Violin Bass Build

[BPM Strings]

333C825D-4A07-483E-930E-C2197ADD500E

• BPM Strings
• Jan 18, 2019
• 500/1 höfner violin bass

The wood and half template

Hello everybody, my name is Benjamin McPherron. I am a professional violin maker and bassist. I recently started to build Hofner 500/1 copy as I have always loved how they sound and this model will allow me to use my violin making skills. I thought it would be fun to share this build on talkbass, I will be using some techniques and methods you might not often find here.

The primary woods on this bass will be curly maple for the back and sides, all made from one block, Alaskan yellow cedar for the top, maple for the neck and a rosewood fretboard.

 

[Jon Clegg]

Cool. I'll enjoy watching this. Always enjoy learning new things!

 

[83_Silberpfeil]

Looking forward to it!

 

[BPM Strings]

Most of the hardware for this build has been ordered and is en route, but I thought I would post a pic of the pickups. Hofner “toaster” single coils for that vintage vibe and because they are sexy as hell.

C9DCB261-D039-47EC-9EA1-B2EF40D4C4B7

• BPM Strings
• Jan 18, 2019
• 500/1 höfner violin bass

The mold and blocks

96033E74-3A5E-4875-9142-BE3A69E76AB9

• BPM Strings
• Jan 18, 2019
• 500/1 höfner violin bass

Blocks being glued into the mold

Here are a couple shots of the inner mold and blocks and the blocks being glued in. The mold is made from 3/4” plywood, the neck block is mahogany, the end block is spruce,and the corner blocks are cedar. For those who are unfamiliar with how an inner mold works, you attach the blocks, then you shape them and glue the ribs to the blocks. When you are ready you detach the blocks from the mold and shape the inner surface of the blocks and then you can glue the top and back on. This is the most simple version of an inner mold, for instruments I plan to make several of I make a 3 piece mold that is the full thickness of the ribs, and I can then take the outer layers off to get the linings in.

 

[BPM Strings]

Flattening and straightening some maple to make ribs.

Then resawing a rib off the block. Rinse and repeat until I have enough rib stock plus one extra to mess up.

Then the rib stock is run through my home made thickness sander to a hair over 2mm thickness.

And finally the rib stock is scraped smooth which takes it to around 1.9mm

 

[BPM Strings]

Here’s the blocks glued to the mold and the outline drawn on the blocks. The corner blocks on the left have been cut to shape on the c bout side only.

The first c bout rib has been glued and the second is being glued.

Then I cut the outer side of the corner blocks and the rib as one. Next I will cut the neck and tail blocks and fit the rest of the ribs.

 

[BPM Strings]

Here’s a rib for an upper bout about to get bent.

After bending I clamp the ribs to the mold over night to make sure they are dry after steam bending them. Then they get glued to the blocks with hot hide glue. And so on and so forth until all of the ribs are glued on. Meanwhile...

Strips are glued to the top so that I can lay it face down on my bench without it rocking.

Then I have to plane the strips down to be level with the “peak” on the middle of the top.

Finally I can turn the top over to flatten and smooth the underside.

The back gets the same treatment, but being milled from a slab it doesn’t need the strips glued to the outside.

 

[ctmullins]

Very nice! So different from the usual hack jobs that I do...

 

[BPM Strings]

All of the ribs are now glued on.

Now that I have a completed rib garland I can trace the outline. I used a washer to make the line about 3mm outside of the ribs. On violins, I use a bigger washer at this stage and after the arching is roughed out I take the edge down to the exact overhang by hand. This instrument will have flush edges with binding, although I did consider doing an overhang with purfling. The overhang at this point just gives me something to beat up while I carve the arching, a margin of safety if you will.

I cut to the line with my bandsaw, then I then use a slot cutting bit in my super crappy router table to establish a preliminary edge thickness. My final edge thickness will be 4.5mm, but once again I leave it thick at this stage for a margin of safety. I set the height under the bit to a hair under 7mm, and what it cut varied from 6.8mm to 6mm. Such a crappy router table. I don’t cut very deep here, it’s just to mark a thickness. If I trusted my setup I might cut to just over the edge thickness, but I don’t so I won’t.

 

[BPM Strings]

To get the arching started, I get out the angle grinder with a Lancelot chainsaw bit. It’s quite a mess, definitely an outdoor job.

Now that most of the waste has been reduced to shavings by the grinder, I can begin to refine the arching. First, I plane it down to close to the final arch height, in this case it’s 17mm. I then take the arching templates I made from the plans I’m working from, (I’m using plans from JAGuitars if I haven’t mentioned that) and I establish the lengthwise arch first.

Next I use the templates to get the side to side arching close to where it should be. At this point the edges are still thick, and the arch height is a little to high, but the overall shape is close to what it will be in the end. I’ve decided to follow the plans for the top arch even though it seems to me to be a shape that would work well in whatever press they use to shape plywood in factories, but maybe not the most beautiful shape. The reason is that Hofner figured out how to make it so that the pickups will fit under the strings with a good neck angle and a reasonable bridge height, and I thought it best not to reinvent the wheel. Those concerns don’t apply to the back however (the plans show the back and top having the same arch), so I’m thinking about throwing the templates out the window and doing what I like for the back.

 

[SomeGuyIThink]

No post of final version?