Keyboard axle removal via electricity

[tcabot]

I wouldn't mess with keyboard axle unless absolutely necessary.

Not sure if anyone mentioned this already: you can drill a hole opposite the other end of the axle and drive it out with an appropriately sized punch. Just drive it out enough to be able to clamp the other end in a vice, then twist and pull.
Be prepared to have to re-glue broken parts of the keyboard and install new axles.

 

[Mr Mark]

Hi Mark
I might be able to find a rod of brass later and do an experiment.
However as per my rough estimate 10A wouldn't be enough (20A neither) - that's why some came to the idea taking a car battery.
The diameter matters a lot as it factors in by square; also brass comes with ca. half the specific resistance over iron.
The axle will end up in single-digit mOhm (that's why wiring and clamps are important - they should come with even less mOhm).
Even if it was 10mOhm and you manage to dissipate 10A through the rod - that's only 1W.
You may be able to measure the temp-rise with a very precise instrument but presumably it won't (by far) not be enough to get the desired extension effect.

Thanks PhiliGol, Your specific math/electrical knowledge is better than mine - having said that it seemed my rudimentary knowledge indicated this would be the case anyway. I appreciate the time you have input!

I have drilled a hole in the other end, that gives you the option of carefully tapping it in both directions.

I am afraid that being brass I will mushroom the head easily and thus have created another problem. Not out of the realm of trying but will be one of the latter options if need be.

I can't help with the problem, but I am having fun trying to visualise what's happening. Does the axle pass through a hole in each key? So if the axle was stuck within a key then either the key would be stuck, or the axle would rotate when the key was pressed? So the axle must be stuck at the far end? Or have I missed something...?

The axle does indeed pass through each key and also passes through holes in the accordion frame (for lack of better terminology). None of the keys are stuck, however the rod does pass through 70 different pieces of wood along the way, my guess is that with time (85 years) enough grime has built up and/or corrosion and/or swelling of the wood that collectively all these points are holding well enough to neccesitate ulterior means of removal.

I wouldn't mess with keyboard axle unless absolutely necessary.

Not sure if anyone mentioned this already: you can drill a hole opposite the other end of the axle and drive it out with an appropriately sized punch. Just drive it out enough to be able to clamp the other end in a vice, then twist and pull.
Be prepared to have to re-glue broken parts of the keyboard and install new axles.

As per above, I have a fear that the brass will mushroomhead with tapping, however is not out of the realm of trying once I've exhausted trying other things.

 

[Mr Mark]

Mr Mark:
I’m reading responses to your problem with interest. I’ve had mixed success, on some occasions been completely stumped, usually on very old instruments.
I recently had success in a repair to a split wooden frame supporting a PA keyboard (highlighted elsewhere on this forum). The key to the success was using a blunt nosed syringe to get glue to places which would otherwise have been inaccessible. While reading this thread I thought of the syringe. It’s needle is approx 2mm dia. so a hole drilled to allow its access is very small, unobtrusive and easily covered later if need be.
A carefully drilled hole will give direct access to the seized axle passing through its wooden supports. A liquid ‘lubricant’, such as WD40, would have the double benefit of lubrication and expanding the wood. I believe the expansion of the wood would temporary only and it it would soon resort to its previous form.
Just a thought.....

Hi boxplayer4000,

debra and yourself have mentioned this approach and I'm going to give it a go. This may or may not coincide with giving the sealed end a few gentle taps with the right sized punch. Direct injection to each location will be better than my previous methods. Indeed, these old boxes are tough, I have a couple others this vintage I thought I would try a bit with and they all have the same issue.

No major damage done yet!

 

[Dingo40]

and also passes through holes in the accordion frame (for lack of better terminology).

The "comb"?

 

[Dingo40]

...A liquid ‘lubricant’, such as WD40, would have the double benefit of lubrication and expanding the wood. I believe the expansion of the wood would temporary only and it it would soon resort to its previous form.
Just a thought.....

There's WD40 and WD40 in different formulations.
I would not advise using the "penetrating oil" formula as this contains petroleum products and would likely cause permanent damage to wood.
On the other hand, I'd be happy to use the WD40 PTFE formulation shown here:

Dry Lube Spray - Dirt & Dust Resistant Dry Lube | WD-40

Reduce friction and provide long-lasting lubrication with the dry lube spray from WD-40. This formula dries quickly and resists dirt and dust. WD-40 Dry Lube Spray is great for door and window tracks, slides, belts, rollers and hinges.

www.wd40.com

BTW,it's also excellent for light switches and cupboard and wardrobe locks!

