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The goal of a Mechanical Restoration is to repair it to a point as close too, if not better, than it was when it was first manufactured "Mechanically"
This repair walk through is showing how I do it in my shop, I will show each technique as I appply it during the rebuild, if any keys are the same as previous parts of the rebuild I will not repeat that specific walk through process
This repair walk through is showing how I do it in my shop, I will show each technique as I appply it during the rebuild, if any keys are the same as previous parts of the rebuild I will not repeat that specific walk through process
An example of some of the gaps that exist at the ends of the keys, these keys just move all over the place
Visually assess and remove lower stack keys
The bell brace was not attached as you can see the solder is dark grey, so its been broken for some time, again, it should have been addressed when it was repaired last which apparently was only weeks ago.
With a segmented sax body mandrel from Boehm tools we smooth out any body dents
Sax tube on the mandrel
A key
First key for mechanical rebuilding
First key for mechanical rebuilding
This is a Besson and Co Tenor sax low digit "25XX" serial number which places it around being manufactured in 1926
For a mechanical restoration, I start by splitting and removing the bell from the body
It originally came in for an assessment and manufacture of the low eb keyguard
After assessment we informed the customer it was mechanically worn out
After assessment we informed the customer it was mechanically worn out
It has also had some appalling repairs in the past as well, this key rod is too long, didnt stop the repairer at the time from using it however, 5 minutes it would have taken to trim that down and slot the head properly
Going to Label the repairs as well,
We will call this a Type 1 Repair, this is a repair where we lengthen a Hinge tube that has a good fit to Rod screw
Circle indicates the end gap that exists between post and key
We will call this a Type 1 Repair, this is a repair where we lengthen a Hinge tube that has a good fit to Rod screw
Circle indicates the end gap that exists between post and key
Removing the key, the rod is also gungy and rusty
I stop once its a flat surface, I do not want to cut the whole post away to achieve a nice wide bearing surface, it is IMO totally unnessasary
We spot face the ends of the Hinge tube
Smooth and flat
With some Black texta, I mark the posts
Then with a spot facing tool we surface cut the post
Almost flat / repeat
This was the Screw rod fitted, we will give it a light clean and if no good replace it
Using fine grit polish we buff the rod
Surprisingly it came up clean and no pits in the metal, the screw slot is under whelming, we will rectify that as well
DISCLAIMER
This is a walkthrough of what I do on a mechanical rebuild, it is not a guide that you should attempt to follow without having the skill set required.
This is a walkthrough of what I do on a mechanical rebuild, it is not a guide that you should attempt to follow without having the skill set required.
Rod Screw
Pivot Screw
Hinge Tube
Hinge Rod
Links
Type 1 Repair, A repair where we lengthen a Hinge tube that has a good fit internally to a Rod screw with a key extension
Type 2 Repair, A repair where we lengthen a Solid Hinge rod vee compressing the rod
Type 3 Repair, A repair where we have a loose Rod screw inside a Hinge tube, we swedge the gap with pliers
Type 4 Repair, Sizing and fitting a key spring
Type 5 Repair, A repair where a Singular Support post is worn out, Key rod is loose, we rebush the post and redrill
Type 6 Repair, A repair where we make a new Rod screw to remove wear.
Type 7 Repair, A repair where we have a loose Rod screw inside a Hinge tube, we use a swedging collet to remove the wear
Type 8 Repair, A reciever post has damaged threads, we bush and rethread the post
Type 9 Repair Mis-Aligned Stack post straightened and relocated
Type 10 Repair Reaming / Oversizing a Multi Stack post assembly with hand made Reamer
Type 11 Repair Bushing a Multi Stack post assembly
Type 1 Repair, A repair where we lengthen a Hinge tube that has a good fit internally to a Rod screw with a key extension
Type 2 Repair, A repair where we lengthen a Solid Hinge rod vee compressing the rod
Type 3 Repair, A repair where we have a loose Rod screw inside a Hinge tube, we swedge the gap with pliers
Type 4 Repair, Sizing and fitting a key spring
Type 5 Repair, A repair where a Singular Support post is worn out, Key rod is loose, we rebush the post and redrill
Type 6 Repair, A repair where we make a new Rod screw to remove wear.
Type 7 Repair, A repair where we have a loose Rod screw inside a Hinge tube, we use a swedging collet to remove the wear
Type 8 Repair, A reciever post has damaged threads, we bush and rethread the post
Type 9 Repair Mis-Aligned Stack post straightened and relocated
Type 10 Repair Reaming / Oversizing a Multi Stack post assembly with hand made Reamer
Type 11 Repair Bushing a Multi Stack post assembly