Archive for the Acorn House Category

No fret frets

Posted in Acorn House on November 18, 2012 by acornhouseworkshop

Fretting this fingerboard is a bit more involved than past builds due to the fretboard binding. Instead of the fret tang (the barbed tongue that holds the frets in their slots) extending all the way out the side, they must be trimmed where the fret will extend over the binding. This means a lot of prep work before the relatively easy task of hammering them in can take place.

First, I like to add a fingerboard finish to the radiused and sanded board, especially with cocobolo. This seals the wood and provides a nice smooth feel. Of course, before any sealing can take place, the slots have to be cleared of all of the sanding dust that has accumulated during the radiusing process. This requires a special tool that can get in the narrow slot without widening it. Then a couple coats of the finish is wiped on and buffed to a satin sheen.

Since each fret will have to be sized for length and trimmed, a staging board helps keep the frets organized. Then comes the fun (insert sarcastic comment here!) of trimming the barbs to the correct length. They have to be long enough to hold the entire fret firmly in its slot, but still leave enough of a gap so that any seasonal contraction of the wood doesn’t push them through the binding. Using the EVO fretwire, which is harder and longer lasting than conventional nickel-silver wire, means using a bit more force to clip them all, but with the right tools, even that can be done. (I just hope I’m never asked to use stainless steel fretwire. That just eats tools for breakfast!)

After trimming the tangs, any rough remnants of the cut need to be filed flush. Then, after one final slot cleaning, the hammering can begin. This is the easy bit. The cocobolo holds the frets nice and tight, with no need for glue. All you need is a good support for the neck and a firm hand.

When I get to the fingerboard that will extend over the guitar body, extra support must be used under the hammer to avoid snapping the extension.

The ends are clipped close to the bindings and then filed flush. (Also not a task I enjoy. I much prefer to work wood rather than metal.)

That’s it for the neck, until its ready to be attached to the body for the last time. Then the frets will be levelled and the ends dressed. (In a nice casual ensemble!)

A little necking

Posted in Acorn House on November 8, 2012 by acornhouseworkshop

With the head shaped, the next step is to bind the fingerboard. Since the guitar body will be osage orange with cocobolo binding, we decided on a cocobolo fingerboard with osage orange binding.  After cutting the fingerboard to length and the tapered width (according to the nut width and the join at the 12th fret), first I curved the end that will overhang the soundhole, and curved a strip of OO to match it. That’s glued and trimmed flush, then the side strips are glued on.

Then, the sides are flushed with the ends and the whole bound fingerboard get a trip through the drum sander to bring the bindings level with the top and bottom. Then the fingerboard gets glued to the rough neck, with the truss rod in it’s slot. After the glue cures, the neck is taken to the router and, using the flush trim bit, the sides of the neck are brought to the width of the fingerboard.

It’s now time to work on carving the neck. This is one of my most enjoyable parts of the build; every stroke of the rasp has an immediate effect. There’s no glueing, its all shaping the neck, checking it, making adjustments, testing again, until finally, you’ve gone from a square block that would be very uncomfortable to hold, to something that fits the hand to a tee! One thing that made this neck especially enjoyable to carve, was the purchase of a specialty vise to hold guitar necks. It was so easy to hold it secure, work on any part of it, shift positions, reclamp, etc. Previously, I’d had to clamp it to the edge of my bench and work on one side at a time. Changing position to work on another part became a major production! This was a piece of cake as I attacked the neck with spokshave, rasps, and sandpaper.

After the initial shaping, I was able to meet with my client, so he could get a feel for the neck, and see how it was fitting his hands. On the whole, he was pleased, noting just a couple of small spots to address. That’s the benefit of a true custom guitar; you’re not selecting from a short list of options, everything is tailor made just for you!

Next, I did an initial radiusing of the fingerboard to a 12″ radius. Then I marked out and drilled the holes for the mother of pearl position dots. After they were glued (with gel CA glue), I did the final passes with the radius block, to bring everything to a nice silky smoothness, leveling the dots at the same time.

Then I marked, drilled and glued the black side dot material into the binding. After leveling, its ready for a final sanding and frets.

That’ll be next.