 

[tcabot]

You know you've been doing too much DIY when you ask your Mrs to wear WD40 as perfume on a night out...

Mushrooming is a risk, but heating the axle is a risk too. There's nothing good about removing old axles

 

[Rosie C]

The axle does indeed pass through each key and also passes through holes in the accordion frame (for lack of better terminology). None of the keys are stuck, however the rod does pass through 70 different pieces of wood along the way,

Ah, of course, and the axle won't have moved in the frame holes. It all makes sense now

 

[Ventura]

Ah, of course, and the axle won't have moved in the frame holes. It all makes sense now

and you may as well finish the visualization with this

you are seeing one axle, but you have certainly noted the white keys are
rather long compared to the black keys, so obviously the optimum geometric
"pivot point" for those 2 different lengths would be a bit best served with
separate rods and engineered angles

hence the higher level "pro" keyboards design in 2 pivot rods, 2 combs,
and can be pulled and worked separately from each other

the object being to smooth out the touch so your fingers/muscles
do not hit that "steep" angle between sharps and naturals, which
allows the artist a quicker more natural response and feel

and once you feel that difference you quickly find
it is preferable to a player who likes to be light on her fingers

a similar kind of pro difference is found in grand piano's between
the home furnishing line and the actual professional performance
or teacher's models

 

[PhiliGol]

Hi Mark

First of all I want to mention that I'm not an accordion technician.
Best case I'm a decent player on amateur level who does some "maintenance" as needed.
On the instruments inside I'm stopping at the reeds, i.e. I can takeout a reed block to remove a particle blocking a reed in case but I refrain from touching the reeds/valves itself. Subsequently I can't judge the methodology heating up the keyboard axle per se, I'd rather follow the advice from experts like Paul (de Bra) or other professional accordion techs on this forum.
On the other hand drilling a hole or punching one of my instruments sound so hurtful, therefore I followed up on the experiment I promised earlier.
I didn't find a brass rod but a 2mm copper rod. Copper comes at ≈1/3 of brass' specific resistance, on the other hand 3mm over 2mm diameter results in an impedance reduced by factor 2,25 - so the experiment is valid for your 3mm brass axle. I fed 10A through a 40cm piece of the copper rod presuming that's close enough the length of your instruments axle (longer would help). The rod warms up but honestly I doubt that this gives enough heat to cause the desired effect.

The extra instrument displays the voltage drop over the feed-points resulting in a dissipation power of ≈2.3W.
That's obviously too low to cause a significant temp-rise. The total power fed into the "system" (banana-plug - forward cable - clamp - "axle" - 2nd clamp - return cable - 2nd banana plug) is 1.0V x 10A = 10W (the power-supply readout). Despite 3/4 of the total power is "burned" by cable/plug and clamp it doesn't heat up since it distributes over a long cable.

Different story when I crank it up to 20A: that's enough to heat it up so that after ≈30s you don't want to touch it any longer.
Also the thermal-coefficient helps: the hotter it gets the rods impedance increases, since current remains the dissipation power increases - you need to take care to not end up in a thermal runaway.

So if you want to pursue this way prior hammering or drilling your box and you're willing to invest into a lab-power supply: why not buying 2 10A models and connect them in parallel? That gives you 20A which you can control nicely by the "constant current"-knob.

And finally isn't it a bit the same with power-supplies as with our instruments? You can NEVER have too may of 'em

 

[tcabot]

without reboring a larger sized rod as I do not have the capabilities

Do you have a drill?

You just need a regular axle (slightly larger than you had before), put a flat spear point on it with a hand file (don't make the spear point wider than the diameter of the new axle), chuck the blunt end of your newly made reamer into your hand drill and re-bore the axle. When things started heating up for me, I used some candle wax on the rod to reduce the friction - not sure if that's a good idea or not (but why not?). You can probably use graphite powder instead.
The spear point allows you to use the existing holes as a guide, and even allows you to re-drill new holes quite accurately if you had to repair the comb and lost a couple of the original holes.

You'll be done in 10 minutes.

