Wednesday, June 8, 2011

Using a template to cut shapes with a router

This is just a quick how-to on a technique I use to quickly cut shapes in wood.  I've used it for decorative shapes on outdoor projects and curved legs on furniture, among other things.  It's really a time saver when you need to make several of the same shape, and you can keep the templates and use the curves on other projects down the road.  I just re-used a template I made several years ago (for a garden arbor) to cut decorative ends on the cedar beam across the top of a trellis structure.

1.  Make the shape.  I usually draw the shape at full scale on a piece of graph paper, or sometimes with software, and print it out.  Sketchup (free and excellent) or Adobe Illustrator (expensive but powerful) can both be used to make all sorts of curves.  Pencils work pretty well, too.
A template design I made in Illustrator
2.  Cut the template.  Plywood or hardboard is best for this, and 1/4" to 1/2" thick is good, depending on the size of the  part.  You do need to plan ahead a bit here.  If you're going to clamp the template to the stock to be cut, you should make it big enough that the clamps don't get in the way of the router.  I tend to cut a piece of plywood the same dimensions as the stock lumber, and then about a foot longer than the cutting area will be.  Transfer the pattern you drew to the plywood, and cut out the curve with a band saw, jig saw, or coping saw.  A quick way to do this is to use spray adhesive to glue the paper down.  Cut a little outside of the line, and then finish the curve with a sanding drum.  There are cheap sets you can get to go in a hand drill or drill press, or you can invest in a dedicated oscillating sander.  One tip:  larger drums make smoother curves, so don't try to smooth out a 10" long shape with a 3/4" diameter sander.  Take your time and make sure the template is fair and smooth, because every bump will be faithfully transferred to your final work.

Trace the pattern first
3.  Prepare the workpiece.  You should rough-cut the curve with a bandsaw or jigsaw, within 1/4" of the line.  I usually just hold down the template, and trace it quickly with a pencil.  I also make hash marks on the waste side, which seems silly until you accidentally cut on the wrong side of the line because you got in a hurry.  You could skip right to step four, and do all the cutting with the router, but your results will be much better and your router and bit will be much happier if you're not hogging out huge amounts of wood.  If you're using a small router, this is a mandatory step.

Hash marks on the waste side prevent expensive mistakes
4.  Attach the template to your workpiece.  I usually just clamp the template in position.  If some small holes are something that can be dealt with, sometimes it's good to use a couple of small #4 or #6 flat-head screws countersunk into the template.  The router base can run right over them, and they can be used to fasten in the middle of a large or odd-shaped piece.  When deciding how to attach the template, consider the cutting direction of the router bit.  You want it to be working with the grain of the wood as much as possible, to avoid chattering and splitting.

Ready for the router

5.  Cut it!  My weapon of choice for this one is a 3/4" diameter x 2" template cutting bit with a bearing at the top (Whiteside #3023) in a fixed-base router.  Set the height so that the bearing runs along the template and watch the bearing as you cut, not the cutter.  Again, watch the grain direction and try to cut with it.  You might need to climb cut around some curves, which is no big deal if you pre-cut the shape fairly closely.
A big bit gets the job done easily
Ta-da!  I usually leave the edges crisp and smooth from the router, but a quick pass with a roundover bit or hand sanding will make a smooth edge if you want.  Otherwise, there's no more woodwork required.

No sanding required

Tuesday, May 24, 2011

Metal Trough Planters

A couple of years ago, I ran into a woman who was asking how she could get rid of some black bamboo (Phyllostachys nigra) that she'd planted in her yard.  She'd cut it down one year, and it had all sprouted back up.  I perked up because I was at a sale shopping for bamboo when she said it, so we went over and dug up several clumps and cleaned up her patch in trade for about $150 worth of free bamboo.

We planted it in the ground, in big rubbermaid containers with the bottoms cut out, because that was my strategy for preventing escape.  18 months later, and we were ready to completely re-do the yard in that area.  The bamboo came out, we built a new fence behind it, and put it back in the same spot, but this time, in above-ground planters that are sold as livestock watering troughs.  They're heavy galvanized sheet metal, with a handy drain hole and a rolled rim.

This is not a new idea.  We see these planters all the time, but here's what it looked like when we did it.

