I bought a Chauvet Hurricane 1301 for its massive smoke output: my aim is to build a low-cost but extremely effective security and anti theft smoke shield and fog bandit clone, by using nothing more than your average disco fog machine… well, at least a renowned powerful fog machine at that. The specs about the consumption are pretty much the same: 1200W nominal power, and about 50W average when turned on to keep the temperature of the liquid constant. What this system lacks, is the “stamina” that professional systems have, since it won’t fill a room with only the first burst of smoke, but it’s not that much delay between the first puff and the second, and you still get the surprise effect. Ideal for not-so-big rooms.
But you may want to use it to spray smoke when certain events happen, like music timed puffs, or pressure plates, you name it.
There is no immediate way to do it: the wired remote doesn’t provide simple short contacts: none of the pins get shorted when you press the “manual” button there, so it must be a powered remote that sends out powered signals.
Solution: catch the short contact given by the manual switch on the machine’s rear panel.
So what about my homemade smoke shield clone system? I just need to find an alarm sensor to wire up to an arduino, to which will be also wired a relay going to the Hurricane 1301.
This is a report of my own experience with trying to obtain 3d-printer-worth filament out of plastic PET bottles.
I was enthusiastic of this video of the russian survivalist The Lawyer Egorov (who by the way has a supercool channel on youtube for you hardcore people):
who built a contraption to get a very strong string (pun not intended) out of scrap plastic bottles. This, I thought, would have been great fodder for my next to be PET filament machine.
Fast forward to yesterday night/this morning. I had been sourcing parts off the local shops and eletronics from foreign sellers on ebay, and in the spare time finally built this revision of my machine:
After I noticed the PET inside the terminal part of the tube was melting, I started the motor, and this is what happened… not much as the pressure inside the tube was low, there wasn’t much material in the column, and since cutting BY HAND the PET string I had was superboring I didn’t really make the small flakes needed for them to be easily transported.
I increased the quantity of PET flakes in the intake, and pressed them down with a screwdriver handle, so the volume of melted mass on the front increased some.
At this point I decided to place the cap with the nozzle drilled in (1.5mm diameter) and in fact some goo started flowing out and quite rapidly solidifying; the quality of this solidified goo appeared “better”, as the surface was very shiny, but it soon stopped flowing out, and when later I unscrewed the cap I realized it was clogged, as a lot of melted material was idling back there and quickly blobbed outside.
So this is the scenario that presented itself when I uncapped the tube:
At this point I decided my adventure with PET had come to an end. Or rather, my experiments did, since I decided since the night before that I wouldn’t be making PET filament for my 3D printer out of plastic bottles: the processing required to this objective it WAY too much. You need to find a way to satisfactorily grind the plastic, after obviously you cleaned the bottles, and after that you should still dry the flakes at 80°+ degrees to avoid water buildup inside which would drasticaly decrease the final product quality. I would totally prefer spending 20€ per roll of cheap black PLA over this.
You also need to take into account the real life scenario, that is, PRINTING with said filament, because that’s the reason you’re doing it, apart from the fact that you’re just a hopeless nerd like me. A printer’s nozzle is SMALL, and nasty things, even if tiny, can clog it; if said nasty things are inside the filament, then no filament filter is going to hep you; they WILL pile up in the nozzle and sooner than later you’ll have to disassemble the nozzle assembly and do nasty things to take it out, like flaming the nozzle to melt the stuff inside and scooping it out with a piece of filament. Don’t trust the cold pull, it didn’t help me when I needed it. Flaming the nozzle instead, it did help me.
Finally, you have to get a decent diameter filament, AND getting that diameter the most constant possible, because if on one side you can change the extrusion rate in your slicing program to take into account the real filament size, on the other there’s nothing you can do to balance a poorly sized filament, and either you will get extruder skipping steps because of a too big filament, or an extruder skipping steps because the filament is too tiny.
In my brightest dreams I supposed I would be producing crystal clear filament out of plastic bottles, heck maybe even multicolored transparent filament since all bottles are slightly coloured.
