Tag archives for edge

Making the Purfling

26 March, 2010
Published by thomas in Uncategorized

I left off last week having started the channels for the purfling. Upon review I was told they weren’t deep enough and so I spent much of this week going over my work. Fractions of a millimeter can make a big difference in violinmaking. Also last week, Mr. Vartanian asked me not to cut the corners. He cut two for me and then wanted me to try and copy his examples. And try I did. Each time I showed him what I thought was a good tracing he would tell me was either two long, short, fat, or pointed to the wrong spot. Mr. Vartanian let me borrow an old book of his with pictures of corners done by Antonio Stradivarius. While mine probably won’t look like those, I did learn that all of his points or “bee-stings” point to 2/3 down the corner edge. Nevertheless, I was allowed to cut the corners on the back and will come back to those on the top.

Mr. Vartanian's Corner

Tracing a Corner

Cutting out a Corner on the Back

To make purfling, very thin pieces of wood are used. The white center is about 0.7mm thick while the black edges are about 0.3mm! I used a block of poplar wood for the white center and Mr. Belote helped me cut two strips about 1mm thick with the band saw. To take it down to the right thickness, a plane is used very sparingly and then a scraper makes the sides smooth.

Poplar for the Purfling

Adjusting the Thickness

Measuring the Thickness

It’s pretty amazing how small of a shaving a plane can take if it is very sharp. I should also point out that wood this thin is very fragile. I knew this ahead of time but by accident, my hand brushed against a piece while it was still clamped to the bench. Even though I barely touched it and it barely moved, I cracked the first pieces I was working on. Since the crack wasn’t too big, I cut off that side and used the rest for the c-bout purfling but a mental note was made on my part.

Wood Split

Mr. Vartanian had some black wood stock stored away that he let me use but I forgot to ask what wood it is exactly. I know it can be ebony but it may be another wood. To help speed things along and just to show me, Mr. Vartanian glued my purfling pieces together. The really cool thing about his process is that because the wood is so thin, as glue is applied it makes the wood malleable and so it can be clamped into various shapes. The clamps of course match the same curves of the violin.

C-Bout Purfling Clamp

Purfling Against Top

All this may seem a little complicated but this process produces shaped wood and can be cut into strips using planes and knives.

Cutting Purfling Strips

Cutting the C-Bout Purfling

This protective and decorative part of the violin now has to be glued into the channel with special attention paid to the corners if I can get the last two just right…

Cutting the Purfling Channel

26 March, 2010
Published by thomas in Uncategorized

Violinmaking is a lot of fun for me but it is also a lot of tedious work. This week (and the next few to follow) covers a process that takes a lot of patience and can really mark the difference between a craftsman and an amateur maker. I’ve moved on to inlaying the purfling which requires very small cuts, chisels and fractions of millimeters to make. Purfling is best described as the black lines that outline the instrument. On most instruments they are inlayed and they act as both decorative and protect against cracks that form on the edge. This week I started cutting the channel to put the purfling into and I ran into a lot of difficulties again working with maple to spruce.

First, let me refresh where I was at the end of last week. The plates were glued together and there were very slight differences in the pattern that I evened out with a file.

Plates Glued to Make Semetrical

Corner Differences

After everything looked even and square, the plates were separated and Mr. Vartanian had me sand down the edge very flat so I could trace the purfling channel.

Flattening the Edge

Flat Edge

I then used a purfling tool which you can find pictured in the Tools section to trace the channel a certain distance in from the squared off edge. Any imperfections in the edge are displayed in the channel and may have to be fixed later on. Also, if the blades aren’t perpendicular or the tool isn’t pressed down enough to make a line, it is very difficult to go back and trace.

Tracing the Purfling Channel

Once the channel was traced, Mr. Belote let me use a sharp knife and a handmade chisel to cut the channel out. The knife is used to cut deeper into the traced line and make it easier to chisel out the wood.

