later, I removed one of the 1" strips from the tube and the whole thing started spinning freely.  So, I slid the assembly off the mandril and twisted the plastic sheeting out of the tube.  Then trimmed the loose stuff off with  razor blade.  So far, this was one of the easier aspects of building this boat!  Will make two others for the other mast and alternate position.  

completed mast tube.
The center thwart had one screw in the way of the mast hole!  Fortunately, it came right out with the frearson head screw bit #2.  

The tubes measure an OD of 2.803.  That is more than 2 3/4" but less than 3".  No one has a 2 7/8" hole saw, so had to order one.  Yes, I could have used the saber saw, but the hole saw will be much neater.  

1-15-15
Turned out that finding a 2 7/8 hole saw was harder than I thought, but my local Woodcraft store had a 2 7/8 Forstner bit in stock.  Took it home and realized it would not fit into the chuck of my handymans drill.  Therefore, borrowed a friends 1/2" Heavy duty drill to do the honors.  The first step is to make a guide from spare stock which will help keep the bit on track as it initially grabs the wood.  
2 7/8" hole drilled into a spare piece of 3/8" stock.  small sliver of trimmed mast ring is sitting in the hole to check for proper size.  Looks good.  
So far, so good.  will drill the bow and thwart holes in the morning.  
I will not be putting the alternate mast step in as I really dont want holes up in the cockpit.  With two reefs in the main and mizzen, it should be fine.  

1-16-15
Mast holes located and drilled.  
1.  Mark location with a punch and set drill and 1/4" template in place.  
2.  Drill out! 
3.  Use a curved rasp and drum sander to finish mizzen hole.  The 1 1/2" centerboard frame needs to be cut and the Forstner bit will not cut it properly.  (note:  I could have attached a small board under the thwart to help steer the bit, but thought of that too late in the process.  No harm done.)  I will be purchasing a set of microplanes for this kind of thing in the future.  

Voila! 

The bubble level shows that I have it set vertically at the moment.  Needs a 3 degree tilt. 

Mizzen step.  Test for fit.  Drain hole needs to be drilled for the step.  

There is plenty of play to adjust the angles, fore and aft, port to starboard.  A 2.5" mailing tube fits perfectly!


A little router work and the deck is cut away for the tube.  Deck wont be fastened until hatch and tubes are glued in place, plus combing needs to be cut to fit as well.  Poco a poco. 








March 1, 2015

Finally gave up waiting for the winter from hell to end.  For those reading this from afar, we have had over 100" of snow in 30 days, and we have had one day where the thermometer made it above freezing.  Just horrid boatbuilding weather.

Today, I took stock of the mast tubes from B+B and looked at the track and sails I ordered as well.  this inspired me to go out and set the boat level and get the mizzen step aligned.  It did take well over 2 hours to get the boat level with the bow 10" higher than the stern, but I believe it is good.  Will take a good look at all prior to screwing the mizzen step down to the keel batten.  Also took time to make the seat/floorboard supports look good.

This weather is going to break soon, and then the project will pick up speed.  Right now, just moving in the cold is the project.

mizzen step is marked, not glued


Major delays due to this stuff!  WAAYY too much snow this month, and COOOLLLLDDDD. 


Forward hatch frame being fitted.  no glue yet. 

3-12-15
the mizzen step has been glued and screwed in.  Sorry no photos as I needed to move FAST due to the amount of work to get done on the only warm day since October.  

At the top of the step, you can see the drain hole. 

Forstner bit was used to drill the thwart.  This was not easy as the CB trunk is in the way of the cut. 

March 27, 2015 
Finally got sick of the longest, coldest, snowiest winter on record for the Northeast US, and turned the heat lamps on in the boat and epoxied up the first layer of support for the mast tubes.  This locks the tubes in place permanently.  I angled them with a 20" level and a 1" block of wood attached with tape to the level.  Seems pretty straight.  Now the boat which had been leveled can be moved around again and I can get at some other stuff in the garage.  Hope to get it out in the daylight for cleaning next week.  It cant be winter forever.  

March 28th - Heaters on, and mast tubes glues in place. 
I ran out of patience waiting for it to warm up outside, so went and placed heat lamps in the boat to warm the areas getting epoxied and keep warm while it sets.  The lower sections of the masts were inserted into the tubes, and then the level placed on the forward side to measure a 1:20" angle by placing a 1" block 20" up on the level.  The sides were set plumb, then a visual by checking that the main mast and mizzen were on plane for and aft.  Unfortunately, I cannot do a side visual within the garage.  Photos below. 







The whole assembly can now be moved around without fear of knocking things out of alignment.  I will add Fiberglass tape to the areas tomorrow to create a beefy, permanent, attachment to the hull.  




March 29, 2015
Glassed the base and below deck portions of the mast tubes and made the holes for the alternate position for the mizzen.  Thinking that the rowing position is better with the mast temporarily moved up, and that I have have a better area for camping in the long run.  
alternate mizzen step.  Pretty easy to do after you have done the mizzen and main tubes.  No tube needed as the deck and seating area will hold the mizzen in place firmly.  I will use a slice of extra mast tube to serve as a bushing at the deck level.  

mizzen step.  Will trim flush once the epoxy sets up. 

Main mast glassed in place and filleted with high strength filler. Drain tube needs to be added next.  

Better view of the mizzen step glassed in place.  Heat lamps are helping to kick off the glue.
Some more photos.
Alternate mizzen position.  Not much bother to put in. 

Cleaned boat ready to move on to some finish and trim work prior to putting the decks on permanently.

Center thwart with mizzen tube.  Some fairing and sanding is needed on the bottom step.

April 12, 2015
Mast tubes are all glued in place and the drainage tube installed from the bottom to the starboard forward quarter.  I used 1/4" drip irrigation tubing covered in cork grease for the mold and ran it through a 1/2" hold on the starboard quarter.  The thinking is that the plywood will be sealed by the epoxy filler.  Good in theory, but epoxy did not get into the bottom 1/2 of the exterior hole so will need to fill it from the outside.  The main tube could use a little more reinforcement, so will add a little more glass to the step prior to putting the deck on.  

this runs right from the bottom of the tube to a little below the mast step.  

A little sanding and painting and I am done with the mast tube drain.  Boat needs sanding anyways!

Related Posts by Categories

0 comments:

Post a Comment