Monday, August 15

The start of our last week. Geoff began the day with a few tidbits. He reminded us that the parts we began making (rudder, centerboard, etc.) should be store flat; they will warp despite relative thickness. Scarf cleanup was reviewed: heat gun plus scraper followed by 60 grit sandpaper. Then, talking about planking, Geoff demonstrated that if a batten seemed unfair, you can measure the plank at that point and take the corresponding measurement off the mold.

We created the pattern for plank three, faired it, cut the blanks, measured, and then cut the planks. For seem reason (the hour? Too much coffee?) I cut a less than smooth curve that obliterated the line at several points. Geoff to the rescue. After much eyeballing and measuring, he began correcting the edge with a bench plane (#4?) and at the very end, a block plane. We lost only a 16^th of an inch from the design width...within tolerance. The gains were then cut as were the rolling bevels on the two #2 planks. The planks were offered up and some corrections made.

The bevel was wetted out (un-thickened epoxy) to saturate the end grain. This was quickly followed by thickened epoxy. The plank was held in place with clamps and temporary screws. Screws had been placed through the plank on molds 3,4, and 5 in the last fitting and then removed. The holes in the planks and molds could then be used to correctly register the planks. The whole process was repeated for the plank on the other side. In each case, squeeze out epoxy, inside and outside, was cleaned up.

Hahn was sent under the boat to do something besides clean squeeze out. He was given a drill with a ½ inch bit and asked to drill a holes near the ends of the centerboard slot. It was a tough job because the bit was last sharpened by Noah. Still, he succeeded admirably. Geoff then cut the whole slot using a straight router bit with a guide on it that rode on the keelson and cut the plywood to conform.

Next we began the last plank – the sheer plank – which is the one that catches the eye and can make or break the looks of a boat. In order to place the luan on the boat to create a pattern, notches had to be placed on both sides of the stems (saw and chisel) on the 2x4's to allow the pattern to reach down to the shear strake marks on the stems. 

The planking process was the same. I was reminded that after the plank is marked and cut in three pieces, and scarfed, it is aligned with the pattern placed over it. The second plank is placed on top of the glued and scarfed first plank, which serves as its pattern.  When we cut the scarfs this time, several of us used hand planes (I used my jack plane and block plane) and we all felt more comfortable than with the power plane. We had much better control.  The scarfed planks were held in place with strongbacks rather than screws this time. 

Geoff then had us return to working on the parts previously started. One operation involved rounding off the rudder head using a router with a pattern bit: 3/8” radius on the solid part and 1/4” on the sections where there was no middle section. 

Next we (read Geoff) studied the plans and planned how to cut the timbers for the aft end (skeg, etc). He then made up a cut list of oversized lumber for the forward keel, aft keel, etc. We then milled these parts to their rough dimensions. Brian planed the bottom of the boat so planks were no longer protruding and thus created a flat spot for all of the parts were were in the process of making. 

Some rudder theory. The railing edge should have a small flat area and then gently sweep down for about four inches. We placed the rudder in the rudder head and marked how far up this feathering would extend. The feathering was accomplished with the big grinder/sander initially (36 grit) – about half way up to the 4” mark. Then the standard 4” grinder was used with 24 grit on rubber sanding disk (this tool is used often by welders) to sculpt the edge of the rudder.  

End of the Day Progress

All photos of the Ness Yawl 2011 class may be viewed at: http://www.flickr.com/photos/21597525@N00/collections/72157627358772597/ 

Friday, August 12

Back to the garboards which require  a rebate to be cut at each end (upper outside edges). This rebate reduces the plank to ½ thickness at the bow and stern; a corresponding rebate is cut on underside of the upper edge of the next plank, so at the stems, there is only one plank thickness, half being contributed by each plank. The rebate width is the same as the plank overlap, that is, 3/4”; it goes 15” back from the stems. The thickness tapers from full dimension at 15” to half thickness at the stem. The work is done with a rabbet plane of sufficient width to cover the 3/4” wide rebate. This is done so only a single plank thickness intersects with the stems and can be faired into them.  Photos of cutting the rebates begin here.