Knife and Chisel Used

Closeup of Chisel

Thomas Cutting the Channel

As I mentioned earlier this is very tedious work. Even with the knife cuts, the wood doesn’t always come out of the grove very cleanly. In order for the purfling to lie nicely, the channel should be about 2.5mm deep and flat on the bottom. I finished the back and found out I was at most 2mm deep in spots and much shallower in most sections.

Channel cut on Back

I am also leaving the corners alone at this point. The purfling tool doesn’t help bring the channel to a point as is standard on most violins. The point where purfling pieces meet is called a bee-sting usually. In great violins this is very clean, follows very smooth lines, and is done all by hand and eye. Mr. Vartanian worked on two corners for me that I will be copying and cleaning. When looking at the craftsmanship of a violin, how much attention a maker puts into the corner and how well it’s done truly says a lot about their skill and probably the craftsmanship on the rest of the instrument. While this isn’t a guarantee it is a good place to start and will be interesting to see how mine end up.

Closeup of Corner

As I started working on the top a lot of problems started happening again. The direction of the grain causes bumps for the knife and even tracing the channel is difficult because the tool can get caught in a straight line and not curve around nicely. The other difficulty is how easy it is to split the grain and cause chips if one is not careful. For as slow as I went, it is not second nature to know how the knife is cutting the grove and a few chips occurred.

Top Grain Chipped Off

Chipped Grain

The first of these and a few others will disappear as I do more work but the second and a corner was glued just in case.

Chip Glued

Channels Cut on Both Plates

So my next task is going back over all the work I did which is what makes this part so frustrating in a way. But I am still having fun and for those of you who never know what those lines were on your instrument, I hope you now appreciate how they got there.

tags: back, channel, edge, front, mistakes, purflingNo Comments »

Cutting the Edge

22 March, 2010
Published by thomas in Uncategorized

I’ve decided to not hurt the corners anymore! You may remember three updates ago I split a corner of the back. Well, working on the top this past week, I cut a corner completely off by accident. I’ve mentioned before how different it is to deal with spruce compared to maple. Since the grain of spruce runs vertically, it is possible to catch that grain and in my case, go straight down it. Of course, it is possible to fix small mistakes like this but this goes to show how difficult it is to produce a violin.

When I worked on the back plate, I used files to bring the edge down where the bandsaw could only rough out. The same process is used for the top but Mr. Vartanian wanted me to be very exact in the corners and smoothly take out small humps with a knife. The pin/pencil line is very easy to see and it makes cutting and filing more exact. As I was cutting one of the corners, the knife caught a rough spot, I was pushing in the wrong direction and the knife made a clean cut.

Cutting the Edge with a Knife

Cutting Corners

Upper Left Corner Cut

Upon showing this to Mr. Vartanian and Mr. Belote they showed me that I was cutting and not slicing the wood. Slicing the wood involves dragging the blade while pulling it forward. I also needed to smooth the wood in the corners more with a file before using the knife. This way there would be fewer ridges that could catch the blade. I let Mr. Vartanian help me fix the corner by using a clamp I was unfamiliar with to glue it back on.

Corner Clamp

Corner Glued Back On

Corner Fixed

Due to the holiday I had less time to work and the corner delay only left me time to continue taking the edge down. When the top was closer (and all the corners nice and intact) I glued it very lightly to the back using only a few drops of hide glue. This is done to make sure both plates are completely symmetrical. Any differences in the edge I will be filing and slicing down before more precisely completing the arching and inlaying the purfling.

Gluing the Plates Together

Closeup of Plates Glued.

Arching the Top

15 March, 2010
Published by thomas in Uncategorized

I mentioned in earlier updates that I would be using templates for the arching. Mr. Vartanian has always used his eyes and he has started showing me angles and ways to look at the arch to make it even and smooth. He also let me borrow a violin he was working on to base my arching.

Arching the Back

I had to pay special attention to the corners to make sure they are smooth and after checking with him one morning he said I was at a good stopping point and I could move on to the top. You can see in the bottom left of the second picture here one of the spots that is going to be thin from the drill press I used flattening the edge.

