TromboneChat

My new slide from a higher-end maker that prides itself on quality has the pictured burrs inside the slide crook at the spit valve. Over a month after reporting this defect to the company, and almost a month after being told the repair department would be in touch (and a follow up message saying I hadn't heard), crickets.

I'm reasonably good with tools. For those of you with expertise, is this repair straightforward enough that there's a way you'd recommend I do it myself? (I live an hour away from the nearest repair tech.) Thanks.

There is a tool called a Back Chamfer. It’s pricey but would probably do the job. They have various sizes and you should verify what diameter you need.

https://www.mscdirect.com/product/details/82841040

Holy cow, how did you get that pic?

Seems like it wants an abrassive dent ball rubbed back and forth on it. Or a needle file insert through the valve opening and run around circularly, or maybe a section of screen door spring and a couple dowels to rub it back and forth over the hole. Else a tech to take it apart and do it properly.

One time I had a new horn that somebody forgot to drill out the spit valve hole, so I drilled it myself. I didn't give a single thought to deburring the back of the hole. In an ideal world, I suppose a manufacturer would have a system for that - the tool defintely exists - but seriously, would it matter?

If I were to concern myself with that (and I’m inclined to agree with Doug and probably wouldn’t), I’d use a Noga deburring tool with the hook shaped blade.

baileyman wrote: ↑Mon Oct 14, 2024 2:11 pm a needle file insert through the valve opening and run around circularly

This is the simplest and least expensive way. A small round file does the job quite well.

Doug Elliott wrote: ↑Mon Oct 14, 2024 4:55 pm One time I had a new horn that somebody forgot to drill out the spit valve hole, so I drilled it myself. I didn't give a single thought to deburring the back of the hole. In an ideal world, I suppose a manufacturer would have a system for that - the tool defintely exists - but seriously, would it matter?

It certainly won't hurt anything to deburr it.

Of couse it wouldn't hurt anything unless your hand slips...
Does Noga make something for going through a small hole to deburr the back? I haven't seen it, but then I haven't looked. It's not something I ever need to do.

That is a pretty cool photo! Even a drill bit that is smaller than the hole should knock some of those burrs off if you twist it around diagonally. If that does not work, a tech can run a dent ball through there that is a similar to inside diameter….that would knock those burrs off. Of course, the dent ball trick would not work if it is a Bach 42 design (crook is a larger bore than the outer slide tubes).

Thank you for these responses. The manufacturer has been back in touch and I look forward to resolution. I'm not under the impression the burring noticeably affects how the instrument plays, but it catches the fuzzy end of my cleaning snake and keeps it from entering the rest of the crook.

I would get a really big needle and thread a small piece of sandpaper through it, maybe 280 or 320 grit. Put it in an electric drill and spin slowly just a little bit into and out of the hole. That should clean it up.

Doug Elliott wrote: ↑Mon Oct 14, 2024 7:09 pm Of couse it wouldn't hurt anything unless your hand slips...
Does Noga make something for going through a small hole to deburr the back? I haven't seen it, but then I haven't looked. It's not something I ever need to do.

Yes. It’s not an uncommon need for me. They make both small hook shaped blades and mini reversible countersink blades that reach the back side of a through hole.

bitbckt wrote: ↑Tue Oct 15, 2024 5:49 am

Doug Elliott wrote: ↑Mon Oct 14, 2024 7:09 pm Of couse it wouldn't hurt anything unless your hand slips...
Does Noga make something for going through a small hole to deburr the back? I haven't seen it, but then I haven't looked. It's not something I ever need to do.

Yes. It’s not an uncommon need for me. They make both small hook shaped blades and mini reversible countersink blades that reach the back side of a through hole.

One of the reasons plastic recorders initially sounded so different from wood ones is that the plastic ones had finger holes that were sharp edged (right angles rather than chamfered) on both sides. Seems like that reversible countersink would be an answer to that.