The Trombone Forum

Horns, Gear, and Equipment => Repairs, Modifications and Maintenance => Topic started by: Adagiyo on Aug 13, 2017, 12:01PM



Title: Solution For A Frozen Trigger?
Post by: Adagiyo on Aug 13, 2017, 12:01PM
I got out my horn after around a week of not playing because I was moving into a new house. I was super excited to start playing again but i found that my trigger was completely stuck. I don't have access to a repair man atm are there any solutions I can use at home to solve this problem?


Title: Re: Solution For A Frozen Trigger?
Post by: BGuttman on Aug 13, 2017, 12:17PM
I managed to free a stuck trigger by flooding the valve with valve oil.  If there is a dried up bit of stuff in there sometimes it can free it.

Is the trigger stuck because of mechanical damage or simply stuff inside preventing it from turning?  If there's mechanical damage you will have to wait until a Tech can straighten things out.

Also, is it stuck at the valve or the actuator?  If you disconnect the lever and the rotor seems to work fine, look to some damage to the lever or maybe improper stringing (if a string linkage).

If any of this is more than you can handle, play it without using the trigger for now and get it to a tech ASAP.


Title: Re: Solution For A Frozen Trigger?
Post by: robcat2075 on Aug 13, 2017, 02:04PM
If a horn had been sitting around for a decade rather than one week, I'd be getting out the "PB Blaster (http://www.powerpak.net/Products/PB-Blaster/11oz-PB-Blaster-Penetrating-Catalyst.html?gclid=EAIaIQobChMIwoXH8Y3V1QIVE2t-Ch2OUAXSEAQYBCABEgKFP_D_BwE)" which is something you buy in auto parts stores to loosen corroded nuts and bolts.



Title: Re: Solution For A Frozen Trigger?
Post by: simso on Aug 15, 2017, 09:46PM
If you disconnect the linkage to the rotor (prevents bending) this will allow you better access to apply a back and forth motion applied to the stop arm which is screwed directly to the rotor itself, just do a left right wiggle with your fingers, if its only been a week it should come free very quickly.

If not, off to the repair shop, where they will pull it apart and clean it.

Steve


Title: Re: Solution For A Frozen Trigger?
Post by: Full Pedal Trombonist on Aug 15, 2017, 09:55PM
I would take it all apart as much as you can. If the rotor core is stuck in there squirt some WD40 and keep working at it gently twisting back and forth. And one it gets moving brush and wash it all out with room temp or barely warm soapy water and dry it out before reassembling and re-lubing. Just make sure you get all the WD40 out. If you don't have any or don't want to use it regular light weight rotor oil will work.


Title: Re: Solution For A Frozen Trigger?
Post by: daveyboy37 on Aug 16, 2017, 10:56AM
Completely stuck after a week is somewhat worrisome. Question is where the hangup is. Is the linkage frozen, or the rotor itself?

I would say take it to a tech and have it serviced. When was the last time you had it apart to clean out the crud?


Title: Re: Solution For A Frozen Trigger?
Post by: Gabe Langfur on Aug 16, 2017, 11:08AM
Pour lots of oil down the valve from both directions and let it sit for a while. Then try again.

If you can't get it moving again just by flooding it with oil, you will almost certainly do more harm than good by trying anything else.


Title: Re: Solution For A Frozen Trigger?
Post by: Le.Tromboniste on Aug 20, 2017, 07:31AM
Come on folks, the answer is obvious

1) Take apart
2) Clean
3) Lubricate

If there's still a problem, then go see a tech or explore further solutions...


Title: Re: Solution For A Frozen Trigger?
Post by: BGuttman on Aug 20, 2017, 10:34AM
Come on folks, the answer is obvious

1) Take apart
2) Clean
3) Lubricate

If there's still a problem, then go see a tech or explore further solutions...

If you don't know how to take apart and reassemble a rotor valve correctly you can do a lot more damage and turn a relatively inexpensive job into a major one.


