Some comments on boat building, designers and, how it was done.

On laying out for fasteners in the backbone:
In times past some designers would include a "proposed" fastening layout for the backbone of a vessel. This was a guideline for prospective professional builders but, it was not meant to be a hard and fast rule. Descretion on the part of the builder was taken for granted. In the shop, experience counted just as much if not more than a proposed fastening layout. The builder( professional) would in the loft, layout the fastening schedule on the backbone lines and see just where they fell. If it looked doable he went ahead with the designers plan. If not he would change it to fit the way he viewed the structural members.

Part of the above by the designer was based on his choice of wood/s for the backbone. Usually White Oak or Douglas Fir or Longleaf Yellow Pine, depending on where he was or where the vessel was to be built. Not going to specify a 14 inch x 14 inch x40 foot, White Oak keel out on the west coast are you? Douglas Fir or perhaps a wood from the Pacific Rim or Australia like Red Gum would be easier to come bye than White Oak from the east coast and the expense of cutting, milling and shipping of that piece. In that case the scantlings aka dimensions of the timber/s would sometimes be altered bye the designer in correspondence with the builder.

These accomodations for geography, economics were to be expected and not unusual. Another example, eastern north american White Pine was often called for as stopwaters. Now, if you are in say, San Francisco, California or Seattle, Washington State, are you going to have your lumber supplier special order White Pine from the east when perfectly good Alaskan Yellow Cedar or Port Orford Cedar is on the shelf? No, you are going to go with the Cedar. The same holds true for decking. White Pine was often called for for decking but on the west coast of north america, Douglas Fir was the usual replacement.

On this business of how to treat decks with an oiled finish:
Yes, it was not uncommon to use 'boiled' Linseed Oil, real distilled Turpentine, Pine Tar and perhaps some other personal yard favourites. BUT...the mix was ***not*** used cold, it was warmed up to almost hot. As in, you could poke your finger in it just, without getting burned. It was brushed on with those big old whitewash brushes when the deck had warmed up in the sun. It was warm decks and warm oil mixture. I cannot recall it being sticky, though any excess was not left standing on the deck but, brushed off, let dry for a day or so and if necessary any bare or dry spots would be then given another coat. I seem to recall that if any of the mix was left over it was let cool and some turps was poured on the top before the lid was attached to the pail.

On the use of drifts:
Nothing wrong with drifts. Just have to know how to make and apply them, is all. Snug fit but not too tight, barb or nick the shanks. Peen the head over before inserting, don't expect the driving to make a nice head if you are putting in a 12 or 16 inch long drift! Use a nice over size as in outsize diameter washer under the head and don't use something like a 'fender washer' either. Make or have made decent thickness and diameter washers. If you are going to counterbore the drift heads then make up a suitable counterbore. Two ways come to mind in making or fabricating such. WL Fuller sells a Multi-Spur cutter. No, not the Multi-Spur Bit but a cutter made to be attached to a shaft.

Mine are like this: a length of 4140 alloy steel ( my favourite alloy for such things) is milled and turned bye my 'friendly neighborhood machine shop'. Size is approx. 6 or 8 inches overall bye 1.50 inch diameter, 3 milled flats are made on one end to fit the jaws of a 1/2 inch Jacobs Drill Chuck, the shank is turned down to .50 inches in diameter for most of its length. The cutter head is slipped down the shank as it has a .50 inch bore through it till it is stopped bye the thicker end. The cutter head has an Allen screw in its base so a milled flat is made on the shaft to accept it. The thicker end is now turned to the bore size/s needed. My suit of such counterbores goes from 3/8ths inch to 1.50 inch in diameter. They are a snug fit in the already bored hole and if too tight in a drift boring, then a proper size bit Jobbers style is run down the hole just far enough to allow the counterbore to do its cutting and no farther. The counterbore is highly polished,I buffed them on a big 'polishing lathe' with jewelers rouge and the end is chamfered too.

The alternative for home builders is to get an Irwin Speedbore aka Spade bit of the outside diameter needed and have a length of round stock of the needed diameter cut to about 3 or 4 inches in length and a slit cut on one end and that Irwin bit with the point ground off inserted in the slit and then a hole bored through the whole assembly and a rivet inserted and peened over to hold the rod on the bit and that works for a number of holes but is not anywhere near as elegant nor as efficient as the Multi-Spur/turned and milled device.

Don't forget to clear the chips from the hole during boring and afterwards too. Air or a narrow pipe nozzle for your shop vac works fine. It is not too difficult to see that the bit needs to be withdrawn often to clear those chips or you are going to wind up with an expensive auger bit as a drift. Not too good, or so says I.

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