To wax or not to wax.

[Orchorsol]

That's what you did in first place. Bronze is not a compound that gives any problem with mold. Most bronze statues are left in open air exposed to wind rain and snow all of the time and some of them are >2K years old and they still look good. So you can basically do whatever you want with bronze. Not the same with shellack. Also, most museums have air conditioned if not computer-controlled temperature and humidity, so that molds will never grow in any case. That's not what happens in a normal house during a prolonged rainy spring or a foggy fall.

Early cylinders made with a wax-based compound are very well known for the problems that most of them have with mold growth, and as a result few of them are still listenable today. Shellack is less critical from this point of view and is more easily preserved over long times, if kept clean. Who plaster shellack with wax has forgotten the old lesson from the early cylinders, IMHO.

This said, perhaps yes: if you live in Arizona you will likely have less problems with mold than folks who live in London...

I think it may depend on the type(s) of wax Marco. Amongst the many records I buy, I sometimes find ones which a previous owner had treated with wax many years ago (the wax tends to be readily visible in smears, unlike the treatment I give some records). These are invariably classical records in fine condition, and the owner probably had a high-end gramophone and used fibre or thorn needles. I have never seen a trace of mould on such records - indeed, it always seems to be other records which have slight mildew and it appears as though the wax protects as well as lubricates. But it's impossible to be definitive about this of course, and I might even try the experiment you suggest some time!

[CarlosV]

Shellac discs and cylinders are both susceptible to mold growth but only if kept in humid environments above 50%, hot and humid being the worst combination. Marco, I don't think the application of wax contributes to mold growth: if anything, depending on the chemical composition of the wax it could actually protect the surface as Orchorsol suggests, for instance, mold does not grow on paraphin. The mold that attacks cylinders feast on the soap of which these cylinders are made, they don't have significant amounts of wax in their composition. The main reason I don't wax my discs is the irreversibility of the process - practically it cannot be cleaned off after it sets in the grooves - and for it being a natural trap for contaminants, including the metallic or wood residue that comes off the needles as they wear off during playing.

[Marco Gilardetti]

Do you have an accurate hygrometer in your house, Carlos? I mean a serious one, not one of those that come with bell clocks. You should: you will have a lot of surprises. I do and it's almost constantly over 70%, mostly 80% during winter. In the last summer, during the well known "big heat" across July and August that you certainly remember, it stayed at 90% for 2-3 weeks. The days in which it is around 50% are perhaps 2-3 in a year.

What is commonly intended with "wax" are different compounds:

- bees wax: this is a biological secretion. It is an acid fat with a saponification number of 3 to 5. Being an acid I would not put it over a record, and being a fat it is subject to promote mold growth which enforces what said above. Mold growing is indeed a well known problem in beekeeping, and is counteracted in many ways (that would lead us off-topic here);

- carnauba wax: this is basically an ester of fatty acids, produced from the leaves of a palm. Again I would not put by any means this compound over a record for the same reasons discussed above;

- stearin: this is what most candles are made with and it's a derivative of stearic acid (once again) from processed animal fat (again). It is also a main ingredient of many soaps. A residual quantity of stearin is found on the surface of even newly-pressed records, as it is used as an anti-sticking compound. That's why even brand new 33 RPMs have to be cleaned before being listened to. In few words it's a compound that shall be *removed* from records, not anything that one would want to *add* to.

Finally, I reckon that it is arguable if PURE paraffinum, being a synthetic compound, may or may not protect against mold. I have no personal experience or observation to discuss. Perhaps to some extent yes, in the sense that it would isolate the underlying object from moisture. But I seriously doubt that it may be more efficient than simply keeping the record well clean and with no traces of fat on its surface. And, as you said, it will be nearly impossible to remove, should one change his mind later.

[CarlosV]

- stearin: this is what most candles are made with and it's a derivative of stearic acid (once again) from processed animal fat (again). It is also a main ingredient of many soaps. A residual quantity of stearin is found on the surface of even newly-pressed records, as it is used as an anti-sticking compound. That's why even brand new 33 RPMs have to be cleaned before being listened to. In few words it's a compound that shall be *removed* from records, not anything that one would want to *add* to.

Interesting your mention to stearin, Marco: Edison patented a method to reduce the noise of the diamond discs by applying a layer of stearin. I read they had to apply this process to be able to sell the very noisy discs they were producing during the first War. I have around a thousand of these (the pressed black label ones, very hard to read), but none or very few with any detectable or audible sign of mold. In reality I practically do not have problems with mold in my collection, but as I mentioned, I don't wax records (apart from these DDs that Mr Edison waxed to be able to recoup the loss out of low quality production).

As to humidity, you are right, 50% in my house only during the winter time, with outside temperatures below freezing and inside heaters in full steam. But I wished to have the heat wave you mentioned, here in Luxembourg was about one week above 30C. And that was exceptionally hot!

[Marco Gilardetti]

Hello once again Carlos!

Mold is a very weird beast. You can live your entire life without ever having problems with it, and then all of a sudden it blows! I'm a physicist and not a microbiologist so I simply report my direct experience, that contradicts some points of what is common belief. It is correct to say that humidity is a mold promoter, but it is not correct that in-house humidity is normally below 50%, and also I would not say that high temperatures are needed. On the contrary, the three times that I had serious problems with mold the climate was moderate to cold: spring in two cases and fall in the other. I also believe that other unpredictable factors contribute to mold growth, like for example winds blowing a huge quantity of spores coming from somewhere. I say this because the same climate conditions described above happened other times, but fortunately I didn't notice mold anywhere.