Title: Re: Solution For A Frozen Trigger?
Post by: Le.Tromboniste on Aug 20, 2017, 12:05PM
If you don't know how to take apart and reassemble a rotor valve correctly you can do a lot more damage and turn a relatively inexpensive job into a major one.

It's not like it's rocket science either... It's easy to learn and it takes 30 seconds to do.

Replacing strings on a violin can do damage if you don't do it correctly, but violinists don't go to the luthier every time they need to change a string...


Title: Re: Solution For A Frozen Trigger?
Post by: Full Pedal Trombonist on Aug 20, 2017, 12:39PM
It's not about the simplicity of the job. It's frozen so it also might not come out. Soak it and get it moving then take it apart and clean it.


Title: Re: Solution For A Frozen Trigger?
Post by: watermailonman on Aug 20, 2017, 12:41PM
If you disconnect the linkage to the rotor (prevents bending) this will allow you better access to apply a back and forth motion applied to the stop arm which is screwed directly to the rotor itself, just do a left right wiggle with your fingers, if its only been a week it should come free very quickly.

If not, off to the repair shop, where they will pull it apart and clean it.

Steve

First a lot of oil and then what was described here works. It has happened more than once that my triggers have stuck. I have to many horns, and sometimes a horn has not been played for a month. I have learned and usually remember to switch through all my trigger horns. The Schilke with Hagman-valve is the one that has had most problems. It needs to be played at least once a week. Oil valves regularly and they will not stuck.

/Tom


Title: Re: Solution For A Frozen Trigger?
Post by: BGuttman on Aug 20, 2017, 02:47PM
It's not like it's rocket science either... It's easy to learn and it takes 30 seconds to do.

Replacing strings on a violin can do damage if you don't do it correctly, but violinists don't go to the luthier every time they need to change a string...

It's not brain surgery either, but I know of many people with NO mechanical aptitude and these should be prevented from disassembling mechanical things like triggers.

Example:  A guy I know has a Hamilton stand that is missing the rubber cap.  I told him to get a 5/8" cane tip at the pharmacy.  It was beyond what he could do.  I took one off my stand while he watched and gave it to him.  He's a pretty good trombone player even so.


Title: Re: Solution For A Frozen Trigger?
Post by: watermailonman on Aug 20, 2017, 11:24PM
It's not brain surgery either, but I know of many people with NO mechanical aptitude and these should be prevented from disassembling mechanical things like triggers.

Example:  A guy I know has a Hamilton stand that is missing the rubber cap.  I told him to get a 5/8" cane tip at the pharmacy.  It was beyond what he could do.  I took one off my stand while he watched and gave it to him.  He's a pretty good trombone player even so.

There are people who can't solve problems ;-)

/Tom


Title: Re: Solution For A Frozen Trigger?
Post by: BGuttman on Aug 21, 2017, 05:48AM
There are people who can't solve problems ;-)

/Tom

That's an alien life form to me.  I'm an Engineer and mechanical stuff has always been pretty easy.  Disassembly and reassembly is pretty straightforward.  But sometimes there are special tricks to make things better.  Example is putting that bearing plate back on the valve.  You have to put it on straight or you can really screw things up.  I'm always willing to share any tips and tricks I've learned, but some can't figure them out.  I had a friend who flunked Descriptive Geometry because he couldn't figure out what the back side of the object looked like with a front, top, and side view.  He became a teacher and from what I understand did quite well at it (but obviously not teaching Descriptive Geometry).


Title: Re: Solution For A Frozen Trigger?
Post by: Geezerhorn on Aug 21, 2017, 05:57AM
I have a name for guys like that, "The All-Thumbs Guy".  ;)

Then there's "The Poser Guy", who has all the new, fancy, shiny equipment and can't use it worth a darn.  :cry:

Of course, we all love "The Questions Guy", who can think up the most intricate ways to complicate something simple.  :amazed:

But we digress. Time for "The Digression Guy". No explanation needed.  :evil:

Of course, these are all hypothetical and intended for amusement only! And OBTW: I've been all of them and many more. lol

...Geezer "Bob The Builder"


Title: Re: Solution For A Frozen Trigger?
Post by: timothy42b on Aug 21, 2017, 06:45AM
Come on folks, the answer is obvious

1) Take apart
2) Clean
3) Lubricate

If there's still a problem, then go see a tech or explore further solutions...