First off, we leveled off the area, and packed the dirt with a tamper to try to reduce any later settling.  Then I went and picked up a half yard of 3/4-minus crushed rock, and we put down a couple of inches of that, tamping as we went.  The tamping is very important, if you don't want the ground to subside on its own later and ruin your work.  I use a hand tamper that is basically a ten-inch square of cast iron with a handle.  It weighs about 15 lbs, and it's a good workout.  You can also make your own out of wood, or just use a chunk of 4x4 for small jobs.  It's amazing how solid a bed of crushed rock gets after compaction.  The fine bits fill in the gaps between the bigger chunks, and it makes for a very sturdy surface.  Stomping with your boots isn't really a substitute, because you need to deal more of a blow than your feet can handle.



We set the troughs in place, and made sure they were level with each other and sat nice and flat.   It took a few iterations of wiggling the planters, and then removing them and adding rock and raking and tamping, but this is the only chance to get it right.  Once we were happy with the position, we put a bit of rock in the bottom for drainage, and then filled the first foot with fill dirt (very little organic material), and then topped it off with about 16 inches of mixed compost and soil.  Our neighbor helped us heave the giant bamboo root balls into the planters and that was that.



A few weeks later, several new canes have sprouted.  Hopefully, if I can keep the sun from roasting the containers, the bamboo will be happy here and provide a nice backdrop for the yard.

New Back Fence

I came up with this fence design in 2005, and building it was the first project we did when we moved into our house.  I wanted it to look good from both sides, and of course be reasonably solid.  It's basically a set of horizontal rails that are used to sandwich the pickets.  For a six ft. tall fence, I use three pairs of rails; 1x6 at the bottom, 1x4 in the middle, and 1x2 at the top.  The rail configuration and picket width and spacing can be varied to change the style of the fence with little effort.  Everything is held together with screws, which means it's pretty easy to take apart and repair or modify, and pre-drilling every hole means no splitting.  The panels are held to the posts by custom-made aluminum brackets, which are strong and non-corroding, while being invisible from one side and low profile from the other.

For the design I'm building here, the pickets alternate between full-width (5-1/2") and 1/3 width (1-3/4") and have a 3/4" gap between each one.  I like this layout for fences that don't require the most privacy, and it makes a better wind screen than a solid fence.  Yes, the gaps improve the wind performance.  Go ask a physicist why.

So here's a step-by-step guide:

1. Set the posts.  We have relatively solid clayey soils, so a simple protocol of digging a small hole and setting the post in concrete is plenty.  I set an 8 ft. 4x4 (either pressure treated or quality cedar) about 21 in. down.  That leaves 6'-3" above grade, enough for the post tops to rise an inch or two above the top of the fence panels.  I always install the two corner posts first, let them set up, and then stretch a piece of mason line between them so that I can line up the remaining posts to that reference.  No need to fill the hole right to the top.  Even if you skip the curb (next step) you don't want to look at the top of a concrete plug around each post, so leave the surface a few inches below grade.  Do slope the top of the concrete away from the post, however, to prevent water from pooling against the wood.

2.  Pour a short concrete curb at the base.  We just did this for the latest rendition of the fence across our north property line, but I'm going to go back and add this feature to some of the other segments.  It prevents weeds and animals from crawling under, keeps the lowest wooden parts of the fence away from the soil, and makes for a much neater appearance.  Plus it's easy and cheap.  Scrape off three or four inches of soil (frost concerns are minimal to nonexistent here) and build forms by simply screwing 2x3's on each side of the posts.  I put the tops about 2" above finished grade, and the bottom about 2" below.  Make sure they're level across the width, and you can make them level or at a slight angle to follow ground contours between the posts.  Mound soil along the outside of the forms to keep them from bowing out when you pour the concrete in.

Filled and screeded flat.  Note the water that floats to the surface.  Do not disturb at this stage.


When you fill the forms, work it into all the corners and vibrate it a bit by hand to get the bubbles out.  Then just screed it flat by sawing back and forth with a scrap of lumber.  A layer of water will appear at the surface, and then disappear after 30 minutes or so.  At that point, the setting process should be far enough along that you can put nice curved edges on the top of the pour with an edging tool; just run it back and forth for a much improved final product.  Unscrew the forms and rap them gently with a hammer to knock them loose after at least several hours.

