I’m back!! I realize I’ve taken an unplanned 2 month hiatus from posting anything worthwhile, but unless something major comes up I should be back on a regular weekly basis of posting. Between graduating highschool, work, and doing stuff around the house I haven’t had much time for my own projects, let alone posting about them. Anyway…….
I picked up a glass bottle at a yardsale the other day for 50 cents for one purpose: making a glass bottle neck slide for my guitar. A bottle neck slide is a glass tube that slips over your finger and you use it to make the note on the guitar instead of pressing the string like you normally would. Using a slide makes it so you can, well, slide real easy up and down the neck. It also gives a cool, distinct sound to the guitar.
The part of the bottle I used to make the slide was the neck of the bottle (I’m sure you already knew that though based on the name of this post). To make the slide I had to cut the glass at the start of the neck where the bottle tapers and right after the lip of the bottle. To do this I used a glass cutter to first score where I wanted to break the glass at, and then I used heat and ice water to shock the glass along the score lines to crack, and essentially cut, the bottle.
When scoring the bottle, I needed to have the score line go perfectly around the bottle in the same plane so I made a real simple and quick rig to hold the bottle in place for scoring. All the rig consists of is two boards screwed together to make a 90* angle with a wooden dowel attached an inch or so up one of the boards so that the bottle can slip over it. With the dowel stuck into the mouth of the bottle, I could spin the bottle around the dowel while pressing the bottle against a glass scoring tool. This simple rig worked just fine for my needs.
Since this is the very first time for me to cut glass I did a test cut on the bottle right where the bottle began to taper for the bottle neck. After I did this test cut, I began scoring and shocking the glass to make the bottle neck slide. I first scored right at the base of the bottle neck right before it started flaring out bigger. I then poured boiling water over the score line, and then I poured ice water over the score line. This sudden change in temperature shocks the glass and cracks it along the score line. I had to repeat the hot water, then cold water process two or three times to completely ‘cut’ the glass. The break along the score line was surprisingly smooth, but it still needed to be sanded though.
I just used standard 220 grit sandpaper to smooth the glass where it had been cut. I was very surprised that the sandpaper smoothed the glass, but it actually worked quite well. Using the sandpaper I got the edge nice and rounded to where it can’t cut me if I tried.
After one end was cut, it was time to cut the bottle’s lip off the slide. I didn’t have to use my rig this time to hold the glass, I just used the lip as a guide to hold the glass scorer. After it was scored I began the shocking process… I did the hot and cold water like a dozen times and never fully cracked the glass. I had to ramp up the temperature difference to get it to crack. I ended up using a small butane torch/lighter to heat up the glass along the score line and then dunking it into ice water to get the lip off. After the lip was off, I realized why it was so hard to crack. It was because the glass was much thicker there than the previous area. Anyway, since I had to go to the extreme way of cracking it, it didn’t come out as smooth. I had to use some 100 grit emery cloth followed by some 220 grit sandpaper to get it nice and smooth. Also, since I went to the extreme it ended up cracking 3/4″ the slide longways :(. It’s not a problem as I can’t feel it or anything, but it does bother me.
When I was done sanding it all, I tried it out. It worked well except for one thing. As you can see in one of the photos, the sides aren’t perfectly straight. The sides kinda curve in a little which means I have to press down a little on it to stop buzzing. But hey, you can’t beat it for 50 cents!