0) Look at it for a long time
1) Take apart
2) Clean
3) Lubricate

It may not be necessary to take all of it apart.

Certainly I've completely disassembled stuff only to find out that was totally unnecessary (although fun.  I am an engineer.)  You have two chances of damage, one taking it apart and one putting it back.

The valve can stick because the rotor doesn't turn inside the valve.

But it can also stick with a perfect rotor and valve, because the linkage came to an inline condition.  I've had that happen. 

Before you go taking it apart, see if there's something else that's possible.


Title: Re: Solution For A Frozen Trigger?
Post by: harrison.t.reed on Aug 21, 2017, 08:15AM
It's not like it's rocket science either... It's easy to learn and it takes 30 seconds to do.

Replacing strings on a violin can do damage if you don't do it correctly, but violinists don't go to the luthier every time they need to change a string...

30 seconds? Exaggeration


Title: Re: Solution For A Frozen Trigger?
Post by: timothy42b on Aug 21, 2017, 08:21AM
I'll bet you don't restring one in 30 seconds your first time. 


Title: Re: Solution For A Frozen Trigger?
Post by: BGuttman on Aug 21, 2017, 08:33AM
I'll bet you don't restring one in 30 seconds your first time. 

I've known French Horn players who can string one in an extended rest.  I can't.  Don't do it often enough (thank heavens!).


Title: Re: Solution For A Frozen Trigger?
Post by: Euphanasia on Aug 21, 2017, 08:57AM
What brand of horn is it? I had a Chinese horn that had a rotor that seized after just a few days in the case. Something to do with the metals used. Taking it apart every time I played it wasn't an option, so I got used to drizzling oil down the neckpipe.


Title: Re: Solution For A Frozen Trigger?
Post by: Le.Tromboniste on Aug 21, 2017, 09:13AM
30 seconds? Exaggeration

Hyperbole.

But seriously, with mechanical linkages (I agree, string linkage takes much longer), it doesn't take that much more than 30 seconds to take a rotor apart. You literally have three things to unscrew and one soft mallet stroke to give...


Title: Re: Solution For A Frozen Trigger?
Post by: harrison.t.reed on Aug 21, 2017, 10:58AM
Hyperbole.

But seriously, with mechanical linkages (I agree, string linkage takes much longer), it doesn't take that much more than 30 seconds to take a rotor apart. You literally have three things to unscrew and one soft mallet stroke to give...


Yup, the OP sure is a dummy for asking about it. You're right. He must be a soup sandwich. Since when is rotor maintenance a competative sport? You're basically calling the OP dimwitted, and you pretty much called everyone else trying to help on this thread dumb as well, dude. "Come on folks, this isn't rocket science". Not cool. I know you mean well. You have the right answer, but Bruce knows what he's talking about, too.

If you can reset a valve in 30 seconds, you're either a professional tech BUILDING valves or your bearing plate is so jacked up from trying to rush it that it doesn't seal/seat properly and you've already got a wrecked valve.

I totally agree that working on a valve yourself is a huge money saver and an excellent way to spend 30 minutes to an hour doing (this includes taking it apart, cleaning it, oiling it, snaking the tubes, re-greasing the slide, resetting the bearing plates, AND resetting the bumpers to align the valve properly). Telling someone with a stuck valve (ie, they don't know how to take care of their valve yet but want to learn how) that it takes 30 seconds and sort of implying that they're dumb like you did because they might be worried about doing it ....  brah --- my pointing that out is not hyperbole. It doesn't take 30 seconds to do. It doesn't take 30 seconds to learn. You can completely muck up your rotor if you rush it, especially if it's your first time. The OP SHOULD learn how to do it properly. Nough said.


Title: Re: Solution For A Frozen Trigger?
Post by: schlitzbeer on Aug 21, 2017, 11:54AM
If you don't know how to take apart and reassemble a rotor valve correctly you can do a lot more damage and turn a relatively inexpensive job into a major one.

