Thursday, October 31, 2013

Happy Halloween!

So, what kind of candy did you get?




Thursday, October 24, 2013

Thought for the Day

The only place where "success" comes before "work" is in the dictionary.

                                                                                               - Vince Lombardi

Tuesday, October 22, 2013

Tech Tip Tuesday

Non-Traditional Skin-on-Frame design may be converted from other more traditional designs relatively easily.  The easiest designs to convert are those that have faceted cross-sections.  For someone looking for faceted designs, existing lapstrake and stitch-and-glue designs would be good candidates.   Round-bottomed designs - like traditional canoes tend to be -  can be converted as well, but there is a little bit more trial and error in creating the "flats" along the curve, because you want the stringers to be "fair" curves along the length of the boat.


 Lapstrake Boat


 Stitch-and-Glue Eastport Pram

There are some caveats, however. 

You need to plan for a design where the facets are not very wide - if they are, you may need to break up the "panel" into a smaller width.  By "wide" I mean panels more than 10" or a foot wide.   If the fabric panels are wide and the fabric isn't tight enough, it can sag under water pressure - perhaps hitting a frame - which will slow the boat in the water. 

The other main caveat is that the stringers don't want to have lots of force applied to the hull in the "up" and "down" direction.  This is particularly true of the gunwales or the sheer clamps on the boat.  Excessive forces can cause the hull to bend with more rocker - the fore-and-aft curvature of the hull that is reminiscent of the shape a rocker on a rocking chair - or hogging - a reverse bend where the middle of the keel is higher than the ends.   The other issue is that the hull can distort from the forces.   These forces applied to the hull can be minimized by pre-bending, laminating stringers to the curve, steaming the stringers to shape.

There are some other minor concerns.  One is fabric width.  You may want to be able to build the boat with one single piece of fabric so you don't have a seam at the bottom.  This may not be possible and you may have to stitch multiple pieces of fabric together, but this isn't a disaster or an impossibility. 

One item that should not be ignored - for any boat building -  is that you need to have the correct scantlings for the boat.  Scantlings are the appropriate dimensional timbers for a given size of boat.  This would include the right thickness of plywood - typically 1/2" for small boats - and the correct stringer cross-section.  The boats that we're building have stringers that range from 5/8" square to as big as 1-1/2"x 3/4".   Boats that are designed for paddling - such as a canoe, pirogue or kayak - will have structural elements such as decks or breasthooks, thwarts, floors, coamings and the like to help keep the shape of the boat.  Boats designed for rowing or sailing have other concerns.  For sailing boats, they need to hold their shape when the forces of wind and water are applied to the centerboard/daggerboard and trunk, rudder, mast partners, and mast step.  Rowing craft need to have a strong enough seat and gunwales/oarlocks to resist to forces applied by the rower to the hull.

Wednesday, October 16, 2013

Tuesday, October 15, 2013

This One is for Tom Jackson

So, this past weekend, my DW flew to the UK for a milestone birthday for her Mum.  (One doesn't disclose the age of a lady, of course.)  It was an excellent opportunity for the family to be together and while it would have been nice to have been able for the whole family to go, it's just a bit prohibitive to fly a family of 4 to the UK for the weekend...

At any rate, DW was planning on flying Icelandair to the UK as the price was very good.  The other concern was that she was able to obtain a re-bookable business class ticket for a good price in case she needed to re-schedule for whatever reason.  There were a few nice perks to this, including use of the airport lounges and a bit better seating, but I keep reminding her that she shouldn't get used to it...

The one thing about flying on Icelandair is that the flight hub is Reykjavik's Keflavik International Airport - actually located down the coast in Keflavik, so the flight that she took to Manchester airport in the UK had stop-overs in Iceland.  On the return leg, she had some time to kill and wanted to pick up some things for DD, DS and myself.  She chose some t-shirts.

This is where Tom Jackson fits in.

The man both edits and writes for WoodenBoat Magazine and really looks the part of a Viking.  Ironically, he wrote an article in issue 206 about a trip he took from Dublin to Denmark on a reproduction Viking longship.  He's a powerfully built man with a salt-and-pepper beard and a quiet thoughtful demeanor and good sense of humor, actually.

One of the last times I saw Tom, he was wearing a WoodenBoat T-shirt with a Viking proverb on the back : "Bundin er båtlaus mardur." - literally - "Bound is boatless man."  Being that the front of the shirt is the WoodenBoat logo - a Viking longship viewed bow on, I figured he'd have loved to get his hands on both the shirt my DW brought me back and the bag it came home in:



Wednesday, October 9, 2013

Wednesday, October 2, 2013

Wordless Wednesday


Must be a member of Congress...

Tuesday, October 1, 2013

Tech Tip Tuesday

So, now that you've decided to build a skin-on-frame boat, you're looking for instructions and plans, aren't you?  Let's take a little look around at some of the plans that are available:

Traditional Build:

Most books for traditional skin-on-frame boat building generally target kayaks or canoes.  If you look around the internet, you'll find instructions and classes for building things like coracles, umiaks, basket boats, kayaks and canoes.  Not really all that difficult if you're looking.

If you're going really "Old School", David W. Zimmerly's Qayaq: Kayaks of Alaska and Siberia has some neat drawings and images of traditional kayaks.  It would be for an advanced builder to interpret things from the sketches in a way that fits the individual paddler.  You have to keep in mind that the Innuit used body measurements - hand spans, cubits, and the like to make their boats - they were tailored to the builder.