Time to remove the forms

 3.  Make and install the aluminum brackets.  I start with aluminum angle, 1"x1"x 1/6" thick.  You'll need one for each end at each set of rails, and I cut them a little shorter than the rail material.  So, 2 ea. 1-1/4", 2 ea.  3-1/4", and 2 ea. 5-1/4".  Drill two screw clearance holes (just one on the 1-1/4" brackets), 3/16" in diameter, on each side.  I center the ones that will be screwed to the posts, and put the ones that will go through the fence closer to the outer edge.  That way, the screws won't be as close to the rail ends which will reduce the risk of splitting.  Next I establish the top of the entire fence, usually by pulling a mason line level and marking each post.  If the fence is built on a slope, I like to stair step each segment, but there's nothing wrong with building it at an angle, either.  Come down 3/4" to allow for the top cap, and another 1/8" to allow for the bracket width being less than the top rail, and that gives the location for the top of the little top bracket.  Attach the bracket to the post, 3/4" from the edge, with a #8 x 1" stainless steel pan head screw.

A 3-1/4" Middle Bracket
For the middle brackets, I just measure down some pleasing-to-the-eye distance and install all the brackets there.  Usually about 14" to 16" looks good to me.  For the bottom brackets, I measure up from the ground 1-1/4" to the lower edge of the bracket.
Lower Bracket Installed - note the round, tooled edge on the curb
4.  Install the three rails on the "ugly" side.  These are the ones that will have all the screw heads visible and also the side the brackets will be visible from.  It's also the side you can take the fence apart from, so that's a consideration.  They'll have to fit snugly between the brackets and screw heads, so I usually just hold the lumber up and mark the length in place.  Screw them to the brackets with little #8 x 1/2" screws temporarily.

5.  Install the pickets.  This is the monotonous part.  Measure from the bottom of the lower rail to the top of the top rail, and cut the pickets about 1/2" shorter.  I use a Quick-Grip clamp, adjusting the height 1/8" or so below the top of the upper rail, and clamping at the middle rail.  Use a bit with a countersink and drill a pilot hole through the rail and picket, in the center of the picket.  Drive a 2" Deckmate screw through the rail, and just barely through the picket.  It really helps to have two drills for this.  Move the clamp to the top rail, and repeat the process, making sure that the picket is vertical.  Then clamp the picket to the bottom rail and put a screw in there.  I use a spacer of some sort to keep the gap between each picket consistent, and check every third picket or so with a level to make sure I'm staying plumb.

Picket Installation
The last picket will be some odd width, and sometimes not even the same at the top and bottom.  Just measure the gap at the top and bottom, mark those widths on a picket, draw a line between them with a straightedge, and rip along the line with a circular saw.  You may want to actually measure out and mark the location of each picket on the back of the rail, to make sure you don't wind up with some odd gap when you get to the end.  A 3/4" wide picket is going to look mighty odd...

Only use one screw at each position per picket, and don't space the pickets too close.  The pickets will change width quite a bit over the seasons.  Wet pickets installed with a 1/8" gap might have a 1/2" gap in the middle of a dry summer.  Two points of attachment means the pickets will tear themselves apart, and tight gaps won't allow for expansion, again resulting in self-destruction.  If you really want a tight privacy fence, you could use a router or dado blade to shiplap rabbet all the pickets, giving them a way to overlap without colliding.  I did that for a gate, but it would be a lot of work for a long fence.

6.  Install the other three rails.  Cut them to length, and get a helper to stand on the other side of the fence to hold them in place while you drive the screws the remaining way home.  You can use a clamp on the top rail, and maybe on the bottom rail, but it's best to just have someone push against you while you drive the screws in the middle rail.  Be sure that the forces balance, and don't tighten the screws with the fence bowed because it will want to stay that way.  It's best if the lumber is a little wet, because unless you want to remove, drill, and reinstall all those screws, At this point, remove the little 1/2" screws holding the rails on, and drill and install #8 x 2" stainless pan-head screws through the entire assembly.

7.  Finishing touches.  I put a 1x4 cap across the top, fastening it with four screws.  This keeps rain from soaking into the ends of the pickets, and lends lateral strength to the fence.  Trim the tops of the posts all at the same height from the top rail.  I draw a line all the way around the post with a carpenter's square, and follow it with a handsaw.  A post cap finishes off the job.  I usually attach it with a couple of screws right through the top, because it's easy to remove if damaged, and the screws won't fail like some of the adhesives I've tried.