This said, I'm not surprised at all that you have records treated in many ways all of which show no problems with mold. I also never had problems with mold until I had, and please note that in the past I have lived in a basement flat for almost ten years. In those years I even tended to believe that all this talking about mold etc. was all fuss. Then, as said, one day mold knocked at my door. Observing what happened in those days, I think that some facts about mold became very clear in their striking evidence:

1) whichever object is not perfectly *clean* is prone to be attacked by mold: a fingerprint is more than sufficient for mold growth;

2) all fat compounds are an ideal substrate for mold growth: food stains, red oil for furniture, shoes and leather grease, waxes of various kinds (more on this later);

3) some supports, if "greased", are exceptionally prone to develop and promote mold growth: greased leather (belts, shoes, etc), oiled wood and oiled paper, clothes not recently cleaned;

4) chemical reactions driven by molds are very complex and are not restricted to the substrate, but have the power to attack the support as well: leather and paper can be sometimes cleaned perfectly after a mold attack, but other times they are permanently stained in various colours (from red to blue); metals like aluminium are deeply corroded and can no longer be polished, and so on. The same, unfortunately, can happen with shellack: record grooves are deterioretad with visible smudges and audible noises;

5) the more an object is "groovy" or "unpolished", the more easily it will grow up mold: fabric, cardboard, wallpaper, paint on the walls, record grooves (!) and so on. Also unthinkable objects like magnetic tape reels can be attacked by molds.

This said, the worst combination of all has proven to be grease over leather (an almost ideal "biosphere" for molds!) followed by greased wood and greased paper (= old 78 RPMs albums!). The more you steer off from those combinations, the safer you are.

Concerning wax specifically: wax tends to be more inert than grease which in turn tends to be more inert than oil. Also, the more the wax is refined and pure, the more it tends to be inert. For this reason, I would definitely avoid beeswax (which is rarely pure and can contain hundreds of other compounds, from sugars to proteins and so on) but also carnauba wax and stearin which are acid fats (shellack is an alkali) and are rarely available with sufficient purity, the first as it is a food additive (foods have a very low grade of purity) and the second as it is used in very low-tech applications such as stearic candles.

Again, we may question about pure paraffin or other synthetic compounds. Perhaps in the short term and extreme conditions yes: it may indeed have a protective (waterproofing) effect, should an item be stored in a very moist ambient for some time. But I don't really know in the long run and I wouldn't bet a penny. In any case, should it be applied to a record that, still, has to be listened to, it obviously has to be applied in a very thin layer that would be very difficult to be kept clean by other greases like fingerprints; also, being so thin, perhaps the layer would be easily saponified. I don't have a final word on this. Personally, shall I lubrify a record, I would use the purest paraffin available only. But on the other hand I can't really figure any reason why I should really do that.

PS: I get your point, but believe me: you don't really want to have experienced the big heat of this summer!

[CarlosV]

Grazzie Marco for a nice explanation on this hairy subject ...

The scary part is that I am surrounded by greenery, so the spores may raid my home at anytime without warning ! in such case shellac would be the least of my concerns...

Coincidentally I just got last evening a package of discs from the UK, with some 20 or so showing signs of mold, but I picked a couple of samples and they cleaned up neatly with no sound degradation. I add to the cleaning fluid (I use L'Art du Son, which despite the name is German) a product made to disinfect dishes in restaurants, recommended by Uncle Vanya, another member of this forum, to kill spores and prevent regrowth after cleaning.

[Marco Gilardetti]

Yes, that's the quite frequent and "lucky" case: sometimes you just have to wipe off the mold (even with a dry brush) and the support beneath is as new! In an "intermediate" case the support is stained but it is easily recovered (for example: applying some shoe polish to a stained pair of shoes, or washing thoroughly a record). Finally, in the "worse case scenario" the support is deeply damaged, literally corroded, and there's not much left to do than to live with it.

I think that timing is crucial in this respect: if you immediately find out that you have molds in the house and you clean it, the damage is minimal. But if you don't notice it, or when you deal with objects kept for decades in cellars etc., the corrosion is more frequently deep. Of course it also depends on the type of mold, I suppose. We always see a white/greyish fluffy stuff, but there are probably hundreds or thousands of molds, all of which with a different biology and different biochemical properties.

I'm glad your records turned out to be OK. In literature it is often recommended that also the paper sleeves of moldy records are discarded, as quite obviously they are full of spores waiting to be re-activated by moisture. I'll add that records' paper sleeves have been surely touched - over the decades - many times by many hands likely not as clean as they are with today's standards, so they usually fall in the "greased paper" class discussed above. Unfortunately paper is not easy to wash or clean, so the common suggestion is to move it away from records.

I frankly admit that I rarely discard paper sleeves - except when they are an anonymous sleeve "page" ripped of a 78s album: in that case I trash them immediately. When instead they are branded, period sleeves in good conditions, I keep them. They're just too nice to look at and too full of history to be discarded. I try to put the sleeve + record in a dry and safe place if I can, or I accept the risk in all other cases.