Brass Horn Repair With Ice
Intro: Brass Horn Repair With Ice
Use the power of ice to remove dents in a horn. If you live in a cold climate, you know frozen pipes bursts. That is because water expands about 9% when it freezes. You can use that property to pop out dents and expand crushed tubing in brass instruments with a little luck. I had a crushed leadpipe on my old horn that I couldn't reach with a pushrod (out of a V8 motor, worked like a charm with its rounded end!) So I filled the leadpipe with water, sealed both ends at the mouthpiece receiver and first slide with a rubber balloon (or fingers cut out of a latex glove) and pipe clamps loosely tightened. Put horn into freezer for 4-5 hours or until your sure the ice is solid. Take out with a towel and set bell down so it will drain out. You will notice that the ice has expanded out of the leadpipe. The amount of expansion out of the leadpipe is proportional to the amount of outward force it exerted, ie, if no ice came out, your leadpipe will probably have burst, or at best straightened out completely! Remove seals and let water drain. With any luck, your dents or crush zone will have been pushed out by the expanding ice. If it didnt work, you can try sealing the ends with a more rigid device like a cork or hard plastic cap. Be advised that if the water has nowhere to expand, it may rupture your leadpipe or brass tubing, so keep that in mind. Hope it works, you really have nothing to lose and your horn will be cleaner than when you started.
38 Comments
Foxchase 6 months ago
DennisK107 5 years ago
swander 5 years ago
DennisK107 5 years ago
swander 5 years ago
Be positive and constructive.
swander 5 years ago
Child_of_Eru 5 years ago
Bassoonist9 6 years ago
Bands-are-life 8 years ago
TooSlowTube. 8 years ago
This seemed like a really good idea, but I can now confirm that it can go badly wrong.
I tried this today, to attempt to remove a dent from my Eb tuning slide - my single French horn came with an F tuning slide, and an Eb one, which is the one I like to use. It fell off while I was emptying water out, a few days ago, and made a dent.
I did this with fingers cut off an old thin silicone rubber glove, and rubber bands. I more or less filled the slide with water, and put it in the freezer.
The slide split in two places. The dent wasn't removed or even noticeably improved.
Since I didn't want to be without it, I've patched it with blobs of lead free solder, and a blow torch. Really, it needs mending properly, which means I'll probably be deprived of it for some time - that's what normally happens when I take an instrument to be repaired or serviced, which is why I rarely do.
It was actually playing just fine with the dent. It would have been far better to just leave it.
swander 8 years ago
TooSlowTube. 8 years ago
It's probably a factor, yes. The problem is, in a curved tube, there's often going to be nowhere for the ice to expand to as the water freezes. Obviously, that's what you're exploiting to try to push out a dent, but if it expands too much, it will split the slide. In my case it split it in two places, but left the dent alone.
The ends and outside surfaces of the water will freeze first. The frozen ends form plugs, which won't move easily, especially when the slide has taken a knock making the cross section vary.
The outside edge of the curve on a slide can be very thin, where it's been stretched to make the shape, so that will sometimes be the easiest route for the ice to escape.
I see Dawkes (UK shop) sell a selection of different sized metal balls with holes through them, for taking out dents. I guess you string them on a wire or strong fishing line and pull them through. That's probably a lot safer.
swander 8 years ago
yes, the balls. You use them to broach the dent out. problem is the curve may be tapered so the balls are a multi size operation. To get the ball around a curve you use a small cable and a slide hammer to pull the ball through the dent. That is production work as the precision ball collection is expensive and is beyond the DIY approach. Suitable for an expensive instrument repair.
TooSlowTube. 8 years ago
Those balls are certainly not cheap. Given my record on taking instruments to be repaired, and not getting them back for a couple of months, I'm inclined to DIY a little more than most people might.
I'd consider buying a few balls around the right size and trying it. I don't want to split the crappy soldering I did to patch it up though, so I'll just leave it, for now.
Fostegert 9 years ago
swander 9 years ago
Fostegert 9 years ago
swander 9 years ago
enough to fill to first bend or wherever you can cap it, first valve?
JoshuaF2 9 years ago
There's a kink in my leadpipe and was wondering how much water is safe to use for something like this?
GofishRC007 12 years ago