Getting Ahead

Posted in Acorn House on October 15, 2012 by acornhouseworkshop

I’ve talked about the process of building the neck before, but I’ve added a couple of tweaks to the process (and a thunk), so I’ll give it another go. In the good old days, when the forests were endless and wood was cheap, the necks (and heads) would be made from one solid piece of wood; a couple of bandsaw cuts, some shaping, and you’re done. Unfortunately, this results in a considerable amount of waste. Now, with the rain forests becoming depleted, a number of species on the endangered list, and the cost of wood becoming dearer and dearer, it becomes more and more important to conserve as much as possible. So, necks are usually made from multiple glueups.

For the commissioned guitar, the customer wanted a mahogany neck, and I found a very nice board of reclaimed Honduran mahogany that had been rescued from the bottom of a river, where it had lain for decades. This was an ideal choice in a couple of ways. One: because of the reclaiming process, the wood is incredibly dense and stable, easily the heaviest mahogany I’ve ever encountered. Two: the customer is a heart transplant patient and intends to use the guitar to help others as they wait for new hearts, so the recycled wood fits in with the theme.

The first step was to make the basic sandwich of two pieces of the mahogany (cut to minimize waste) with a creamy maple filling. (Shown here with the maple neck sandwich of the second build.)

Next, the top part is cut off at a 15° angle and, after planing the scarfed surfaces flush, the two pieces are glued together with a scarf joint to provide the head. This also ensures that there are no short grain areas in the head that would be prone to break from the tension of the strings.

Since the width of the neck assembly is too narrow for the shape of the headstock, wings must be glued on to provide the extra width. The waste material of the original neck stock is used. This also helps to further reinforce the scarf joint.

The final pieces of the puzzle are the headstock overlay and underlay (a new element with this build). Aside from providing the contrasting wood to house the inlays, these pieces further strengthen the head joints, with plenty of long grain to resist the strings’ pull. I used cocobolo for the overlay and osage orange for the underlay.

With the sandwich all glued up, its now time to cut the headstock to profile. This headstock has a very special element, an inlay by Jimmi Wingert, a well known artist who usually is providing inlay for her mother’s guitars, Kathy Wingert. The customer had commissioned her to inlay an image of the “Tinman”, from the Wizard of Oz, which, because of his own search for a heart, had become his nickname.

This inlay upped the ante for the next step, since any slips could ruin the artwork (and cost me a considerable amount of $!) I cut the outline of the head at the bandsaw, and then dutifully taped the pattern to the headstock using double sided tape. I set up the router table with a pattern bit and started on the first side.

Maybe it was the cool morning temperature, maybe it was the fact that I had used the pattern to rout a number of shapes previously and the glueing surfaces had been compromised, but as I reached the end of the first side, I had the sickening feel of the pattern slipping. After a string of expletives, I tore the pattern off and surveyed the damage. A nice divot that, THANKFULLY, stopped shy of the inlay. A disaster, but not a complete disaster. I would have to rework the headstock shape to a thinner waist to get past the slip, but it was still useable.

I consulted with the client (ever so understanding) and layed out the tuner holes carefully (they were tight, but they did fit) and prepared a new pattern. This time, I would use the tuner hole position to screw the pattern to the headstock before routing. (Since I had used the old pattern for both guitar and bass, I hadn’t done this before, and the tape had held before. It only takes one time!)

This time, the routing went smoothly, with no problems. After drilling the pilot holes to the final size for the tuners, I could finally breath a sigh of relief. A couple of thin coats of blonde shellac to seal everything, and I can turn my attention to the fingerboard.

Both Tinmen had a terminal scare, but both emerged, hopefully for good!

In a Bind!

Posted in Acorn House on September 26, 2012 by acornhouseworkshop

One of the skills that has never given me any trouble in my luthiery odyssey has been hot pipe bending. The only time I had any problems, was with using stock that was too thin and had a lot of runout. Bending bindings, especially, seemed a piece of cake; even curly maple, which is reputed to be a bear.