This applies to slides, piston valves, and stuck mouthpieces too. Horror stories from my tech servicing the local schools usually involve all kinds of stuff. Take it to a tech and have them show you how to clean it.


Title: Re: Solution For A Frozen Trigger?
Post by: BillO on Aug 21, 2017, 12:32PM
Slides?

If you can't take your slides apart, maybe the trombone is not for you.


Title: Re: Solution For A Frozen Trigger?
Post by: Bruce the budgie on Aug 21, 2017, 01:12PM
... one soft mallet stroke

You are all familiar with the story of the tech's itemized bill: for hitting with mallet, $5. For knowing where to hit, $95. Well, if you're unfamiliar with it, we love you anyway.

Seriously, I learned a lot, teaching an adult evening class in bicycle repair at a local high school. One student heard basic instructions on wheel truing, along with appropriate caveats, and came back the following week with rims spinning like they were holding still. Another one, bright and articulate, didn't notice their headset lock ring holding still while the wrench was turning. Different folks, different aptitudes.

Count me with the one who said,
Take it to a tech and have them show you how to clean it.


Title: Re: Solution For A Frozen Trigger?
Post by: timothy42b on Aug 21, 2017, 01:22PM
Take it to a tech and have them show you how to clean it.

We went up to JMU for an event, heard Michael Davis, etc.

Part of the day was a repair tech demonstrating.  He took the valve out of his own horn showing us how to do it.  He sure made it look easy!  But he also explained how to do it without damage, and insisted on a rawhide mallet.

Then he took a beater horn and completely disassembled it with a torch.  very impressive. 


Title: Re: Solution For A Frozen Trigger?
Post by: Geezerhorn on Aug 21, 2017, 01:41PM
We went up to JMU for an event, heard Michael Davis, etc.

Part of the day was a repair tech demonstrating.  He took the valve out of his own horn showing us how to do it.  He sure made it look easy!  But he also explained how to do it without damage, and insisted on a rawhide mallet.

Then he took a beater horn and completely disassembled it with a torch.  very impressive. 

A rawhide mallet is indispensable for me. My Bach mpc doesn't fit properly in my Remington lead pipe? My tuning slide won't close all the way? This fourth metronome is also wonky? My spit valve leaks? There's a fly on my music? The needle on my turntable skips on a vinyl record? So many uses...

...Maxwell Geezer


Title: Re: Solution For A Frozen Trigger?
Post by: schlitzbeer on Aug 21, 2017, 02:00PM
Slides?

If you can't take your slides apart, maybe the trombone is not for you.

Id love to show you the repair history of a certain euphonium out here in the public schools. Vise grips to loosen the valve caps, cleaning the valve slides with brasso (weekly and nice & shiny), and finally, using a rubber hammer to bang the mouthpiece into the receiver, so that the case can be closed.  The father is an engineer in the local shipyard.


Title: Re: Solution For A Frozen Trigger?
Post by: BillO on Aug 21, 2017, 03:21PM
Id love to show you the repair history of a certain euphonium out here in the public schools. Vise grips to loosen the valve caps, cleaning the valve slides with brasso (weekly and nice & shiny), and finally, using a rubber hammer to bang the mouthpiece into the receiver, so that the case can be closed.  The father is an engineer in the local shipyard.
But you can't take your trombone to a tech every time you want the handlside or a tuning slide cleaned and lubed, you'd be there twice a week!  It would be even worse for a player of a valved instrument, they'd be at the tech's nearly daily.

Some people should not play brass instruments.

When I started in school, I remember the teacher demonstrating basic maintenance on every instrument, and then getting each student to demonstrate back to him to prove they got it, before we were allowed to play them.


Title: Re: Solution For A Frozen Trigger?
Post by: Lawrie on Aug 21, 2017, 04:26PM
Hmm, lemme see:
I got out my horn after around a week of not playing because I was moving into a new house. I was super excited to start playing again but i found that my trigger was completely stuck. I don't have access to a repair man atm are there any solutions I can use at home to solve this problem?
No indication of damage here, so it is most likely that whatever valve oil was used has lost its volatile fractions and the wax* has remained and "glued" the valve. 

