Thursday, July 16, 2009

Waiting for Parts and Prep to Practice Finishing

Wednesday, July 15, 2009

While it was drying and then after I took the clamps off, it was pretty apparent from the visible gap between the fretboard and neck that I either applied too much hide-glue or that one or both surfaces were not as flat as they should have been. My guess is probably both.


As you can see, the gap on the bass side is significantly more visible than on the treble side. So I faced a choice - leave it and try to fill the gaps or take the fretboard off and try to level and reglue.

I opted for the former.

At this stage, I think I have made more mistakes and bad decisions than not - so I’m OK with filling the gaps and seeing what I can do to make it look good. I am comfortable that this is not one of those items that will make a noticeable difference in the sound or playability, so it should be just fine.

Since I am still waiting for my parts to arrive so I am having to find other little things to work on until the rest of my binding and stain get here. A couple of the things I found I had to do are shaping the nut, trimming the fretboard extension “ears”, and preparing to seal the soundboard for staining.

I have been reading up on different methods for cutting the grooves in the nut for the strings and most of them are kind of expensive. For example, you can spend anywhere from $50 to $100+ for a set of nut files from Stew-Mac or LMI or you can buy similar items on eBay in about the same price range. Another route I read about, though, is a reasonably inexpensive, home-made one that ought to work really well - create some miniature “saws” using feeler gauges. Here is how this works (in theory); each string size has a specific diameter range - in my case the strings will be .011, .014, .025, and .041 inches in diameter. Because the slots in the nut needs to be just a little bit bigger than the string in order to prevent binding, the slots will ideally be cut to just a little bit larger - in my case I am going to target .013, .016, .027, .043. By taking a set of feeler gauges and sawing shallow slots in one edge, with either my bandsaw or a cutting wheel on my Dremel, I can make a range of “saws” that can then be used to cut slots to the appropriate sizes.

So earlier this week, I went to my local auto parts store and bought a set of feeler gauges for right at $6.00.


As you can see, the gauge sizes do not fall exactly on the slot sizes I am looking for, but I read that it is a pretty easy task to wallow a narrow blade enough to get the size slot you need. Of course, one could always using two blades together, too? We’ll see.

Now that the fretboard is glued down and dry I am able trim the extension “ears” down to give the fretboard a more graceful visual transition to the soundboard.

I couldn’t see any easier way to do this than to use my carving tools and then sand them smooth, so that is what I did. Aside from some minor grain issues that made carving a bit tricky, this went pretty smoothly. Here are the finished results.


As you will undoubtedly notice, there is still a fair amount of finish work I need to do to the soundboard scroll, but you can an idea how filling the gaps in the bass side of the fretboard is going to work - obviously a bit more sanding and scraping to do, but I think its looking pretty good.

And finally, I will soon be looking to stain and finish this old girl. But before I do, I thought it a wise idea to try out some of the techniques I have been reading about on my previously ruined soundboards.

Here is the soundboard before sealing it. All that has been done to it (except ruining it, of course) was to sand it down with 320 grit paper.

To begin with, I thought I would try sealing the wood using a slightly diluted mixture of hide-glue.

From what I have read, a lot of people have trouble getting their stains to come out uniform when staining raw wood, especially on the end-grain of spruce soundboards. Consequently, a common practice is to seal the wood first, sand it down really well after it dries, and then apply your stain. As you can imagine, there are many different opinions and options for this, each with its pros and cons, one of which is the hide-glue method. Since I already have it and hide-glue is an accepted sealer by many luthiers, I thought it sounded like a good one for me.

I didn’t find anybody saying exactly what formula they used to mix their glue, only that it needed to be thin enough to brush on, so I went with about a 1 part glue to 3 parts water ratio (by weight) and then heated it up to about 135 degrees F before brushing it on.

If you look closely, you can see in this photo where I have just started brushing the hide-glue on.

And here is what it looks like after 24 hours of drying, but no sanding yet. I will let it cure for another 24 hours before I begin to stand.

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