Hi,
it was my impression, that surface tension of the coating fluid decrased when I used foam brushes wiping several times. With the first wipe there were still many streaks, becoming less with every wipe till a consistent fluid layer developed.
Plasma treatment of course is still a way preferable procedure, but so far the appliance of a suitable coating with a foam brush/sponge didn't let me down.
jauu
Calvin
it was my impression, that surface tension of the coating fluid decrased when I used foam brushes wiping several times. With the first wipe there were still many streaks, becoming less with every wipe till a consistent fluid layer developed.
Plasma treatment of course is still a way preferable procedure, but so far the appliance of a suitable coating with a foam brush/sponge didn't let me down.
jauu
Calvin
Experimentally rubbing PET 20 to 30 times with melamine foam at a force between 10N ... 20N will macroscopically slightly blur the surface of the PET.
While coating, one and the same membrane aera may be wiped 2 to 3 times (max.). The applied force (measured!) is in an order between 0.1N ... 0.2N (max.).
So does the the Mylar really get microscopically damaged by using a melamine foam brush for coating? IMO, not very likely. But I think that we both agree that long term results are inherently a question of future outcome*. So for now, there might be no clear answer if there is a risk of damage when resorting to melamine foam applicators for coating, or if there isn't.
For other tastes of potential membrane surface modifications see:
https://www.diyaudio.com/community/threads/membrane-preparation-for-coating.388623/post-7080358
* In accordance to Monty Python's wyse and precise police officer's talk: "If there were fewer robbers, then there wouldn't be wo many. Numerically speaking"
Dear Mr. Dijkstra,
I apologize in advance if this is off topic. Since I'm a relatively new diyAudio user, I'm still unable to PM you directly here and your email address doesn't seem to be working. I'd like to have a quote (with shipping costs) and instructions for your HTEC coating material. I'd like to use it to make a new pair of diaphragms for my Stax SR-007 Mk1 electrostatic headphones, as described in more detail e.g. in my Stax SR-007 diyAudio thread (I asked this in the Headphones section of the forum because I felt it would be more appropriate there). I'd also like to ask you about the longevity of that coating in a scenario such as mine.
The SR-007 drivers have a protective membrane on both sides that keep them sealed and prevent dust from reaching the diaphragm. The Mylar diaphragms are round with 1.4 micron thickness, 87-88 mm diameter and 0.5 mm spacer thickness. The surface resistivity target is about 4 x 10^8 Ohm/square.
Thanks in advance.
Hi
HTEC coating is discontinued. Although I am working on further improvements of this concept it is unlikely it will be offered to DIY. One of the reasons is the limited shelf life of components as well as the finished product itself. This makes it very hard to keep things going on towards the niche market of DIY.
Kind regards
Martin-Jan
HTEC coating is discontinued. Although I am working on further improvements of this concept it is unlikely it will be offered to DIY. One of the reasons is the limited shelf life of components as well as the finished product itself. This makes it very hard to keep things going on towards the niche market of DIY.
Kind regards
Martin-Jan
It all sounds rather silly. While PET ESD safe packaging is aluminum coated, PE bags or PVC tubes seem to be conductive in volume.
Perhaps the need for "The Long Lasting Coating" for PET does not exist: Al does it just fine.
That's said quite a few companies are selling (semi)permanent solutions for PVC/epoxy flooring etc. either acrylic or urethane based, meaning it's no "secret" per say. Most are bluish: the very same component is used.
Perhaps the need for "The Long Lasting Coating" for PET does not exist: Al does it just fine.
That's said quite a few companies are selling (semi)permanent solutions for PVC/epoxy flooring etc. either acrylic or urethane based, meaning it's no "secret" per say. Most are bluish: the very same component is used.
hmm licron crystal should work decently and pretty long if i look at Charlies, ESL. i would opt for the gallon version instead of the spray can, and use a foam brush 
but i did not do tests that where long enough. i had mixed results with the spray can while others had it working for years the one quad uses in the ESL63 works for ever. but is a bit on the low side
but i did not do tests that where long enough. i had mixed results with the spray can while others had it working for years the one quad uses in the ESL63 works for ever. but is a bit on the low side
Original ESL or 63 models and later?
Lots of misinformation about the Quad ESL-63 and later coatings. Always that "graphite coating" talk.
IMHO the graphite layer is not the electrostatic coating.
Aside from what works and lasts, there is the question what coating sounds right and has low distortion.
hmm how is it not the coating. lowest resistance dictates. not saying its great for low end at least its one that remains after 40 years.. the aucoustats, carbon black one works for ever to also not the highest. if there was another coating present. the resistance would be the same as the lowest resistance coating...that would be the graphite coating maybe even a mix with carbon black.
at least its one that remains after 40 years.. the aucoustats, carbon black one works for ever to also not the highest. if there was another coating present. the resistance would be the same as the lowest resistance coating...that would be the graphite coating maybe even a mix with carbon black.
