support Tutorials CDs PPT mouthpieces

Time for pads to settle in

saxyjt

Saxus Circus Maximus
Café Supporter
Messages
5,285
Locality
France
I've just done a couple of repads, one on alto and the other on tenor. After setting the pads with shellac I have set the relevant screws to ensure the linked pads closed properly and replaced/trimmed various pieces of cork and/or felt to bring everything into place. I play tested, fine tuned here and there, always using my leak light to view where it didn't seal. Play tested again. Then let it rest.

The next day, I check with the leak light and some pads that sealed yesterday don't. I have to make a few more adjustments. So my question is, if that is normal and I suspect it is. How long does it normally take for pads to settle in and remain stable?

I must add that I don't apply pressure to the pads to force them in. I read some do that overnight after padding. Should I?
 
Yep, that's normal.
Simply put, any pad and/or key manipulation is going to 'settle' over the course of a day.
As far as pads go, a lot of it is likely due to the transfer of moisture during the heating and cooling phases - though if you're subjecting the pads to any kind of pressure then that too is going to require some resting time.
As for the keys - metal has a degree of elasticity, and while you can mitigate it to some degree by bending a key past the desired point and then bending it back again, it's still going to move of its own accord for a little while longer.
I call it 'sulking'. It's almost as if the horn resents being tinkered with, and throws a bit of a wobbly when your back is turned.

It's very frustrating at first, because you can easily spend half an hour or more tweaking a recalcitrant pad into position - only to find that what was left as a perfectly seating pad looks the next day like Bodger Bill's been at it.
As you can imagine, it's pretty much pointless to dial in the regulation until the pads/keys are stable, and it can sometimes take a couple of days to get to that point.

You can sometimes speed the process up by using a tin of 'air duster' spray. This is the stuff that's used for blowing dust out of computers - but if you invert the can it'll spray out liquid solvent....which acts as a freezing agent. It's butane, so take care not to have any naked flames around...and keep your fingers well away from the jet of liquid, because a 'freeze burn' can be just as nasty as one from a flame.

I personally wouldn't recommend compression seating of any kind if at all avoidable.
It can work, but it can be very unpredictable - and it tends not to last as long as a seat that's made with minimal pressure. That said there can be times when it's the only method that works....but they're very few and far between, and are confined to exceptional circumstances.

So - initial 'rough seat'. Leave overnight, retweak the seat in spot locations. Leave overnight, check and adjust as necessary. The smaller the adjustment, the less resting time needed...and if you have to heat the entire key cup again...it's back to square one. I make most use of the freeze spray during the final adjustment phase.
A great deal depends on where your "That'll do" point is.
 
So a proper repad job will take at least 3 or 4 days.

That's good to know.

I'll play test it tomorrow and take it from there.

I've used some Zheng Hao pads on that one. They are thicker than the roo pads I used last week and not as snug, so dry fitting was a bit of a pain as they fell off the cups all the time. :w00t:
 
This is why many repairers like to stick with one or two brands/types of pad, so that they have a better handle on how those pads act under a wide variety of conditions.
But you're doing the right thing - namely inspecting the work rather than assuming all is well. It's the only way to do it, and it's how you learn which pads/seating methods gives you the best results.

The longer you can stretch that inspection/tweak process out, the better the end result in the long term.
 
There is another variable that I have found in my own pad work. That is inadvertently compressing the felt of the pad slightly in one area while getting it to be level. Overnight the slightly compressed area tends to expand back to it original shape and the "perfectly level" pad from the day before no longer exists. Even movement of .001" will be detected at this level of pad work. Some things I have learned that help are:
  • never touch the leather portion of the pad when straightening keys and only touch the resonator when absolutely necessary
  • use the lightest touch possible when checking the leveling of pads
  • I get better results when the back of the pad touches ever so slightly before the front since the front of the key travels farther
  • I like to use firm flat pads on perfectly flat toneholes and use a slightly heated pad leveling ring to iron the pad and "stretch" the leather
  • To do pad work at this level, it is essential that the keywork be as tight as possible.
Many of the highly respected techs in the U.S. when doing overhauls advertise that they do a rigorous play test, let the sax rest overnight, check and readjust, do another vigorous play test, let the sax sit overnight check and readjust and repeat this sequence until everything locks in. Folks wonder why their overhauls cost more than the local "mom and pop" music store. This is one of several reasons.
 
Those being my own horns, I can continue undefinitely...

It's helpful to jot down a few notes. Divide the pad up into a clock face, set 12 o' clock at the point where the cup arm meets the cup and note down any alterations you make post initial seat. Thus you might write 'Raise 3, 6-8 lower 11'. On your next inspection you might find that, say, 5 and 9 show leaks, which means you may have overpulled 6-8.
Over a period of time it'll give you a sense of perspective.
 
Most techs I know, when doing a repad, want to have the horn at least 2 more days after pads are installed and seated and keywork is regulated. They will often inform the client, when a rush job is needed, that he/she may have to return for some tweaking subsequently....

I appreciate both Stephen and JBT being completely honest about this, and I concur with their comments. I have participated in other thread discussions, other p[aces, where many replies were quite dogmatic and insistent that "when you float and seat the pads right - there should be zero need for having to go back and adjust later - if that is happening, you are doing something wrong ".

...fact is, yeah, you can float/level/seat your pads quite nicely and still have the issues described above happen over a period of a few days later.
 
