This Week in Wood » Hand tools

Purfling…what a funny word!

glennth — Fri, 14 Oct 2011 18:45:45 +0000

Purfling is a word that defines material between the binding and the top or back wood on a string instrument. Binding is a word that defines the outer most material surround the top and back wood on a string instrument. The purfling is decorative but the binding actually provides some function. First the binding provides protection for the end grain of the top and back woods and second (though I’ve not seem any testing that verifies this but it sounds right) the binding provides a hard border for the top wood (also called the sound board) for a string instrument which affects the tone waves.

On my 3rd guitar body (a full body, no cutaway), I decided to start with the purfling channel.

In a test board, I cut several channels adjusting the router bit’s depth of cut until the purfling was protruding just a smidge (and yes, it’s a technical term though I’ve also heard skosh). I then pick out a bearing which will provide the channel width to hold the purfling and the binding. In the picture above you can see that for the purfling, I have 3 layers (ebony, bloodwood, and a dark brown wood) The binding is a piece of maple bent to the shape of the guitar with a matching dark brown wood edge for the bottom of the binding. The purfling is so thin that it doesn’t need to be pre-bent.

I then use the tested set up to rout the purfling channel into the back and top of the guitar body. Remember in a previous post, I talked about the channel not being square (this is due to the router riding along the top and back and the top and back are arched ever so slightly). I use an adjustable square to test the squareness of the channel and a small chisel as a scraper to adjust the squareness of that channel.

After a lot of scraping, I finally get the fit to be perfect. After I finish both sides of this guitar body, I’ll work on the 4th guitar body (which is a cutaway model) then it will be time to repeat for the binding channel.

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Purfling…what a funny word!

Rip Saw Bench

glennth — Fri, 30 Sep 2011 13:54:37 +0000

Over the last few days, I decided to build another saw bench. I have already built 2 in the Christopher Schwarz style.

I’ve found these saw benches to be absolutely great…except for ripping. The flared legs get in the way when ripping, especially a narrow board.

So I needed something that didn’t have flared legs and a split top sounded like a good idea. I searched the web for ideas and most of them are similar to what I came up with except that I built my bench from 2×4′s and 2×6′s rather than 1by material. It makes my bench heavier and maybe more solid.

As you can see it has a split top and a side apron. I doubled the thickness of the top so I can drill holes for hold downs and have them actually work. I also put a shelf but made it split like the top so I could rip in the middle if needed.

I spent a bit of time to make sure that the current bench and new bench are level so they can be used together on a long crosscut.

Overall I’m happy with it and think it will serve me well.

Of course, now I have 3 saw benches and really don’t have room for all 3. I’ll have to find a new home for one of the old saw benches.

Panel for doors

glennth — Sat, 24 Sep 2011 18:09:53 +0000

After my last post, I had a nice fail and didn’t correctly determine the length of the rails for the doors. The old adage of measure twice and mark once only works if you have decided the length of a particular item correctly. For this project, I’m not using a plan so my determination was flat out wrong.

It took me a few days to get the rails fixed up and ready for the panel.

Next I needed to size the panels from my glue ups. Sizing was simply but keeping everything square was more challenging and requires a great deal of patience.

My next step will be to size the outer edges of the panels for the groove inside the rail and stiles. I’m going to keep it simple and not do any details on the panel or rail and stiles since this is a shop cabinet. Also, I don’t have any moulding planes so I’ll leave details for the next set of doors I need to make.

As an aside, i got some new shoes today and my wife wondered if I took a picture of them.

This picture is for Kathy!

Tongue and Groove for Doors

glennth — Wed, 21 Sep 2011 23:02:49 +0000

School is well under way for my 2 boys (Xander -12 and Mitchell -10). The beginning of the school year plays havoc with the entire families schedules and that of course means my shop time. I have gotten minutes in my shop since it began about 2 weeks ago. Today, I was able to resume a bit of work on the doors.

I’ve decided to go with a tongue and groove joint between the stiles and rails. You may have read a few posts ago when I was cutting the groove for the door panel and the tongues of the rails. In beginning this process I thought the most obvious tool would be my skewed rabbit plane and yes this is probably the main tool for the job but the thing that surprised me was that I would need a few others. I also used a rabbit block plane, a chisel and a side rabbit plane.

Working across the grain didn’t give the best cut but I was able to clean it up nicely with these other tools.

The result was a nice tight fit that I’m very happy with.

Now I have to cut the remaining rails and get the same fit. This job is much more satisfying than the groove.