So when I decided on the bindings for the current two builds, I didn’t give it much thought. The client specified cocobolo for his, and I decided on ebony for mine, being a nice accent to the myrtle. I got the binding stock and chugged along on the build. I was a little nervous about the added bends around the cutaway, but that just means two extra curves. When it got time to bend the binding, I fired up my pipe and prepared my wet cloth and spray bottle. (I have been using a new technique after seeing famed Luthier Flip Scipio wrap his hot pipe with a wet cloth to provide constant steam. It really works.) I started with one of my ebony bindings, and everything went nicely, it bent like butta! I got that one in the mold to dry and started in on the next one. No sooner had I started then I could see a split starting to open up. Sigh! I grabbed another one and…ARGGH! The same thing happened. I tried the cocobolo and got a couple of sides bent, but the third one decided to join it’s fractured ebony brethren. I took that as a sign and shut everything down.

When I got back to it, after a couple of days, I managed to get one more cocobolo bent, but the remaining ebony blank also began to split almost immediately. I was done. Unfortunately, I hadn’t ordered any extra (that stuff adds up, ya know!) I knew I would be going up to the Athens area in the next week or so (which actually turned into a month, plus), and I would get more then, this time getting some extra.

(If you look closely, you can see the wood beginning to separate on the curves.)

I also did a little reading on ebony and, lo and behold, its one of the finickiest woods to bend. Because it has such a fine grain structure (and is so dark, ebon-like, almost), its hard to see when the grain is running out or not. (Grain runout means that the grain runs at an angle instead of parallel to the length, making it more likely to split during bending.)

When I finally got the replacement blanks (with some extra!), I went back to the bending iron. I was able to get the rest of the ebony sides bent with only one breakage (and that one just snapped completely), and the final cocobolo side.

With the ebony, if it was going to break, at least it did it on the first bend. Otherwise, it bent beautifully. (The one cocobolo that broke I think did it in sympathy with the ebony.) I may have to do a little touch up bends, but essentially done and dusted! Now I know to charge accordingly for any future builds, not just for the expense of the wood, but to cover the inevitable breaks and the extra blanks needed.

Just make sure there are no children around when your trying to bend ebony, otherwise you’ll surely need to be bound, and gagged!

Bracing!

Posted in Acorn House on May 21, 2012 by acornhouseworkshop

The two builds this summer will be slightly challenging because, while they will both be small jumbo guitars, using the same molds, one will be a 12-fret design using a 25.5″ scale (customer specs), while the other will be a 14-fret design using a 24.75″ scale (my preference). Btw, 12- and 14- fret refers to the fret where the neck joins the body. Before the 1930’s, most guitars were 12-frets, nowadays, most guitars are 14-frets, but there is a growing demand for the earlier design, especially among fingerstyle players. In addition to these design differences, the bracing patterns are different. In addition to moving the soundhole and changing the x-brace angles to accomodate the change in the bridge location for the 12-fret  guitar, the custmer wants a symmetrical tonebar brace pattern similar to one used by Larrivee guitars, and similar to the one that I use in “The Beast”, illustrated in an earlier post. I will be using a typical asymmetrical lower tonebar design for my guitar. Both guitars will get a parabolic shape to the braces, rather than a scalloped shape.

The braces are milled from well quartered sitka spruce stock, the bottoms are arched as needed, and each brace gets glued into place. After they have set, I carve the to reduce their mass, while leaving as much height as I can for maximum strength. My favorite tools for the job are my 1/2″ Stanley 720 paring chisel and a Chinese style ebony finger plane.

Lots of curved shavings make me want to get a hamster (although I fear the cats would look on it more as a snack!) When everything is carved, and I am getting a good tone from the top, they get sanded smooth. Maple bridge plate are glued as well, and the soundboards are ready for the sides. You can sees the two different bracing patterns (and some layout lines from earlier incarnations if you look close.)

The diamonds are added for a little extra seam support where there isn’t any brace. You can really see the different soundhole and bridge plate positions for the two different designs.

Compare and contrast!

Rosettes by the bunch

Posted in Acorn House on May 21, 2012 by acornhouseworkshop

Before bracing can begin on the soundboards, rosettes have to be inlayed. (Its much easier working on a flat surface than a slightly arched one that doesn’t lie flat.) I use a small router with a circle cutting base and the appropriate sized router bits to do mine. For the commissioned guitar, I am using bloodwood and blackwood to divide the rosette into four quarters, representing the four major parts of the heart. (The gentleman commissioning the guitar is a heart transplant recipient who goes by the nickname ‘Tinman”. He intends to use the guitar to encourage others going through a transplant.) After sketching out my design, I milled the wood to approximate shape, and used a chisel to fit the pieces tight together.