Once the garboard was prepared, we created a pattern for the next plank. Three 8' sections of luan plywood are presented to the hull. The width has to be sufficient to cover the overlap and the mark on the molds indicating the bottom of the next plank. The three sections are maneuvered around to accomplish this on the full length of the boat. The sections were then hot glued, forming a single long pattern with an odd looking shape. The clamped panel was then marked. The garboard line was traced, the station marks for the plank bottom transferred, as was the plank bottom from the stems. The stems were also traced (outside). The #4 face was also indicated. The pattern was removed. The top edge was extended 3/4” to account for the overlap on the garboard plank (this is necessary since we traced the edge of the garboard, and the next plank must overlap by 3/4”. A spiling batten (about 3/4” square and longer than the pattern) is fitted. Nails were placed at the various marks, working from station 4 outward. We then stepped back to see if the curve was “fair”, that is, a graceful curve with no unsightly bulges. Small adjustments were made to the batten placement until the fit was good. It was then traced and the batten removed. Second plank photos can be seen here.

The pattern was then placed on top of a piece of a doubled up 4x8 x3/8” mercanti plywood; we cut both port and starboard planks together, insuring symmetry. . The pattern had to be transferred in three sections to this double piece of plywood. Thought had to be given to most efficiently fit the three sections of the pattern to the single piece of plywood.

One section was traced and a scarfing batten (3” wide strip of luan) was placed perpendicular to the section; this was marked “Under” or “Cut”. As you move from bow to stern, the forward part of the scarf is on top and the aft section underneath. The forward section is marked “Under”, meaning it has to be planed on the bottom, and the corresponding scarf on the next section is marked “Cut” since it will have wood removed to create the 8:1 sloping scarf. The marking of the scarfs was done on each of the three pieces. Each was marked as to which side of the boat it would be placed and an arrow pointing towards the bow was also drawn. Next, a 3/4” line was drawn around each of the sections to allow for some leeway in the final fitting of the plank to the mold. The three sections were then cut using the 6” circular saw. The two layers were separated and layed out. Care has to be taken to mark the parts cut from the bottom layer of plywood, and indicating their proper orientation. The scarf areas are drawn in and Under and Over noted on each scarf. This is a step that an error can easily be made and a scarf cut incorrectly.

Next we took the three pieces representing the plank on one side of the boat. Each piece was place on the workbench with the edge to be scarf aligned with the bench. A combination of power planers and hand planes were used used to cut the scarfs. Brian cut a very nice scarf using only his hand plane. The plank is then offered up to the boat. The spiling process was then repeated, again transferring marks from the stems, including their outline (lower edge), plank marks on the molds, station #4 and the edge of the garboard.

We then removed the plank a faired it using the batten. Again, the 3/4” overlap on the upper edge of the plank (note: upper refers to the orientation as we're looking at the boat, which is upside down, so the “upper” edge eventually becomes the bottom edge when the boat is righted). The rebate is created on the inner, upper edge of the plank ends so it will fit into the rebate cut earlier on the garboard plank.

The bevelled edge of the garboard is wetted with un-thickened epoxy. Then thickened epoxy is applied along the edges. The plank is then positioned (from #4 outward), and clamped and screwed where necessary (temporary screws).  The process is then repeated with the blanks for the other side of the boat. The rebates on the lower outside edge of the planks are cut after it is on the boat.

Using the same process, we created blanks for the third planks. The only difference was that when we scarfed them, instead of screwing them to the bench (with plastic protective sheets), we used a 2x3 piece of stock across the joint and clamped to both sides of the work bench.

We finished the first week by assembling starting assembly of the rudder, centerboard, centerboard box etc. as shown here.

End of Day, and Week Progress!

Week one was informative and fun. We have a great instructor and a diverse team with good chemistry.

All photos of the Ness Yawl 2011 class may be viewed at: http://www.flickr.com/photos/21597525@N00/collections/72157627358772597/ 

Thursday, August 11

We began by fitting the garboards, one at a time, to the molds. The plank is clamped  to the center station (mold #4) at one point and adjusted for the best fit, moving the it fore and aft, tilting it, or moving the entire board up and down. Once the fit is satisfactory, the garboard is clamped, moving outward from #4. We made sure there was sufficient overhang on each end.

The plank is then re-spiled.  Lines are traced from the stems to the garboard. Pencil marks are made at each station indicating the correct plank edge from the marks on the molds.