Wall Hanging Tool Chest – The Back

glennth — Thu, 01 Sep 2011 14:45:44 +0000

Yesterday, I started on the back.

First step was to rough size the pieces for the back (it wasn’t that rough). I cut to length and ripped to width the 4 pieces I was going to use for the back, all with hand saws. I followed this with squaring and straightening the edges and ends that I just cut. I must be getting pretty good with the hand saws cause this step is getting shorter and shorter every time I do it.

I decided to again do a half lap joint between each board so I began on the dado on the sides. I used a skew plow plane which has a depth stop and and edge guide. This makes quick work of the dado. My first time with this tool had me pressing down and against the piece and I found that my pressure was actually moving the fences which are just pressure clamped. I learned from this that light pressure to guide the plane works great and you get fabulous results every time.

The next step was to cut the dado’s on the end which will fit into the dado’s for the top and bottom back rails where the back gets attached.

For this cut, I needed to adjust the side fence for a wider cut. To fix the first board and adjust it, I used a rabbit plane. After a little fine tuning on the boards, they all fit well.

On the saw till, Iliked the v-groove in between the boards so I decided to do it again. I used a simple block plane to accomplish this.

I’ll finish the work tomorrow and show the results. Next step is the hanging cleats and the shelves.

4th Guitar Neck

glennth — Tue, 21 Jun 2011 23:53:59 +0000

When making a guitar, there are some elements that are put together a bit like a puzzle. For instance, the Neck.

The first step in making a guitar neck is to take a long piece of the desired wood and make an angled cut. The angle is determined based on the angle that you want the head stock to angle back. Most necks (except for Fender and a few copycats) angle back so that there is tension at the nut at the top of the fretboard.

In the picture above, you see 3 necks. 2 are shaped and the 3rd one is just rough and block. You can see the angled headstock. Extra material on the neck board is cut off and glued to the other end of the neck making the part of the neck where it will join the body. Also you can see the center groove in the 2 shaped neck. This is for the truss rod which provides a way to tune-up the guitar and by opposing the tension on the neck which the strings put on the neck. Also on the shaped necks, you see that the headstock has a laminate glued on.

Once the headstock laminate and the groove for the truss rod have been completed, it’s time to shape the guitar neck.

In the above picture you can see the neck I’m working on. I first use a band saw and trim the headstock to it’s rough shape and then the neck to it’s rough shape. The neck is narrower at the nut near the head stock and wider near the heel block which is where the neck joins the body. The neck is in my “Shave Pony” which is a smaller, bench mounted “Shave Horse”. The shave pony allows me to clamp one end of the neck and then use various tools to shape and smooth the neck to it’s desired shape and size.

In the picture above, you see some of the tools that I use to shape the neck. There are 2 spoke shaves (black with cherry handles), 2 draw knives (bare blade with wooden handles) and a file. In addition, I use block planes and sanding blocks. The draw knives are for rough wood removal and shaping and the spoke shaves are for smaller wood removal and closer to final size and finish. Various files help in rough locations. Sanding gives it a smooth feel and prepares it for finishing.

I still have a day or two of this small detour before I get back to the binding/purfling that I talked about in yesterday’s post.

A Learning Opportunity

glennth — Tue, 17 May 2011 14:39:44 +0000

I know I haven’t posted in a bit. I have a series of house projects that I’m acting as GC on and it’s taking a lot of time. Hopefully, I’ll get back to working on my guitars by next week. In the meantime…

I’m a member of Shannon Rogers’ Hand Tool School. I was reminded by a blog post over at Giant Cypress regarding this program that we have plenty of learning opportunities via blogs, podcasts (both audio and video). I’m a big believer that learning woodworking techniques of any sort can help you understand more about woodworking and make you a better woodworker. If you like power tools, folks like Marc Spagnuolo’s The Wood Whisperer are a great resource not only for their own content but also the links to others related content. In fact, a video series that Marc posted was the initial motivation for me to try my hand at building guitars. If you like hand tools, then folks like Bob Rozaieski’s Logan Cabinet Shoppe is a fabulous resource. There are more than I’m willing to list out there that fit into power tools, hand tools, are many with a combination of both.

Shannon’s School is an especially useful source. It is a subscription service but is well worth it. He’s produced a ton of content for this first semester and the content is very detailed. If you have ever purchased a DVD from a source to learn something, I’m sure that you have found it useful and worth the money. Well with Shannon’s School, you get more detail than the average woodworking DVD can even think of putting on their DVD. In addition, Shannon supplements the school’s video’s with chances and Q&A to clarify things that may have confused you.