These then get glued into the routed channel with liquid hide glue.

Then, to frame the woods, I rout a thin channel on either side and glue in some black-white-black purfling strips. The purfling strips are purchased premade using a dyed cardboard type material that is flexible and stays white and black no matter the finish or age. After glueing these get scraped flush. Then everything gets sanded smooth. (There’s a couple of areas on the blackwood that are depressed, and there is some glued reflecting back in the picture. These will disappear after the finish sanding and finishing process.)

It doesn’t show as well in the pic due to the lighting, but the bloodwood is truly vibrant against the whiteness of the Italian Spruce. (The rough bit at the top will be covered by the fingerboard, so its a good area to make test cuts with the router.)

The second rosette, which will be for my personal guitar, will have a fairly standard design of paua abalone in between two rings of purfling. The purfling channels are routed and the the purfling is glued and then scraped.

Then a channel for the abalone is routed and the abalone pieces are prepared. They come pre arched, but the ends need to be mitered to provide a seamless ring with the 15 pieces of abalone. This is done at the sander with a simple jig. When everything is ready, the pieces are selected to minimize any abrupt changes of pattern between pieces. The abalone and border purfling are glued in together using extended cure epoxy. Then everything is scraped and sanded flush to a sparkly shine.

Brace yourself for what’s coming next!

Paradox

Posted in Acorn House on April 30, 2012 by acornhouseworkshop

I’ve begun my latest guitar build(s). I’ve been commissioned to build a small jumbo sized guitar for fingerstyle playing. At the same time, I’ll be working on a second one for my own use, and as an example to show prospective customers. These guitars will also be adding to my skillset, since they will have a Venetian cutaway. (A Venetian cutaway is a cutaway with a rounded upper bout, allowing easier access to the higher frets. A Florentine cutaway has a sharp angle to the resultant ‘horn’.)

After making the molds, (which because of the cutaway design, require two different sides), I got the bending pipe heated up and ready to go.

The customer ordered a back and sides of osage orange, and I will be using Oregon flame myrtle for mine. In order to warm up, I bent the myrtle sides first, starting with the non-cutaway side. No big problems, although you do have to be careful when there is a big curl in the wood not to let it bend on an angle, which it really wants to do. Got it bent and clamped in the mold fairly quickly. The myrtle bends much like walnut, except at the curly bits. The cutaway side didn’t really pose too many problems, it just takes longer. Because of the extra bends, reversing on each other, working on one curve tends to start to unbend the opposing curve. So there is a lot of redoing involved. Once its clamped and dried in the mold for a few days, it finally sets up. Next was the osage orange, a wood I hadn’t worked with before. It bent relatively easily, with no figure its curves came out very smooth.

(It might make a good dye, though. While working with the wet, steamy wood, my hands took on a distinctive yellowish hue that took a couple of washings to get out. “They call me Mellow Yellow…(quite rightly)”)

Taking the OO sides out of the mold, there was a bit of spring back, so I’ll have to do some touch up bending before attaching the top.

Next up was thicknessing and glueing the soundboards. Mastergrade Italian red spruce for him, and ‘Bearclaw’ sitka spruce for me. Nothing new here, I used a simple jig to clamp the thin (0.115″) boards. Supporting one side with nails and a boarder, I tent the two halves up 3/8″ and nail in the opposing support.

Pushing down the glued boards provides just enough clamping pressure to the two sides without the thin wood bowing out.

A little weight on top helps keep the joint aligned and flat.

After an hour, I scraped the squeeze out before it completed dried and left them to cure.

You can really see the ‘Bearclaw’ figure ready to pounce from the sitka spruce top. I can’t wait till I get the finish on it (but that’s a bit of a ways to go.)

Next up will be outlining the small jumbo pattern and layout the braces. I’ll be doing two different layouts since the customer wants a 12-fret model, and I’ll do a 14-fret design on mine.

I definitely need to find a better name for this style other than “small jumbo.” No paradoxes allowed at Acorn House!

