1) What are the various methods that are effective at removing one hundred percent of the conductive coating off from the mylar diaphragm of Martin Logan Monolith III panels?
2) do these removal processes need to be done to both the front and the rear of the diaphragm on the Monolith III ?
I've seen some older discussions on this but I'm wondering if over time the DYI community has developed some better methods. Better as in costs less and lower risk of damage and using stuff that can be found easily at Home Depot or Walmart....and easier to remove one hundred percent of the coating so as to end up with a super clean clear mylar for recoating.
kind thanks,
Eddie
2) do these removal processes need to be done to both the front and the rear of the diaphragm on the Monolith III ?
I've seen some older discussions on this but I'm wondering if over time the DYI community has developed some better methods. Better as in costs less and lower risk of damage and using stuff that can be found easily at Home Depot or Walmart....and easier to remove one hundred percent of the coating so as to end up with a super clean clear mylar for recoating.
kind thanks,
Eddie
well, I'm definitely willing to believe that it is not important to remove one hundred percent. Does everyone here agree that 100% is not so important? Plus, i don't intend to measure it so I would not know whether or not I've reached 80 percent or 97 percent.
But if you had to give a rough estimate, what should be the goal with regards to how much of the original factory coating to remove? I know you're saying that it doesn't matter how much but i'm fully disoriented on this topic so any hint of light would ease my mind here.
I saw an old post that recommended EC-Coating from Martin-Jan. Who is Martin Jan and is that stuff still be best option?
But if you had to give a rough estimate, what should be the goal with regards to how much of the original factory coating to remove? I know you're saying that it doesn't matter how much but i'm fully disoriented on this topic so any hint of light would ease my mind here.
I saw an old post that recommended EC-Coating from Martin-Jan. Who is Martin Jan and is that stuff still be best option?
I makes no difference if you remove all of the old coating and I doubt that you would be able to do so 100%.
Wipe off the diaphragm as best you can with some acetone and/or use denatured alcohol as acetone may cause issues with and dissolve the stator coatings and other plastic if you get it on them.
Alcohol is a better choice!!!
Just make sure that you get them super clean of any oils and NO finger prints as the licron will not stick to these areas at all.
Then mask off all areas were you don't want the licron to get on to as it can cause a leakage Point (bridge) if you don't.
This will cause loss of diaphragm charge(ing) issues.
Then spray the diaphragm so that is has an even wet coat.
Watch for any areas that may pool up and cause dry spots, You can use a foam brush to swab these areas as well, although this may cause a little streaking, Depending on the humidity.
I used a paper towel wetted with the licron and that works as well.
CharlieM has had more experience with this aspect, more than I, with very large panels.
The stuff dries to just a few microns (.001mm) and you may even decide to add another coat just to be sure as it dries extremely clear.
Typically, I have never had to use more than two coat's on any of my smaller panels.
I know the stuff isn't cheap but don't try to use it too sparingly or else you will end up with a coating that has too high of a resistance and may not work as well.
jer
Wipe off the diaphragm as best you can with some acetone and/or use denatured alcohol as acetone may cause issues with and dissolve the stator coatings and other plastic if you get it on them.
Alcohol is a better choice!!!
Just make sure that you get them super clean of any oils and NO finger prints as the licron will not stick to these areas at all.
Then mask off all areas were you don't want the licron to get on to as it can cause a leakage Point (bridge) if you don't.
This will cause loss of diaphragm charge(ing) issues.
Then spray the diaphragm so that is has an even wet coat.
Watch for any areas that may pool up and cause dry spots, You can use a foam brush to swab these areas as well, although this may cause a little streaking, Depending on the humidity.
I used a paper towel wetted with the licron and that works as well.
CharlieM has had more experience with this aspect, more than I, with very large panels.
The stuff dries to just a few microns (.001mm) and you may even decide to add another coat just to be sure as it dries extremely clear.