IF my assumption is correct, then simply dribbling some fresh valve oil down the receiver to the valve and letting it sit for a while will soften the wax and it'll start working again.

No fancy penetrating oils or valve disassembly required.  I would, however, recommend purchasing a better quality oil. 

*For those who don't know, Paraffin is technically a wax and your valve oils, unless silicone, are linear Paraffin based.  Better quality Paraffin has a minimum variation of Carbon chain lengths in its make up and becomes less likely to have this problem.  This is why synthetics have an advantage over naturally formed Paraffins; their chains lengths have much less variation.


Title: Re: Solution For A Frozen Trigger?
Post by: Le.Tromboniste on Aug 21, 2017, 08:50PM
Yup, the OP sure is a dummy for asking about it. You're right. He must be a soup sandwich. Since when is rotor maintenance a competative sport? You're basically calling the OP dimwitted, and you pretty much called everyone else trying to help on this thread dumb as well, dude. "Come on folks, this isn't rocket science". Not cool. I know you mean well. You have the right answer, but Bruce knows what he's talking about, too.

Wooooah wait a minute! First, please don't put words in my mouth.

If you can reset a valve in 30 seconds, you're either a professional tech BUILDING valves or your bearing plate is so jacked up from trying to rush it that it doesn't seal/seat properly and you've already got a wrecked valve.

Did I say I could reset a valve in 30 seconds? I said anyone (not me specifically) can take it apart rapidly (which is a fact), and that it's not particularly hard (also a fact). Can things go wrong? Of course they can. But you can also damage a slide by cleaning it with a rod or snake, possibly more easily than you can wreck a traditional rotor that isn't already damaged, and nobody is saying we shouldn't clean our slides and instead bring them to the tech to be cleaned every couple weeks. Again, you can seriously damage a string instrument if you're careless in routine maintenance like restringing. They still need to be able to do it themselves.

Telling someone with a stuck valve (ie, they don't know how to take care of their valve yet but want to learn how) that it takes 30 seconds and sort of implying that they're dumb like you did because they might be worried about doing it ....  brah --- my pointing that out is not hyperbole. It doesn't take 30 seconds to do. It doesn't take 30 seconds to learn. You can completely muck up your rotor if you rush it, especially if it's your first time. The OP SHOULD learn how to do it properly. Nough said.

Again, putting words in my mouth. I never said anybody was dumb. Or that it was stupid to be worried about doing it (which, by the way, the OP didn't talk about either, so what are you talking about?). My 30 seconds comment was hyperbole, as I've said already. Of course it doesn't take 30 seconds to do, and of course you should take your time to do it correctly. But again, it's not rocket science and being paranoid about it isn't helping the OP, or anyone else either.

That being said, I read back the context, and I will recognized that what was intended as a tongue-in-cheek comment to encourage a bit of DIY was not very delicate. There was some really good advise posted before my comment, and I certainly didn't mean to dismiss it. I sincerely apologize if anybody was offended by it, and I will edit out my comment if anyone asks that I do.

I will say this however specifically for Harrison : if the OP was offended, I will offer my sincerest apologies to them, both here and in private, but I find it a bit presumptuous from you to attack me on behalf of the OP without knowing that they were in fact offended and had interpreted my comment the same way you did (which was a totally legitimate way to interpret it, just...if it's the case, they can let me know). It did sound like YOU were insulted by my comments; then please say it and don't hide behind the "you insulted the OP" line, because I won't apologize to you through them. We can talk and avoid attacking each other.





Now let me temper my comment. It's not a question of being dumb or clever. I was only trying to encourage a little DIY philosophy instead of saying "go see your tech". It really isn't a bad idea to learn to do basic maintenance on our instruments (and it's somewhat lacking in the brass and especially trombone world). My point is, what if your valve got stuck backstage 5 minutes before a performance? Or on tour in a foreign country where you can't have access to a good tech for several days? You don't want that time to be your first attempt at doing maintenance on your horn. Better to have it figured out long before. There's a reason why in the military, they teach you to take apart and reassemble your rifle in the dark.

