Tech/maintenance My new "DIY" pads...

peterpick · May 30, 2022

my other question would be about pad noise. leather and felt is quite quiet, and i can think of a few people who would object to marimba-type noises emanating from their horns. i quite like it myself, but you know....

this would be a matter of choice of materials, of course. it all sounds very promising, david, though i must say your description of the intial fixing of a pad runs rather counter to your fear of setting a standard pad!

DavidUK · May 30, 2022

Once you have installed one magnet, the way I finally devised, you get the idea and it's quick to do. But of course the main time saving is not having to melt the glue a second time to level a pad.

Then, when all magnets are installed that's all the gluing done... for the lifetime of the horn. Just pull out, and drop in, pads from then on.

Pad noise is very low, quieter than leather.

DavidUK · Jul 12, 2022

Just a general update...

1/ The mechanism has been amended to remove the inner adjustment screw and instead use shims to adjust the height of the backing disc from the screw head.
This is a far quicker solution than adjusting the inner nut and then having to loctite it. There's always a thin spring washer last on the screw thread, bearing on the rear of the backing disc, to stop the nut out front of the resonator from undoing.

In setting up a horn for the first time all pads are inserted with their likely shim washers. To then fine adjust, remove the pad (5 seconds), remove the screw (5 seconds), add or remove shim washers as required in 0.1mm, 0.2mm, 0.3mm, 0.5mm, 1mm thicknesses (most need a 1mm lightweight nylon washer), re-assemble (15 seconds), replace the pad (5 seconds). In total 30 seconds to remove, height adjust, replace. In practice this may need to be done 3-5 times for each pad when adjusting/regulating for the first time. Replacing existing worn/damaged pads (if that occurs over time) just swap the screw and existing washers onto the new pad.

2/ Sealing material to close the tone hole. This is the biggest hurdle. Ideally it needs to be water resistant, air tight, long-lasting, forms a seat but the seat heals back to flat after a few hours (so there's no multiple seat "crossover" leak if the pad rotates and forms a newly positioned seat (pads are seldom concentric to tone holes), has a good feel under the fingers, no bounce back, no stickiness when wet, little noise, allows for some tone hole unevenness. The project will stand or fall on these qualities.

I've tested around a hundred likely contenders for the right material but they're either porous, noisy, have a high compression set (keep a deep seat), sticky, or won't adapt to slightly uneven tone holes. The latter in itself isn't an issue as a horn being overhauled and fitted with new pads would generally have these flattened by a good tech so as to make his/her own life more easier apart from anything else.

I've narrowed down the search now, and working with a UK company, under a NDA naturally, have hopefully managed to factor in all of the foregoing, collecting the first sample of this new material last week. In pre-prototype tests it does very well so now I shall cut the 23 discs for my alto test-bed and see how it does in practice. If you recall I have an identical alto with traditional pads as a control. The plan, if it does work, is to record a tune with both and compare them.

More soon... ish.

DavidUK · Jul 17, 2022

Just finished re-padding the Jupiter alto with the new material.

I took all the previous material pads out, marked them as I went so as to know which was which, then cut the new pads, glued them to new backing discs, with new resos, and new mechanisms. I then copied the backing disc to screw head height from each of the old discs. A small amount of adjustment/regulation as I went.

Just played it for the first time since starting the re-pad and it's perfect, no further adjustment needed. This gives me hope that DIY users will be able to replace their own pads after the first installation by me or a tech (or both), if they're not confident of the change from traditional to "new." They simply pull a pad, remove the nut and reso, put in the new pad already attached to its backing disc, replace the reso and screw. Pop it back in. Job done in 30 seconds.

This new material could be the one. I need to further test the prototype with this new material for moisture (saliva) retention, any stickiness (G# is the likeliest). Also compare it to the 2nd identical Jupiter with its traditional pads for how it plays (i.e. loud, soft, etc). Once I've done this I will put it in front of a pro player, and one manufacturer who is interested, for feedback and any revisions. The journey's not over by a long shot, but it's taken me more than six months to get the material right and hopefully that stage is sorted.

More soon...

DavidUK · Jul 17, 2022

Just bung 'em in any old how...

