This Week in Wood

Sanding a guitar body

glennth — Thu, 05 Jan 2012 23:59:20 +0000

After a bit of time re-establishing the routine with getting kids to school and doing homework with the kids, I got back in the shop. I had left off finishing the install of the binding and purfling on guitar 3′s body. I had done a little clean up and wanted to finish that up.

I use way too much glue. I must be addicted to it because I can’t help myself applying as much as I do even though I know that the squeeze out will be wasteful and messy. The mess makes it really hard to clean up. Sanding it uses a lot of sand paper because the glue dries hard. Scraping is hard on the scrapers and some times, I get extra tear out when a glue bit sticks too hard to the wood. I really need to work on this but for this guitar body, it was too late.

Clean up is a mixture of sanding and scraping. I’m still new to scraping so I tend to over use the sand paper. With bending and purfling, it’s important to keep the sides square and not round over the binding (still perfecting my own technique on this but each guitar gets better). The goal is to have an even thickness of binding around the guitar body and have no round over though we will ease the edges before it’s time to finish (cause, trust me you do not want to play a guitar that the body doesn’t have it’s edges eased – they are sharp).

After the clean up, I do a quick sanding going from 80 grit all the way to 220 grit. I will probably touch up the body again with 220 before I apply the finish.

Above you can see the current state of the guitar bodies. Back left is guitar body 2 which has binding and purfling installed. Back right is guitar body 3 which also has the binding and purfling installed. In front is guitar body 4 which I will begin the binding and purfling installation next time.

This is guitar body 2 with it’s binding and purfling.

This is guitar body 3 with it’s binding and purfling.

Next step will be to pre-bend the binding for guitar body 4 and then on to glue up, clean up and sanding. After that, it’ll be time for the necks.

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Sanding a guitar body

Guitar 3 has been bound!

glennth — Fri, 23 Dec 2011 23:56:41 +0000

Today, I’ll show you a little about how I improved my binding and purfling install.

Below you can see that the first half is finished. Before finishing the 2nd half, you need to square up the ends so that you can get a flush joint. In my case, I usually overextend the glue joint for the first half and have to scrape and chisel out material to get it to be a proper fit. I do my best to line the joint up with the center line of the sound board.

Below you can see that I pre-tape the binding and purfling with a strong focus on the proper order of the pieces, matching the first half so that you get a good look.

It’s important to have all the supplies ready for the glue up. In this case, it means lots of pre-cut tape ready to clamp down the glued up purling and binding. I use an acid brush to apply the glue and dixie cups are always my friend.

I can only show the beginning because after that it’s all about moving along and not letting the glue to set up prematurely. I usually apply enough glue for about 6 inches or so. I apply the glue to the guitar body where I’ve routed the groove and to the purfling pieces and binding. I know that I apply too much but my theory is to allow some to seep into the gaps where possible. It’s really important to push the binding tight which in turn pushes the purfling tight before snugging up the glue.

Carefully work around the body and then get the rubber out and start wrapping and stretching it around the guitar body. The stretch is what gives the extra clamping pressure so make sure you get an ample stretch.

Tomorrow I will get to see how it looks. I will sand the top and back but focus on scraping with the sides due the curves. The back seemed nice and tight so I’m hopeful that we’ll get a good looking application.

It’s a good day!

glennth — Thu, 22 Dec 2011 23:03:18 +0000

Today was a good day!

I decided to try a new approach to the initial glue up.

In the previous glue ups, I run into a problem that the purfling is not pre-bended (it’s just too thin to even try) while the binding is pre-bended. This aggravates the nature of thin pieces of wood getting tangled.

Today, I temporarily taped the purfling down so that it acted closer to being pre-bended. This reduced the tangling effect by at least one order of magnitude and maybe more.

Only one issue is that I got the order wrong in glue up but was already half way through when I figured this out. Fortunately, I can ensure that the other half of the top is the same so it really won’t be a problem and I will probably be the only one who cares or notices. I wanted the pattern for the purfling to be dark wood, blood wood, ebony, then the binding but instead wound up being ebony, blood wood, dark wood and then the binding.

At the bottom of the picture, you can just make out the colors of each piece of purfling. The dark wood is close in color to the ebony so again, it’s probably only me that will notice or care.

