Tips, Tricks, and Hints Requested: Tapering Wooden Masts

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I'm afraid that I agree with enemeink.  Although there are modeler's lathes available, they are quite expensive. Fitting a wooden mast or spar in a powerdrill, turning it on to low power, and sanding works as well as a lathe, in my opinion. It's cheaper, too.

Bill Morrison

Thanks Bill and enemeink! 

I've thought about this, but wasn't sure whether the drill should be held stationary in a vise or jig of some sort - your thoughts?  Also, do you think that the other end of the dowel needs to be somehow supported (e.g. fix in a chuck or some jig that rotates, but restricts lateral movement while it rotates)?

Maybe I'm making this too complicated... I look forward to your additional thoughts.

Cheers, Rick 

I wrap the end of the dowel to be secured in tissue or a light piece of cloth to protect the wood, then place that end in the drill chuck, tighten the chuck, then wrap the end to be tapered in approximately 1" heavy grit sand paper. I then turn the drill on, shaping as I go.  When I get roughly the right taper, I switch to finer grade sand paper and repeating the process, eventually working to an even finer grit.  Before you know it, I have a tapered spar or mast without investing a lot of time or money.

Bill Morrison

Rick:

I have used the method that Bill discusses and it works fairly well. I hold the cordless drill in one hand and wrap the piece with sandpaper with the other, working down from the end. There is liable to be some deflection as you go down towards the drill end of the piece, but unless the piece is really long, that should not be a problem. I have tapered spars that were as much as 18 inches long with a hand held drill. If possible, use a dowel that is longer than your finished piece. That way, you can chuck it up without worrying about what happens to that portion in the chuck.

Be advised that the store bought dowels used in kits may take more time to taper than when using a strip of hardwood. The main thing is to work steadily at it and do not get discouraged if it takes some time to get the piece down to size.

Russ

For this sort of thing an old-fashioned electric drill will work almost as well as a lathe.  In this context the lathe really has only one feature that the drill doesn't:  a tailstock, which holds the "free" end of the wood.  I've had a Unimat SL lathe for about 35 years; it's too small for the tailstock to be of any use on anything but small spars.  When I need to make a spar longer than about 4" I either remove the tailstock or use a drill; there's virtually no difference in the results.  If you've got an electric drill you can make nice spars.

I do recommend fastening the drill down in some way - either in a vise, or to a "Workmate" -type portable workbench, or with a clamp, or with some gadget that's designed for the purpose.  If you're right-handed, mount the drill on the right side of the workbench.  Fasten it down in such a way that you can get at the trigger and the button that locks it in the "on" position.  (That usually means upside-down.) 

The other two things you need are some sandpaper in various grits (from medium to the finest you can find) and a fairly heavy rag.  Fold the sandpaper over several times into a fairly thick pad.

You'll also need some sort of caliper or other measuring device.  Nowadays really nice calipers are available for surprisingly low prices.  (The cheapest I've seen are these, which probably would be perfectly adequate for most modeling purposes:  http://www.leevalley.com/wood/page.aspx?c=2&p=52906&cat=1,43513,43546&ap=1 .  Even the ritzy digital models don't cost much these days, though:  http://www.woodcraft.com/family.aspx?FamilyID=20126 .  A digital caliper that works in both inch and metric systems comes in handy for all sorts of modeling purposes.)

Your left hand (if you're right-handed) will be the tailstock.  (Something has to prevent the wood from whipping around.)  I'm assuming you've already got the spar reduced to the form of a dowel, and that it will fit in the chuck of the drill.  Leave the dowel long enough that you can saw off the part that gets squished by the chuck afterward.  Chuck the dowel firmly into the drill, get a good handfull of the rag in your left hand (to keep your fingers from getting burned), and grab the end of the dowel in your left hand.  Turn on the drill, set the speed where it seems about right (probably the fastest speed the drill will turn), and lock it.  Take the pad of sandpaper in your right hand and hold it up against the rotating dowel.  (I find it's comfortable to squeeze the dowel between two layers of sandpaper.  For smaller spars I sometimes use a narrow strip of sandpaper and wrap it around the dowel.)  Apply pressure gently at first, and keep the sandpaper moving along the length of the dowel.  Start out with medium-grit sandpaper, and work your way down to the finest.  If you stick with it you can produce spars with an almost polished-looking finish.

It sounds primitive, and it is, but it works.  The truth of the matter is that in terms of tools and mechanics, woodturning, even on a big, expensive lathe, isn't much more sophisticated than this.  (The pro holds his chisels, gouges, and scrapers in his hand, and when he gets close to the finished dimensions he switches to sandpaper held in his hand.) 

It does take some practice, and it's a good idea to buy plenty of dowels stock for practice.  But my guess is that by the end of the first evening you'll be turning out spars that are as good as anybody else's.