No Arching Line on the Corner

Leaving the Back

Moving onto the top, Mr. Vartanian cut out my pattern since I’m personally a little nervous about doing something like this on the bandsaw. He is very efficient and cut right up to the line of the pattern. He also said half jokingly half seriously I should keep the extra wood incase I mess up. I put it aside just in case.

Cutting Out the Top

Backup Wood

The Top

Tracing of the Top

I started to compare the thickness of the back to the top just to see how much wood I’m actually going to have to take off. It’s pretty amazing how much extra is needed to create something so thin. I started to use Mr. Belote’s violin cradle to rough the arching of the top and Mr. Vartanian gave me another option for work space similar to his table I used for the back. We nailed two pieces of leather into a bench to brace the plate up against. It was very easy to work with and adjust angles without having the plate clamped down.

Comparing the Thickness

Arching the Top

Leather to Brace the Plate

Leather Nailed Down

Working with spruce is very different from maple. The grain of spruce runs vertically so it has a tendency to split. This is most difficult in the C-bout area. To counter the splitting there, Mr. Vartanian told me to come at the splitting wood from two directions. It is also much easier to cut spruce than maple so I’m finding that I can brace the plate with my hand and work with it against the leather. With a rough 5mm line I started gouging out a rough arch.

Rough Line for Thickness

Wood Splitting

Gouging the C Bout

Rough Arch All Around

Closeup of Rough Gouging

Sometimes wood will have little impurities in it that can’t be seen till it’s cut into. This is common to see in the process of making and sometimes in the final product if it doesn’t get cut away. I found a little one in my top that started to disappear after I cut away more wood.

Impurity in the Top

Since I left the top a little thick when it was being glued together we took it down flat again with a plane taking off about another millimeter. I then went to rough the arching more now using finger planes instead of the gouge to smooth things out.

Flattening the Top

Rough Arch with Finger Planes

Before taking the plate to the drill press, Mr. Vartanian wanted me to take the edge down to 5mm more exactly to help counter messing up and getting too thin an edge at any spots. This I did with a plane as well. Here’s how the thickness is comparing after the edge work.

Thomas Planing the Edge

Roughing the Edge of the Top

Comparing Thickness Front and Back

Before taking the top to the drill press Mr. Vartanian noticed I’ve been working rather slowly and he showed me some ways to more efficiently take wood off. He said it usually takes him about a day to get a nice rough arch for the top. We set up the drill press and I focused more on keeping a constant pressure on the top. I was successful in cutting an even edge this time!

Edge Taken Down with Drillpress

Rough Corner Close Up

Rough Edge

Going back with small planes I took the edge down smooth and left it for the holiday!

Smoother Arching by Mr. Vartanian

Smooth Corner Closeup

Smooth Edge

Arching the Back

12 March, 2010
Published by thomas in Uncategorized

Due to a family emergency this past week, most of my time was spent away from the work bench. The time I did spend, I was able to continue the arching of the back and started bringing down the edge of the arching to the 4.5mm the drill press was set to. This is most difficult to do in the c-bouts because of angles and the grain of the wood running against the direction of the tool. Mr. Vartanian let me use his work space which has a sturdy table that pulls out and he allowed me to clamp the plate to it to work.

The Table

The Table Out

The Plate Clamped

This made the gauge work much easier and I was able to bring the edge down flush with the flat edge already present. Eventually this will allow me to make a channel for the purfling to be inlaid which I’m looking forward to.

Rough Edge

Smooth Edge

Here’s some short news on the top from last week. After the pin tracing was complete Mr. Vartanian’s trick is to trace that line with a pencil. This will create a ledge of lead that will be very easy to see when cutting out the pattern on the band saw. Once both plates are cut I’ll be gluing them lightly together to adjust and make sure they are identical at every angle.

The Top Plate, Traced

I’m sorry for the short update but I promise much more next week. Till then, please send me your questions and comments. I’m looking for a lot of feedback about this site and will gladly entertain anything related to string instruments. I will be happy to answer your questions privately or publicly through the site. Looking forward to hearing from you!