...then simply press the key. Done...

DavidUK · Aug 10, 2022

Update:

I took my prototype alto to one of my techs, Paul Carrington, last Saturday. He played it up and down, said it played fine, and the only criticism he could make was relating to debris getting in behind the pad via the 0.5-1.0mm gap around the pads, between their edges and the lip of the key cup.

He's meaning food debris which might spill out of an open tone hole, dribble its way around the bottom of the pad's face, and somehow move back into the cup.

I can't close this gap entirely as the pad needs to be able to self level. The space between the back of a pad and the inner face of the key cup is 3.5mm minimum.

I'm not sure how much of a real issue this is. How likely it is to happen. But I have to assess and deal with any possible problems a player might encounter.

What are YOUR thoughts, if you can understand the mechanics here, of the likelihood debris will accumulate behind a pad?

Of course, each pad can be removed, cleaned, and replaced, but not so easy is the inside of the key cup itself. This is really only an issue in retro-fitted pads. For newly manufactured horns using my system there is no need for a key cup at all so no harbouring debris. I'm still toying with the idea of cutting away retro-fitted pad cups on another test horn, just to show what's possible so far as weight saving, decoration, and "debris escape" and have just bought a cheapie Windcraft alto (£40, slight bell lip bend) which I hope nobody minds be butchering in the name of experimentation/progress. Otherwise my Yamaha Vito might have been in the firing line, or one of the cheap vintage tenors I picked up.

Paul did also comment on the percussive noise of the pads closing, or rather the lack of it, but recognised it just sounded different and therefore caught his attention.
Less noise was one of the desirable attributes I was looking for in development.
It's less noisy because the synthetic sealing material has a little more buffering effect than leather and felt. This in turn may mean a new user finds a different feel and sound to the pads. In side by side testing with a traditionally padded identical alto I've struggled to detect a difference in feel, only sound, but others who do find some change to feel are likely to acclimatise in the same way they would a new horn.

Next week: ...the Prototype is off to meet a maker. More news soon...

mizmar · Aug 10, 2022

DavidUK said:
What are YOUR thoughts, if you can understand the mechanics here, of the likelihood debris will accumulate behind a pad?

My question wouldn't be the likelihood or amount as such, but the chance of something falling in and jamming things so the pad won't level.... Impact, if you will, analysis. Maybe it'd only take a grain of grit? Maybe a chunk of donut (thus ruling out use in a police band)?

DavidUK · Aug 10, 2022

mizmar said:
My question wouldn't be the likelihood or amount as such, but the chance of something falling in and jamming things so the pad won't level.... Impact, if you will, analysis. Maybe it'd only take a grain of grit? Maybe a chunk of donut (thus ruling out use in a police band)?

The gap isn't big enough for something to fall in. It would have to surf in on a globule of spit. Using a pull through could dislodge a piece of donut from the tube inner and scrape it off on one of the pad edges.
You'd know about this, in the same way you'd know if the donut was lodged in your current set up.

Traditional pads I've removed often have debris stuck into them, particularly in the seat. This isn't as easy to clean as with my new pads but if the donut gets behind one of my pads you'd have to first pop the pad out, clean it and perhaps the cup behind, re-insert pad and off you go again. Not a big deal and probably equal to the faff of having something stopping a leather pad from closing entirely and trying to get the culprit debris out without having to dismantle half the horn.

mizmar · Aug 10, 2022

DavidUK said:
Traditional pads I've removed often have debris stuck

Ok. So my question is; of this debris could any of it stop the pad levelling by, for example, getting into the ball joint (if I've understood where we are?)? If not - if you can go "here's a years worth of debris from a jobbing Sax and none of it stops the pads levelling" you'll answer his question. No?

Pete Thomas · Sep 14, 2022

I now have David's prototype Jupiter in my possession. I am not in the best shape to play at the moment due to health (which seems to be improving) but initial thoughts are that it plays like a saxophone. If I didn't know there were magnetic pads in there then I wouldn't have guessed it was anything but a "normal" saxophone.