Final tecnical considerations
By Ian’s own words, with which I agree, the downfall of this method is the feed system: PET can be a great material, yet a DIY extruder like this one does not allow for much leeway, you need to keep the material flowing forward, and for this you need a granulate which can progress easily in the pipe, and at the same time you also need a constant supply in the back.
So, first off, you need to have a ready made supply of flakes, and obviously cannot just improvise by cutting little piece by little piece on the fly like I did (I was desperate to try, I admit it), and even better you need proper sized pellets, not too large but sufficiently thick! Since PET flakes are flat, they easily adjust in the space between the auger bit and the pipe, and they do not progress further very well; also, if you use a string of PET, it will just roll around the auger in one place (where you feed it through) and not progress forward, but instead slowing down and loading heavily the motor by creating a thick wrap on the drill.
You MIGHT melt bottles whole as they are (how?), and use the obtained solidified blob to create smaller pellets, maybe by hammering the glass-like goo. Still, it will take time, and it’s a messy procedure. Unless you can devise a method to do it without much human intervention, it’s going to cost resources anyway, and you may reconsider the whole thing, and maybe just buy pre-made filament, or a commercial extruder plus finding a local supplier of ABS pellets (not your average ebay seller who asks outrageous sums for 3d printing pellets, but a local plastics industry which works with pellets to make for example injection molded items, where you would pay as low as 2€ per kg of granulate).
I had just made a brand new installation of both Ubuntu trusty and vivid and Debian jessie (tried all of them) on my android phone with Linux Deplow, and installed the LAMP stack via SSH. I wanted Apache to serve files decrypted from an EncFS mount, so I found easier to move the DocumentRoot to a subfolder of my home (by editing /etc/apache2/sites-available/000-default.conf – by the way, this file has changed location quite a bit in the past, being called just default.conf, or being httpd.conf in older versions), and changed Apache’s username to my own (by editing /etc/apache2/envvars).
Well, what happened is that, no matter what I did, I was still getting a 403 Permission denied error, which had nothing to do with EncFS.
By pure chance, I went checking what was inside /etc/apache2/apache2.conf, and other than a reference to envvars for the username and group definitions for the user Apache is run as, scrolling further down there are folders definitions which were, in previous versions, located in the default.conf file. Changing in there the reference to /var/www into the new custom folder made it.
You obviously need to restart Apache after such changes.
This is a personal reminder and also an easier-to-find heads up to those looking for a solution: if you installed linux on Android via Linux Deploy, and find that, no matter how you set rules on AFWall+ you can never get internet to the mounted linux image, unless you disable the firewall altogether (not recommendable since you installed a firewall in the first place), then here is the solution provided in this thread (it’s all due to DNS calls being blocked without a possibility to make them pass through in the vanilla AFWall+).
Under AFWall+ contextual menu, open the custom script editor, and inser these lines:
Self reference, and also a heads up for those people looking into listening to 5.1 surround sound in Far Cry 4 and Watchdogs which usually play no sound when Dolby Digital is enabled.
This was tested and works in my configuration using a Sound Blaster USB Surround Pro X-Fi, and doesn’t involve any patch or hack, but a simple linear procedure; the first step is to download the latest drivers from Creative website (may ’14), and then, as the good sir melgu said on steamcommunity:
Open Creative Entertainment Console
Click on the Dolby Digital Live icon
Check the second box (a warning will appear, read it to undestand what it does, then accept clicking Yes)
Open Change Sound Card Settings from Windows Start Menu, and set the entry Speaker (Sound Blaster blahblah) as the default peripheral
This is mainly a self-reference for when I find myself reinstalling Samba on my home server, if something goes wrong and the previous system got corrupt, or if I am upgrading something.
It happens, ALWAYS, that I setup a share with a login, which is the same of the user on the server the share resides into, and when I insert that login info in the Windows dialogue that appears, it just gives me an access denied error, as if the password I inserted wasn’t correct.
