Thursday, May 8, 2008

Keepin' it Together...

New Poll asks readers which fasteners they use most...

After receiving our best feedback to date with the last Poll, I've added a new one today for all of the Working Wood readers out there. 'The Poll', for those who don't actually realise you can scroll down the page via that little arrow over there at the lower right hand side of the screen, is a weekly updated section of the site where devoted readers will answer questions directly related to their wood working preferences. Go ahead now, scroll down and look for it there on the bottom right side. Make your voice heard! Vote...Besides, it's a great way to see if you're working on 'The Road Less Travelled' or simply following the norm. (And no, not the New-Yankee type of Norm )
Today's topic deals with your most used method of attaching or fastening wood together. Do you use Hand cut joinery or store bought dowels, cut nails or cast Bronze screws? Time tested methods are all over the place for you to refer to, all you have to do is take look around.

A Fastener for Every Application

It seems no matter what it is you're building there's a special way of 'keepin' things together'. Maybe you're building a small side table and all of the components are held tightly together by accurately cut hand joinery. Bridle joints and dovetails, aprons cleanly mortised into the legs. A little glue perhaps? Ahh now, which kind will you use my boy? Fish glues or Hide, Polyvinyl Acetate Glue (PVA) or Fast curing Epoxy? Let's leave the glue types for another day and actually look at the different mechanical fasteners used. So, the small side table, with it's apron mortised into the legs. Did you draw bore the tenons, pulling them together for a tight fitting joint that will probably be around for someone else to dissect in 100 years? If you did you use a dowel, where did you get it? A scrap piece or off-cut, left over form the same project? Driven like a pile driver, down through a dowel plate, shearing off the edges making a rounded wooden cone to draw things together. Maybe a store bought dowel of a different species to accentuate the contrasting wood types being used. No dowel? No problem; a cut nail is not only historically accurate to alot of period style pieces, it's a great way to use a mechanical fastener without having to spend the time to cut fancy joinery. A gimlet in hand and twist in a pilot hole, you're done. Simple butt-joints, grooves or dadoes as well can safely be fused together with nails; driven in at opposing angles they can be as strong as any other fastener I can think of.
Maybe you subscribe to the cordless drill and screw methods of work. A 22 Volt, super-charged, impact driving wrist-breaker that can sink 4" screws into hard Maple all afternoon! Perfect! If that's what works for you then all the power to ya! Besides, you'll need the power to keep that thing running. I actually use screws in a lot of my work depending on the project. Take the Cherry Kitchen cabinets I recently finished; pocket holes and yellow carpenters glue all over the place. Did I use them in the small five-drawer table I recently made from Birds Eye Maple and Black Cherry? Of course not, it would have taken away from the piece and stood out like a sore thumb. Nails could have been used for sure, but I chose to join everything with beautifully cut joinery and glued things together. I could always go back and add some dowels later if need be. I don't think it will be necessary but it's nice to have the option.
A little trick I'll share with you here involves using screws during set up and finishing off with dowels. I'll explain further...

Borrowed from the Boat Shop

Having a background in wooden boat building, I've been aware of different techniques used to fasten wood together and expect it to withstand all sorts of harsh environments. Much more than any other piece of furniture I've designed; unless it's being installed on the deck of the Titantic, I don't think we have to worry about the same forces reacting to a dovetailed cabinet as say a traditional North Atlantic Dinghy. When manipulating wooden planks to conform into the tortured twisted form we see as a finished boat we sometimes will use screws like small clamps every few inches along a seam. After sufficient drying times on what-ever type of bonding agent was spread into the joint, once dry we remove the screws and fill the holes with wooden Bungs or an Epoxy mixture. This works well especially when working alone and can't seem to find a way to fit that third hand around a piece to hold it together while the glue dries. Clamps are great, don't get me wrong, but sometimes they simply won't do the job required. So a wood screw driven through like a spike down into a railway tie. Just long enough, until everything sets and then slowly back it out. Never drive them deep enough to damage the surface fibers of the wood grain when removing them. Another thing to consider is where to place them; keep things symmetrical and pleasing to the eye. And now what to do with all of the screw holes? I use the Miller Dowel System to fill them in. The smallest size dowel they have is a great size to fill a #8 screw hole. Carefully pre-drill the already existing screw hole left behind with the appropriate drill bit supplied by the Miller Dowel System. They offer a few different wood species and three different size dowels. When you're done, all you see is a smartly placed dowel along a seam or joint. No one will ever know you were filling a screw hole made during the 'clamping-up' stages of building. A great way to hold difficult glu-ups or anywhere you may want to use a dowel instead of a nail or screw. Let me know how it goes.



The Miller Dowel System is available through mail order from Lee Valley Tools.

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