Mandocello Demo

I know that quite a few of you have been wondering what Jonathan's 10-string mandocello sounded like. Well, with many thanks to Jonathan, here he is with ‘cello.  The video was recorded on an iPad and the tune is "Hare's Maggot" (trad.) from Playford's English Dancing Master of 1651. The 'cello seems ideally suited to the tune and Jonathan's playing.

You’ll also note that there is one of the pin-point capos at the second fret on the bottom course, giving an open D.

10 String Mandocello

Jonathan’s 10 string mandocello has now been completed and he came up at the weekend to collect it. After the mandocello’s long gestation period and the to-ing and fro-ing of so many emails, it was good to meet Jonathan in person again (I built him a guitar 5 years ago). As I’ve said before, it’s always a great compliment to be commissioned for a second instrument.

Anyway, below are a number of photos of the completed instrument. I’ve include a photo of the ‘cello with me, just to get an idea of scale! And before you ask where the video is, I felt that I was unable to do the ‘cello justice, but Jonathan has promised one, once he has got to grips with it; as you’ll see, it’s a magnificent beast!

Pin Point Capos?

In a previous post about the mandocello, I mentioned pin point capos. This is a custom feature that Jonathan specified; the idea being that individual “capos” can be screwed directly into the fretboard, stopping the pairs of strings at the required fret to allow for a variety of open tunings.

It appears that there are very few instruments around with these devices, so as far as I 'm concerned there is no right, wrong or should I say established way!

So, from first principles…..

The fretboard has to have a threaded hole, in order to take the screws, but even ebony would not be resilient enough, so a nut has to be inserted into the ‘board. In order to get the nut in the correct position, it can only be fitted once the mandocello has been set-up.

The nut also needs to be as large as possible, so that there is the maximum possible depth to the thread. This, however, is governed by the space between the strings- it so happens that on this instrument, a M2.5 screw fits with minimal disturbance to the alignment of the strings.

So after a trial............

...................... the fretboard had to be drilled, a nut inserted and then filled over. 

After looking at many different types of fixings, I decided to use button head socket screws. They do not have any sharp edges and sit quite low, so they should have minimal interference with Jonathan's playing and as importantly not inflict any injury, if accidentally caught by a stray finger! They’re also made from stainless steel (as are the nuts) so that they will not corrode in contact with sweaty fingers.

The next choice was for the material which comes into contact with the strings and presses them down on to the frets; essentially large, soft washers. Either felt or rubber seemed to be appropriate choices but after testing, the rubber was far superior, the felt just fell apart.

Also I had to perfect a method of making the washers. I made up a mild steel punch which worked very well on thin rubber.

However, it soon became clear that a thicker rubber washer was required, so again a bit more testing.

3mm thickness worked the best but using the punch distorted the rubber, so I improvised this “press” and then made a simple jig to drill a hole in the washer’s centre. Rubber, being flexible, isn’t easy to work accurately and to get 10 good ones, I made 27!

And at last a pin point capo!

One other advantage of the rubber is that, once the capo is tightened down (so that the string is firmly pressed onto the fret) you can still tune the strings and you may need to, because if you overtighten the capo, the pitch of the string will sharpen.Now of course it took many hours to get to this stage, not only experimenting in the workshop, but also on the internet trying to source components, buying them and later rejecting them!

The next question is where do you keep those tiny capos when not in use?

Both Jonathan and I wanted them kept on the instrument and the most unobtrusive position, I feel, is the back of the head. So I designed and made this Swiss army knife inspired gismo.

 The Allen key slips into a slot and is held in place by two tiny rare earth magnets and there are embedded nuts to take the capos. Being fixed between the tuners, also helps to protect the capos from accidently getting knocked.

And there we are; you would not believe how long all that took! Now I'm ready to strip down the 'cello and start polishing.

Mando… la & cello

Like many luthiers, I cut my fret slots using a special type of mitre box with various scale length templates.  

Here's my modified StewMac jig.

The fret slot templates are commercially available and are machined extremely accurately out of stainless steel, to ensure that the instrument is in tune with itself.  The trouble with this kind of jig is that you can be limited to your choice of scale length by the templates that are available.

For Peter’s mandola, I wanted to use a 410mm scale length which needless say isn’t available “over the counter.” So I was very pleased when I came across Carlos at  GW inPortugal who makes templates to fit the StewMac jig and was willing to custom make one for me at, I might add,  a reasonable price!

And here’s the mandocello; it’s just been set-up and I’m now working on some pin-point capos….more on those later!

Mandocello and more..........

Here are a couple of photos of the mandocello, now that it has been fretted and had a good clean-up.

You might think that this one is taking a long time to build…..and you’d be right! Although most aspects of the instrument had been designed before the build started, you simply can’t figure out everything until you see certain parts constructed and in front of you and that is why it’s a slow process building a one-off.

The next step is to make the tailpiece and although I’ve made quite a number them, this one, being a heavy duty ten-string version, needs some designing too.

You’ll notice that there are two ‘pieces being made, the second is for Peter’s mandola. Peter purchased Standard V from me in 2013 and he’s now commissioned a matching mandola. Always grateful when a past customer comes back for more!

Here are a few photos of the body now that it’s been bound.

Also I’ve been working on the design of a guitar for Roland, which is going to be a really interesting project. More on this one later!

Roland has also commissioned a mandolin, so at the moment I’m just preparing various components.

Looks interesting eh?

Mandocello coming together.....

Below is a sequence of photos to show the neck and fretboard going on to the mandocello. There were a few stages to go through; the dovetail fitting, then two pieces of rosewood which make up the fretboard support (with a touch of old school Gibson A influence), routing two slots so that the carbon fibre inserts run from under the nut down to the 20^th fret.

Last but not least the fretboard itself.

Binding the mandocello

I’ve just completed the bindings and purflings for Jonathan’s mandocello. The first thing you have to do is cut a rebate around the edges to take the strips of purfling and binding. Normally, it’s relatively straight forward, as you can sit a router on the body of the instrument itself. However, with a carved/arch top you have to be a bit more inventive! I fixed the router’s motor into a pillar drill stand, and then clamped the body back into its external mould- this allowed me to adjust the position of the body in space, so that the glued edge between the top and the sides was level.

With the router set to the correct height, the body could then be feed into the cutter and the rebate cut. However, it's always a good idea to go around the top with a good old-fashioned purfling cutter first- this helps to eliminate the grain tearing.

It proved to be remarkably stress-free, and got me thinking about the “True Channel” type router jigs sold by StewMac and others. Now I could spend a few hundred quid and buy one, but that would be too easy……………..watch this space!