I also felt that the tightness of the glue up was great so later this afternoon, when I remove the rubber and tape, I’ll find out.

Less Swearing…

glennth — Thu, 22 Dec 2011 00:40:34 +0000

I got back to my shop yesterday and returned to working on building 3 guitars. The step I’m on (installing purfling and binding) is not fun and actually quite frustrating. Yesterday, I was swearing a lot. In fact my wife, Kathy, came out to check on me.

I’ve broken the job down into 4 installs per guitar. Yesterday was the first for the last 2 guitars and today, I did another. I’m proud to say that no swearing or yelling happened during the install. I’m not saying it went perfectly but instead I remained focus not he task.

The issue, as I mentioned in yesterday’s post, is keeping the 4 pieces of wood in the proper orientation and order. The second issue is ensuring that the install is completely clamped to the guitar body. The first issue can only be solved by more hands and if that’s not possible, slow methodical work. The second issue is something I attack with 2 strategies. The first one is using my hands to clamp and then blue tape to hold it down and work around. The second is to add the rubber and stretch it around the body providing additional pressure on all the key points ( the main one seems to be the waist).

Tomorrow I will continue and by Saturday, this body should be to the point where I start scraping and sanding the binding and purfling to make it look good.

Back To Work

glennth — Wed, 21 Dec 2011 00:03:35 +0000

A few hours ago I got back to my shop.

As many of you might know, my current project (or projects) involve building 3 guitars from scratch. To date, I’ve built 3 bodies which include 2 with cutaways and 1 with full body. I’ve roughed 3 necks out including the headstock.

Right now, I’m working on the purfling (a purely decorative element that works with…) and the binding (provides a hardwood edge to the sound board containing and focusing the sound). I’ve finished 1 body and today began the 2nd body.

The task is very frustrating and is kind of like brading hair but instead of twisting it in an organized fashion, I’m taking 2 very small skinny threads of wood and a slightly larger one and trying to keep them in the proper order while glueing and clamping in place as I work around the body. It’s not as easy or simple as I make it out to be either.

I glued up 1/4th of the 2nd guitar. We’ll see how it turned out after I get the tape and rubber clamps off.

I’ve decided to just get this job done and try to learn from each attempt. I want to get these guitars done so I can move on to the next project (either a desk or a work bench, I’m still pondering).

Motivated or Frustrated

glennth — Sun, 13 Nov 2011 15:47:39 +0000

I haven’t been to my shop in a few weeks. To me (and probably most of us woodworkers), that’s just sad.

The problem, though, may be self inflicted.

Those of you who have read this blog on a regular basis know that I’m working on building 3 acoustic guitars. If you really remember a while back though, I just started building just a single guitar. I had some issues that I thought I couldn’t fix so I started 2 more believing that I learned a lot about building guitars.

I’m currently working on the binding and purfling and have once again had issues. These issues are smaller than that first issue but they are still frustrating and it has caused me to not want to go into my shop. Yes, there have been other factors for not going into my shop from normal life (yard work, helping kids, volunteering, …) but over the course of 2 weeks I can always find time to get to my shop.

I guess some of my frustration comes from jealousy or lack of self confidence. I’m the sort of woodworker that makes lots of mistakes in my learning process. I have been known to jump into something before it is fully thought out so the mistakes can sometimes be large. I do learn and my resulting projects have gotten better and better over the years. Of course, the internet has made other woodworker’s resulting projects and stories in the forefront. It’s hard to not get a little frustrated when i see new hobby luthiers build their second or third guitar and have it turn out like a long time professional luthier.

Two days ago, I forced myself to go out to my shop but I avoided my project to clean and re-organize a few spaces in my small shop.

I need to just get to it and finish the guitars. They will be what they will be. In truth, they will probably sound great. They may have some “quirky” appearance issues (yes, I’m being politically correct so i don’t hurt my own feelings) but that should be ok.

What do you do to work around motivational issues?

In the past, i have started over; given up; found a fix; stayed away and then got back to it; and sometimes combinations of all of these. Starting over and given up are harder to swallow with all the money and time I’ve put into this current project so i don’t think I’ll be going down this path.

OK, this week I’m going to do some work, even if it is small, on my guitars. If I can get the binding and purfling done, it will be on to the neck and fretboard.