Case in point. At the last regional NAPBIRT clinic I attended taught by Curt Altarac he said that for a long time after "dry fitting" a set of pads and then installing them in the keycups he was frustrated by how unstable they were and kept changing after installation. One day he discovered the solution that changed everything. He dry fit pads and adjusted the key cups as usual, but then got a fresh set of pads to install in the instrument. He said that made a world of difference in how stable and consistent the pad installation was the next day when he checked. I don't know if the rest of us can afford to do the same, but it gives something to think about.
 
What's a fresh set of pads? :confused2:

Conversely, what's not fresh? :rolleyes:

And how does that make a difference? I'm confused! :confused:
Sorry. A fresh set of pads are ones that are new out of the pad storage bins that have not been handled or manipulated. "Virgin pads" might be a better description. :oops:
 
I tie mine up lightly with elastic bands, to simulate playing pressure and leave them overnight. Regulate the day after and the job stays done. Well...I say done. I never get more than a week or with out something needing a tweak.
 
If you use stronger elastic bands you might get two weeks out of the horn before you'd have to tweak it again. :D>:):sax:
 
Sorry. A fresh set of pads are ones that are new out of the pad storage bins that have not been handled or manipulated. "Virgin pads" might be a better description. :oops:

That's kind of weird as the only manipulation I can think of is checking if they fit and if not put them back in the drawer then pick the next size up or down.

Otherwise, we do manipulate them for dry fitting and that's about it. Or am I missing something?

I tie mine up lightly with elastic bands, to simulate playing pressure and leave them overnight. Regulate the day after and the job stays done. Well...I say done. I never get more than a week or with out something needing a tweak.

I remember seeing somewhere small weights being applied to the keys to keep them shut without excessive force. They were 'blutacked' to the keys!
 
That's kind of weird as the only manipulation I can think of is checking if they fit and if not put them back in the drawer then pick the next size up or down.

Otherwise, we do manipulate them for dry fitting and that's about it. Or am I missing something?

Dry fitting is about more than merely selecting the right size of pad. You'll be looking at pad thickness, alignment from side to side and front to rear and taking note of any anomalies that may have an effect on how the pad seats...such as pearl holder protrusions into the key cups.
In order to do this you may have to do a certain amount of 'working' the pad (and the keys), for which you'll be using many of the same tools that you'd use when properly setting the pads.
As such, the resting rule applies - and rather than go to the expense of using a completely new set of pads you'll probably find that simply leaving a few days between dry fitting and actual fitting will do the job nicely.

I could be wrong, but I doubt Curt throws away a whole set of pads each time - and it's likely that the dry fit set is put aside to rest and new set brought out in order to allow the job to proceed without delay.
 
Dry fitting is about more than merely selecting the right size of pad. You'll be looking at pad thickness, alignment from side to side and front to rear and taking note of any anomalies that may have an effect on how the pad seats...such as pearl holder protrusions into the key cups.
In order to do this you may have to do a certain amount of 'working' the pad (and the keys), for which you'll be using many of the same tools that you'd use when properly setting the pads.
As such, the resting rule applies - and rather than go to the expense of using a completely new set of pads you'll probably find that simply leaving a few days between dry fitting and actual fitting will do the job nicely.

I could be wrong, but I doubt Curt throws away a whole set of pads each time - and it's likely that the dry fit set is put aside to rest and new set brought out in order to allow the job to proceed without delay.

I'm with you there on the idea of leaving it for a day after dry fitting. But to me it was obvious that you used the same pads for both. I never considered using a different set. Perhaps simply because I don't have one! But also because to me each pad is unique and so it has to the same. I even considered marking the pad to make sure it is not rotaded after dry fitting.
 
It's not something I've ever consciously done, but then I often find there's a break between dry fitting and actual fitting due to the way I structure my schedule. I very rarely get left alone long enough to get through a major job without a number of smaller time-critical jobs coming in - which undoubtedly differs considerably from Curt's setup.
 
To perform keycup alignment without having to use a pad in the key cup, I have experimented with using delrin tonehole file pilots in mm and half mm sizes inside the keycups instead of pads. I have them in both .250 and ,1875 thicknesses. My theory is that if the disc has the same protrusion from the cup as does the pad on a layer of shellac it can be a perfectly flat substitute for a real pad.

Jim Schmidt in his video on installing gold pads uses a thin sheet of brass the thickness of the pad protrusion between the key cup and tonehole to check the keycup alignment. I think my system, if I can find a way to make it work, is better because if the disc is snug in the keycup you can see the alignment using a leak light as in the case of seating a regular pad.
 
I'm still fighting some leaks from my job almost two weeks ago. Partly because that pads were so tight that they don't move much. Perhaps I should have applied more shellac too. I'm still not sure about the amount I need to use. When I apply too much it overflows and that's a bit messy even if I currently use clear shellac.

I'm considering using some kind of pivot to place in the centre of the pad so that it finds its proper seating naturally. If you see what I mean...

Wasn't that the idea behind the Conn Res-O-pads?

I'm preparing my next project. My Hawkes & Son XX Century soprano. That'll be a bit of a challenge...

IMG_20190130_171122540.jpg
 

Attachments

  • IMG_20190130_171122540.jpg
    IMG_20190130_171122540.jpg
    81.4 KB · Views: 197

Similar threads

Back
Top Bottom