It certainly took me years before I dared to it myself - a horn player did the valve maintenance on his horn in front of me and said "you really have to be able to do that - do you need someone to oil your slide?" - but man am I glad that I did face it and learn it, because the first time I ever had a valve problem was right after sending my horn for cleaning, the professional tech put it back together wrong (cause they're human and can screw up sometimes too!), and it fell apart in the middle of a dress rehearsal, on Easter Sunday when of course everything is closed. More recently, I apparently forgot to dry out my valve in the big rush of moving to Europe for 9 months (so really, if anyone here is dumb, it's me) - coming back, I found my valve completely stuck in dried mineral oil, had a gig the next week while almost all the staff of my local brass tech shop had gone on vacation before the big school instruments cleaning and repair summer frenzy.

Again, I really didn't mean to insult or offend anyone and am truly sorry if I did.


Title: Re: Solution For A Frozen Trigger?
Post by: Alex on Aug 22, 2017, 01:18AM
I dont tbink anyone has managed to offend the OP. He basnt logged on in a week and probably hasnt read any of tbis.
So my best guess is that be fixed it already and is busy practising.


Title: Re: Solution For A Frozen Trigger?
Post by: BGuttman on Aug 22, 2017, 06:28AM
I dont tbink anyone has managed to offend the OP. He basnt logged on in a week and probably hasnt read any of tbis.
So my best guess is that be fixed it already and is busy practising.


Either that or he tossed his trombone in the dumpster (skip for you Brits) and swore off it forever :evil: :evil: :evil:


Title: Re: Solution For A Frozen Trigger?
Post by: simso on Aug 22, 2017, 07:36AM
Pulling things apart and putting them back together is not for everyone.

Some people are what I would say all thumbs, no matter how well they mean or how hard they try, things just do not go right.

My recommendation is always give something a go, if you feel it's beyond your skill set, definetly hand it off to a professional, no shame at all, a smart person knows their limitations.

Steve


Title: Re: Solution For A Frozen Trigger?
Post by: Le.Tromboniste on Aug 22, 2017, 09:13AM
I agree with that


Title: Re: Solution For A Frozen Trigger?
Post by: BGuttman on Aug 22, 2017, 09:22AM
As someone who has dealt for years with problems other people are encountering, I am a great believer in "make sure the plug is in the wall" type of troubleshooting before I go in.  It's not beyond anybody's capability to look to see if a string linkage is missing or broken or if a flood of valve oil into the rotor may free it up.

There is no shame in having somebody show you how to disassemble a valve but you may need to be shown before you try it yourself.

Again I'd often train my operators to be savvy to the equipment and to do minor fixes as necessary.


Title: Re: Solution For A Frozen Trigger?
Post by: ghmerrill on Sep 08, 2017, 07:20AM
Hyperbole.

But seriously, with mechanical linkages (I agree, string linkage takes much longer), it doesn't take that much more than 30 seconds to take a rotor apart. You literally have three things to unscrew and one soft mallet stroke to give...

This is all mostly true -- except that (a) the mallet stroke may not be so soft, and (b) how soft is "soft"?, and (c) what do you hit with the mallet?, and (d) what if the rawhide mallet doesn't work?  Remember, this is for someone who hasn't done this before and is working on a valve that we already know is frozen in some way (assuming it's not the linkage ).  It's not so much a piece of cake for someone who's doing it for the first time, and maybe using an already problematic valve for your first time learning experience may not be such a wise thing to do.

The first time I disassembled a rotary valve was on my 1960s-ish Amati oval euphonium.  I did it for the learning experience.  I knew the valve had been taken apart in the recent past by a very competent repair tech (in order to remove some play in the top shaft/bushing).  Piece of cake.  Took off the linkage, whacked the shaft "softly" with my little rawhide mallet, and the rotor just dropped out.  Cool!