The centerboard slot was also drawn in. The garboard was removed to the bench and re-faired using battens. The process was repeated with the other garboard. At this time, the squeeze-out epoxy from the scarf joints on the garboards was also largely removed using a heat gun and scraper.

Thickened epoxy was then made and applied to the keelson, floor timbers, and stems wherever the garboard would land. The garboard was again fitted in place from the center out. Using #10 bronze wood screws, the plank was fastened to the floor timbers, keelson, and stems. 1” screws were appropriate for the keelson; 1 ¼” for the timbers. Temporary screws were used at the ends of the garboard to fasten them to the stems. The permanent screws were all pre-drilled and countersunk. The keelson screws have to be placed closer to the outer edges since the center area will be planed.  The photographs of this process can be found here.  The process was repeated for the second garboard. It overlapped the centerline too much, that is, interfered with the other garboard. Geoff made adjustments in situ with a hand plane.

Next we began fabricating components such as the centerboard, the centerboard box, and the rudder. These parts are clearly marked on Oughtred's plans. Brian Miller and I worked on the centerboard box. We cut the sides from plywood and then milled douglas fir to the specified dimensions for the rails (the fore and aft support at the top) and the logs (fore and aft support at the bottom of the box. They were left overly long and will be fitted later.

The rudder was built up to specified thickness by gluing 3/8” and 1/2” plywood together. Many glued-up components were gravity clamped, that is, heavy objects such as batteries, were placed on them.  See two photo sequence here.

From here on, any planks glued in place had to have excess epoxy scraped from the underside of the hull. This task fell to our youngest (12, soon to be 13), and smallest classmate, Han-Ray Jahn. He does an excellent job.

Then it was back to planking. We bevelled the garboard (see photo). This is a rolling bevel. To guide the planing, saw kerfs (photo here) were made at each station by holding the saw parallel to the mold section corresponding to the next plank and then sawn until it touched a 3/4” line scribed earlier (this is where the next plank will overlap the garboard.

End of Day Progress

All photos of the Ness Yawl 2011 class may be viewed at: http://www.flickr.com/photos/21597525@N00/collections/72157627358772597/ 

Wednesday, August 10

This was a challenging day.   The keelson was beveled, the floor boards were mounted, a pattern  was made for the garboards (the first strake or fore and aft board next to the keel), transferred to 3/8” plywood the the strakes shaped.

A bit more detail. At the point the keelson crosses each mold, a saw kerf was cut running from the centerline parallel to the adjoining part of each mold. This provided a guide for the subsequent planing; the angle changes as you move along the keelson. The rolling bevel is a common structural challenge in boat building. The bevel was cut initially using a hand power plane followed by hand plans. Frequent inspections were needed to insure that the bevel angles were correct along the keelson, and that, as always, the lines remained fair. The centerline on the keelson is sacrosanct; the bevel cannot erase it.  For photos of this, click here.

The floor timbers were fastened to the molds on the “downhill” side of each mold, i. e., on the bow side toward the bow and on the aft side toward the stern. The molds were appropriately marked, moved things along. The floor timbers were examined for fit. They were removed and some work was done with a Nicholson #50 rasp. Filing or rasping, one of our philosophical conundrums for today.

Once the fit as acceptable, they were screwed back to the molds, countersunk holes drilled through the keelson into the timbers and screws partially driven in. The keelson was then pulled away, thickened epoxy smeared between the floor timbers and the keelson, and the (1 1/2” #10 bronze)) screws driven the rest of the way.  This sequence can be seen by clicking on floor timbers.

Geoff then gave a talk about screws, pilot holes, and countersinks and introduced us to the Jamestown Distributors catalog.  Go to Jamestown Link

Next we needed to fabricate the garboard planks. To do this we constructed a pattern from ¼ “ luan (cheap) plywood. Distances were marked from the keelson centerline and the first inflection on the mold using a compass. The pattern was then placed on more ¼ inch luan which was hot gued together to provide sufficient length. The garboard was then transferred to the long luan blank and the blank cut out.   It was then fitted to the molds and corrections noted (e.g., +1/4 inch or -1/8 inch) at specific points. Once a satisfactory fit was achieved, the blank was placed on top of a  $75 4x8 piece of 3/8” meranti plywood. The long blank had to be traced in separate sections onto the plywood in such a way to make efficient use of the plywood.   A 3” scarfing pattern was made (just a 3” wide piece of luan). The parts 3 parts of the blank will have to be joined using a wedge shaped (side view) cut on adjoining pieces. The slope of this cut is 8:1, so for 3/8 inch plywood, the angled cut starts 3 inches from the edge.  The spiling and plank forming photos begin here.