School Project for Mitchell

glennth — Sun, 23 Oct 2011 03:40:48 +0000

I’ve been sick and a bit frustrated about my last shop session so I haven’t been in the shop for a bit but today would get me back there.

All week long, my youngest son, Mitchell has been telling me about this project that his teacher said they can do. It’s a “Stoolie”. I told him we couldn’t do it until I had an idea of what it was. Yesterday, he brought home an instruction sheet.

A “Stoolie” is a stool with a single leg. The reason his school is promoting this project is to help kids stop leaning back so much in their chairs during class.

We went to Lowes (which is where the instructions pointed us) to get the parts for this project. The Lowes folks were very helpful and in fact the various department folks said they knew exactly which project we were building. We needed some nuts and bolts from hardware, some pipe and fixtures from plumbing, and a wooden circle from lumber. Mitchell also wanted us to upholster the stoolie so we needed some padding. All went well except for the piping. They were out of the required 1/2″ pipe so we had to go with 1″ pipe instead, meaning an elephant can sit on our stoolie.

We had some cleaning of the pipe to do and then we started on the project. First step, ease the edges of the disk.

Next we found the center of the disk and drilled the holes for the fixture to attach the pipe to the disk.

Next we attached the fixture and tightened the bolts/nuts.

We then worked on the upholstering.

We attached the pipe and tested the height.

Here is the proud builder.

He’s been using it all over the house all day long. It goes to school on Monday.

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.

Guitar Building – Back at it!

glennth — Tue, 11 Oct 2011 20:02:22 +0000

It’s been a while since I worked on my guitars. Now it’s time to get back to it (not that I’ve exhausted all my distractions but really…I need to finish these babies!).

On the right you see my second guitar body. I had already finished the purfling and binding though I don’t consider it a stellar job. I certainly learned a lot from the process. I learned a bit about repairing them though I still have a bunch more learning to get the repairs to look seamless. Of course, i’d rather not need the repairs so I need to learn more about getting the install process to be more flawless. I think the biggest issue was that I did not have the grooves for the purfling and binding parallel to the sides. I used a router and it was a bit angled. I think that I will keep with that method but then focus on more hand tool work to get those grooves parallel to the sides.

On the left, you see my third guitar body. I’ve got the bindings pre-bent (the second guitar body I bought pre-bent bindings). and they turned out well. I will start the groove making and squaring process over the next few days (given my schedule, I’m hoping on Thursday).

I’m looking forward to tackling this luthier business again.

Sharpening – Why oh why?

glennth — Sun, 09 Oct 2011 18:39:00 +0000

As I mentioned in my last post, I decided to refresh my blades throughout my shop. The hand plane blades took me 2 days and then sharpening the chisels took another day. All of that wasn’t really a problem. The real problem is why can’t I get into the rhythm of sharpening when I sense a blade needs sharpening. I even have a dedicated sharpening station.

I have been working on my guitar builds for the last 6-9 months and have often felt that I should be sharpening blades. Why didn’t I get the stones out and sharpening the micro bevel. Each blade might take 3 minutes if that to get a nice sharp edge. It’s not like I have to lap the back of the blades or the soles of the planes. They are flat and even mirror polished.

I think that this routine of sharpening frequently is the secret of keeping sharp blades in a shop.

I know I dread flattening the stones which I’ve always done at the end of a sharpening station but with a single blade, that probably wouldn’t be a problem. Maybe oil stones would be better for the frequent sharpener.

In any case, I will endeavor to get to my sharpening task more frequently.

Sharpening – Hand Planes

glennth — Mon, 03 Oct 2011 01:54:02 +0000

I try to sharpen frequently so that I don’t have a big couple of days getting everything sharp but sometimes it’s just time to clean house. I decided after 2 shop projects and a bunch of guitar building that it was time to do that house cleaning.

First, I started with my hand planes. I have a 3 step process though not all steps are necessary every time.

First step, lapping the sole of the plane and the back of the plane blade. This step is not needed very often and sometimes it’s just an abbreviated step because I’m just cleaning off some surface stain or surface rust (I am in the Pacific Northwest so it’s wet here all the time so rust just happens).

My lapping process includes a flat surface (I use a slap of machinist grade granite) and sandpaper. I start with 60 grit and work up to 1500 or 2000 grit. If I’m just cleaning up a stain or rust, I may just start with 800 or 1000 grit which only takes a few minutes. I fight the stains and rust but using a lot of oil on the bare metal. It works some.