A year ago when I took apart the valves on my Schiller 7B clone, it wasn't such a piece of cake.  I detached the linkage on the first one, removed the bottom cap, whacked the shaft with my little rawhide mallet, and ... NOTHING.  Hmmm ...  Whacked harder.  Nothing.  Whacked harder ... Nothing.  I don't know if there's a rawhide mallet on the planet that would drive that valve out -- and certainly not with a "soft stroke".

What to do?  Get the plastic mallet and whack the valve shaft?  Possibility of bending the stem or distorting the bushing out of round?  No thanks.  The proper technique is to get a brass punch of the correct diameter, insert it in the screw hole in the top of the shaft, strike the punch firmly (making sure you are holding it STRAIGHT so you don't screw up the threads).  Out to the garage to get the punch ... then whack with my little brass hammer! ... and voila!  The valve drops out.

All because it's a "cheap Chinese horn"?  No, rather because it's a a new-ish horn whose valves hadn't previously been disassembled, and where (despite the "cheap Chinese" part) the tolerances are VERY close.

My point here is that while in many cases taking apart your rotary valve is a piece of cake, there are a number of cases in which it's not -- and in which a novice won't know what it should feel like, how much force to use before damaging the valve, and what technique may be required.  In my case it was a consequence of close tolerances.  But it could as easily have been a consequence of some corrosion in an older (and possibly very expensive) instrument.

But you're not done yet:  you have to RE-assemble the valve, align it correctly, and preferably without pounding something out of round, getting the bottom bushing canted, etc.  This also may require some subtlety.  Sure, you can see how to do this on various sites on the web, but it takes some care (and maybe making some simple "aids" to help out in the task).

I really do encourage people to do their own normal rotary valve maintenance and cleaning (and even smoothing out, etc.).  It's not rocket science.  It's more like repairing a bicycle coaster brake (but a lot simpler).  All the bike books I ever read said (multiple times) "Don't attempt to repair your own coaster brake. This is a job for an experienced professional."  For many people this is probably true.  Many others willing to put the effort into it can learn how to do it very quickly.   But a first-timer working on a seriously stuck valve? Here there be dragons.






Title: Re: Solution For A Frozen Trigger?
Post by: timothy42b on Sep 08, 2017, 07:42AM

All because it's a "cheap Chinese horn"?  No, rather because it's a a new-ish horn whose valves hadn't previously been disassembled, and where (despite the "cheap Chinese" part) the tolerances are VERY close.

Very good post.

Sorry to pick an unimportant nit, but................like the golf announcer, it's what I do.

You meant clearances.  Tolerances are how close to the drawing it actually gets built; clearances are how much room between close fitting parts.  These two can vary independently.  Although, if your tolerances are loose, might want to include some extra clearance just in case. 

I know they're commonly used interchangeably, and the wiki even implies this, but it isn't really correct. 


Title: Re: Solution For A Frozen Trigger?
Post by: ghmerrill on Sep 08, 2017, 10:57AM
Yeah, sorry.  I stand corrected.  I'm all for as much precision as possible, and you're perfectly correct.   :)


Title: Re: Solution For A Frozen Trigger?
Post by: Euphanasia on Sep 08, 2017, 11:35AM
Yeah, sorry.  I stand corrected.  I'm all for as much precision as possible, and you're perfectly correct.   :)

But perhaps he's being a bit intolerant?  :evil:


Title: Re: Solution For A Frozen Trigger?
Post by: BGuttman on Sep 08, 2017, 11:47AM
The issue is that there are some people who are mechanically inclined and can easily master the steps to dismantle and reassemble a rotary valve.  While our Techs are really good at it, it's not the reason we depend on them so much.  They have more valuable talents in other areas.  I can't begin to straighten out a slide, but I can disassemble and reassemble a rotary valve.

There are other folks who are "all thumbs" and shouldn't be allowed inside a mechanism (or maybe even operating it :evil: ).  Those folks need to have the valve repaired by a professional.

And we have kids who don't know which type they are.