Hope that helps a little.  Good luck.

One other point.  Take care when shopping for dowels.

The dowels sold in most American hardware stores and home centers these days seem to be made of two species:  oak and birch.  (I get the impression that a place like Lowe's or Home Depot gets whichever the distributor happens to have in stock.)  I recommend avoiding oak; its grain is too coarse, and when turned down to small diameters it gets brittle.  Birch is a nice, workable wood and makes good spars; it is in fact what the American wood kit manufacturers normally supply for the purpose.  (I imagine the spars supplied in the Bluejacket kit are birch.)If you buy a birch dowel, though, take the time to sight down the length of it and make sure it's straight.  If it isn't, don't buy it.  And try to see that the grain is parallel to the length.  (That isn't always easy; the grain of unstained birch is hard to see.)  If it isn't, the dowel is likely to warp.

Some places sell maple dowels.  Maple is nice stuff, but a good bit less springy than birch.  Whether that's an advantage or a disadvantage depends, I guess, on what you're going to do with it.  If the only species you can find is maple, my suggestion is to try it.

Woodworking supply companies sell cherry dowels:    http://www.woodcraft.com/family.aspx?FamilyID=667 .  I used cherry for the spars of my last model, and really liked it.  It's a bit on the dark side (in the coloration sense - not the Darth Vader one), but turns nicely and takes a beautiful finish.  I don't recommend the walnut dowels that Woodcraft also sells.  Walnut is exquisite stuff for furniture making, but the grain of it is too coarse and brittle for this particular purpose.  (I'm talking here strictly about American walnut.  I have the impression that the European variants of the species work quite a bit differently.)

Hope that helps a little.  Good luck. 

John:

I know from experience that dowels are cut in such a way that the grain almost never runs entirely in one direction. There are bound to be cross grained sections in any dowel, regardless of species that could lead to warpage. That does not mean that every dowel will warp, but it is a possibility with any dowel, no matter how straight it looks in the store. That is why I avoid using them at all. Its much better to get a straight sawn stick of hardwood and make a spar out of that. With a stick of hardwood ripped to rough dimensions, you will always know how the grain runs. With a dowel, you almost never know for sure.

Russ

 The masts and booms on Sihaya,

were tapered, and rounded from square stock, using an old XActo spoke shave, and sand paper.  The topmast is orange wood. As Jtilley mentioned, Cherry is also a good wood. I've used it, and enjoyed working with it. Sihaya, is planked with Mahogany strips.....I liked the finish color, but would not recommend this material for hull planking, it was very difficult to work with.

Yes, Russ, it's always preferable to start off by ripping (or, even better, splitting) the stock from a board - though that's no absolute guarantee of getting grain that runs perfectly parallel to the spar.  And it's true that the grain of a three-foot dowel, almost by definition, will not be parallel to the length for the whole three feet.  But not everybody has the means of turning rectangular stock into round - and that's a job I wouldn't want to attempt with a hand drill.  And the grain in a birch dowel is highly unlikely to give trouble, especially if you're careful.  Take a good close look at the grain, and saw the piece you're going to use out of a section where the grain is straight.

In fifty-two years of model building I've used dozens - probably hundreds - of birch dowels, and I have yet to see one warp after I've shaped it.  (I've also thrown out a few that warped in my shop after I bought them, but before I used them.)  I've also cut plenty of spars from boards, for that matter, and I've never had any significant warpage problem with them either.  Just be careful, and watch how the grain runs.

I agree with Professor Tilley. I have used birch for years and have never had a problem.

Bill Morrison

Many years ago Harold Underhill wrote a much respected and beloved pair of books called Plank-on-Frame Modeling and Scale Masting and Rigging.  Those two volumes probably are basic to thousands of ship modelers' libraries, certainly including mine.  I think it was in Vol. II that he made the famous observation about commercially-supplied dowels warping into "the shape of a dog's hind leg."  That's the sort of verbiage that rings down the decades, and I think it's had quite an influence in scaring modelers away from commercial dowels.

I'm one of Underhill's biggest fans; if he said he saw a dowel do that, I'm sure he did.  I suspect, though, that methods of growing, selecting, and seasoning birch (and maple and cherry) have improved since then.  Every once in a while I see a dowel in a hardware store or hobby shop that's warped into a gentle arc; that one I don't buy.  But I've got dozens of them in my workshop, some of which have been sitting there for - well, I have no idea how long.  None of them shows any sign of warping.

I'm not suggesting that dowels don't warp; they do.  I do think, however, that the problem has been greatly exaggerated over the years.

I have a box of old spare scrap wood and a multitude of dowels that have been sitting unused for years. Upon inspection since this thread began, none of the dowels have warped, curved, or become distorted in any way. I therefore agree; it is an overstated problem.

Bill Morrison