Perhaps then you should start your own thread.
Maybe more people will see it and answer as this thread is about solhaga's AMT.
Maybe more people will see it and answer as this thread is about solhaga's AMT.
I made a membrane out of an emergency blanket by putting the aluminium traces on the PET side of course and using 3M 77 spray as glue instead of the usual 3M 74 film.
Otherwise I used the same methods and tools as before.
The reason for testing the blanket was that I thought it was less noisy and weighed almost the same as the 74 film.
It turned out to look rather cool with the all alu look; the aluminium foils hardly visible.
LF cutoff frequency were higher and HF response ended earlier than my previous membranes:
There were some high distorsion levels despite three glue retainers, but I didn't pursue the matter.
No rescue for the emergency blanket that is
.
I think a better way is to try to make the hinge a little weaker (or softer) on the 74 film membranes. A delicate task
.
Otherwise I used the same methods and tools as before.
The reason for testing the blanket was that I thought it was less noisy and weighed almost the same as the 74 film.
It turned out to look rather cool with the all alu look; the aluminium foils hardly visible.
LF cutoff frequency were higher and HF response ended earlier than my previous membranes:
There were some high distorsion levels despite three glue retainers, but I didn't pursue the matter.
No rescue for the emergency blanket that is
.I think a better way is to try to make the hinge a little weaker (or softer) on the 74 film membranes. A delicate task
.
🙁 to bad, but one has to try 🙂 maybe a PVC or PE foil works, its usually a bit softer and does not make as much noise movements as mylar, but should be possible to get a different thicknesses is gues
Are any of those foils thermosetting? I think for a DIY membrane it is essential that the foil is thermosetting.
Thermoplastic could work, but it would require higher, non-DIY, baking temperatures.
PE does shrink if that's what you mean. Mylar shrinks a bit with heat to, nothing much happening as far as i know in turning in more rigid for instance.
both PVC an PE are thermoplastics with rather low temperatures. well in range of an oven. at least when it starts shrinking. PE is used as wrap for packaging and shrinks. it could help getting everything snug into the folding jig. but i does need some reinforcement just like the PVDC. to hold shape.
most cheap wrap for microwave are PE. then there is the choice HDPE ore LD PE low and high density.
both PVC an PE are thermoplastics with rather low temperatures. well in range of an oven. at least when it starts shrinking. PE is used as wrap for packaging and shrinks. it could help getting everything snug into the folding jig. but i does need some reinforcement just like the PVDC. to hold shape.
most cheap wrap for microwave are PE. then there is the choice HDPE ore LD PE low and high density.
On the 3M tape iTS the adhesive that thermo sets ? Maybe you need to find a foil with same adhesive Or similar. Or find a spray with thermosetting adhesive that might be used on any foil we prefer?
On the other hand we don't want it on the section where the Alu foil is, or it will increase the resonance and adds weight in a section we don't want it.
So a spray is not even a dumb idea , to get thermosetting properties only in the fold/beam.
Maybe with a spray template. Easy to make with a your cutter
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No, it is the PET. From the Wiki:
"Depending on the chemical structure, polyester can be a thermoplastic or thermoset."
It is the film/foil used that is either thermosetting or thermoplastic.
From my post above: "I think for a DIY membrane it is essential that the foil is thermosetting.
Thermoplastic could work, but it would require higher, non-DIY, baking temperatures."
The spray is necessary to get the aluminium foil to adhere to the plastic film used.
The spray is necessary to get the aluminium foil to adhere to the plastic film used.
I don't want it in the fold.
BTW, with beam I mean that the U gets the membrane its rigidness.
That could be a good idea, but for the opposite reason; to only get adhesive where the aluminium foil shall be.
The 3M 77 spray comes off easily though with petroleum ether (white benzene), but one has to be careful not to remove the aluminium foil as well.
To have chalk on the glue residues works better and is safer.
Got some aluminium on mylar from koldby, thank you!
One has to etch in order to get a circuit.
I've tried several techniques but they all failed
.
But I will for sure keep trying.
One has to etch in order to get a circuit.
I've tried several techniques but they all failed
.But I will for sure keep trying.
what kind of foil solhaga ? since i always etch all of mine.
use coppersulfate and salt + water as etchant. works like a charm
and you etch resist wont come of
not sure what you use as etch resist
use coppersulfate and salt + water as etchant. works like a charm
and you etch resist wont come of
not sure what you use as etch resist
for anyone interested in alu foil with adhesive
Aluminiumfolie Zelfklevend | Aluminiumfolie.nl
30 micron and 50 and 100 50 cm wide! eat your heart out 🙂
Aluminiumfolie Zelfklevend | Aluminiumfolie.nl
30 micron and 50 and 100 50 cm wide! eat your heart out 🙂
What about the adhesive:
"Adhesive Transparent synthesis adhesive"
"Temperature resistance From minus 40°Celcius to plus 80°Celcius"
They also got some aluminium on paper.
"Adhesive Transparent synthesis adhesive"
"Temperature resistance From minus 40°Celcius to plus 80°Celcius"
They also got some aluminium on paper.
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yes the adhesive is a bit vague. but 80 degree. i hope your coil wont get to 80 degree to be honest. of course it is possible 🙂
yeah i looked at the paper stuff to, to heavy for my taste. but 18 micron is nice right in between most common foils
I was thinking more if it is used together with thermosetting mylar that sets at 170 °C or more.
ahaaaa. ok yeah did not thought of that since i dont use that method 🙂 well one thing usually is that these sticky glue tends to set again after the temperature drops. and since you bake them in the clamp if i remember correct. that might not be a problem. but ofcourse it better to avoid it at all.
Yes, it might set again.
And there are of course other methods to get the "hinges".
Anyway, it could be good to have one roll of 30 µm aluminium tape and one roll of 18 µm aluminium foil with liner. You'll never know when you need it.
Wrinex, thanks for the tip BTW.
And there are of course other methods to get the "hinges".
Anyway, it could be good to have one roll of 30 µm aluminium tape and one roll of 18 µm aluminium foil with liner. You'll never know when you need it.
Wrinex, thanks for the tip BTW.
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