A similar fence I built on a slope

A bench wall planter for the yard

The last two summers have been spent working on the inside of the house, remodeling the rear addition.  The yard was totally ignored, and now it's time to set that right.  A few months ago, we tore out the short chain-link fence that ran along the north boundary of our property and replaced it with a six ft. cedar fence. Then we installed a pair of 2' x 2' x 6' galvanized troughs and planted some black bamboo in them.  The idea is to grow a screen from the east wind and also block the sight line from the street into the yard and kitchen.

Our yard doesn't have a lot of full sun growing area, so I'd thought about putting in some little raised beds somewhere back in front of the bamboo tanks.  Over a few weeks of mocking up with stakes and boards, we decided to build a big, solid project that would provide some hardscaping, a planting area, and eventually a vertical growing structure for maybe a kiwi vine or something similar.

Basically, it's a 12' x 3'-6" raised bed, 16" high, with 6" thick masonry walls around three sides, and treated timber walls across the back.  The masonry walls will be topped with a 12"-16" wide cap so that it provides a seating surface.  Three or four tall posts across the back will support the timber walls and also provide for a trellis of some design tbd.

Wednesday, February 23, 2011

Low-cost Raised Beds

When we first bought our house, we were pretty strapped for cash, but I still wanted to put in a couple of raised garden beds and get some vegetables going right away.  I was building a fence at the time, and had some cedar fence pickets lying around that were too ugly to use on the fence.  So I tacked some together to make some raised beds.  Six years later, they're going strong, so I'm sharing this idea.  I wouldn't bother building anything more sturdy and expensive unless they needed to be much deeper for a really wet site.

For each bed you will need:

Three fence pickets.  You want 1x6 square top pickets, 6 ft long.  Don't mess with any nasty treated wood or try to do with plain pine or hemlock boards.  You want red cedar, and the ones with the darker red and brown colors are the most rot-resistant.  They should cost anywhere from $1.25 to $2.75 each, depending on the grade and where you get them.

Two 1 ft stakes, so get a couple of feet of cedar 1x2 material for each bed you plan to make.

Eight #8 x 2" and two #8 x 1-1/2" screws, flat head if you have a countersink, otherwise pan-head.  Get them in stainless if you like, but any decent galvanized or 'gold' coated will be fine.

Cut one of the boards into two equal lengths, about 3 ft.  These are the ends.  The uncut long boards are the sides.  Important:  Cedar tends to split, so predrill and countersink the sides, about 1" in from each end.  Screw the sides to the ends.

Put the screws an inch or so in from the end of the board to reduce splitting
Sit the frame on the ground where you want the bed to be, and drive a 1 ft. stake at the midpoint of each side.  If the soil is wet and soft, this should be easy and you probably won't even need to sharpen the stake.  Put a screw through each stake into the side of the bed frame, about an inch down from the top.  The stakes will keep the relatively flimsy boards from blowing out under the weight of the soil inside the bed.
Reinforcing stake at the middle of each long side

Now fill the bed with a nice mixture of compost and soil, and stir in any bone meal, lime, or other amendments you might need, and get gardening.

Two of my beds.  Herbs in the back, berries in the front (and a garlic escapee)

Thursday, February 3, 2011

Mission Finish

I looked at a bunch of recipes for a "Mission" finish for the TV stand project I've been working on.  I like to finish some parts before assembly, so I don't have to worry about glue squeeze out, and also because it's usually a lot easier to apply finish to the individual parts instead of trying to work it into all the corners of assembled furniture.

The first finish I tried was a gel stain.  General Finishes "Java" was recommended in some Popular Woodworking book or article.  It looked like a nice, easy, almost single-step finish, so I picked up a can at a local Woodcraft store, and tried it on a sample board.  It was too dark for my tastes, and more importantly, it colored the wood VERY differently depending on how the surface was finished.  Surfaces smoothed with a hand plane were darker and the stain absorbed differently than sanded surfaces. I'm sure I'll have some of each. Yikes.