Typically, I have never had to use more than two coat's on any of my smaller panels.
I know the stuff isn't cheap but don't try to use it too sparingly or else you will end up with a coating that has too high of a resistance and may not work as well.
jer
Last edited:
Freckles On the Diaphragm Martin Logan Coating
We're actually dealing with two different pairs of panels. But I was trying to simplify the discussion.
I have not yet split my Monolith III panels and I may not need to but since we did split the 20 year old SL3 panels we found that after a good wipe down of the SL3 diaphragm using distilled water (with multiple cotton balls) that there were something like hard to noice freckles that seemed to be unafffected by the distilled water. All the surface dirt and black debris was easily removed by the distilled water with cotton balls.
Freckles were a light brown color and they look about the size of human freckles randomly distributed throught the entire diaphragm and randomly sized and shaped, like human freckles on a heavily freckled person.
Freckles look like the factory applied coating might have oxydized in those spots...but I have no way to confirm the cause or nature of the freckles.
We dried the SL3 panels with a cotton hand sized towel. Reassembled and the right speaker sounds as close to brand new as one can expect but the left SL3 is about half the volume or even less than half.
So we don't really know what the correct next step should be but we feel like something has to be done to that left panel. We figured to strip off the factory coating such that the new coating might better integrate with the mylar.
I was thinking these freckles could be spots where the factory applied coating might be ruined somehow.
Kind thanks,
Eddie
We're actually dealing with two different pairs of panels. But I was trying to simplify the discussion.
I have not yet split my Monolith III panels and I may not need to but since we did split the 20 year old SL3 panels we found that after a good wipe down of the SL3 diaphragm using distilled water (with multiple cotton balls) that there were something like hard to noice freckles that seemed to be unafffected by the distilled water. All the surface dirt and black debris was easily removed by the distilled water with cotton balls.
Freckles were a light brown color and they look about the size of human freckles randomly distributed throught the entire diaphragm and randomly sized and shaped, like human freckles on a heavily freckled person.
Freckles look like the factory applied coating might have oxydized in those spots...but I have no way to confirm the cause or nature of the freckles.
We dried the SL3 panels with a cotton hand sized towel. Reassembled and the right speaker sounds as close to brand new as one can expect but the left SL3 is about half the volume or even less than half.
So we don't really know what the correct next step should be but we feel like something has to be done to that left panel. We figured to strip off the factory coating such that the new coating might better integrate with the mylar.
I was thinking these freckles could be spots where the factory applied coating might be ruined somehow.
Kind thanks,
Eddie
is it somehow possible that we caused a "Leakage Point or Bridge" at some point during the process of cleaning them. We split the SL3, wipe down with cotton balls soaked in distilled water, the dried with clean cotton hand towel, then reassemble and play music.
It may be noteworthy that the right panel played dim at first and then after a long while of playing it started to come up to full volumen and is not playing just fine (probably 95% as good as brand new).
The left panel never came up to full volume and remains at roughly half volume. Is that a pssible symptom of Leakage Point or Bridge?
I noticed that when looking closely at some brand new MLs in a store a few years ago. I got the impression that the diaphragm may be multi-layer, with the conductive coating between the layers. The freckles would then be air pockets unintentionally trapped between the layers.
Looking more closely, it looked like there were horizontal "seams" in the diaphragm about 1cm above and below the horizontal spacers. It looked to me like the "extra" layer of film with the conductive coating trapped under it does not extend all the way to the horizontal spacers.
That sort of construction would make sense as it allows you to wipe the diaphragm clean without any danger of removing the conductive coating (unless you actually peel the diaphragm apart with a scalpel).
Well, that's my theory anyway, fwiw. May well be wrong.
Do you also see the "seams"? IIRC, you have to catch the light just right, e.g. looking at a reflection off the diaphragm.
Yes , it is possible that a leakage point my have been created during the cleaning process.
I have read of this happening.
