DIY 3D printers
www.reprappro.com (closed the business since beginning 2016)
http://www.makerbot.com/
http://printrbot.com/
http://www.hyrel3d.com/
DIY and 3D printing communities and social networks
3D models search engines
http://www.yeggi.com/ Main 3d model search engine
http://stlfinder.com/ STLFinder .stl search engine
http://www.3dpartsource.com/ Finding industrial parts based on your 3d models, still in Beta?
http://3dbility.com/ (not working anymore)
http://3dshap.es/ Searching 3d models on the web based on the 3d model you upload, still in Beta
http://yobi3d.com/ Yobi3D search engine
http://www.fabforall.com/home (not working anymore)
http://stlfinder.com/ STLFinder .stl search engine
http://www.3dpartsource.com/ Finding industrial parts based on your 3d models, still in Beta?
http://3dbility.com/ (not working anymore)
http://3dshap.es/ Searching 3d models on the web based on the 3d model you upload, still in Beta
http://yobi3d.com/ Yobi3D search engine
http://www.fabforall.com/home (not working anymore)
3D model and printing services marketplace
http://3dlt.com/
http://www.kraftwurx.com/dfretail (users can open their own shop)
https://www.3dagogo.com/ (They test 3d models to give reliable 3d prints)
http://www.3dprintwise.com/
http://en.cults3d.com/
https://www.threeding.com/
https://www.mixeelabs.com/ (custom toys, figurines etc.)
http://www.pinshape.com/
http://3dvix.com/
http://sandboxr.com/
http://wip.mxd3d.com/ (they bought and integrated makerpicks.com, 3Dhippy.com and http://www.maker6.com/ Maker6, finding 3d printers, 3d model sharing and marketplace)
http://kazzata.com/ Marketplace for 3d printable spare parts
http://www.solidry.com/ Solidry is 3d model and 3d printing marketplace focused on India
https://www.meltwerk.com/en/index.php MeltWerk
http://www.cgtrader.com/ CGTrader is a place where you can sell and buy 3D models
https://www.make-it-3d.com/
http://www.trinpy.com/ Spotify for 3d models? what?
https://www.3yourmind.com/ Compare 3D printing services in real time and choose from over 150 high quality materials and finishes. Order your 3D printed model online in just a few simple steps
https://www.3dprintler.com/ Compare 3D-printing prices for 254 materials across today's biggest 3D-printing services and order instantly!
Connecting people who want to 3D print to the people owning the machines
http://cowfab.com/
http://www.makexyz.com/
https://www.fabhub.io/ (more then just 3d printers, various other CNC and digital fabrication machines)
http://www.fabgate.co/en (get quotes and choose best one)
http://fabbery.com/ (including other machines like CNC etc.)
http://3dpinpoint.me/
http://www.100kgarages.com/ Big maker community with many different sorts of machines
Marketplace that connects aspiring product designers with top 3D modelers
3D model repositories and Thingiverse alternatives
http://www.fabfabbers.com (looks like its off-line)
http://www.rascomras.com/ (in Spanish)
http://www.cadyou.com/ (open source community for 2d and 3d models) (looks like its off-line)
http://leopoly.com/ (Creation and sharing of 3d models)
http://www.bld3r.com/ (They say they are 3d printing social network, models are from various sites)
http://www.freebie3d.com/ (looks like its off-line)
http://cadigo.com/ (looks like its off-line)
http://treasure.is/
http://www.3dvia.com/
https://cubehero.com/
http://nasa3d.arc.nasa.gov/ official NASA 3d model resources (spacecraft and other space objects)
http://3dprint.nih.gov/ NIH 3D Print Exchange for publicly available biomedical files. It has many 3d models of molecules, cells, viruses, bacteria, medical content, scientific lab equipment etc.
http://www.librarylyna.com/ Collection of high quality educational 3D models to foster learning of the blind and visually impaired.
http://www.spyder3dworld.com/
http://www.stlhive.com/ STL Hive is focused on RC projects and robotics
http://morphosource.org/ Very large repository of fossils 3d models
http://b2b.partcommunity.com/community/
http://www.traceparts.com/
https://www.3dcontentcentral.com/
http://www.bibliocad.com/
https://github.com/nasa/NASA-3D-Resources NASA GitHUb repositora of 3d models and 3d printing related objects
https://3axis.co/ laser cutting
Sharing and embedding 3D models
http://dotdotty.com/ Cloud Platform for Viewing, Presenting and Sharing all of your 3D Models.