Shannon offers 1 semester at $100 and a full year at $150. I will be a member as long as my budget can support it and Shannon keeps producing great content. I recommend you do the same.

Miter Plane

glennth — Sat, 12 Feb 2011 21:53:27 +0000

I have a shooting board for shooting cross cuts. I still need to make a shooting board for shooting long grain rip cuts.

To this point, I have used either my jointer plane or my jack plane to do the shooting. This has worked find except for the fact that I have to adjust both to cut a finer cut that I generally leave them for their normal work load. I’ve been jonesing for a miter plane to solve this problem.

In addition, a miter plane also is designed specifically for the task of shooting a board so has a proper hand hold. I’ve done a bunch of shooting in one day and the awkward grip on a jointer or jack plane can give the weirdest blisters.

Here is a picture of my Lie-Nielsen miter plane. As you can see the design has a very box shape with exact 90 degree sides to bottom giving a very stable platform for running along the shooting board for precise cuts.

In the picture below you can see the nice grip for holding the miter plane against the edge of the shooting board. I really look forward to my next application of this and my shooting board.

More Bracing Work

glennth — Sun, 09 Jan 2011 05:53:35 +0000

After the X-braces that I talked in the previous post, I needed to work on the other braces and get them glued and clamped.

I’ve reviewed books and videos and have determined (especially for the x-brace) that some other shaping should be done before I glue it up to get even tighter joints. Also, I learned more about specifics with the large lower tone bars and the smaller side tone bars. Next guitar top will benefit from this knowledge. Doing so many guitars in a row really give benefit to each successive guitar.

After this glue dried, I started the shaping. It’s all chisel work which emphasized the forearm muscles which tire quickly. I’ve done almost half the shaping and will try and finish the rest tomorrow. I’ve put my initial effort on the tone bars and the x-braces.

New Year – Back to Work

glennth — Mon, 03 Jan 2011 22:35:40 +0000

After awhile off from all projects to enjoy Christmas time with my family, it’s time to get back to work.

First, I finished glueing up guitar 4′s back on. Now you can see all guitars in progress. On the right, is guitar body 2 which is a cutaway and has some great figure to the maple. The one in the middle is guitar body 3 and is a standard orchestra model guitar. The one on the left is guitar body 4 and is another cutaway.

Now the one issue I’ve had with all these guitars is keeping the center line on the back aligned with the center line on the sides. I believe that the binding will hide all the misallignment issues. On the bottom right, is guitar body 2 where the alignment is off the most and in fact I had to add some ebony to make it less obvious (though it does look cool. The bottom left is guitar body 3 and is just a smidge off while the top center is guitar body 3 is the closest of the 3. I’m clearly getting better but have a while to go where I will nail this element.

The above was easy to show an analyze since all I had to do was take guitar body 4 out of the go-bar deck. The real work was creating the braces for the 3 tops. I’ve used spruce for these braces (which is the same as I’ve used for the backs). I cut a block of spruce into the rough dimensions for each kind of brace and them I shape them using hand planes and sand paper. It’s a messy, messy process making lots of shavings and saw dust (yes, I was wearing my mask). I had to make a lot of them too which made it seem to drag on for quite a while. Anyway, I’m done now and have enough braces for the 3 tops.

Next time, I will start on one of the tops.

Guitar 4 – Alignment looks good

glennth — Sat, 25 Dec 2010 00:25:20 +0000

Today, I took the back with the braces and joined it to the sides. I first had to finish shaping the braces and then create the slots in the kerfing for the braces. All this was exactly the same for guitars 2 and 3.

I spent a great deal of time during glue up getting the alignment of the center lines to match for the sides and back. The problem is that glue allows some slippage and the go-bars in the go-bar deck can cause some pressure that is not directly down when the go-bar is being bent into clamping position. It took a bit and some minor adjustments but I think I got it.

The important piece is that the center strip down the back should be exactly in the center of the edge joining the bottom edges of the sides. In this picture, you can see pretty good alignment.

Keeping Busy on 2 Guitars

glennth — Thu, 23 Dec 2010 22:47:23 +0000

Today, I got to unclamp the body of my 3rd guitar. The joint is very flush and I’m happy with that. I’m disappointed with my ability to align the back to the sides. This is where I’m supposed to take the center line of the back and line it up with the center line on the sides in the mold. On my 2nd guitar, I missed both ends. On the 3rd guitar (the one I just glued), I got the top to line up but not the bottom. It’s especially disappointing since the bottom is probably the most visiible element and really needs to be lined up. I will see if I can find my week technical points for the 4th body. I also cleaned up the glue squeeze out – there wasn’t much so I must be getting better at judging the right amount of glue to apply.