I don't have any experience with the ML's, So I can't help you with any details concerning them.
Only that they are ESL's and they all work on the same principle.
It is possible that the charge ring is not making proper contact as tyu suggested.
I have had similar issues with my own DIY builds of the coating cracking as it is applied before they were tensioned.
This I assume is why ML adds a second coat of a graphite slurry after the diaphragm has been attached.
After washing them it is possible that some of this graphite has been built up in a corner somewhere causing a leakage bridge or something somewhere.
It is typical for them to take sometime to get up to their fullest potential.
The coating has a very very high resistance and can take a while to fully charge.
The best thing is that this shows that there isn't any low resistance paths for them to lose there charge as well.
I used Graphite on my very First builds and it did created such havoc's when it got on parts of the stators and shorted everything out.
Since then I stopped using it and never had an issue since.
Except a few times when using the Original formula Licron as it was a bit Brittle, and, it would crack along the perimeter causing the panel not to charge at all.
Adding a a larger charge ring fixed this issue as I only had one small connection spot.
Also just putting on an extra thicker coat around the perimeter worked as well.
FWIW
jer
I have read of this happening.
I don't have any experience with the ML's, So I can't help you with any details concerning them.
Only that they are ESL's and they all work on the same principle.
It is possible that the charge ring is not making proper contact as tyu suggested.
I have had similar issues with my own DIY builds of the coating cracking as it is applied before they were tensioned.
This I assume is why ML adds a second coat of a graphite slurry after the diaphragm has been attached.
After washing them it is possible that some of this graphite has been built up in a corner somewhere causing a leakage bridge or something somewhere.
It is typical for them to take sometime to get up to their fullest potential.
The coating has a very very high resistance and can take a while to fully charge.
The best thing is that this shows that there isn't any low resistance paths for them to lose there charge as well.
I used Graphite on my very First builds and it did created such havoc's when it got on parts of the stators and shorted everything out.
Since then I stopped using it and never had an issue since.
Except a few times when using the Original formula Licron as it was a bit Brittle, and, it would crack along the perimeter causing the panel not to charge at all.
Adding a a larger charge ring fixed this issue as I only had one small connection spot.
Also just putting on an extra thicker coat around the perimeter worked as well.
FWIW
jer
Last edited:
Yes, I would suspect leakage first before the coating itself. It's WAY too easy to inadvertently create a high resistance path between diaphragm and stator- at high voltage, things that you can't easily see matter a lot.
It's unlikely you'd ever be able to remove the coating, especially with the diaphragm in situ. If indeed that's what's shot, you'll need to replace the diaphragm completely.
It's unlikely you'd ever be able to remove the coating, especially with the diaphragm in situ. If indeed that's what's shot, you'll need to replace the diaphragm completely.
Hi Eddie,
You haven't said why you want to re-coat your diaphragms so I can only assume you suspect the existing coating has deteriorated (reduced output).
I've heard only good things about Martin-Jan's EC-coating but I've not tried it myself.
I have not tried re-coating over a pre-existing coating either, but I have built several sets of large new panels using Licron Crystal ESD in the 8-oz aerosol. It's a bit pricey but easy and fast and after 4+ years of use I hear no degradation at all. Unlike Nylon it's not hygroscopic (no affinity for water), it dries almost completely clear if applied in low humidity (cloudy if not), coating thickness is only 1.5-2.0 microns, it has almost ideal resistivity (E7-E9) for constant charge mode operation, and it sticks very well to PET film (absolutely will not come off if applied to clean PET).
I would not anticipate any problem with cleaning your diaphragms with a simple acetone or alcohol wipe followed by one coat of Licron Crystal applied "just wet". I figure it's good resistivity would be reduced via conduction if applied over a pre-existing coating that was more conductive. Otherwise, I can't see a problem.
Good luck with your speakers!