Another Popular Woodworking finish recipe I found called for a layer of oil stain (Olympic "Special Walnut"), followed by a coat of Watco "Dark Walnut" followed by amber shellac.  As I am lazy, I skipped the first stain, and used Watco "Black Walnut."  I think it looks pretty good.  Watco is super easy to work with, and gives a little more protection than stain alone since it contains some varnish resin.  The color went on the same on sanded and planed surfaces, and it gives just the right amount of contrast to the ray flake in quartersawn oak for my tastes.  Here are some parts from the end panel assemblies.

I'm not sure what clear protective finish I'll apply on top of the Watco.  I've never used shellac before, so that's a little scary on such a big prominent piece of furniture.  Polyurethane varnish has always been my topcoat of choice, and it's tough, but also not very repairable.

Wednesday, February 2, 2011

Lutherie 101

Take a piece of string or wire and clamp it between a couple of points.  Pull it somewhat tight.  Now, put some energy into it, by hitting it or plucking it, or blowing on it.  It will naturally vibrate at a basic frequency determined by the length, tension, and diameter.  (that third factor is technically mass per-unit-length, but if the wires are the same material it comes down to diameter)  Shorter = higher frequency, tighter = higher frequency, and smaller diameter = higher frequency.  Then you make a way to clamp the wire at various points so you can change the length on the fly, and now each wire can make a series of frequencies depending on where it is clamped.  Get a few more pieces of wire, of different diameters, and tension them next to each other and you can make an arbitrarily wide range of frequencies. That's it!

Considering string instrument construction, there's a little terminology to start with. The two fixed ends of the wire are the nut (at the top) and the bridge (at the bottom). Strings are usually anchored at fixed points below the bridge, and wound around adjustable posts above the nut so that the tension on each string can be adjusted for tuning. The in-between clamping points are commonly little metal bars called frets, and the strings are pinched just above each fret. The open frequency of a string is defined by the nut-bridge length, string diameter, and tension, and the subdivision of each string's frequency is determined by the spacing and location of the frets.

Now for the relationship between frequencies, notes, and fret locations. Modern western music is dominated by a tuning system of 12 evenly-spaced notes per octave, based on a reference frequency of 440 Hz. Octaves are defined as a doubling of freqency, so an A note in the 4th octave (A4 = 440 Hz) is twice the frequency as an A in the 3rd octave (A3 = 220 Hz) which is twice the frequency of A in the 2nd octave (A2 = 110 Hz). The spacing between each individual note fits into the logarithmic pattern, so that the difference between any two notes is a factor of 2(1/12) Hz. - the frequency doubles every 12 notes. The first note in each octave is C, for whatever reason, and the twelve notes are:

C, C#, D, D#, E, F, F#, G, G#, A, A#, B

This is referred to as the chromatic scale. The # symbol means "sharp", but all the sharp notes are exactly the same frequency as the next regular note's "flat." Thus D-sharp is the same note as E-flat, except for the two notes that don't have a sharp: B and E. This convention makes little sense to me, but it's just the tip of that iceberg. Each note corresponds to a key on a standard piano keyboard. Here's one octave of keys, with a B and C on either end of the next octaves shown for reference.


Each note also corresponds to one fret on a guitar, so if you have a string tuned to a D, each fret position will play D#, E, F, F#, G, etc. down the fretboard. Say that the nut-bridge distance is 26 inches, and that D is D2. If you put a fret at 13 inches from the bridge, it will play D3, the same note an octave higher, because it is 1/2 the length.  If you put another fret at six and a half inches, it will now play D5, two octaves higher than the open string, because it's now 1/4 the length. Few stringed instruments actually have a full two-octave range, but many are close.

Another option is a diatonic scale, where you have only seven notes per octave.  This is mostly on some old timey instruments like mountain dulcimers, accordions, and harmonicas. They are eight of the same exact notes as a chromatic scale, just missing some to leave just what is called a major scale.  That is the familiar do, re, mi, fa, sol, la, ti, (do) thing. If the string is tuned to a C, the notes are the same as just the white keys on a piano, so you can't play any of the sharps.  That works ok for many simple tunes, and traditionalists like it.

The physical distance between fret positions is related in the same way the notes are, by a factor of 2(1/12) which I'll refer to as a to simplify the upcoming formula. Given the total nut-bridge length as L, the distance to a given n-th chromatic fret is: L - (L / an).