PS as a matter of fact, if you are using 2.0-2.5mm stiff and relatively short axles, you should be fine with zero clearance but if your axle is anything like my Morino (1.2mm brass originally) and you're expanding it to, say, 1.6 brass, reaming it in & out of the slot is fine, but putting the actual axle into a zero-clearance slot can be a challenge when it's so thin, flexible and long. You might want to very very very gently tap the tip of your home-made reamer with a tack hammer and expand your spear tip from 1.6 to 1.65mm. Don't overdo it!

 

[Dingo40]

You can probably use graphite powder instead.

All good suggestions except I'd stay well clear of graphite powder: it goes everywhere and it makes a major mess! Very "grubby" and hard to clean up.
Candle (paraffin) wax or an off the shelf "dry lube" much better, in my opinion.

 

[Mr Mark]

There's WD40 and WD40 in different formulations.
I would not advise using the "penetrating oil" formula as this contains petroleum products and would likely cause permanent damage to wood.
On the other hand, I'd be happy to use the WD40 PTFE formulation shown here:

Dry Lube Spray - Dirt & Dust Resistant Dry Lube | WD-40

Reduce friction and provide long-lasting lubrication with the dry lube spray from WD-40. This formula dries quickly and resists dirt and dust. WD-40 Dry Lube Spray is great for door and window tracks, slides, belts, rollers and hinges.

www.wd40.com

BTW,it's also excellent for light switches and cupboard and wardrobe locks!

Funny thing about WD40...as a kid growing up poor in a remote northern community I had mostly crappy $5 bicycles at from garage sales I was always having to fix or improve upon - this was the start of me learning how to fix things. My grandfathers, uncles etc all swore by WD40 as a lubricant, it didn't take me long to figure out it was absolutely the worst stuff to put on a bicycle because of all the dirt that stuck to it. I've never owned a can since, this PTFE is definitely different though, so you never know.

Hi Mark

First of all I want to mention that I'm not an accordion technician.
Best case I'm a decent player on amateur level who does some "maintenance" as needed.
On the instruments inside I'm stopping at the reeds, i.e. I can takeout a reed block to remove a particle blocking a reed in case but I refrain from touching the reeds/valves itself. Subsequently I can't judge the methodology heating up the keyboard axle per se, I'd rather follow the advice from experts like Paul (de Bra) or other professional accordion techs on this forum.
On the other hand drilling a hole or punching one of my instruments sound so hurtful, therefore I followed up on the experiment I promised earlier.
I didn't find a brass rod but a 2mm copper rod. Copper comes at ≈1/3 of brass' specific resistance, on the other hand 3mm over 2mm diameter results in an impedance reduced by factor 2,25 - so the experiment is valid for your 3mm brass axle. I fed 10A through a 40cm piece of the copper rod presuming that's close enough the length of your instruments axle (longer would help). The rod warms up but honestly I doubt that this gives enough heat to cause the desired effect.

The extra instrument displays the voltage drop over the feed-points resulting in a dissipation power of ≈2.3W.
That's obviously too low to cause a significant temp-rise. The total power fed into the "system" (banana-plug - forward cable - clamp - "axle" - 2nd clamp - return cable - 2nd banana plug) is 1.0V x 10A = 10W (the power-supply readout). Despite 3/4 of the total power is "burned" by cable/plug and clamp it doesn't heat up since it distributes over a long cable.

Different story when I crank it up to 20A: that's enough to heat it up so that after ≈30s you don't want to touch it any longer.
Also the thermal-coefficient helps: the hotter it gets the rods impedance increases, since current remains the dissipation power increases - you need to take care to not end up in a thermal runaway.

So if you want to pursue this way prior hammering or drilling your box and you're willing to invest into a lab-power supply: why not buying 2 10A models and connect them in parallel? That gives you 20A which you can control nicely by the "constant current"-knob.

And finally isn't it a bit the same with power-supplies as with our instruments? You can NEVER have too may of 'em

This is awesome, thanks so much for the experimentation - this is the ends of the earth sort of experimentation I am into just for the sake of knowing, but is truly well and beyond my means. You have on the other hand, explained how this is actually possibly within my means. I may get there on way or another (on a beater box to start) just for the sake of trying, the cost of the experiment is not beyond my means, thank you!

Do you have a drill?