https://sketchfab.com/
Discover, compare and troubleshoot 3D printers
http://senvol.com/database/ Senvol database with industrial 3d printing machines and materials, searchable by various parameters
http://www.aniwaa.com/ Compares 3d printers, scanners, materials and other machines,
Company that makes 3d printers for usage in space:
http://www.madeinspace.us/
Manual wiki on how to calibrate RepRap based 3d printers (useful for other types also):
http://www.reprap.org/wiki/Calibration
Manual wiki on how to troubleshoot RepRap based 3d printers (useful for other types also):
http://www.reprap.org/wiki/Print_Troubleshooting_Pictorial_Guide
https://www.simplify3d.com/support/print-quality-troubleshooting/ Simplify3D visual guide on troubleshooting common 3d printing problems
Flickr group with 3d print failures, problems, causes and solutions
http://www.flickr.com/groups/3d-print-failures/
Uploading and sharing of 3d models.
http://viewshape.com/
CAD files and collaboration tools:
http://grabcad.com/
http://www.turbosquid.com/
3D printing, additive manufacturing, CAD/ CAM jobs resources:
http://3dprinting.com/jobs/ 3D Printing job board from all over the world, site is in English
http://www.3ecruit.eu/ Recruitment agency spcialised in 3d printing and digital manufactuirn human resources
https://3dprintedjobs.com/
http://www.3dprintingjobs.biz/ (not working anymore)
http://gravity3drecruitment.com/ 3d printing talent recruitment agency (not working anymore)
Various 3D printing blogs, forums and sites
http://3dprintedinthe.us/ A Discord buddy from LBRY.io server
http://chopmeister.blogspot.com/ (fellow Croatian blogger Chopmeister and 3d printing developer famous for DD1, H3 and other accessories)
https://letsprint3d.net/ Guides and posts for 3d printing noobs. New blog on the scene.
http://www.bld3r.com/
http://www.3dhacker.com/
https://sites.google.com/site/3dprinterlist/home
http://graphics.stanford.edu/data/3Dscanrep/
http://ei8htohms.tinyparts.net/
http://forum.conceptforge.org/ (For anyone that is or is considering building GUS Simpson, LISA Simpson, and/or Wally 3d printers by Nicholas Seward, you should check out this build forum.)
http://richrap.blogspot.com/
http://nothinglabs.blogspot.com/
http://go3dprinting.tumblr.com/
http://directory.3dprintingindustry.com/ Most extensive directory of 3d printing industry related sites.
http://reprap.development-tracker.info/ RepRap Development Tracker (hardware and software)
http://mtm.cba.mit.edu/ The Machine that make project at the MIT Center for Bits and Atoms seeks to develop low-cost machines that can be made using CNC equipment.
http://www.mold3d.com/ Mold3d - 3d printing resources for artists
http://reprapmagazine.com/ Very good free magazine about 3d printing
http://open3dlp.blogspot.com/
http://static.wikifactory.org/
http://www.buildyourownsla.com/forum/ Forum dedicated to building of DIY SLA 3d printers
http://www.tridimake.com/ 3D printer improvements, tutorials, software OpenSCAD etc.
3dprinting.com I wrote for them for some time.
http://community.3dprintingclub.net/ Forum and community site
http://edutechwiki.unige.ch/en/3D_printing 3d printing wiki, slightly outdated and not maintained often
http://personalfactory.tumblr.com/ Tumblr blog / news aggregator run by Lukasz Wardzinski
http://www.3dprinterprices.net/
http://multiphysics-cae.blogspot.hr/2016/06/3d-printer-mechanism-simulation.html
http://www.tridimake.com/2016/06/3d-printing-nozzles-characteristics.html Great post about nozzle specifications and types
http://www.universeofdesign.com/
YouTube 3D Printing Channels:
Joel Telling (3D Printing Nerd) https://www.youtube.com/channel/UC_7aK9PpYTqt08ERh1MewlQ
https://www.youtube.com/user/TheMakersMuse
https://www.youtube.com/user/ThomasSanladerer
https://www.youtube.com/user/thang010146/videos Huge and updated collection of mechanical motions, mechanisms and systems animated in a simple way
3D printer build guides:
http://reprapbook.appspot.com/ (Detailed guide how to build older RepRap Prusa Mendel printer)
http://reprap.org/wiki/The_incomplete_reprap_beginner%27s_guide
3D Scanners
http://www.david-3d.com/ (free DIY laser 3d scanner, paid premium version)
http://www.matterform.net/
http://cubify.com/sense/ (3D Systems Sense 3d scanner)
http://www.volumental.com/ Volumental cloud based 3d scanner, works with Kinect camera
http://robocular.com/ Robocular 3d scanner
http://www.freelss.org/ FreeLSS open source laser 3d scanner with fully 3d printable structure and RaspberryPi electronics and uses the official Raspberry Pi 5MP camera for sensor.