erm but the copper is connected to the top layer. and thats the low ohm coating. mainly by the looks of it,, graphite. you can easily measure from the copper ring to the coating.. and you get the same result as measuring on the foil.. the charge somehow knows where it should sit on the correct coating ? looks to me the ESL:63 uses rather low resistance coating. i dont care really since they work pretty nicely, but could bet better with a slightly higher coating. then again it seems to be a trade of... coatings that vanisch. or something that works for a long time and other stuff screws up. like glue
since they work pretty nicely, but could bet better with a slightly higher coating. then again it seems to be a trade of... coatings that vanisch. or something that works for a long time and other stuff screws up. like glue
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Well i am sure you knew MJ , you where the go to for coatings back in the day !! and mylar i ordered multiple meters of you 6 micron mylar back in the day. (when i was 20 or something... so more then 20 years ago )
i had semi ok results with carbon black, i used a tatoo ink called ..... carbon black or deep black. there are 2 variations one for thick lines having more carbon black. and one for smaller lines having less carbon black... it can be used with acrylics and diluted with water witch screws up the wetting, (surface tension) or alcohol... then again i noticed PU with solvent worked best in wetting, but it wont be able to mix with these carbon blacks. since they are usually water based mixtures to me the PU with a form of carbon black would work great. , carbon black makes it possible to get decent high resistance, and it wont vanish..(or should not, since burning carbon...... gives well carbon) and pu wets mylar really nicely..... well maybe in the future if i try again ill try getting some carbon black powder/nano powder. but getting it suspended in the medium PU nin this case is pretty hard without getting lumps i screwed up quite some blenders trying to haha
i ordered multiple meters of you 6 micron mylar back in the day. (when i was 20 or something... so more then 20 years ago )i had semi ok results with carbon black, i used a tatoo ink called ..... carbon black or deep black. there are 2 variations one for thick lines having more carbon black. and one for smaller lines having less carbon black... it can be used with acrylics and diluted with water witch screws up the wetting, (surface tension) or alcohol... then again i noticed PU with solvent worked best in wetting, but it wont be able to mix with these carbon blacks. since they are usually water based mixtures
to me the PU with a form of carbon black would work great. , carbon black makes it possible to get decent high resistance, and it wont vanish..(or should not, since burning carbon...... gives well carbon) and pu wets mylar really nicely..... well maybe in the future if i try again ill try getting some carbon black powder/nano powder. but getting it suspended in the medium PU nin this case is pretty hard without getting lumps i screwed up quite some blenders trying to haha
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Sure. However polyethylene can be made conductive but I yet to see dissipative (in bulk) PET . That's the point.
Old licron was oxide based. Now it's all PEDOT or other conductive polymer (bluish color).
Same here.
Either Licron or ACL rep told me that aerosol versions are not as good as bottled ones.
Perhaps saturation with gas or low boiling point liquid does not do any good.
There are so many variations of "carbon black" not mentioning «Aqueous Deflocculated Adheson Graphite» varieties.
In order to produce semi-conductive carbon based paint you need flake or needle like particles.
Anyhow one can buy "nanotube" carbon based conductive paint nowadays.
In regard of serial production it would yet another story... as it always was.
It should work expected time like 5 to 10 years or so.
How long should good paint last?
On ever flexing surface?
yeah true, about the life span. then again the quad made it much longer then that. i still have foil here from a quad with a 3000 serial number (that would be late 70- early 80)... still conducts perfectly and nothing came off. so it is possible, to bad the rest of the speaker fell appart
i just ordered some regular coloring carbon black, and some 20nm carbon black... just in case i want to give it another try. but getting it suspended in the medium is the biggest hurdle im afraid
yeah since its flexing a thin layer that does not become britlle might be key i had some PU that is used for sealing concrete that worked pretty nice, its also one component. and can be even more diluted, (it is already very thin) might work, i used it a few times on foil and gives a really nice thin coating. but adding the carbon might be a huge problem. and also spraying it or brushing it makes things clog up, or you can only use the brush ones because of the solvent the foam brush will be done after 10 minutes.. by the way i tend to use those cleaning foam sponges often, the cheap ones are the best in that regard. use the non abrasive side, and cut them foam in a wedge shape. /\ shape and you are good to go
i just ordered some regular coloring carbon black, and some 20nm carbon black... just in case i want to give it another try. but getting it suspended in the medium is the biggest hurdle im afraid
yeah since its flexing a thin layer that does not become britlle might be key
i had some PU that is used for sealing concrete that worked pretty nice, its also one component. and can be even more diluted, (it is already very thin) might work, i used it a few times on foil and gives a really nice thin coating. but adding the carbon might be a huge problem. and also spraying it or brushing it makes things clog up, or you can only use the brush ones because of the solvent the foam brush will be done after 10 minutes.. by the way i tend to use those cleaning foam sponges often, the cheap ones are the best in that regard. use the non abrasive side, and cut them foam in a wedge shape. /\ shape and you are good to go
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Im surprised that there is not a chemist or a materials science person in this sub-forum. I'm neither, but I can figure a few things out.
A few years back I bought a leter of this hoping it would work well, and it did for a while, but slowly increased SR over a couple years. I was mixing it with a water pased polyester resin and a wetting agent for even flow out. IT was quite promising if I could make it more stable.
http://en.hznano.com/product/fjingdian/265.html
Rather than carbon based coatings, you all should look into some of the electro-conductive powders out there.
Sheldon
A few years back I bought a leter of this hoping it would work well, and it did for a while, but slowly increased SR over a couple years. I was mixing it with a water pased polyester resin and a wetting agent for even flow out. IT was quite promising if I could make it more stable.
http://en.hznano.com/product/fjingdian/265.html
Rather than carbon based coatings, you all should look into some of the electro-conductive powders out there.
Sheldon