I also worked on the back to the 4th body. This involved more early shaping of the braces and glueing them in place. See previous post for specific steps.

You can see the back for the 4th body on the left and the 3rd body with it’s back attached and cleaned up on the right.

Guitar #3 gets Sides joined to Back

glennth — Thu, 23 Dec 2010 04:37:24 +0000

Today, I worked on attaching the sides and back together.

The first step is to shape the braces on the back. About 550mm from the edge of the guitar, the braces are pared down to about 2-4mm thickness. Once that is done, you determine where to cut the cross braces and the center brace so that you can fit it inside the sides. For the cross braces, there are 2 methods that can work. For Guitar #2, I cut away dado’s for the cross braces in the kerfing and the sides. For this guitar (#3), I cut the dado’s only in the kerfing. The difference is that once the sides and back are glued up, you can see the braces in technique #1 and you should get a smooth fit for technique #2. Once this is done, then you want to ensure the braces are to the edge of the sides (for technique #2) and the center brace goes from heel to heel block.

Once you have a good fit, it’s time to glue up the back to the sides. This MUST be done in the form so that the glueing process doesn’t distort the sides. It is also critical to keep the center lines on the side and form lined up to the center line on the back. This will affect the appearance of the guitar drastically. For the glue up, I’ve again used the go-bar system.

On this guitar, the next process will be to work on the top and get it glued on – closing up the guitar body. I do still have to work on guitar #4 though so that is likely to be my next task.

Sides are done

glennth — Thu, 16 Dec 2010 05:08:38 +0000

The sides are done for both body 3 and body 4 guitars.

You can see body 3 which is the orchestra sized body with no cut away and body 4 which is also an orchestra sized body but with a cutaway.

The kerfing installed nicely and I did have more glue squeeze out (meaning I used too much) so clean up took a bit longer but in the end the sides on both bodies are nice and clean. I still need to do some sanding before I can totally close up the bodies.

As a quick aside, I’ve talked about radiusing the sides so I wanted to show a picture of this process.

You can see on the bench a radius disk. I am using the clamps to hold the disk from spinning or moving. The disk is round but the radius part is where the center of the round disk is hollowed out enough to match a certain radius. Imagine a circle that is perpendicular to the disk with a radius of 15 feet (used for the back of the sides – where the back will attach) or 30 feet (used for the top of the sides – where the top will attach). I got these disks from LMII but you could make them using a router and a jig.

To make the angle of the heel and neck block along with the kerfing attached to the sides match the radius of the appropriate disk, I rough in the size using a spokeshave, hand plane, or chisel until the gaps between the side and the disk are minimal. Then I move the sides (while in the form so I don’t get much distortion) back and forth until I get no gaps. I also have to measure the sides from time to time so that the side on the left is about the same thickness to the equivalent point on the side on the right.

I hope that clears up that process.

No Cut Away Body – Kerfing Glue Up

glennth — Tue, 14 Dec 2010 21:43:05 +0000

I almost wasn’t going to do this post but after how simple it was, I thought I would note a few things. This (body 3) is the first full body (no cut away) that I’ve installed kerfing on. My first guitar was a kit and the kerfing was already installed. A cutaway guitar only has one simple change but it does truly complicate the installation of the kerfing and adds a bit of time to the glue up.

First though, I needed to make the sides to the proper thickness (using a spokeshave) and then sand it in the radius disks for both the front and back. I’m using the same radius’s for this guitar and the body 4 guitar I discussed in my last post – 15′ radius for the back and 30′ radius for the front. When I was doing the sanding, I did notice that this guitar shape seems to have some structural strength that I felt wasn’t in the body 4 (with a cut away) guitar. It will be interesting to evaluate the tonal differences that these shapes impart.

I did take a side jaunt and modified my orchestral model form. I was struggling with doing one side and then the other because the pins used to hold the form together were too long. I shortened them so that most of the time, they will be out of the way.

Glue up was very quick though I suspect that I put to much glue on the kerfing and will have a quite a bit of squeeze out to clean up. Remember this kerfing is the standard kerfing.

Notice that the interior clamps in the form. I’ve never used the top clamp because of the cut away. I did use the trick of pre-bending the kerfing which is another reason that the glue up went so quickly.