I've tried the kapton clone a bit and I have the same observations as you except for that the white spirit as solvent for the silicone glue isn't that effective; the glue doesn't come off that easy. I fear that the aluminium strip will get off as well during the procedure.
I tried to melt the folds with a soldering iron set to 300 °C with little success.
All in all, I feel that it will take a lot of time and experimentation before a membrane based on the kapton clone will be on par with a membrane based on the 3M 74 film.
Maybe it'll do for a low frequency only AMT?
I tried to melt the folds with a soldering iron set to 300 °C with little success.
All in all, I feel that it will take a lot of time and experimentation before a membrane based on the kapton clone will be on par with a membrane based on the 3M 74 film.
Maybe it'll do for a low frequency only AMT?
hmm im not sure if i named the correct, we have terpentine and "wasbenzine" only translation i could find was white spirit (they are both products of oil refinery). the 'wasbenzine' dissolves the glue pretty well here. but there still remains that silicone feeling. but its not sticky anymore. it feels like it could damp very well. its almost soundless on its own. i worried about maybe losing tracks as well. but i did not make a proper laminate yet. i tried a fast one with allot of bubles of course as i could expect. also my way of working is a bit different then yours since i etch the foil. so i first make a laminate then etch, and you first remove the unwanted foil then make the laminate. not sure what would work best with this material. i will make one that is exactly the same as my first tiny panel i think to have a proper comparison and see what happens.
heat setting is indeed hard or not an option at all. i thought about using a paint stripper (heat gun) but you can only use it with one side of the jig removed. so even if it works you will set only half of the folds propper. another option is i believe the way bandsei did add some strips of some sort of tape or paper to keep shape better every serveral centimeters ?
well the proof is in the pudding 🙂 lets build
hmmm i already noticed a problem, the adhesion of the aluminium to the kapton adhesive is not the best... 🙁 i had fes tracks come off in the etching bath. witch result in etching from the backside so its a goner..... might have to clean the aluminium better before adhire the kapton.. give it one more try with laminate i amde this morning. if that does not work im gone make new laminate with a good cleaning step in between. like alcohol
ok sorry indeed the white spirit wont work after all... damned it feels good until its dry an tacky again 🙁, also i having a hard time making a nice laminate even the smallest riplle will become a open circuit in the etching bath.... 🙁 this is getting hard
I did fix the tracks coming off, it is really needed to clean the alumnium foil with alcohol. the ones i did not clean never hold the one i did did hold. so its a needed step!
Nice just to sit down and watch others work. 
Keep up the steam, Wrinex.
I will try to listen to my latest achievements for a while now; haven't been listening to music for a couple of months!
Keep up the steam, Wrinex.
I will try to listen to my latest achievements for a while now; haven't been listening to music for a couple of months!
Nice just to sit down and watch others work.
Keep up the steam, Wrinex.
I will try to listen to my latest achievements for a while now; haven't been listening to music for a couple of months!
must enbjoy the things you make ofcourse.!!
well small update on the laminated making. i use a fram just like you to stick the tape to, it does not ahve to be perfectly without rinkles just sort of the best you can do when only sticket to top and bottom of the frame(you already knew that ofcourse) then i spray a piece of glass with a mixture of water and small amount of soap. i roll out aluminium foil shiny side up on the glass. a few whipes with a piece of cloth to get rid of all the bubbles and you have a mirror flat surface. use soem alcohol to clean the surface of dirt and maybe soap.
i then layout the frame with the kapton on top of it, but because my frame is made of 4mm thick HPL the kapton wont touch the foil yet. i then got a nice rubber roller from the art store(used for adding ground on etch plates) i then start from the middle and only do the right side, then from right/center to the left side . then the other side the same principle work from center then after all is sort of adhered without bubbles you can roll witch ever direction with some more pressure. .
its sooooooo much better its flat as a mirror no bubles nothing its all shiny and perfect. and most of all it wont loseup in the etch. im glad i just did another 8 runs...... its sickening to try and try and try but if the result is good its all worth it after all 🙂 it keeps you going.
next problem.... the tacky surface,,,, in tried soaking it in white spirit. the alu wont come lose but the silicone will swell, and becomes 2 times as thick as the foil itself. but wont come of unless you scrape it. so i guess its a no go to get rid of it. i might give it some flower so it wont be as tacky as it is, or it will be stuck in the folding tool. not really a solution i would hoped for.
