Wednesday, June 28, 2017

Sunfish Coaming Rivets or Rivnuts

Update 28 Jun 17:

The Sunfish coaming or splashguard is held on to earlier models by machine screws and riveted nuts (rivnuts) or by rivets on later models. you can tell by whether there is a slotted screw head or a rivet head. Sometimes coamings come loose, leak, are broken or need to be removed for repair and restoration. Here is a Sunfish damaged by Hurricane Sandy, it has rivets that you can see in the coaming remnants and fractures around the deck holes where the rivets pulled out.

From Small Boat Restoration 2013

Here is a Sunfish that has clean rivet holes on the deck. The owner is cleaning up old silicone and a makeshift screw and wall anchor repair.

From Small Boat Restoration 2013

Rivets can be purchased from a Sunfish parts house like Yankee Boating Center and installed with a rivet gun, available from your local hardware store. The demonstration holes in this piece of particle board are 1/4 inch.

From Small Boat Restoration 2013

The rivet is inserted into the gun and then the barrel is placed though the coaming into the deck hole.

From Small Boat Restoration 2013

Squeeze the rivet fun handle, keeping rivet flush against surface. As the rivet shank is pulled the barrel will expand inside the hole. Continue to pull the shank until it snaps under pressure or will pull no further, gently rock rivet gun back and forth to shear top of shank if needed.

From Small Boat Restoration 2013

Here is comparison of a pulled rivet on the left vs new rivet. You can see how the barrel is shortened and expanded, filling the hole. It will expand below the deck on a Sunfish and anchor the coaming, the collar of the rivet holds on the top and the expanded barrel holds on the bottom.

From Small Boat Restoration 2013

This is what the rivet looks like on top of the hull and inside the hull.

From SBR 2013

From SBR 2013

1960 to mid 70s boats had closed end rivet nuts (rivnut) and 10-32 x 3/4 inch stainless steel machine screws to attach the coaming. The rivnut had a small bead of sealant that prevented water from leaking inside the hull.

From SBR 2013

Closed end rivnut seen from inside the hull.

From SBR 2013

If the screws are frozen, soak them with penetrating oil for a few days. Give them a few light taps with a screwdriver and hammer. Tighten slightly then back them out.

From SBR 2013

1st Gen splashguard.

2nd Gen coaming aka "The Mustache."

Tuesday, June 27, 2017

Alcort Standard Sailfish and Super Sailfish Handrails

We ran across someone looking for a handrail for their Super Sailfish MKII, the fiberglass version of the 13'7" wooden Super Sailfish. The handrails are a pretty important part of this boardboat, as there is not much to hold onto while sailing. Here are the rails on our SS MKII.

From Small Boat Restoration 2013

Most likely there are not a lot of spare Super Sailfish handrails laying around, so I offered to make a replacement. We measured the rail at 3/4 inches thickness, 41 inches long and 1 5/8 inches tall. Most likely the originals were mahogany, for this project I chose red oak, because that's what Lowes had in stock, ready to buy. I forgot to measure the height before I went to Lowes, so I guessed, as it turns out I can cut 2 rails from this 48 inch section that is "4" inches wide (actually measures 3 1/2"). There are host of other woods that could be used, in the future we might make a few from cypress or ash.

From Small Boat Restoration 2013

For this rail I took the oak out to our SS MKII and traced the profile with pencil onto the wood. Then I came inside and checked some basic dimensions with a caliper, like how wide the screw bases were, how high the rail stood and how tall the cutout areas were. The pencil tracing was off a little along the top, so I marked off 1 5/8 inches then redrew a straight line using a straight piece of wood as a guide.

From Small Boat Restoration 2013

I cut out the entire piece using a jigsaw. Next time I will use a table saw to cut the straight part of the top edge, that will make a straighter line. Remember your goggles and hearing protection.

From Small Boat Restoration 2013

Sanded the edges with a rando orbital sander, 120 grit to give them a nice smooth feel. Our edges are not as rounded as the 50 year old original, we left some room for them to age :) While I was sanding I decided to refinish the rails ou our SS MKII, they were pretty crunchy.

From Small Boat Restoration 2013

We used our rail as a template on where to drill the holes. When I drilled the holes, I put a scrap piece of oak under the new rail so that the drill bit would not blow out (tear out) the back side of the hole, couldn't show that here because I only had two hands. You can see the crusty patina on Sweetness' old handrail.

From Small Boat Restoration 2013

The original rails used a #10 bronze screw that was countersunk. I copied that with a 3/8 inch bit for the head of the screw and 5/32 inch bit for the threads. Next time I'll use a drill press, it was hard to control the exact depth I wanted by hand. Or skip the countersink. After holes were drilled we applied a coat of Minwax clear Polycrylic, it will protect the wood and let the grain show through. Polycrylic is water based and very easy to clean up.

From Small Boat Restoration 2013

The new handrail has shipped, and Sweetness has newly varnished handrails.

From Small Boat Restoration 2013

27 Jun 17:

Made some more handrails, made a set for the 11'7" Standard Sailfish as well, its handrails measure 28 inches. Used the pattern to set the table saw and cut the plank to height.

Traced the Standard Sailfish handrail profile with Winnie as the model.

Cut the ends. Rounded the top edges with a 3/8 inch roundover bit on my 30 year old Makita router.

Cut out the handholds.

Sanded the edges with 120 grit.

#10 bronze wood screw specs.