I will hope to give it some rigorous testing as soon as possible, but so far I'm impressed. You can play it, take a few pads out with the thoughtfully supplied tweezers and put them back in all within a few seconds and it plays just the same. No apparent leaks (but that is where the more rigorous testing will come into play.

I've invited a couple of players round to have a go, one of whom is a member here.

So watch this space. I would be very interested to see what techs think of this though.

Stephen Howard · Sep 14, 2022

Pete Thomas said:
So watch this space. I would be very interested to see what techs think of this though.

You know where I am... 🙂

PigSquealer · Sep 14, 2022

Stephen Howard said:
You know where I am... 🙂

Did you move to the high rent district ? I didn’t think the new facility has a music store.

Pete Thomas · Sep 15, 2022

Stephen Howard said:
You know where I am... 🙂

Probably not in a position to travel that far at the moment, but if you are in the area do pop round

Woodpad · Sep 16, 2022

Pete Thomas said:
No apparent leaks

When the pads seal perfect the lowest harmonic can be stronger. This sounds like less projection. When you invite other players could you ask them to bring their loudest mouthpiece as an extra to compensate for this?

jbtsax · Sep 16, 2022

Woodpad said:
When the pads seal perfect the lowest harmonic can be stronger. This sounds like less projection. When you invite other players could you ask them to bring their loudest mouthpiece as an extra to compensate for this?

I'm not sure what you mean by that. Can you explain?

Trigger · Sep 16, 2022

I actually met Dave and saw these pads first hand at Paul carrington repair shop , they seem to do exactly what Dave says and even Paul was impressed when he played the Jupiter sax with the pads fitted ,
So a great idea and product , but think most repair guys will be sceptical as it could mean less repad jobs for them if they take off

Pete Thomas · Sep 16, 2022

Woodpad said:
When the pads seal perfect the lowest harmonic can be stronger. This sounds like less projection. When you invite other players could you ask them to bring their loudest mouthpiece as an extra to compensate for this?

Based on what David told me, (possibly small leaks on a couple of tone holes plus what can go wrong with shipping) I am not expecting 100% perfect pad seal on all the pads on this prototype retrofit, that isn't the point. Maybe it does, maybe it doesn't. I'd be surprised if it does after shipping anyway.

I am basically looking at the system I see in front of me me and cannot do a review of a specific product that is not in production or advertised to be or do anything.

So far it does seem to do what you would hope for, ie swap out a pad in a few seconds

Trigger said:
think most repair guys will be sceptical as it could mean less repad jobs for them if they take off

I don’t think it is that simple. Unlike conventional pads these rely absolutely on level tone holes and key cups. Softer leather pads with shellac or glue can be made to seal by shims or floating, these can’t.

Hence there is still plenty of work for techs dealing with the integrity of the tone holes and key cups.

Trigger · Sep 16, 2022

According to Dave these pads will seal even if the tone hole isn’t level

I can’t say for sure just passing on what I was told
But the question is would replace the leather pads on a mkvi with them , I don’t think I would and I know I would always take mine to a decent repair guy ,
But for school instruments etc you can see the benefits

Pete Thomas · Sep 16, 2022

Trigger said:
According to Dave these pads will seal even if the tone hole isn’t level

Level may have been a poor choice of word. I get the feeling but cannot verify yet they could compensate for a certain amount of not being level, however it may be a different matter if they are actually warped,

DavidUK · Sep 16, 2022

These could be fitted "DIY" but in reality most owners won't wish to dismantle, re-pad, assemble, adjust and regulate.
@Trigger - they are able to cope with a degree of tone hole unevenness but it's impossible to predict how any "uneven" tone hole presents itself. It might have a dip one side, or be twisted. So I can only advise that tone holes should be levelled prior to fitting.
As the sax has to be dismantled, once, to fit the magnets, tone hole levelling ought to be part of a tech's standard approach to a re-pad.
I created these to satisfy my view that traditional pads are outdated and a faff to fit and lack adjustability thereafter. They do perhaps cater for uneven tone holes when fitted by a tech but bending pads or shimming them to do this I feel is a bit if a bodge. Flat tone holes, flat pads, that has to be best.
One real advantage comes when swapping out pads or changing resonator type. Little dismantling required, just pop the pads out and replace.