Really fuming, now!

Posted in Acorn House on April 16, 2012 by acornhouseworkshop

I recently acquired a 1920s etching by the English artist George Marples. With the subject matter (an old mill) and the time period, I decided an Arts & Crafts style frame would be appropriate. I got a nicely rayed piece of QSWO out of my stock and proceeded to mill and joint. I didn’t want to do something too elaborate that would take away focus from the art, so I didn’t try to do a Green & Green style frame, settling for a simple lapped joint frame with ebony plugs. (Well, African Blackwood, really. Tomatoes, tomahtoes.)

When it came time to finish, I found that I didn’t have any Walnut Danish oil on hand (my normal go to A&C finish), and the closest available was an hour away. So, not having time to make the trip, I read up on the technique of fuming oak with ammonia, a period appropriate method. The ammonia fumes react with the tannin in the oak, causing it to darken. Traditionally this is done with aqueous ammonia, a very strong concentration that is highly toxic, and of limited availability. Not something I really wanted to mess with, not having the necessary safety equipment. But, some people have been experimenting, lately, with using household cleaning ammonia, janitorial strength preferred. Stopping by the local hardware store, I found some “Extra Strength Ammonia.” Very generic, no strength concentration listed, and cheap. I decided to give it a go.

I set up a tent outside using a plastic painting tarp and some loose boards and bricks. With the wind to my back, I set the frame inside with a tray that I filled about halfway with the ammonia. Honestly, I didn’t even get a whiff of the ammonia smell, so I was wondering just how strong it really was. The big difference between household ammonia and the stronger stuff is how long it needs to be exposed. So, I left the frame in the tent for a couple of days, checking it periodically.

After the two days I untented to check, and possibly refresh the ammonia. The bright sun was deceptive, but it was decidedly darker, although grey rather than brown (which I was expecting). It had worked! (assuming the finish browns it as advertised.)

I applied 4 coats of my favorite satin oil/varnish, and it immediately showed its true colors, a rich nutty brown. Now I could really see the benefits to fuming rather than using stains, dyes, glazes, etc. to imitate the fumed look. Some of the “fake” methods do bring out the medullary rays better, BUT, they lock in the color, In the fumed oak, the rays have a chatoyance that is lost under stains and dyes. There is a depth to them and, depending on the angle of viewing, they change from a light brown ray against the darker field to a dark brown ray.

That’s the magic of fuming. Its not just the color.

To finish up I glued in the polished plugs, matted my etching and used a point driver to secure the mat, art, backer and glass in the frame. Ready for hanging.

Even though fuming a large piece would be more of a pain, building a big enough tent, I don’t know if I can ever go back to a stained A&C finish. That’s got me fuming!

What a difference, a day makes…

Posted in Acorn House on March 25, 2012 by acornhouseworkshop

I got a commission last year to build a jewelry box for a customer to give to his wife for X-mas. I was planning on following my previous earring box design, using a red malle burl for the lid, instead of spalted maple. I was going to start work on it as soon as the semester finished up, leaving me plenty of time. Of course the best laid plans, etc., etc. During finals week, I came down with the flu and even after I shook the major symptoms, I still had the lingering blahs. I tried to do what I could, started to pick out the wood, and got so far as to shape the red malle lid. It was a turning block that had developed some major checks in it, so I had to change the shape of the design. While milling the cherry for the sides, I kept on running into boards that, after planing, didn’t really look that good; definitely second quality. Also, the adapted design didn’t seem to be working, it just didn’t seem right. This, plus the blahs, plus the cold workshop (which, if I kept the overhead space heater on, got it up to a balmy 40°), plus the other presents I had to make, and the rapidly approaching deadline, led me to an unpleasant, but unavoidable conclusion. I emailed the client to let him know that I didn’t think I would be able to finish on time, with anything that would be worth giving.

Luckily he was understanding (I had told him early enough so that he could make other arrangements), and made a new deadline of March 30th, their anniversary. Cut to the beginning of March. The weather had turned unseasonably warm, I had shaken any lingering effects of the flu and had come up with a new design using the aborted red malle lid in a new way with curly maple instead of cherry. Everything seemed to flow. The design felt right, with each step in the build, I was able to figure out the best way to tackle it, and the execution was coming easy. (Oh there were still a few hiccoughs along the way. After finishing, when I went to put the hinges back on for the last time, I had to try four different orientations before finally getting the screws holes to line up on every leaf.) I got the jewelry box finished and shipped with days to spare, resulting in a happy client, and a happy Acorn House.

