 The Clarinet BBoard
|
Author: Vova Doob(UA)
Date: 2012-07-21 17:10
Hi! I have a problem. I bought old Selmer Signet on ebay, clarinet is good but i can`t remove few key rods because thread is broken. How it`s possible to remove rods without cutting the "key rod holder" and making new thread (sorry, I don`t find this word in vocabulary, hope, You`ll understand).
Thank You!
|
|
Reply To Message
|
|
Author: Caroline Smale
Date: 2012-07-21 18:46
Do you mean the thread is stripped i.e. the rod turns but doesn't come out?
With most rods you can access the end of the rod on the threaded end and apply pressure using a small diameter tool such as a thin piece of rod or thick wire or small screw driver etc. whilst still turning the slotted end of the rod to unscrew it in the normal way.
with those rods with a "blind" end such as the ones holding the left hand E/B and F#/C# levers then it becomes much more tricky, even for a skilled technician, one has to try various approaches too long to describe here.
|
|
Reply To Message
|
|
Author: tictactux ★2017
Date: 2012-07-21 18:59
One possible process in the latter case (inaccessible other end) would be a screw removal drill - it has a slightly conical and reversely threaded head. You need to drill a pilot hole, insert the removal drill and turn counter-clockwise so that it will "bite", and then you can pull the whole shebang out.
With the common diameters of the rods, this is not a funny process.
If the screw head is (partly) broken and no opposite end is available, I succeeded more than one time undoing the key's spring, then turning key and screw synchronously anti-clockwise, then jamming the screw head carefully while "rewinding" the key clockwise to its closed position, then again simultaneously turn key and screw together. Idea is that the friction of the key helps unscrewing and you only work against the screw thread. This works best with partly jammed rods.
If all fails, you have to use a fine saw and cut the rod between key tube and pillar, then carefully rotate the "assembled" pillar until you can pull out the key.
Before doing so, and if the key is otherwise operating fine, try if you can change the pad while the key is still in place. It won't do anything about the messed-up rod, but will buy you a few years with the new pad.
--
Ben
|
|
Reply To Message
|
|
Author: Bob Bernardo
Date: 2012-07-22 12:21
This is a hard one. To save the post and the rod, I have a tool and dye kit. Even with this you will still need to get the rod out. I can get these out with good grabbing plies, but you still need to rotate the rod forcefully when these are striped. Once the rod is out well the fun begins. It is fun, I'm not kidding! You must tap the post according to the rod screw size. If you are comfortable with this go for if. When tapping, you have to screw in one turn, or even a half turn and then release the burs by turning the half turn the other way and blow out the burs. This will assure you to have a clean tight screw and an exact post hole lined up perfectly. Burs can kill the clean holes. You also need machinist type of reaming oils. Using the dye is a bit easier because you can see what you are doing. Of course make sure the tool and the dye are the exact measurements for both. Sounds hard, but it's actually only about a 5 minute precess. It's just learning for the first time and if you have extra parts well go for it. Needless to say, practice on the extra parts first! One try should do it and add a ton of confidence.
When you get the rod out do NOT use LOCK Tight when replacing it. You won't ever gt that rod out! Do the tap system. Actually I can get that rod out of the LOCK TIGHT, by using a special reverse rotating drill bit. Another subject sometime.
There are other ways to do this such as using thin wire. However it works OK, but it's really not the long lasting fix, only because the threads are stripped.
These tap and dye sets can cost a bit, sets can cost a lot so maybe have a repairman do the job. After you buy everything you need the repair will be much less with the repairman. If you have everything, I'd well go for it. It's actually rewarding, some of the harder repairs to do. Yet it really isn't when you have these tools and you practice for 10 minutes. You are looking at about $60 for the kit, $15 for the pliers, Maybe $10 for the machinist oil, and $8 for the air can to blow off the burs and you probably won't ever use these again! : } Use rubber gloves when messing with machine oil. It will most like smoke. The reason for quality oil.
Good luck. Keep us posted. Email me if you need some help.
|
|
Reply To Message
|
|
Author: Chris P
Date: 2012-07-22 12:26
I had a Leblanc Concerto A clarinet in a while back where both the LH lever rod had stripped threads and they couldn't be removed (they'd only rotate). The threads in the pillars had been stripped leaving about half a turn's worth of thread to grip onto due to the rod screws having been over torqued and cross threaded by previous repairers as the heads were mashed up.
I ended up drilling a 1.1mm hole in the screw heads (while they were tight), tapped them with a 12BA tap and screwed in a long 12BA screw to extract them - they could be pulled straight out once they were loose. Then after I drilled out and retapped the pillars (which are sunk deep into the joint by the chimneys), I fitted new rod screws with a larger threads to both of them.