What I forget to do, every single time, is to create first a samba user with
sudo smbpasswd -a username
and then using those credentials (which you can create as matching the linux user’s) in the windows dialogue.
I am writing this post also for personal reference (and currently I am writing in bare HTML since my WordPress installation lacks an updated multilanguage plugin to be able to use the WYSIWYG editor).
I was moving my home server from a slow Raspberry PI to a way faster Cubieboard 2, and got to reinstall Transmission daemon. I needed to change its user tho, because I needed a certain folder to be accessible to it.
So I edited as SU the /etc/init.d/transmission-daemon file changing the transmission-debian value into the username I wanted to use, but I kept getting a (warning) message when trying to start the daemon.
Long story short, here are some tips you have to follow, but first credits where they’re due:
This is the page where I got started the first time: http://www.webupd8.org/2009/12/setting-up-transmission-remote-gui-in.html
And this is a heads up I got while trying to solve this problem: https://forum.transmissionbt.com/viewtopic.php?f=2&t=13964
So, back on track:
1) Make sure the transmission daemon is stopped, otherwise changes you make to configuration files will be reverted to original
2) Edit the init.d starting script changing the username to your wanted username
3) chown the default transmission-debian folders to the user you need:
4) If you are importing a settings.json file from a previous installation, make sure to copy it to both /etc/transmission-daemon/ and /var/lib/transmission-daemon/info/ so that both copies are identical
5) You can now start the daemon and everything should work as expected
I work in a relatively safe environment, yet it may very well happen that I need to prove something that someone said in my office, so I can hold it against them when the time comes.
My laptop is always turned on, so I could use it to record the environmental sounds around it, with a couple of requirements:
the recording must be totally unattended, starting when I turn on the pc, and stopping when I turn it off, without any user intervention
the recorded files must be somehow purged, starting from the oldest ones, so that my disk doesn’t get filled with audio files
As in the Ubuntu spirit, I tried to search for something that did the job right away, but with no luck.
So, still in the Ubunt spirit, I had to arrange it myself: the idea is to record the audio in chunks of 10 minutes, and each time delete the oldest files, so that there is a chosen number of max files inside the recording folder.
You will need the audio-recorder package for the job, install it as follows:
when the program is installed, open it (Alt-F2 and then launch audio-recorder), click on the “additional settings” button, and setup your default recording folder there, in this example it’s the folder “audiofiles” directly under your home folder.
Also I suggest changing the file naming standard to %Y-%m-%d-%H:%M:%S so that each recording can be easily associated with the time of starting.
Then, you need to make a bash script that will deal with starting a new recording, while closing the previous one, this is what I came up with:
which does exactly the following: stops a previously open (if existing) instance of the program, and starts a new one, then deletes the oldest recorded audio chunks so that there are maximum 150 files inside the recording folder (if you want a different amount, just replace 150 with the number you prefer); please note that the recording folder written in this bash script must be the same that is set in the additional settings, so if you want to use a different folder make sure to set it up both in audio-recorder and in this bash script.
Also, please note that the username part of the path must be replaced with your ubuntu username.
You can create this bash script as a “recordaudio.sh” file in your home folder, and then be sure to chmod +x recordaudio.sh so you can execute it.
Then, you need something that actually starts the recording, and cron is our friend here.
Run the command
and if it’s the first time you run it, you should be presented with a choice screen asking you which editor you prefer… absolutely choose nano!
Inside the editor screen, paste this:
*/10 * * * * /home/username/recordaudio.sh
where “username” must be replaced with you ubuntu username, then press Ctrl-X to save the file (press Y is prompted to confirm).
What this cron line does, is running the bash script we just created every ten minutes, so the recorded sound files will be 10 minutes long. If you want to change this length, just change the 10 in the command to the number of minutes you prefer.
Restart the pc, and notice how files are being created inside of your folder. After a while, you will also get over the set limit for the files, and you will notice how the number of files will always stay the same, with the oldest files being deleted.