Creativity, like invention, may be 1% inspiration and 99% perspiration, but that 1% is critical for any new work. (And, its tough to perspire in a frigid workshop!) Inspiration can be a fragile creature at times, but when its feeling up to snuff, watch out! What a difference, indeed. It may need more than 24 hours sometimes, but you’ll know when its enough.

WIA 2011 – Final Ruminations (thoughts have been overdone!)

Posted in Acorn House on October 26, 2011 by acornhouseworkshop

Now that I’ve recovered from Woodworking in America, (and recovered from catching up at school), I thought I’d wrap things up.

My favorite single session has to be Graham Blackburn’s session on using traditional planes for jointing. It was really more than just jointing, he talked about his philosophy on using traditional tools, as well as how to set up and best use various types of planes, both wooden and those new fangled iron and bronze types. Through it all, he talked about the fulfillment of using tools that his forebears had used an hundred years ago; and the fact that, with care, his descendants may still be using the same tools an hundred years from now. The fact that these tools are relatively simple, with a minimal number of parts, means that they are easily fixed and tuned; and that, as woodworkers, repairing wooden planes should be right up our alley! The electron pushing tools have a much more limited lifespan, and, as they get more and more complex, the ability for an average woodworker to handle any major repairs by themselves will be less and less. How many of us, if any, would be able to repair a malfunctioning “flesh detection” technology in those table saws that offer it? That, already, is pretty much a factory repair. (Think how many computers are in the modern automobile, compared with cars from only 30 years ago.)

But, most of all, he showed just how easy, and more to the point, how well, these old tools work. They were designed, and perfected, over many years to do a job, and that development shows, when you know how to use them!

For the overall speaker, (aside from Graham), my next award goes to Jay van Arsdale, and his series of sessions on Japanese tools and methods. Jay really showed many of us a different way of working with, and thinking about, wood. The fact that most Japanese joinery was never meant to be glued, was an eye opener. I had already known how complex some of the joinery could get, but seeing some of these joints in person, and seeing how they were laid out and worked with chisel and saw, made them more understandable. Even using something as simple as an inkpot to mark all of the layout lines became a useful and practical technique, rather than just a quaint imitation of older times in a faraway land. There is a reason why it is better than a marking knife or a pencil for this type of work on these types of woods. I strongly suggest working your way through all 4 of the videos I posted in my last entry for a better understanding. In addition to seeing how Jay works his way through a joint, from start to finish, he provides a running commentary on many of the reasons behind every move he makes. I should give an honorable mention to the perennial favorite, Roy Underhill. Roy is always an engaging and entertaining speaker, but I fear his appeal is beginning to suffer a bit from overexposure, at least to me. While I enjoyed the 1 1/2 sessions of his that I attended, I had already seen the techniques demonstrated on his show, The Woodwright’s Shop. The full session that I attended an making threads and screws by hand, had been aired not too long ago; and the session on frame and panel joinery that I caught the last half of was shown in this past week’s show; and he had covered those techniques in various earlier shows.Don’t get me wrong, I didn’t regret going to those sessions, I just wish he had done something I hadn’t seen before. (At least OSHA had gotten on his case about not using any safety equipment, so he did have a pair of safety gargoyles while turning.)(Um, his pun, not mine.) I guess that is the problem when you have done as much as he has; it’s near impossible not to repeat yourself eventually. Assuming I attend next year, I may just have to skip his sessions. (Sorry Roy, I know you’re brokenhearted over that.)

The loser(s) of the conference, I have already mentioned in an earlier post, so I won’t rehash it. The only other thing that I would have liked to see was more vintage tool dealers in the marketplace. Last year there were four or five that I remember, this year there was only one.

So, while you are drooling over the ultra expensive latest and greatest, don’t forget to patronize the useful but maybe not so dazzling. It’ll be easier on your wallet, and those dealers will be able to make a living and be encouraged to come back!

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