#10 Combination countersink and pilot bit.

Finished up with a set of Standard Sailfish handrails. Also made a pattern.

If you'd like to order a new handrail, click on the Paypal Buy Now link below. The handrails will be cut from rot resistant cypress and shipped without a finish, so you can finish as you like. Please select the appropriate handrail for your type Sailfish. The 11' 7" Standard Sailfish has a smaller handrail than the 13' 7" Super Sailfish series. Standard Sailfish handrails are 28 inches long and Super Sailfish handrails are approximately 41 inches long.

Sailfish ModelType

Wednesday, June 21, 2017

St. Jacques Log 21 Jun 17 Mast and Sprit

06 Jun 17:

Went and picked up some 14 foot spruce 2x4s for the mast and sprit. Cut them down so we had 2 pieces, one set to make a 2 1/2 inch blank for the mast and one set to make a 1 3/4 inch blank for the sprit. The mast is 11' 7" and the sprit will be 12'3".

Left them long so we can pick the best section after they are glued up. Fastened them together with Jamestown Distributors TotalBoat THIXO thickened epoxy.

09 Jun 17:

Took the clamps off the spars. Marked the circumference on the end. Cut 45 degree angles on each edge just outside of the mark with the table saw. Now they are 8 sided.

(Edit: Stop. That circle is required 2 1/2 inches. No room to spare. So at this point we needed to cut the corner bevels perfect AND turn the blank exactly from the center in order to maintain that diameter. Stay tuned).

Eight sided the spars. (Edit: We should have marked center before eight siding, it was hard to mark afterwards as our bevels were not all equal. The result was us finding the wrong center for turning the spar and as a result the diameter was less than desired.)

21 Jun 17:

Built a shaping jig for the spars and router sled. Main box was made from 2x6 lumber with 1x6 ends and 1x6 feet. One end can be moved to accommodate different length spars. Drilled a 7/16th inch hole in the spar ends and inserted dowels. We cut the mast side profile on 2 lengths of 1x6 lumber and screwed those to the box, just proud of the box, that is what the router sled will slide along, guiding the router up and down in order to get the desired diameter. There was a little experimentation to see how high to place those taper patterns, too high and the router bit wouldn't cut as deep as needed, too low and the excess wood on the blank would bump against the bottom of the sled. The router sled was made from 2x6 guides and a 1/4 inch plywood base plate. A thicker base plate, maybe 1/2 inch, would have been better as that base plate would deflect down a bit with excess pressure and we had to watch that. The router is a DeWALT compact trim router with a Bosch 3/8 inch flush bit.

In theory we would have been able to set the router to just barely touch a flat on the blank, then turn the blank and get a nice even circle cut evenly all the way around. In practice we found our 8 sided blank was a little lopsided and the dowel hole was a bit off center, so we cut more off of one side than the other. We adjusted by cutting a little deeper on one side, which resulted in a spar diameter around 2 1/4 inches the design 2 1/2 inches. It seems very strong irregardless, and based on our experience that we have carried similar square footage on a Sunfish wooden mast that was 2 inches in diameter, we will give this mast a try and see how it does. This issue became even more evident on the sprit, which we had cut to exactly 1 3/4 inches. Two attempts to cut an exact round spar out of the blank were unsuccessful. What we will do to fix that is be more precise on eight siding the spar and start with a bigger blank.

Note how the inner 1x6 guide tapers down at the far end to allow a deeper cut. Both ends are tapered per design.

We could hold the sled in one spot and turn the blank by hand to cut a groove, or we also held the spar still and moved the sled to cut one aris. Just depended on what mood we were in. We checked the diameter with calipers. In some areas the rotating blade of the router would catch small bits of the blank and start it turning like a lathe. That would have been great to do the whole spar that way but the blank was out of round and the jig bounced around.

Nice views of the tapered ends and profile templates.

This idea came from a youtube video on how to turn a cylinder from the Woodworkers Guild of America. We scaled it up but did not make the bottom of the box solid, that way sawdust could fall to the deck and we swept it up later. We also used dowels in the ends vs the hardware that they used. After trying a few blanks, we might go get the hardware to hold the ends similar to what they used.

Once the mast was rough cut we took the belt sander with 40 grit and lightly ran it perpendicular to the mast. The mast would rotate, fast if we let it, but we could control the speed by slowing the mast with a gloved hand or by varying the angle and pressure that we held the sander. Parallel to the mast = no rotation. 90 degrees to the mast, lots of rotation. We also sanded some areas along the grain and rotated the mast a few degrees at a time to shape areas around the tapers. Final sanding was by hand with 120 grit.

Mast was sealed with Jamestown Distributors TotalBoat Wood Sealer. Then lightly sanded with 120 grit. Then we applied TotalBoat Gleam Marine Varnish Satin. Repeat sanding and varnish times 2. The wood sealer is great, it makes a nice base for the varnish and it does not seem like we have to build as many coats of varnish. We prefer the satin finish over high gloss. We also like the varnish kit that Jamestown Distributors provides with the quart kit, it includes 2 paint pots, 2 stir sticks, 2 foam brushes, 2 paint strainers, and a pair of latex gloves FREE.

This is the mast after we sanded the wood sealer, ready for the first coat of varnish. Wiped down before varnish was applied. A light sanding between coats creates a better surface tooth for the varnish to grip and it is easy to see where the shiny varnish is covering the scuffed areas.

3rd coat of varnish.

Log of St. Jacques.