The New Template

9 March, 2010
Published by thomas in Uncategorized

This has been an eventful week. Due to some things that I should have fixed earlier on, I’ve put myself behind a little and had to change my plans some as well. I continued roughing the arching down and found I was more successful going ahead and using a finger plane than the gouge from the previous week.

Back Plate with Finger Plane

Arching on the Back

Back Plate Arching

Now that my edge was thinner I started taking it down again to the pencil line with files and using my original template as a guide. At one point I was checking a few things with Mr. Belote and he went ahead and took the button down at the top of the plate as well.

Filing Down the Shape

End Button

At this point I decided that there were too many imperfections in my template and I had gone a little too narrow in the C-bout that I could no longer use it on the side I was working. An untraditional move, Mr. Belote helped me make a new template. We used a thick paper instead of the poster board and to save time, Mr. Belote cut out the template for me. When cutting out the pattern, you have to do it in one cut because lifting will cause inconsistencies in the pattern which I didn’t want to deal with again.

Tracing the New Template

Cutting the New Template

Cutting the Template View 2

The New Template

The reason I had to cut a new template was to trace it onto the other side. Since my pattern was based on the template from Henry Strobel’s book, I needed something new to make the side symmetrical. I want to take this time to apologize to Henry Strobel. The information in his book is quite helpful and in the right hands can produce an amazing instrument. A few poor decisions on my part led to what I have now and say nothing to the information he provides in his book.

I clamped and traced the pattern on the other side under supervision and started taking down to the line again. Even when the line is mostly gone that isn’t close enough. A fraction of a millimeter can make the entire side look lopsided. It was imperative I get the side down to just the pencil line.

The Pencil Trace

Pencil Line Left

Once I had the pencil line taken away I brought the plate to Mr. Vartanian for inspection. He was approving to say the least, though he could easily tell I had to cut some corners to get to where I was. He told Mr. Belote to help me take down the edge to four and a half millimeters with the drill press using a special circular saw. Mr. Belote took down the bulk of the edge to 5mm as I observed and took pictures. I then took a pass and took it down the rest of the way.

Drill Press Still

Drill Press Moving

Taking Down the Edge

Taking Down the Edge 2

Edge Taken Down

Closeup C Bout

Closeup Edge

Taking Away the Chips

A key to this quick trick is to keep pressure on the plate so that it doesn’t lift up as you slide it under the press. Twice I let up the pressure and the edge is a little thin in those spots. That’s something I’ll just have to live with at this point.

Now that the edge was flat, it made a lot easier to see and measure angles that Mr. Vartanian wanted to check. Most importantly he wanted to adjust the edge of the corners so they pointed a certain way. I started to file these down and then he showed me to take them down with a knife instead. As I took the second corner down the right angle I slipped and heard a crack. I split the wood!

Split Corner

Glued Corner

So, we glued it. In the end, this edge/crack will be rounded off so it’s nothing to worry about; it could have been a lot worse. It’s nice to see instruments made today that look perfect to the naked eye but they too may have had small mistakes like this happen.

A little more time was spent finalize the shape off the new template and other symmetrical measurements and I had to get the new pattern to the top wood. My corners were a little short compared to the template so another untraditional technique/idea was given to me by Mr. Belote. Usually, the template is used to trace the back and the top. Since both of mine are no longer the same as the end product I just clamped and trace the back directly to the top wood. I used a pin to trace the plate which is a trick used by Mr. Vartanian with his template.

Finished Back Shape

Back on Top Wood

Pin Used to Trace Shape

Back Clamped to the Top to Trace

Once the pin imprint is in the wood it can be traced with a pencil making it much easier to cut out and file down. Hopefully this will save me time and catch me up to getting the arching more complete over the next few weeks.

Tag archives for edge

Making the Purfling

Cutting the Purfling Channel

Cutting the Edge

Arching the Top

Arching the Back

The New Template

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