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Discussion Starter #1
Anyone interested in discussing key fitting.

Ive been asked a few times and also I help a few poeple here in australia get started doing repairs. Im currently talking with a friend in SA, (about 2000kms away) and hes asked me to do him up a photo tutorial of whats actually involved.

Now theres some people here that may be able to contribute to this topic more than myself, I know curt mentions he has an employee who's sole task is key fitting.

I have a bassoon in at the moment with the worst set of keys Ive ever seen, I was going to use this for the photo tutorial, tommorrow is the weekend, so im not under the pump to do repairs, was going to do the key fitting exercise then. if people are interested I can include the photos and tutorial online here.
 

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Absolutely!!!
 

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Discussion Starter #3
Cool

This is the one Ill do the fitting on tommorrow, I took photos and measurements today.

Like everyone else I would not sit down and measure the tubes etc, Im only doing this for the purpose of the discussion

The key in play
 

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Discussion Starter #5
Ive drawn a quick over view of what we are going to do and how we achieve this, today Ill take photos of each step to show it happening in action.

Side note..Ive also got to pull an engine out of car today so it might be a bit dis-jointed, joys of kids

I dont know why it was resized by the forum, it was only a 100kb to start with, but for some reason its been resized again when importing, downgrades the picture
 

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Discussion Starter #6
The first thing to do, is make sure the posts are square to each other , some filing is required to even these out, just a basic file is all you need.

Ive also used a tool I modified / made for identifying orientation of posts to each other, its sprung loaded and pretty square, anything sprung loaded is not perfectly square but the tolerances on this tool are miniscule to say the least.

Because iof the resizing setup in the forum, Ill mention the following

Pic 1 gauge used to identify out of squarenesss
Pic 2 post filing bottom
Pic 3 post filing top
Pic 4 Gauge showing squareness and orientation of post faces
 

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Discussion Starter #7
Because of the resizing on the forum here, Ill leave them from now on as singular photos

Before commencing key fitment on a bad key you need an assortment of drill rod and dies, JL Smith / Votaw sell to the general public for this stuff, kraus etc also have a good range but there a bit pickier who they sell too so you may not be able to buy from them.
 

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Discussion Starter #9
Use a new rod oversized to eliminate that slight bit of wear that will exist in the centre of the key, Ive gone for 0.081 so .004" larger than the original, the .081 is up against the original fitted hinge rod, it doesnt fit through the key but only goes part of the way through so Ideal.
 

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Discussion Starter #11
Now to cut the thread, the most important bit is to make sure the die to rod is square, no point having a rod with a crooked thread will bind the key up straight away

You can cut the thread any way you want, by hand, by lathe with a steady, or a simple jig for holding a die square to the rod
 

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Discussion Starter #12
Once youve cut the thread, give it a tickle with a file or on the buffer just to remove and thread dags that build on the end of the thread, manufacturers undercut the end of a shank to prevent the need for this when mass producing threads and rods, however we havent so we need to remove the build up.

Also pick a reamer to suit the new drill rod 0.081"
 

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Discussion Starter #14
With a reamed hinge post we can now actually run the threaded drill rod through the post and into the opposite side, if you havent threaded it squarley it will wobble as you insert it through, it can even pry the post out of the body
 

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Discussion Starter #16
With the rod marked remove the rod, cut it at the mark and then file or square the end up my whatever means you have, I also like to run a small radius around the edge as well
 

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Discussion Starter #17
To cut the slot, you just use a jewellers file, simply clamp the rod in avise or between a couple of pieces of wood, Ive also attached a photo of as jig you can use for slotting hinge rods as well, simply run the blade and insert the rod and it will self slot
 

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Discussion Starter #18
Once slotted you now need to fit it to the key, however to fit it, you first need to ream the key so the new rod will pass through the centre of the key
 

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Discussion Starter #19
Now the hinge tube has been reamed we can fit the new rod into the key so that way we can swedge the ends of the key to shape them to the right size and alos to allow the ability to lengthen the key
 

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Discussion Starter #20
Finally time to swedge the key, on the home stretch now

You can use swedging pliers or collets, I personally like collets because it clamps over a distance and minimises the marking on the surface, swedge both sides down with the rod fitted to the key, rotate the key whilst fitted to the swedging tool, this allows the material to redistribute itself, it will also slightly lengthen the key, keep swedging until the rod has no side play,..... but not swedged too tight that the rod wont move
 
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