Go Back   Home > Forums > >
Home Forums Rules Articles diyAudio Store Blogs Gallery Wiki Register Donations FAQ Calendar Search Today's Posts Mark Forums Read

Planars & Exotics ESL's, planars, and alternative technologies

mylar heat treatment under tension
mylar heat treatment under tension
Please consider donating to help us continue to serve you.

Ads on/off / Custom Title / More PMs / More album space / Advanced printing & mass image saving
Reply
 
Thread Tools Search this Thread
Old 28th March 2016, 04:04 PM   #1
malthuse is offline malthuse  Canada
diyAudio Member
 
Join Date: Feb 2016
Default mylar heat treatment under tension

A lot has been written about how quad 'bakes' their panels under tension which locks in the tension and prevents creep over time. I believe that the baking in affect does to the mylar what heating with a heat gun does when repeated to the point that the mylar no longer shrinks. At this point there is no more ability for the material to creep.

I am going to try a method where I stretch the mylar on a regular jig to my required tension. Then I'll heat with a gun to relax the mylar. Retension. Heat. Retension etc.. until the mylar has lost all of it's ability to heat shrink and I'm at my desired tension. I think this might go a long way to stabilizing the mylar over longer periods. Although how I measure that without waiting ten years I don't know.
  Reply With Quote
Old 29th March 2016, 07:25 PM   #2
geraldfryjr is offline geraldfryjr  United States
diyAudio Member
 
Join Date: Feb 2008
Location: Jackson,michigan
That is the basic process of Tensilizing.

This is why it has been suggested to only use Tesilized Mylar, but it seems that it is hard to come by anymore, even when it is stated that the stock you buy is already supposed to be, many have stated that it is not.

The stuff I got way back in the 90's is and I really haven't had any issues with it.

Cheers!!!

jer
  Reply With Quote
Old 29th March 2016, 08:17 PM   #3
malthuse is offline malthuse  Canada
diyAudio Member
 
Join Date: Feb 2016
I didn't realize that was what they meant by tensilized.

I looked up my tensilized mylar and found that it will still shrink 2% with heat which in my mind means it can continue to creep over time. If you mechanically stretch and remove that shrinkage with heat it should be more stable I would think. In any case it can't hurt, unless I end up melting the membrane!
  Reply With Quote
Old 20th October 2017, 04:50 AM   #4
Penguin87 is offline Penguin87  United States
diyAudio Member
 
Join Date: Oct 2009
Hi Malthuse,

Did this process work out? Interested in the results before I start a new project.
  Reply With Quote
Old 20th October 2017, 04:55 AM   #5
malthuse is offline malthuse  Canada
diyAudio Member
 
Join Date: Feb 2016
It did work, it produced stable membranes. I alternated heating and tightening to get to the desired tension. Some trial and error was needed to work out how much heating was needed to completely get rid of the membranes creep.
  Reply With Quote
Old 1st November 2017, 03:10 AM   #6
Penguin87 is offline Penguin87  United States
diyAudio Member
 
Join Date: Oct 2009
Ok, great! Something like 1 min. then wait, stretch, then 1 min.? How many times did you do that process?

Also, was there a problem of even heating, or does reasonable movement across the membrane seem to work out fine?

Thanks so much. I am pumped about this possibility. I know some DIY electrostats that stretched pretty quickly after being built, so this relieves a fear of having that happen.
  Reply With Quote
Old 1st November 2017, 03:57 AM   #7
malthuse is offline malthuse  Canada
diyAudio Member
 
Join Date: Feb 2016
Even heating was an issue. I just manually watched the height and did lots of hot passes. You run the risk of burning the membrane but with some practice you can get it. I think itís better than just stretching as you relief any problems that can occur in the corners with under tensioning.
  Reply With Quote
Old 1st November 2017, 10:09 AM   #8
bentoronto is offline bentoronto  Canada
diyAudio Member
 
Join Date: Jan 2008
Location: Toronto and Delray Beach, FL
mylar heat treatment under tension
My panels are made from Dayton-Wright cells (6 to a side) that are about 45 yrs old. The old ones with the good treble. 30 years in storage in the middle of their life.

Maybe once every two years (except while in storage), I give them a vacuuming and a run with a hair dryer. The dryer I keep in motion, about two inches a second.

I have no idea if it helps in the least or if I am over- or under-heating or why I bother.

Of course, they are working as good as ever, at least to my ears.

Anybody want to comment on the right way to heat or not?

B.
__________________
HiFi aspirations since 1957. Currently working on motional feedback again... the final frontier in audio
  Reply With Quote

Reply


mylar heat treatment under tensionHide this!Advertise here!
Thread Tools Search this Thread
Search this Thread:

Advanced Search

Posting Rules
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is Off

Forum Jump

Similar Threads
Thread Thread Starter Forum Replies Last Post
Diaphragm heat treatment arend-jan Planars & Exotics 41 1st November 2015 07:32 PM
Mylar tension on Sequel II peregrin288 Planars & Exotics 7 15th June 2012 10:18 PM
What do we know about tension of film? joojoo1234 Planars & Exotics 8 1st December 2011 11:31 PM
ESL Mylar stretching Tension Arno Pf Planars & Exotics 2 2nd May 2011 12:28 PM
Tension on chassis eduard Tubes / Valves 35 31st July 2003 01:00 AM


New To Site? Need Help?

All times are GMT. The time now is 03:32 PM.


Search Engine Optimisation provided by DragonByte SEO (Pro) - vBulletin Mods & Addons Copyright © 2017 DragonByte Technologies Ltd.
Resources saved on this page: MySQL 15.79%
vBulletin Optimisation provided by vB Optimise (Pro) - vBulletin Mods & Addons Copyright © 2017 DragonByte Technologies Ltd.
Copyright ©1999-2017 diyAudio
Wiki