Month: September 2019

All models from Thingiverse

A couple of months ago Thingiverse had a phase where users complained every day about the site on this subreddit. People wanted to start new communities with new features but they all came to the same conclusion: Creating a new community from scratch is very hard with the current competitors and no models. That was the point I started a new side project: Download Thingiverse. Round about a month ago I posted my first results I gathered and the public feedback was mixed. Some users had legal concerns and some blamed me for the slow site. The feedback over chat were more promising. I was able to pick out 10 people who helped me spread the actual downloads globally. Thingiverse uses Amazon AWS with a good caching strategy. According to my metrics the downloads had a cache hit ratio of round about 80%. No massive additional load was generated in any way. Thingiverse took no damage from this. Enough technical stuff!With the help from this community I present to you the first Thingiverse dump. What’s inside the box?2088 GByte (2.04 Tbyte) of uncompressed tar files containing 1407580 ZIP files. Each ZIP file represents one thing and contains the files provided by the uploaderA gzip compressed metadata.json file containing additional info: The original Thingiverse ID, author/uploader name, title and licenseA README.md containing more informationsThere are only models included which were published under a copyleft license like Creative Commons or GPL. Use them to start your own community or just keep the files as backup. Check the corresponding thing license for more informations. These files are free from copyright protected material owned by Thingiverse like rendered previews.The files are distributed over BitTorrent. You can get the torrent file here or use this magnet link: magnet:?xt=urn:btih:ac040dc8f9d26bd0bad0592829ddede6355a4ccb&dn=thingiverse-1&tr=https%3A%2F%2Ftracker.hama3.net%3A443%2Fannounce. Please: Make sure that you can also seed the files! BitTorrent itself is not agains the law in most countries! It’s only illegal when you distribute copyright protected files over it like movies. Many linux distributions distribute their ISO files over BitTorrent and you wouldn’t consider it illegal. Please inform yourself if BitTorrent is probibited by your local law or by your ISP.At the end I want to thank all designers publishing their creations under a copyleft license. Please use the files to start your own community. The thing licenses allows you to do that! If you use the files please give a proper attribution. https://ift.tt/2muXJlg

PSA warning about AC linked heated beds

Teaching tech put out a video about using an AC powered silicone bed heater recently. There is a huge glaring issue missing from the video. To use any AC powered device you need to use an SSR (solid state relay) to do the switching. The problem with SSRs is that when they fail, they very often fail in the “on” state, meaning that even when you aren’t sending the signal to allow power, they’re doing it anyway. This means your thermal runaway protection does nothing unless it’s killing power to the whole printer and removing that AC feed. To reiterate, when they fail, they fail in a state that just allows full power 100% of the time to the device they are controlling.There are more cheap knock off dangerous SSRs on the market than good ones. And when you mount them without a heatsink as teaching tech shows, they are very likely to fail. Heat is the enemy of electronics and SSRs need a heatsink for any decent lifespan expectations. There are tons of cheap SSRs that have grossly over rating markings and cheap dangerous internals. A good reliable one is often an order of magnitude more expensive than these cheap ones. On top of that there are a huge number of knock offs labeled as the real deal, FOTEKs are often knockoffs.He also completely ignores proper grounding. Every metal part of the printer should be connected to a real earth ground run back to your wall outlet. If something goes wrong and AC power leaks to the frame it can no joke kill you. The printer should be plugged into a GFCI outlet as well.Please, if you use SSRs with live wall AC on any part of your printer, be safe and have a way for your printer to kill that power should they fail. Live AC power safety is no joke. My experience with them comes from the home brewing world where I’ve built full electric setups and the controllers that use SSRs and AC powered heaters are often quite intricate to make them safe. https://ift.tt/2mh5nQ0