Former oboe finisher
Howarth of London
1998 - 2010
The opinions I express are my own.
|
|
Reply To Message
|
|
Author: Mark Charette
Date: 2012-07-22 12:28
Bob Bernardo wrote:
> When you get the rod out do NOT use LOCK Tight when replacing
> it. You won't ever gt that rod out!
Sure you can. Just don't use the permanent Loctite and if things don't seem be easy to disassemble someday just heat up the joint with a soldering gun or iron (no open flame needed). Heating the joint will even allow a connection made with the permanent type of Loctite to be disassembled safely.
Mark C., former machinist ... Back in the 70s.
|
|
Reply To Message
|
|
Author: clarnibass
Date: 2012-07-22 13:14
>> Sure you can. Just don't... <<
Yes. At worst, if you can't get the screw to thread (e.g. replace it, thread the post, whatever is needed) then Loctite is fine as a DIY or cheapest repair that will work. Just be careful not to get any on the rod or inside the hinge tube. Make sure it is only on the threads.
Not sure, but maybe in the first post he meant the slot is broken? In that case the solution can be different from when the threads themselves are "broken".
If the threads are "broken" i.e. the screw rotates but doesn't come out, others had good suggestions.
You can also try a very strong magnet, if the rod screw is magnetic (some are, some aren't). This even worked for me a couple of times with one ball magnet from a Neocube set, but a bigger and/or stronger magnet can work even better.
Another thing that sometimes works is to hold the instrument so the slot side of the screw is pointing down, then unscrew it with a screwdriver but also push slighty to the side. Sometimes this friction plus gravity will work.
It is also possible to use something relatively sharp to "stick" in the screw slot, so when turning and pushing to the side there is enough friction to pull it out (pointing down for this too can help). It all depends how tight the screw is inside the hinge and/or posts.
|
|
Reply To Message
|
|
Author: vljenewein
Date: 2012-07-22 13:41
Try the simple approach. If you have some of the treaded post sticking out use a small needle nose plier and keep pulling while "gently" moving the main body of the piece you are taking the rod out of. Sometimes they get really tight in there and it 'seems' like they are broken, but they are not, just tough to pull out. Fingers won't do it sometimes. When you get the rods out, and if they are rusty, you can use a Dremmel with a tip that adjusts to 0 and hold the end that DOES NOT have threads firm but tight. Turn on the Dremmel and using a small piece of scotchbrite pinch on both sides at the same time and go up and down the rod avoiding the tread area all together.
Another option, and I have used it on really stubborn screws in gun-smithing, is Kroil made by Kano It is a super penetrant that can penetrate a small as 1 millionth of an inch. It breaks frees stuff, works fast and is a lubricant at the same time. You can also use it to clean the bores of your firearms as well. Kano Kroil comes in an orange can.
Vernon
Jenewein Duduks Manufacturing & Research
www.duduk.us American made Duduks
|
|
Reply To Message
|
|
Author: Chris P
Date: 2012-07-22 17:11
Very often if screw threads have broken off in the pillar, they can be unscrewed by patiently pushing the broken off thread round with a sharp scriber or similarly shaped piece of steel in an anticlockwise direction until enough of the thread is showing and can be gripped with pliers. Rod screws usually rust solid in the hinge tube and moving the keys with seized rods will often show the threads are still free to move.
So if the rod screw can be broken off the thread that's still in the pillar (which does take some doing), then the most troublesome part is removing the rod screw from the hinge tube compared to removing the thread from the pillar. Sometimes the rod screws can be driven out with the help of oil and heat and tapped from the threaded side with a suitable sized punch (making sure it doesn't slip), so try that first.
If all attempts fail to remove both the stuck rod from the hinge tube and the thread from the pillar, then the keys can be boiled in an alum solution for the length of time it takes to dissolve just the ferrous parts. Remove any springs and screws to do this.
If you can't do that but do have spare hinge tubing, rod screws and all the necessary taps and dies (as well as all other tools needed to fit keys) then remove and hard solder in a new hinge tube to the key, drill out and retap the pillar and then fit a new rod screw to the appropriate length.
Former oboe finisher
Howarth of London
1998 - 2010
The opinions I express are my own.
|
|
Reply To Message
|
|
The Clarinet Pages
|
 |
.jpg){kind=small}
.jpg){kind=small}
.jpg){kind=small}
.jpg){kind=small}
.jpg){kind=small}
.jpg){kind=small}