Some more up-to-date books to build versions of the Greenland kayaks are written by Christopher Cunningham and Mark Starr.  Cunningham has written Building the Greenland Kayak: A Manual for It's Construction and Use while Starr has written Building a Greenland Kayak.  Both are excellent books and I recommend them highly if you intend to build a traditional kayak.

While Starr and Cunningham's books are both very good, I'd have to rate Robert Morris' book Building Skin-on-Frame Boats to be excellent - it delves deeply into the build of kayaks, but also talks about other type of boats including prams, canoes, and umiaks in the back of the book.  Morris owns Brewery Creek Small Boat Shop in Vancouver, Canada.  He appears to have been strongly influenced by Zimmerly's research and writing - which is a good thing.  The book is out of print, but if you can find it, borrow it or get it at your local library, I highly recommend it - whatever method of skin-on-frame you intend to try.

Qajac USA, the American Chapter of the Greenland Kayak Association also has an excellent listing on their website of resources information for builders including books, weblinks, and video - check it out here.

For canoes, Hilary Russell of the Berkshire Boatbuilding School has done more than most to bring about the building of small skin-on-frame canoes in the tradition of Rushton's small double-paddle canoes.  Sometimes he works with sawn woods, sometimes with natural materials - typically willow.   He offers plans, kits, parts and a book - Building Skin-on-Frame Double Paddle Canoes as well as classes.  The boats are lashed frames with steam-bent ribs and Nylon or Polyester skins.  He also had two articles in WoodenBoat Magazine on the buildling of one of his boats - that includes plans - in WoodenBoat issues #205 and #206 - available from the WoodenBoat Store as PDF downloads.   I met a woman this summer while out paddling who had taken  his class and built the boat she was paddling - a beautiful specimen, to be sure.  I'm still tempted to build one.

Sorta Traditional Build...

No listing of kayak building resources for skin-on-frame boats would be complete without the seminal classic, Baidarka: The Kayak by George Dyson.  George and friends built a variety of baidarka - including some massive sailing versions in the '70's.  These boats are not wood framed, but are framed from lashed aluminum plate and tubing and skinned with nylon fabrics - basically a high-tech twist in terms of materials on classic designs.  George is still very influential in the skin boat world and owns Dyson, Baidarka & Company in Bellingham, Washington.  George supplies a significant portion of the Nylon and Polyester fabrics used to skin boats today.  My students and I purchase our fabrics from him.  A nice gentleman to deal with with broad interests and a depth of knowledge.

Bridging the gap again is Wood and Canvas Kayak Building by George Putz. It's a unique, slightly homespun book and could perhaps use some updating in terms of skin materials.  In particular, the use of a "truss" system along the sides of the boat along with "floors" very similar to the construction of larger sail boats is unique.  Well worth a read if you find it.

I'm torn about where to put this one.  Geodesic AiroLITE boats designed by the late Platt Monfort and still offered by his family in the form of both plan, kits and partial kits are really a bit more high-tech than most "traditional" methods.  He used steam-bent ribs in his designs and lashed stringers to them.   He then used Kevlar "diagonals" to ensure that the boat's frame stayed rigid.  The skins and skinning methods were really borrowed from the aircraft industry and are a bit unique to skin-on-frame boatbuiding.  There are a wide variety of plans offered including paddling, pulling and sailing craft.  The thing that's special about the Geodesic AiroLITE boats is their impressively light weight.  A gossamer 12 foot long canoe can weigh as little as 14 pounds.  Truly impressive.

Non-Traditional Builds:

I would do a disservice to the history of non-traditional skin-on-frame boats if I didn't include Percy Blandford.  (Some information on this website.)  Percy designed skin-on-frame kayaks that were very popular in the UK from the '30's to the '70's including the PBK10, PBK14, PBK 20 and PBK 27.  He also wrote a book called Canoes and Canoeing - now out of print.  They were very popular with Scouts in the UK.  Plans are available from Clarkcraft.com.   Most, if not all of the designers offering plans below, owe some credit to the efforts of Mr. Blandford.

Tom Yost has taken what Percy Blandford did and ran with it.  Tom offers a website of free designs and building instructions on his website, Yostwerks.   The offerings on the website include boats with plywood frames, wood stringers and PVC skins.  Other offerings include folding aluminum and plastic frames with PVC skin and inflatable PVC boats.  The designs have evolved over time and some of the older designs have faded away.  There is also a Yahoo! group dedicated to Tom's boats.  All of Tom's work is well worth looking at, but I'd recommend skipping the PVC skins to save weight and look at Nylon or Polyester.

Dave Gentry of Gentry's Custom Boats seems to have started on his path with Yost designs and evolved into his own with an impressive selection of kayaks, canoes, pulling and sailing boats.  Dave's offerings seem to be expanding on a regular basis.  He offers both plans and kits at his website and offers classes at the WoodenBoat School along with other locations.  This year, my students will be building three of Dave's designs including his Chuckanut 15 kayak, IGO canoe, and Annabelle sailing skiff.   His building tutorials that come with the plans are quite good and a nice addition.   I'm looking forward to the time when Dave writes a book on the subject.

S. Jeff Horton of Kudzu Craft offers skin-on-frame kayaks, canoes, pirogues and pulling boats.  He offers plans, kits, parts and two books - Building Fuselage Frame Boats and More Fuselage Frame Boats.  My students will be building three Stonefly canoes from the first book - we built a total of eight of them last year.  Overall, Jeff seems to specialize in the kayaks, but the other offerings are interesting.  The instructions tend to be somewhat simplistic in the book, but are still a very solid offering for someone who wants to build their own boat at home.

In next week's Tech Tip Tuesday, I hope to discuss the idea of converting existing designs to skin-on-frame designs.