Making a double bass

[Roger Hargrave]

I forgot to show you my soundhole circle cutting tools. They were made for me by Brian Hart who is a truely great tool maker. He has made many fantasic tools for myself and others. Right now he is quite ill. I hope that he gets well soon.

 

Cremones soundhole circles were always drilled. From the close up of the lower hole you can see a line where the cutter came from both sides and met in the middle. I have seen similar lines on one or two Cremonese instruments, indicating that the holes were cut from both sides. Also visible on this viola is the lowering of the lower soundhole wing that I mentioned doing to the bass. In case anyone wants to place an order, I have a small side line selling little wooden wheels to model makers.

 

These soundholes were marked from an inside template, which explains the 'free hand' appearance of the lines joining the body to the circles.

[Christopher Jacoby]

Roger, that circle cutting set is gorgeous. Is it commercially produced for sale?

[James M. Jones]

Rodger thanks for the wonderful thread/ it occurred to me while looking at the Basses during VSA that any one making a Bass should at least get a bronze.... what a body of work!  ...

   My question is, would you mind describing the cutters angle? I made one but I think the angle is too steep to be effective. they are a little bit of work to make, and it sure would be nice to have a known target to hit.

[Oded Kishony]

Don't Fostner bits work?

Oded

[fiddlesurgeon]

Roger, wonderful post. Sorry so slow at getting to showing my appreciation

in part because I am slow getting through, trying to put the work into

understanding and picturing the descriptions.

I had the good experience of repairing a broken bass neck once. I can second what

I read on this site once that wooden doweling just doesn't hold up (or at least,

not in my case). On a second attempt, it was my bosses instance on his method

a 3/8" x 5" long lag screw. It must still be holding.

What was a strong reminder of this was the little cap strips on the sides of

the neck root, a very non-violin feature of basses. Luckily I didn't lose or

break them.

Regards,

Steve

[actonern]

Following with huge interest also...

 

And, sitting back, especially, to hear the fat lady sing... the varnishing!

 

E

[Roger Hargrave]

Roger, that circle cutting set is gorgeous. Is it commercially produced for sale?

 

Sorry no, I had them made specially by Brian Hart. 

[Roger Hargrave]

Following with huge interest also...

 

And, sitting back, especially, to hear the fat lady sing... the varnishing!

 

E

 

That is still a few weeks off. The bass is still in Holland, because it would not fit in my car. In about two weeks Rene will bring it in his big van. In the meantime I have to build a drying cabinet that will be big enough. Rene can't transport his and I want to do the varnish at my place because of the time involved.  

[David Burgess]

Roger, that circle cutting set is gorgeous. Is it commercially produced for sale?

One can make a dirty but quite functional version by filing the end of a piece of metal tubing into a  V shape, similar to the shape seen on Roger's cutter. Plug the center of the tubing with a wooden dowel, or fill it with epoxy (I'd probably use epoxy, because it doesn't have grain to make the drill bit wander when drilling the center hole for the guide pin). Drilling that hole is easiest if you have access to a machinist's lathe, of course, and the lathe would also make it easy to fine-tune the ouside diameter of the tubing to the exact dimension you want.

[Adam Edwards]

David I think old golf clubs can to the trick

[David Burgess]

David I think old golf clubs can to the trick

Finally, a good use for golf clubs!

[Oded Kishony]

One can make a dirty but quite functional version by filing the end of a piece of metal tubing into a  V shape, similar to the shape seen on Roger's cutter. Plug the center of the tubing with a wooden dowel, or fill it with epoxy (I'd probably use epoxy, because it doesn't have grain to make the drill bit wander when drilling the center hole for the guide pin). Drilling that hole is easiest if you have access to a machinist's lathe, of course, and the lathe would also make it easy to fine-tune the ouside diameter of the tubing to the exact dimension you want.

Wouldn't Fostner drill bit work?

Oded

[David Burgess]

Wouldn't Fostner drill bit work?

Oded

Or a brad point drill. I was presuming that the goal was to use something more traditional, and which indexed on a small center hole. Without that indexing hole, it might be pretty hard to line the drill up to complete the cut from the opposite side. One nice thing about going from both sides is it reduces the chance of tearing wood out when drilling all the way through.

I just use a normal twist drill myself, drill before the inside is hollowed out, and drill the hole quite undersize because the drill can easily walk sideways from following grains etc. That requires quite a bit of cleanup cutting with a knife, versus drilling a precise hole in the first place.

[Roger Hargrave]

One can make a dirty but quite functional version by filing the end of a piece of metal tubing into a  V shape, similar to the shape seen on Roger's cutter. Plug the center of the tubing with a wooden dowel, or fill it with epoxy (I'd probably use epoxy, because it doesn't have grain to make the drill bit wander when drilling the center hole for the guide pin). Drilling that hole is easiest if you have access to a machinist's lathe, of course, and the lathe would also make it easy to fine-tune the ouside diameter of the tubing to the exact dimension you want.

 

This is more or less what I was doing before I had these cutters made. It works very well. Good shout David!

[Oded Kishony]

There is a type of brad pointed bit that's designed specifically for soft wood. The 'cutters' at the edge are rounded rather than pointed. It should give a very smooth cut. I've seen these drills but I haven't been able to find them for sale. Anyone know where/if they are available?

 

Oded

[Christopher Jacoby]

Neat; thank you! I will foray into tool making.

[Salve Håkedal]

...

Drilling that hole is easiest if you have access to a machinist's lathe, of course

...

 

Drilling a center hole in a cylindrical rod using a bench drill:

Rotate the table left or right so the chuck is outside the table. Clamp a wood beam (say a 2x4 laid flat) on the table reaching out under the chuck.

