Wednesday, October 21, 2015

Rebound?

Not pictured: Shredded Cheese
Somewhere in the back of my head I conveniently forgot exactly how long it takes to scrape binding. I was thinking this would take me 30 minutes - maybe an hour.
Ha!  Two and a half hours later I was left with the pile of shavings in the above picture (and about half that much on the shop floor as well).

So how did we get here?

Remember a few posts ago when I said "Don't slop it on" when referring to applying the binding goop.  Yeah, I should learn to follow my own advice...

"Don't slop it on" you say?
I did the exact opposite of not slopping it on - and had to deal with the consequences of that.  Namely - scraping and scraping and - oh look - more scraping!  Here's how you do it:

Not pictured: Accuracy
First off, this isn't how you hold a card scraper.  You use two hands.  I was taking pictures with one hand and trying to simulate scraping with another - so this isn't really accurate.  Check out the video below to see how this was really done.


The card scraper is a wonderful tool.  You can use it on a push stroke or pull stroke, it is fairly easy to sharpen, and comes in a multitude of sizes and shapes.  One thing some people do is round off the sharp corners on their card scrapers - so that they don't gouge things with those pointy edges.  Some day I will do this - as I did indeed gouge the top a couple of times and had to sand those (rather large) scratches out.

You do this for a while...
I didn't take any pictures of it - but I also used the goose-neck card scraper to get into the curves.  It's the same process - you need to make sure you don't take off too much wood - just binding.  Again, take it slow - if you are seeing more wood shavings than binding shavings you probably want to ease off.

The sides are even easier to work on as you have a built in guide to help you scrape a straight line.  You do need to keep a close eye on how much you are taking off though.  I was a little too aggressive on some parts of the sides and now the binding is a tad too thin in those places.

No, I did not get that scar working on guitars.
I got it while gardening of all things...
Now might also be a good time to talk about consequences.  You see, when you glop on binding paste really thick you run the risk of it not fully curing.  Which is what happened to me.  Even though this had 24 hours to harden - some of the goop was still goopy (or at least gummy) and because of that it wouldn't scrape.  It was like trying to scrape putty - it kind of works - but not really.

My guess is that these didn't harden because the goop was piled on so high the acetone couldn't fully evaporate.  In theory if I leave these now exposed gummy sections to cure overnight they should fully harden.  That's what I'm going to try anyway.  I'll let you know how it goes.  This was mostly a problem at the horn/cut-away.  But there were a few other areas that exhibited this behavior.  Gladly most of the binding was cured and hardened.

Hmmm...
Is that what I think it is?
It is pretty neat to see the finished product appear out of this chaos.  It's kind of like the first time you develop a picture in a darkroom - something beautiful slowly reveals itself.

Once I had finished scraping I did some sanding.
...okay, I did a lot of sanding.

In addition to the scratches on the top created by the edge of the card scraper the basswood strips (the light colored wood in the middle) were damaged by the masking tape.  When I pulled off the tape - strips of basswood came with it.  Anyone who has worked on a spruce top acoustic will know all about this - as it's a common problem.  I've never worked with basswood before - so I wasn't expecting this.  It didn't take a lot of sanding to fix - but just FYI.

After about two hours of scraping and sanding this is how things look:

Oh...

My...

I kind of like that...

Yeah, that will do nicely
Just so we are all on the same page - this is far (far, far, far) from perfect.  As you can see - there's a considerable amount of clean up to do on the horn.  But I need to wait until things are fully cured before I can go after this.

It looks like a wad of gum.
...kind of has the texture of gum too...
What you can't see is that the binding is thinner in some places and thicker in other places.  There are areas that I'll need to drop-fill with more goop and there are places I may just have to accept as imperfect.  I believe they call this having character.

As this is the first time I've bound a guitar in five years and the first time I've used plastic binding in seven years - I'll chalk this one up as a learning experience.


Pictured: A teachable moment

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