That was my conclusion as well, I used the same talkum powder that I use for the glue residue with the 3M 74-film.
although i feel kind of stupid when rubbing it in 🙂 hahah, another optin could be lubricate the tool or something. 🙁 i wish i could remove it all together its not serving any purpose anymore 🙂
smal tiny update... for me its not psible to get the amts out of the folding tool. i tried waxing them i tried powdering the foil. they keep getting a bit stuck.
there are serveral reasons. i believe you have to have slightly smaller folding edge in the tool to compensate for the thickness of the foil. so the folding tool wont bulge and add extra stress on where its folded. its clear when you get the tool apart that the non sticky side of the kapton has far better folds, less sloppy and wide.
second the silicone glue is a **** you can get rid of it you can at best mask it with some powder. but still it remains more sticky then the clean side.
and last but not least 🙂 they do sound rather good when i manage to get anyhting out of the tool.
i now made a comb of HPL with the same spacing of 1 mm that after i remove one side of the tool, can put in with some glue. it makes a pretty solid membrane. this way. and last thing i though about was maybe i can pull at these combs to tension the membrane so you get beter folds over a longer area and deeper pleat. first must find a way to get it out of the tool with both sides looking good.
some fun stuff this amt's one thing Sol is it ok to post my findings here ? or do you rahter have i start a new one. since i kind of have a habit to post ANY findings.. good or bad
there are serveral reasons. i believe you have to have slightly smaller folding edge in the tool to compensate for the thickness of the foil. so the folding tool wont bulge and add extra stress on where its folded. its clear when you get the tool apart that the non sticky side of the kapton has far better folds, less sloppy and wide.
second the silicone glue is a **** you can get rid of it you can at best mask it with some powder. but still it remains more sticky then the clean side.
and last but not least 🙂 they do sound rather good when i manage to get anyhting out of the tool.
i now made a comb of HPL with the same spacing of 1 mm that after i remove one side of the tool, can put in with some glue. it makes a pretty solid membrane. this way. and last thing i though about was maybe i can pull at these combs to tension the membrane so you get beter folds over a longer area and deeper pleat. first must find a way to get it out of the tool with both sides looking good.
some fun stuff this amt's one thing Sol is it ok to post my findings here ? or do you rahter have i start a new one. since i kind of have a habit to post ANY findings.. good or bad
well looks like it, i tried soaping it up before putting into the jig. but still. not the best. maybe that you powder works better? i used ordinary flower🙂 chalk maybe would work beter. measurements i dont have, since im still playing around with what kind of motor what size, and getting the kapton to work with producing anything usefull thats worth measuring 🙂
did some fast measurements ofcourse but just to get an idea of lowest frequency usable etc. even if there is distortion because of failed folding, still gives an idea what you can get if it is gone be a correct version 🙂
how deep are your pleats sol? since you get to 20Khz still but it seem i am getting a huge peak from 11khz to 16khz or so then it falls off yours seem to be pretty straight.
did some fast measurements ofcourse but just to get an idea of lowest frequency usable etc. even if there is distortion because of failed folding, still gives an idea what you can get if it is gone be a correct version 🙂
how deep are your pleats sol? since you get to 20Khz still but it seem i am getting a huge peak from 11khz to 16khz or so then it falls off yours seem to be pretty straight.
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Which part of the flower do you use? Note that some people are allergic to certain flower's pollen.
I always start with measurements. Then I'll do some measurements and on top of that I measure.
Listening to the AMT is the very last thing I do. And then only when a stereo pair has been fitted in the complete loudspeaker setup.
Are you addressing me? Please use the nick solhaga in that case as sol is another user name on this forum.
Do you mean kHz when you write Khz and khz?
Anyway, the folding jig is designed for 6,5 mm deep and 1,6 mm wide pockets. The aluminium foil is 4,5 mm wide so there's theoretically 1 mm of bare mylar on each side of the pocket.
If you are using a dense back pole piece configuration, you'll get reflections from the back wave that will mix with the front wave causing dips and tops in the FR. Consider frequencies with half the wavelength, the wavelength and then multiples of them. Apart from messing up the FR, you are getting an echo effect as well.