End of the Day Progress Photo

All photos of the Ness Yawl 2011 class may be viewed at: http://www.flickr.com/photos/21597525@N00/collections/72157627358772597/ 

Tuesday, August 9

The class accomplished a lot today. This (and most boats) are constructed on a building frame, which in simplest terms, looks like a wide ladder, turned on its side, with short legs added. So this morning, using construction lumber, we started this phase.

Geoff quickly put together a cut list and various groups, using the chop saw, cut 2x4's, 2x6's, and lighter stock to the correct lengths. Since the 2x6's weren't long enough, two shorter pieces had to be joined using a short overlaying length of 2x6 (butt block). The two long (18+ feet) boards were placed on the floor standing on edge. Shorter 2x6's (think of them as the rungs of a ladder) were then screwed between them. A few 2x4's were then added to the ends to eventually receive the stems. Short legs were added (initially clamped). The whole structure was checked to make sure it was rectangular (instead of rhomboidal) and bracing was added. Careful attention was then paid to leveling the frame and permanently fastening the legs with deck screws. The whole thing was then screwed to the floor.

Next, the flatness of the tops of the long 2x6's was checked and adjusted. Geoff agreed it wouldn't have been a bad idea to run these through the jointer; it would have made life a little easier. We also ran a centerline string from one end of the frame to the other.  To see the sequence of photos showing the construction of the building frame click here

Next we discussed how molds patterns are represented on the plans and various ways of building them.  Photos are here. To make this project feasible in our two week period, Geoff let us use his molds. These are attached at specified “stations” along the two side rails. The plywood molds obviously have two faces; only one, however, is the station face and needs to sit precisely at the station marks. These are screwed to the frame (the have a 2x2 on the bottom edge to allow this), making sure that the centerline string crosses at the vertical centerline of the mold. Next the molds have to be made perfectly vertical using a level and light bracing.

At this point, two of the students took a piece of douglas fir and milled it to the correct specifications for the keelson. The rest of us released the inner and outer fore and aft stems from the jig on which we bent and epoxied them yesterday. Voila! The stems came free, even the double one, on which the outer and inner inner stems were fabricated together, separated by a strip of polyethylene. Next we cleaned them up by running a power planer over the sides and sanded with 36 grit sandpaper glued to a piece of formica (which is a neat sanding block that has the flexibility to conform to the curves). Finally, they were run through the thickness planer to achieve the correct width. Some of us thought that if we did this on our own we would laminate somewhat wider strips to give us a little more leeway in this final shaping. A total of three stems were made: bow (inner and outer), and stern (inner). The stern outer stem will be fabricated from lumber later.   It should be noted that all of the appropriate markings, which are indicated on the jigs, should be carefully transferred to all of the stems.  We had to go back and do this later.

The next step involved beveling the inner edge to the angle specified in the plans. This angle varies along the length, but Geoff gave us a compromise angle for the entire length to make life easier. The bevel was cut with a hand power plane, but some dressing up was done with block planes and spokeshaves.  The inner stems were then dry fitted on the molds along with the newly dimensioned keelson. A line was drawn on each stem where it met the keelson to insure an appropriate landing. This took a lot of adjusting, using the bandsaw, and power and hand planes. When Geoff was satisfied, the stems were screwed to the frame at their tip, and they were adjusted to make sure they landed on the molds at the right point.  As stated earlier the stems had been marked from reference lines while they were still in the jig to give as these calibration points. A few countersunk screws were placed on the stem where it meets the keelson, but only driven in to just touch the keelson. Finally, epoxy was mixed (peanut butter thickness), and was slathered into the space between the stems and keelson. They were  clamped, and the screws driven home.  Click on stem photo sequence and go through it be clicking on "next" from the first photo.