The results of lapping through the 1500 or 2000 grit should give a pretty good mirror finish which is nothing more than a sign that the sole or back is flat and smooth.

You can see the reflection of the paint brushes hanging above my work bench in the back of this nicely lapped hand plane blade.

My second step is to grind the primary bevel on the plane blade. I use a Tormek which has a lot of jigs for a lot of blades. For square blades, there is a square jig and for cambered blades, there is a jig from Jet Tools that works well.

In this shot, you can see the Jet cambering jig. Before I set up the blade in the jig though, I have to determine the camber and I have some templates for that.

I came up with these 6 templates based on my normal hand plane usage and a bunch of research from the internet (wow, there is a lot of info on exactly what the camber or radius should be based on bed angle, desired shaving thickness and blade width). In the case of the smoothing planes that I showed in the first picture, I use a 120″ or 150″ radius camber which is nearly flat but just a little tapered at the edges.

Kathy happened to come in at the grinding step and took a couple of action shots.

The final step of the 3 step process is one I do anytime that I’m sharpening and that is refreshing (or if I have grinded, creating) the micro bevel. For a square blade it is an easy task. The grinding gives the primary bevel a hallow which allows you to get a well defined flat. Once you determine this flat, you lift off of that flat so that you can sharpen the smallest micro bevel. I target 1/32″ or there a bouts for mine. For a cambered blade, you need to do the same but then rock as you pull the blade across the stone from one corner to the other. I use a magnifying lens to check my progress OFTEN.

I use Norton water stones. I’m happy with them though I may try Shaptons when these are exhausted.

When all this is done (or the steps that I need to do), I then reassemble the hand plane and test it out. I spray oil on the hand planes after each use again to fight staining and rust. As of this writing, I’ve got a nice arsenal of well tuned hand planes.

P.S. I’m still struggling with specialty blades (skews, funny shaped rabbit blades, and such). As of this point, I don’t grind these blades but just use the water stones. It’s a little more hand work but the set up on the grinder would probably take a bunch of time too.

Next I am moving to sharpening some chisels. After that, I always offer Kathy to sharpen some knives and she sometimes volunteers me to sharpen her mom’s knives too. In another day or two, we will have only sharp tools in our house.

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.

Introducing – my Wall Hanging Tool Chest

glennth — Mon, 26 Sep 2011 14:18:28 +0000

I did some sanding and hardware installation. Getting the doors hung square and even with one another took quite a few re-do’s. I probably spent more than an hour on it to get the door hang just right. I also put on nice wood knobs and some magnetic catches.

I’m super pleased with the way it turned out. It makes my shop feel a bit more finished and professional (though I will continue to be a hobbyist).

I was going to go with piano hinges but I decided that they would be overkill so I with a smaller hinge.

I still see plenty of mistakes and even one big one that I’ll notice every time I walk into my shop but I’m still immensely pleased with the results and what I learned in putting it together.

Doors almost done

glennth — Sun, 25 Sep 2011 21:45:10 +0000

Yesterday was a good day. I got to make lots of shavings. I always tell my wife when I’ve had a good day that “I got to cut wood”. Of course it sounds a bit juvenile but the fun I’m having doing woodworking lately is very kid like so I’m ok with that.

I started by making rabbits in the panels so they would fit into the grooves for the rails and stiles. The groove was 3/8″ and I wanted a snug but free sliding fit. Some edges I got that exactly but others were a bit looser. I sometimes get too excited in making shavings and forget to check the fit. When I was learning how to solder electrical items, I always had the same issue because I thought it was amazing to melt solder and so I would have big gobs of solder on my joints. I’ve gotten better at soldering so I hope I can get better at fitting.

The results at least looked nice.

I spent so much time the day before ensuring very square panels that the dry fit was hardly any effort at all.

With my skewed rabbit plane, I have a bit of a problem once in a while where the depth stop or the fence slide from it’s position. I know exactly why. I’m too strong for my own good and apply too much pressure and force the fence/stop to slide. This happened on the back of the first door. It’s not visible and I fixed the plane and my technique for the second door.

Now we are in the home stretch. Next step is to begin attaching the doors to the cabinet.

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!