One can argue that it is not detectable by ear, but a good measuring equipment capable of displaying waterfall diagrams for these short tume periods for sure will show them.
I am convinced though, that the ramifications of the reflections, apart of the bumpy FR that is, is audible as comb effects etcetera.
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In hindseight, almost all of those that have listened to any of my DIY AMTs have complained about the richness of details and the treble clarity; there are too much of it.
I guess that enjoying the AMT sound is an acquired addiction.
I guess that enjoying the AMT sound is an acquired addiction.
Thx for the reply!
damned flour 🙂 its annoying since FLOUR is as well exactly flower in dutch, and Flower and flour also do sound the same 🙂 i asked myself shall i look it up?.... naaaaa
I guess this is you sense of humor playing up ? 🙂
To be honest i believe we all agreed about witch subject we are talking about and you might be able to find a link, between the correct kHz and even K or khz Khz khZ.
not saying its correct but maybe not even worth noting on a forum like this.
Solhaga or should i say solhaga , its a bit like the Khz kHz. its pretty common to use Solhaga yet again its not your name on the forum 😉 But its oke solhaga ,i will use your proper nickname 🙂 sol sounds a bit stupid to 🙂
well there is no way of removing the reflections completely unless you go bandsei design.
About your 1.5mm width pleats did the pleat width do anything particular in the FR (from 1mm to 1.5 or did you start with 1.5) ? since i used 1mm and Bandsei to i believe, but with 1.5 mm there would be more room for errors
damned flour 🙂 its annoying since FLOUR is as well exactly flower in dutch, and Flower and flour also do sound the same 🙂 i asked myself shall i look it up?.... naaaaa
I guess this is you sense of humor playing up ? 🙂
To be honest i believe we all agreed about witch subject we are talking about and you might be able to find a link, between the correct kHz and even K or khz Khz khZ.
not saying its correct but maybe not even worth noting on a forum like this.
Solhaga or should i say solhaga , its a bit like the Khz kHz. its pretty common to use Solhaga yet again its not your name on the forum 😉 But its oke solhaga ,i will use your proper nickname 🙂 sol sounds a bit stupid to 🙂
well there is no way of removing the reflections completely unless you go bandsei design.
About your 1.5mm width pleats did the pleat width do anything particular in the FR (from 1mm to 1.5 or did you start with 1.5) ? since i used 1mm and Bandsei to i believe, but with 1.5 mm there would be more room for errors
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I look up every word that I am not sure of the spelling as I do for idioms or metaphores.
If it takes me one minute to check it up, I will spare every reader that minute and sometimes much more if there are ambiguities (yes, looked that up).
I'm serious. It takes time for everyone to decode the message if there are ambiguities.
Or having slimmer back pole pieces. Or none but keep them in front.
I have never made any 1 mm pocket width membranes, but I have tested them (got some from båndsei). It was hard to get the LF response I wanted.
So I have never made any myself (as I rembember it!)
Thanks for the reply. well the khz kHz question was just to obvious making a point of something not worth noting but ok. i know i sometimes post messages that almost need an Enigma to decode. and yes that is just annoying. but i also noticed you got a thing for it. so ill try to it keep them in mind. although you are sometimes rather hard in your comments when pointing something like that out.(no offence) 🙂 words in chats or forums and there intention are very easily misunderstood.
soo, got that off my chest.... 🙂 hehe
back to the good stuff
With no backpole wont we run into an uneven field ? i mean its a bit like having a ribbon tweeter with on the left pole piece neo's and on the right ceramics. (ofc not exactly like that)
Without any pole pieces an uneven field in the middle should be less problematic. it is also weird that most commercial amt's have a very high ratio open area versus metal. im curious if this is because of the reflections or just looks good. and if the 1 or 3 bars that are still there do anything for the field. they are usually very thin and narrow
soo, got that off my chest.... 🙂 hehe
back to the good stuff
With no backpole wont we run into an uneven field ? i mean its a bit like having a ribbon tweeter with on the left pole piece neo's and on the right ceramics. (ofc not exactly like that)
Without any pole pieces an uneven field in the middle should be less problematic. it is also weird that most commercial amt's have a very high ratio open area versus metal. im curious if this is because of the reflections or just looks good. and if the 1 or 3 bars that are still there do anything for the field. they are usually very thin and narrow
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