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Hofner Colorama II restoration project part 16 making a new bridge


In the last blog post, we made a new nut for our vintage Hofner Colorama II. Also needing doing is an improved bridge.

The original one should've looked like this:



However, here's the (replacement) one I got on THIS guitar:



Apart from looking wrong (not necessarily a big problem), it has the wrong radius, wrong string spacing, and is not compensated in any way for proper string intonation.

The base is almost correct, dimension- and look-wise, so I'm going to keep it and make a new top.

First I get a brass bar:



Cut it to length to match the base:



Mark the position of the holes and hit them with a punch:



Now the tricky part for me, since I don't have a drill press - drilling the holes perfectly straight:



Holes done:



Now turned over to check how close I got. Not bad.



Quick check with the base before taking this any further:



Sides are now marked with a 9.5 radius gauge to match the neck:



The brass is now filed to shape, checking constantly with the radius gauge to make sure nothing is going horribly wrong.



And here's the bridge after that:



The guitar is then quickly strung up (I've been doing a few things in parallel here, so the guitar finish is done now - I'll do a post about that part soon), in order to determine how to shape the top of the bridge to intonate the strings correctly.

First, I put some little pieces of copper under each string. These are actually little cutoffs of thick copper wiring:



Then I check with a tuner and move the copper wires forwards or backwards until the strings are intonating properly, then mark the position with a pen.



After that, I remove the bridge from the guitar and mark it with a couple of lines that will more or less cut through the six marked positions. There's a certain amount of compromising going on here, but it should still end up giving acceptable results.



After that, I start to shape the bridge using fairly fine files:




Giving us this basic shape:



Then I start finishing it, starting with 400 grit sandpaper and going up to 2000 grit:



Finally I hit it with rubbing compound:



For the sides and back, I put the sandpaper on a flat surface and move the bridge itself. Other than that, it's the same finishing process, from 400 grit to rubbing compound.



And here's how it looks after that:




Finally some slots are added to keep the strings in place:


The aim was to follow a similar style to the bridge that would've come with the guitar originally, while correctly compensating it for an unwound G string (the original would've been shaped for a wound G string). I think it came out OK.

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