Chrome Plating from Planet Nebtar

[Crazy4Tbone86]

A little background first.... I am building a custom Bach 42 slide for a college student. The student specifically requested that the slide be 7/16 of an inch longer than a standard Bach slide because he wants to pull out his tuning slide less. He also wants a longer slide to make low C (trigger + flat 7th) more playable. I advised him that the horn could be nose-heavy, but he still wants to go forward with the project.

I ordered new inner and outer tubes from MK Drawing and asked MK to NOT trim any of the tubes, so they arrived extra long.....even the inner slide stockings were much longer than normal. The longer tubes allow me to custom cut everything and fabricate a longer slide.

While cutting the inner slides, I encountered THE HARDEST chrome plating that I have ever worded with. First of all, when I started cutting the inner tubes to length, I went through 8 or 9 jeweler saw blades. Normally, it only takes 1 or 2 of these fine-toothed blades to cut both inner slides.

Then the real challenge began.....removing the chrome plating to create a solder area under the brace flange/cork barrel areas (you cannot solder chrome plating). Normally, I can spin the tubes on my lathe and remove the plating with a file and emery cloth in about 8 -10 minutes. Insider information.....it's not a good idea to use a lathe cutting tool for this process because the chrome plating can grip the tool and destroy the inner slide (I witnessed this happen many years ago). Anyway, these darn slides took me 75 minutes of filing and sanding each!

I don't know who provides the chrome plating for MK these days, but I am telling you....that chrome is other-worldly! It must be from the planet Nebtar. This kid is going to get a slide with inner tubes that are going to last for 400-500 years! Kudos to MK Drawing for finding a chrome plating company that plates with such a tough metal!

http://trombonechat.com/download/file.p ... ew&id=5857

[Burgerbob]

A longer slide on a 42? That's a new one.

[Crazy4Tbone86]

Yes......especially considering that the Bach 42 is already one of the longest slides on the market. But, you got to give the customers what they want.......

[harrisonreed]

Student: "I want to play with my tuning slide pushed in more. It's pulled out two inches, makes me look like a n00b, and I can't play low C without losing my F in 1st because for some reason the f attachment is too long and my F is flat. Can I please have the longest slide ever conceived custom made to fix this?"

Teacher: *pushes tuning slide in nearly all the way in*
"There you go"

Student: "but my low C"

Teacher: *pulls F attachment slide out three inches*

Student: "but now I'm not in tune. I need some sort of way to tune my trombone..."

Teacher: *points at the handslide, already the longest tuning slide on any instrument. Shrugs*

[hornbuilder]

Use muriatic acid to remove chrome plate with no damage to the underlying material.

Why did you need to cut the stockings?

[Crazy4Tbone86]

MK sent the tubes to me very long and untrimmed per my request. The inner tubes had about 2 inches extra tubing on the stocking end. When I trimmed them I made the stockings about 1/8 inch longer than normal. I chamfered the end just slightly.

I was taught the muriatic trick years ago. Just always feared accidentally getting the acid on another part of the slide. After today, I am seriously thinking muriatic acid is the way to go. This was, by far, the toughest chrome plating that I have ever faced.

Like I said, it is actually a good thing. In an age when the metal in many mass-produced instruments seems to be of lower quality, this is obviously high-grade chrome plating and should last many years.

[tbonesullivan]

That's pretty interesting. I always thought that the stockings would be cut and have the chamfer added prior to chrome plating. Learn something new every day.

[Doug Elliott]

I have never seen stockings that were cut after chrome plating.

[Crazy4Tbone86]

I have a lot of trombones sent my way with inner slides that are very chewed up on the ends. I have a little jig that holds the slide at exactly a 90 angle to my disc sander and I trim the ends the slightest bit (probably only a few thousandths of an inch) to make them smooth. Then the inners need to be chamfered slightly with a drawing plate and finished with a deburring tool. The tip of the inner slide never has contact with the outer slide because of the chamfer. Thus, no need for chrome plating on that thin circle of metal.

Actually, when I bought my Edwards trombone in 2002, I got home and noticed that both of the inner slides on my brand-new trombone had very rough edges. I did my disc sander/drawing plate/deburring tool routine on it and the inner slides had a smooth-finished edge. Even now, 18 years later, that slide is perfect.

[Crazy4Tbone86]

Want a good example of a chewed up inner slide? Go to the "What Compound for What" thread in this Modification and Repair section. In the background of the photo you will see the ends of a Bach inner slide. One of the ends is particularly chewed up. That slide needs "the disc sander treatment!"

[Elow]

Want a good example of a chewed up inner slide? Go to the "What Compound for What" thread in this Modification and Repair section. In the background of the photo you will see the ends of a Bach inner slide. One of the ends is particularly chewed up. That slide needs "the disc sander treatment!"

It’s just super bent up. Whoever had this horn before me did a really just terrible solder job, like solder literally everywhere. It’s out of round too so i’m planning on putting it on a slide mandrel and hammering it into round or we have a flute thing that rounds out head joints so i’ll see if it fits

[Crazy4Tbone86]

Actually, those look like outer tubes to the F-attachment tuning slide. Sorry...my mistake. Yep, those will need to be cleaned up before reassembly. If there are tears in the metal, it's usually best to cut those down. The problem is that you lose those trim cuts (lines near the end). Sometimes I cut new trim lines, sometimes I just assemble it without making new cuts.