Put a drill bit the diameter of the rod as deep up into the chuck as possible. Drill a hole in the beam.

Put the drill bit for the center hole into the chuck not deeper than for the chuck to hold it well. Then push the rod into the hole in the beam from the underside.

Drill the centered hole.

[Roger Hargrave]

Oded, to answer your question, either Dick or Gewa had a smaller set in their catalogue. I am not sure if they still sell them, but I am fairly sure it was one of those two companies. This is the smaller set that is also in the box I made for Brian Hart's cutters. (See photo above) Otherwise Morassi in Cremona has a set of four (I think) I have used them as well, albeit some years ago. They do work, but the size is limiting and like the other set I mentioned they are not as well made as the Hart drills. But honestly if you  have access to a metal working lathe they are not difficult to make. However, once you have set the thing up, make a proper set with 0.5 mm steps. I think the Morassi system is probably the easiest to follow and make on a lathe, you just need to make a better job of finishing them. The other thing is keeping the the cutting edges safe. Mine are hardened silver steel (I think). I have never sharpened them although I have already used them for many years. Some sizes I use more than others, but they still feel as sharp as the first time.    

[Jose Catoira]

Not meaning to deviate from the actual subject of this thread, good job on this, Roger.

 

 

 

The set on the back I made myself, from 5.5mm to 10mm in .5mm step, done on the metal lathe takes absolutely no time. THe bits screw onto the handle and the guide shaft goes through them, a joy to use. 

 

The set on the front are from the leftovers of Leonard Labram's workshop, fabulous work as all of you who knew Len would expect, just waiting for the time to get on the lathe and machine up a handle for them. 

 

 

Just a point here, Roger talks of Silver Steel, for the American comrades, that is the British name for Tool Steel... comes annealed and you harden and temper after it has been machined up. 

 

God save The Queen. 

 

 

 

 

 

[Roger Hargrave]

Not meaning to deviate from the actual subject of this thread, good job on this, Roger.

 

drillbits.JPG

 

 

The set on the back I made myself, from 5.5mm to 10mm in .5mm step, done on the metal lathe takes absolutely no time. THe bits screw onto the handle and the guide shaft goes through them, a joy to use. 

 

The set on the front are from the leftovers of Leonard Labram's workshop, fabulous work as all of you who knew Len would expect, just waiting for the time to get on the lathe and machine up a handle for them. 

 

 

Just a point here, Roger talks of Silver Steel, for the American comrades, that is the British name for Tool Steel... comes annealed and you harden and temper after it has been machined up. 

 

God save The Queen. 

 

Jose, thanks for the explanation on the tool steel, I was trying to explain this to an American a couple of weeks ago and did not know the US name.

 

Your cutters look very nice, similar, but much better versions of the set I bought from??? But don't forget to make the handle for Len's as well, they look really interesting with their three blades.

 

Just one question, which queen is it that God should save? The Dutch queen has just abdicated, do you mean her? And why would any of the worlds Queens, (there are a surising number of them), require God to save them. They all seem to be doing quite nicely without his or her help. 

[robertdo]

You know the story about this guy who fell from a cliff just to be saved by a handful of roots that he managed to grab at the last second. He is hanging with the ground 500 hundred feet beneath. He feels he is weakening and won't hold the roots for very long. So he shouts: Please, someone, help!

then a thunderous voices says: I am god. All you have to do is let the roots go. I will stop your fall.

So the guy thinks for a second and in a weaker voice says: Is there someone else please?

[lvlagneto]

Beautiful posts and work.  I am always afraid of working on large instruments.  One tap and pop, and there's a major repair on your hands.  I like my mistakes to look small. 

[CarloBartolini]

Just one question, which queen is it that God should save? The Dutch queen has just abdicated, do you mean her? And why would any of the worlds Queens, (there are a surising number of them), require God to save them. They all seem to be doing quite nicely without his or her help. 

 

Maybe there could be a different meaning for that phrase? God save the Queen, from all the problems she has, I can not even imagine the headaches, may God save her from large amounts of preoccupation. I would abdicate in a flash.

 

Wonderful thread Roger, inspiring even for a non maker.

[Roger Hargrave]

Maybe there could be a different meaning for that phrase? God save the Queen, from all the problems she has, I can not even imagine the headaches, may God save her from large amounts of preoccupation. I would abdicate in a flash.

 

Wonderful thread Roger, inspiring even for a non maker.

 

Come on then, make one. You can also use it as an additional jolly boat, although you might need to varnish it with boat varnish.

 

I am a confirmed republican and much to my families anoyance I always was; at least as far back as I can remember. But I just finished  Paxman's On Royalty, which I can highly recomend. Paxman is also a hardend republican, but his book was almost a defence of constitutional monarchy.  

[Roger Hargrave]

This message is just to say that I am not writing anything more for Maestronet until I have a good explanation as to why my comments on the Boston blog were deleted without any consultation. These comments were not derogatory in any way about Boston, the USA, the victims or their families for whom I expressed deep sympathy. On the contrary I condemned in no uncertain terms those stupid cruel idiots that perpetrated the deed. I suspect that it was my comments about the need for gun control, and about the long long list of shooting incidents in US schools. (See Wikipedia) A list that has many many hundreds of entries. I also pointed out that the US has had a further 2000 shootings since the last school massacre. There families will also remember those incidents for the rest of their lives. 

 

Have the NRA taken over at Maestronet? Or are we only allowed to exchange information without expressing our feelings? I am very sorry to all those people that like to read my comments, but this is censorship that has gone a step too far.