A few other students, working from Geoff's patterns, cut out the floor timbers. These are the structures that run from side to side, stiffen the garboard, and provide a surface for the boards that you actually stand on. These were temporarily fastened to the molds and checked for fit. Once the fit was satisfactory, usually involving a bit of filing (or is it rasping?) with a Nichols #50 rasp.  Click here for photos of this.

Wow! It looks like we're building a boat.

End of the Day Progress

All photos of the Ness Yawl 2011 class may be viewed at: http://www.flickr.com/photos/21597525@N00/collections/72157627358772597/ 

Monday, August 8

The day began with the large-machine orientation, including a very large bandsaw, a Sawstop table saw, a jointer and large planer. Plenty of opportunity to do major damage.

Geoff, our instructor, then took us out to the student parking lot and gave a detailed talk on his Caledonia yawl, which he built 15 years ago. This Oughtred design is very similar to the Ness Yawl that we'll be building; it's just has a larger beam and volume. For a photos of the boat,  go to Ned Ludd.
Click on "newer" to go through sequence.

Geoff set up both masts and all of the rigging while the boat was on the trailer. One person can lift all of the spars, and they store inside of the boat. The simplicity and functionality of the rig is amazing. To heave-to you simply release the main sheet and sheet in the mizzen; the rudder takes care of itself.

We then returned to the shop and Geoff went over the plans for the Ness Yawl. An amazing amount of information is contained in them, including full-sized patterns for critical parts such as the inner and outer stems (bow and stern) as well as the molds we'll be setting up tomorrow on which the boat is actually built.

We then had a waterfront orientation, which allows us to sail or row any of the amazing collection of classic boats.

In the afternoon we were introduced to the epoxy (MAS) we'll be using. We then did our first actually building, laminating the inner and outer stems (bow) and inner stern stem. We epoxied the thin pieces of douglas fir together and then clamped them into the two jigs.  The inner and outer bow stems were constructed on the same mold; they were separated by a sheet of 4 mil poly.  Anything you don't want epoxied needs to be covered with plastic sheeting.  Photos of this process can be found at Laminating the Stems   Once on first photo, click "older" to go through sequence.  

Much of the afternoon covered mold making and setting up the building frame.  Making sure it is level and square is critical.  Legs are initially clamped until the frame is level, then screwed in place with drywall screws.  A center line is attached.  Photos of the frame building process can be found at   Building the Frame.  Once on first photo, click on "older" to go through sequence.

Tomorrow we will set up the molds and attach the stems, keel, etc.

By the way, no one is starving. The food is good and plentiful.

End of the day progress photo

All photos of the Ness Yawl 2011 class may be viewed at: http://www.flickr.com/photos/21597525@N00/collections/72157627358772597/

Sunday, August 7 - Arrival

Off to a good start. After an 8 hour drive from Queensbury (much of it in the rain) I arrived at the Mountain Ash Student House, which is about a mile from campus, to get my room assignment. Then moved my stuff to the second floor garret (I'll never again tell Jane she packs too much stuff). Checked the list a second time an realized my finger had slipped to the next line. Re-packed, schlepped the stuff to the car, and went to my real room in the Farmhouse on campus.

My roommate is a nice guy, Yenching We, a retired cardiac surgeon from Clovis (near Fresno, CA). We went to dinner back at the Mountain Ash House which was crowded since everyone – resident and non-resident students and assorted guests – get to eat on the opening night.

We then went back to the workshop for a general orientation and  received more specific information from our instructor, Geoff Kerr. Seems like a good guy and certainly has more experience than anyone building Oughtred designs, specifically the Ness Yawl and the Caledonia Yawl. Got to briefly meet the rest of the class. There are eight students plus Geoff.

The real work starts tomorrow at 8 am. Besides starting the actual building process, we will also get a waterfront orientation at lunch (weather permitting). They actually let you sail or row their fleet of beautiful wooden boats.

The days will be very full and I still need to get a run in once in a while, and also a little guitar practice (need to find a secret place to do that). Hope I can keep posting text and some photos as we progress. We don't build on the weekend, so I can do some catching up then...unless we go sailing.

All photos of the Ness Yawl 2011 class may be viewed at: http://www.flickr.com/photos/21597525@N00/collections/72157627358772597/