Charlie
Last edited:
The advertising blurb on my Martin Logan CLS-II from the early 1980s states that the conductive material is embedded in the mylar, not coated on.
My CLS have degraded in performance over the last 30 years to the point that I'm building my own ESLs now, but M-L did recommend washing the panels with water to remove dust and debris that may have built up.
My CLS have degraded in performance over the last 30 years to the point that I'm building my own ESLs now, but M-L did recommend washing the panels with water to remove dust and debris that may have built up.
If it is true that ML's conductive material is NOT coated on and instead embedded into the mylar, then why do the following two things seem to indicate the contrary?
1) in the following video you can see that the mylar is as clear as the air we breathe when they stretch it onto and attach it onto the rear stator. You can also see that they brush on something onto the surface of the mylar.
Part 1: Crafting MartinLogan Electrostatic Panels - YouTube
2) secondly, you will notice that there's a band that runs parallel to the ribs on the panels and this band is clear like the air we breathe because ML does not want conductive material that close to the ribs. Since that band along the ribs lack any conductive material, it further shows that they must not embedd the mylar because of the technique used to stretch and lay the mylar onto the rear stator as seen in the above video.
I'm not convinced that the mylar is embedded. I think someone actually was able to successfully remove the coating and they ended up with a diaphragm that was as clear as the air we breathe.j
I'm 95% sure they don't embedd it.
Below is a quote from this Martin Logan web page:
"The ultra-light, 0.0005-inch-thick polyethylene terathylate (PET) diaphragm is plasma-deposited with a conductive coating in a $20-million, oxygen-free argon environment chamber. This ensures extreme consistency across the diaphragm surface and enables it to accept high voltages without danger of arcing."
And here is a quote from another website stating that ML also wipes the diaphragm with a graphite slurry after stretching:
"Step 4: After being wiped down to remove any oil, dust or foreign particles, a conductive graphite slurry is wiped across the entire panel to fill micro-fractures which occur naturally during the stretching process."
"The ultra-light, 0.0005-inch-thick polyethylene terathylate (PET) diaphragm is plasma-deposited with a conductive coating in a $20-million, oxygen-free argon environment chamber. This ensures extreme consistency across the diaphragm surface and enables it to accept high voltages without danger of arcing."
And here is a quote from another website stating that ML also wipes the diaphragm with a graphite slurry after stretching:
"Step 4: After being wiped down to remove any oil, dust or foreign particles, a conductive graphite slurry is wiped across the entire panel to fill micro-fractures which occur naturally during the stretching process."
Last edited:
If you ever have pulled a pr of ML panels apart.....you can see a silver coat...it embeded.... there not as clear as the air I breathe...i have crub the mylar on 1 panel with grafie... an not the other.....an thay still play....if i feel thay need more coating i clean with water....an add coating over there enbeding....
I have re-work 20 ML panels......the best thing to do with the ML panels is run new Bias feeds up left an right sides..........it only on the right....you well get 3db more output...less is more working on ML mylar....good luck
I'm 99% sure they do embedd it.
I have re-work 20 ML panels......the best thing to do with the ML panels is run new Bias feeds up left an right sides..........it only on the right....you well get 3db more output...less is more working on ML mylar....good luck
I'm 99% sure they do embedd it.
Here's another, telling quote from the same page:
Roughly translated: Don't expect any video or website to reveal the whole process.
I'm still going with my theory that they use a double layer diaphragm with the conductive coating trapped between. Just because the video doesn't show a 2'nd layer of mylar being applied in sections doesn't mean it didn't happen.
"Embedded in the mylar" and "embedded between two layers of mylar" are close enough in meaning.
I recall seeing in one video what looked like the technician applying the bias supply connection, which was just a bare wire end taped down to the surface of the diaphragm. I'm surprised anyone would consider that a durable connection but it implies that the conductive coating is on the surface.
- Status
- This old topic is closed. If you want to reopen this topic, contact a moderator using the "Report Post" button.