You just need a regular axle (slightly larger than you had before), put a flat spear point on it with a hand file (don't make the spear point wider than the diameter of the new axle), chuck the blunt end of your newly made reamer into your hand drill and re-bore the axle. When things started heating up for me, I used some candle wax on the rod to reduce the friction - not sure if that's a good idea or not (but why not?). You can probably use graphite powder instead.
The spear point allows you to use the existing holes as a guide, and even allows you to re-drill new holes quite accurately if you had to repair the comb and lost a couple of the original holes.

You'll be done in 10 minutes.

PS as a matter of fact, if you are using 2.0-2.5mm stiff and relatively short axles, you should be fine with zero clearance but if your axle is anything like my Morino (1.2mm brass originally) and you're expanding it to, say, 1.6 brass, reaming it in & out of the slot is fine, but putting the actual axle into a zero-clearance slot can be a challenge when it's so thin, flexible and long. You might want to very very very gently tap the tip of your home-made reamer with a tack hammer and expand your spear tip from 1.6 to 1.65mm. Don't overdo it!

tcabot,

This makes good sense. I suppose I may have been overthinking this with the thought of some crazy big drill press and some kind of rare and expensive drill bit. I may just try this on the box I have already zapped just to see. Thanks for the simplification of explanation!

 

[Aaron]

Does anybody make an accordion which has both a teflon coated rod and teflon-bushed keys? I wonder how many years it would take for a player to notice any degradation in key action.

 

[Ventura]

not long

Steinway had a bright young man who once thought the same thing

it was a very costly disaster, requiring a recall and replacement

there are good reasons why traditional materials and the test of time
should not be messed with

 

[Dingo40]

Does anybody make an accordion which has both a teflon coated rod and teflon-bushed keys?

Why should anyone make something to last 150 years when 80 years will do?
Many things, nowadays, are made to just make it through the warranty period!

 

[Ffingers]

Why should anyone make something to last 150 years when 80 years will do?
Many things, nowadays, are made to just make it through the warranty period!

...and frequently fail even that criterion.
Then they try to weasel their way out of warranty by accusing the consumer of all kinds of mischief.

 

[tcabot]

I thought of using tiny ball bearings actually. Then you don't need an axle. You push-fit a ball bearing into the aluminium key rod, then mount each key individually by riveting it to a post. Similar idea to concertinas, but with bearings.
Benefits? Well, you don't need to take the whole assembly out to replace felt on one key. Each key can be adjusted individually. Smooth action with no sideways play in it. The question is - how long will the bearings last (can the lube inside them get sticky after several years?). A bit of extra weight and a bit of extra manufacturing costs.

Maybe one day I'll try it.

 

[Snoopz]

can the lube inside them get sticky after several years?

Yes, very much so. I don’t know the English word, but in German it’s „verharzen“ meaning that most fatty lubricants turn to something like resin given enough time.

Another issue: bearings are heavy! Sticking a metal shaft through a relatively thin brass bushing removes all the balls, races and covers from the game. And you don’t want open bearings to catch dust over the, say, 80 years of life?

 

[tcabot]

689-2RS are very small, lightweight and sealed. a 2mm steel shaft with a bunch of solid brass bearings might actually be heavier. Lube is the only question, and, arguably, pressing new identical bearings in every 40 years is not a very expensive repair. Easier & faster than re-boring for a new axle.

There's a bit of controversy about the 80 years comment, imho. Firstly, if the accordion is played regularly, the bearing & axle wear will happen a lot sooner. My "project" Morino club is 70 years old and it's been played until holes in celluloid. The brass axle was completely chewed by the brass key rods. I say a good 0.2mm wear on the axle & key rod combined, if not more. Secondly, nobody buys a top of the range laptop expecting it to last 80 years. Or car. Or fridge. Or garden shed. So why is it that people want their relatively cheap musical instruments to last for 300 years and play perfectly during all this time?

 

[Snoopz]

So, what's the difference between replacing a bearing and replacing a rod and some bushings? Since you want to pull up all the keys every 40 years anyway, why go to the trouble of putting a bearing in every key with some mechanism to hang keys individually (how you want to achieve that without introducing a failure point is still unclear to me)? You probably won't get a stuck axle after 40 years anyway, so no advantage for bearings. Also: Brass bushings and a new rod will come way cheaper then 40+ sealed bearings, so your "cheap repair" argument is flawed.