Dave Hynds Site

[Jim Garber]

I recently won an auction for a repro bridge on eBay and just realized that Dave Hynds, the seller, has posted here. He has a nice Web site dealing with his work. He had posted here some time ago asking about the fittings (bridge and tensioner) for a Demeglio clone he was restoring.

I like his page on bridge fitting. Detailed and with photos.

Jim

[onthefiddle]

A nice clear web page, but I'm afraid I still maintain that sanding bridges to fit doesn't really work. To get optimal contact between the bridge and the front requires the bridge to be fitted to it's exact position using edge tools.

Of course if you are not damaging the instrument in any way by doing this (it depends on how heavy handed you are, but should be fine with care) then there is no objection in terms of maintaining the health of the instrument, only in respect of getting the best acoustic response from the instrument. As such it is a very amateurish technique (fine if you're an amateur ).

I see that he offers "refinishing" (over woodfiller)

Jon

[Martin Jonas]

Jon --

I recall that Frank Ford's article on the topic at frets.com (which is down at the moment, so I can't double-check) has a mention that many violin builders/repairers don't sand their bridge feet because they consider that sanding damages the fibre and thereby creates an inferior acoustic coupling. Is this the reason why you wouldn't do it that way, or is it because the sanding track necessarily means that you will end up with a bridge curvature that is averaged over a greater area of the top than the actual bridge footprint? As far as I can make out, the fibre damage point of view is not widely accepted in the mandolin field.

Frank Ford recommends sanding only as a means to highlight the contact areas, which he then shaves down with an edge tool until the entire bridge foot makes contact.

Martin

[onthefiddle]

I have never heard of the "fibre damage" argument Martin. It sounds like some kind of Guitar maker's joke about Violin makers to me

My objection is that you cannot achieve an accurate fit between the bridge and the soundboard by sanding. On a bowlback I would imagine that you would also have to be very careful not to damage the soundboard at the cant.

I can see the validity of using it to show up contact points, but it would do so less clearly and less accurately than chalk, which can work very well as an aid in fitting Mandolin bridges.

There was a thread regarding this issue in the Builders/Repair section a while ago here.

Jon

[dave17120]

Hi, still building my site.... any helpful suugestions gratefully accepted.
Bridge feet.... tried with chisels, lost too many bridges trying to get it just right... ended up too low. PLUS if I'mm offering 'non-experts' bridges to fit, I felt I wanted to offer some support for fitting that could be managed.
AND... Jon, 'over woodfiller'.... was that a question?
When I refinish I usually scrape down, then progressively sand to smooth, before refinishing. What woodfiller?
Interesting to have found this section, have really only used repair section so far. All the best, Dave

[onthefiddle]

Hi Dave,

Regarding the bridge fitting, it takes practice, but given time you'll find it at least as fast, the fit will be much better - and so the transmission of vibrations from the strings to the soundboard more efficient.

Refinishing isn't a professionally accepted technique. If you were to take a refinished instrument to a shop they would halve it's potential value, even if it was beautifully refinished. A poorly refinished instrument is further devalued by the cost of finishing it once again.
The professionally accepted method of dealing with varnish problems is retouching. If this is well done it will not depreciate the value of the instrument at all, and should certainly enhance an instrument's beauty - without changing it's character. Once again, retouching takes longer to learn , but the results are definitely worth it.

I recently started a discussion of the ethics of repair and restoration here.

I will try to link to an image from your site. Assuming that it works - isn't this filler you have used here?

Jon

[dave17120]

Ah yes, that one, I learnt a lot from doing that one!? An early repair where unfortunately the effect was not what I hoped it would be.
With regard to touching up varnish, how do you deal with large areas of damage. I'm particularly thinking of some of the German ones I get that are presumably sprayed with some kind of lacquer, and often devastatingly damaged. I have no spray equipment, and frankly, from the toxic nature of the stuff, no real wish to get any. The Italian ones are mostly French polished, so I try to work round that.... I'll learn how to one day. Dave

[onthefiddle]

Laquers require a slightly different approach from varnishes (either oil or spirit), but spray equipment is definitely not necessary (my retouching brushes range in size from 1 to 00000 - so pretty tiny). I assume that what you're describing as large areas are areas with an accumulation of damage, from the plectrum for instance. Try to think of this as a lot of small(ish) scratches rather than an area of large damage, and deal with it scratch by scratch. Also I would advise against going to fast - build up many layers to achieve perfection, rather than swamping an area.

The materials to use for repairing a laquer finish vary according to the laquer used. I wouldn't be able to identify a laquer from a photo, so your best option is to take the Mandolin to someone experienced near you. A good luthier used to working on guitars should be able to help you, particularly if they have trained in the fine French tradition which is still perpetuated at Mirecourt (or at any of the professionally oriented courses of study in centres of making and restoration elsewhere).

If you are interested in studying there are part-time courses available in France, as well as the full three year course which is taught at Mirecourt. For instance Le Bois de Lutherie offer courses, as well as offering fine tonewoods.

Jon

[dave17120]

Thanks for that, I am learning all the time I hope. Finishes is one huge area I am gradually getting into. Are there any circumstances where you might 'refinish' an instrument completely? Dave???

[onthefiddle]

Hi Dave,

The only circumstance in which I might completely refinish an instrument is if someone else has completely refinished it very badly.
Of course, as refinishing halves the value of an instrument, this would only occur when an instrument was quite valuable before it had been refinished. Thankfully I have never come across an example this bad.

I have rescued quite a number of of poor refinishes though, and had to leave many many more - as the much reduced values of the instruments would not justify that much work. Normally these instruments have suffered in a number of other ways also, and their value is such that it is hard to justify much more than setup work, assuming that they are stable enough to play.

Jon