Sardauscan is very low cost 3d scanner, can be made gor under 30 USD. http://diy3dprinting.blogspot.com/2015/03/sardauscan-is-cheapest-diy-3d-scanner.html
Forum for DIY and entry level 3d scanners: http://www.diy3dscan.com/
http://www.trim3nsion.de/ Full body twister 3d scanner
DIY laser engravers / cutters
axCut DIY laser cutter https://github.com/Axford/axCut
http://redmine.laoslaser.org/projects/laos/wiki
http://usuaris.tinet.cat/sje/cnc/laser_eng.htm
http://www.hpi.uni-potsdam.de/baudisch/projects/constructable.html (laser pointer guided laser cutter)
What materials can you safely cut and engrave with a laser cutter and possible results:
http://atxhackerspace.org/wiki/Laser_Cutter_Materials
http://obrary.com/collections/open-designs A collection of free designs for laser cutters and some free manuals
http://3dpburner.blogspot.com/ 3dpBurner is an open source laser cutter/engraver CNC machine with NDB7875 laser module.
http://www.thingiverse.com/thing:1780556 FABOOL Laser Mini is an open-source, ready-to-assemble type of desktop laser cutter and engraver.
http://robots-everywhere.com/re_wiki/pub/web/Main.LCheapo.html LCheapo laser
http://www.scorchworks.com/K40whisperer/k40whisperer.html K40 Whisperer advanced software for Chinese K40 type laser cutters/engravers
DIY CNC machines
http://diylilcnc.org
http://www.cnc4everyone.com/
http://lcamtuf.coredump.cx/gcnc/full/ Tutorial for CNC machining, mold making and resin casting. A sort of CNC for dummies. Guide developed for robot builders, model makers, and other hobbyists by Michal Zalewski.
http://www.instructables.com/lesson/Welcome-to-CNC/ Free CNC educational course on Instructables
http://www.maslowcnc.com/ large area Maslow DIY CNC for 350USD
3D printable fashion
http://threeformfashion.com/
http://3dshoes.com/
Open Source software and hardware
http://diy3dprinting.blogspot.com/2013/11/open-source-hardware-1.html (First OSHW related post on this blog with video compilation introducing the topic of open source hardware)
http://opencircuits.com/Main_Page (Open Circuits is a wiki for sharing open source electronics knowledge, schematics, board layouts, PCB prototype, ports and parts libraries.)
http://www.openbuilds.com/ Community with sharing of various DIY machines projects (3d printers, cnc, robots etc.)
http://www.openbuilds.com/ Community with sharing of various DIY machines projects (3d printers, cnc, robots etc.)
Industrial high end 3D printing companies
3D Systems http://www.3Dsystems.com
Stratasys http://www.stratasys.com
Arcam http://www.arcam.com
ExOne http://exone.com
Voxeljet http://www.voxeljet.de/en/
Organovo http://www.organovo.com
EnvisionTEC http://envisiontec.com
EOS http://www.eos.info/en
Concept Laser http://www.concept-laser.de/
SLM Solutions http://www.slm-solutions.com
Optomec http://www.optomec.com
Asiga https://www.asiga.com
Dassault Systemes http://www.3ds.com
Groupe Gorge (Prodways) http://prodways.com/en
http://www.windform.it/ Advanced materials for additive manufacturing
http://www.uzata.com/ Marketplace for used commercial and industrial 3d printers
3D printing food
http://www.naturalmachines.com/
http://botbq.org/ open source BBQ extruder
http://www.bocusini.com/
http://www.fabacademy.org/
https://www.coursera.org/course/design
https://sites.google.com/site/mostlyharmlessarms/
http://www.3dprint.toys/ (not working anymore) Marketplace and repository for 3d printable toys
http://fosscar.faikvm.com/trac/ Project that wants to create open source aluminum 3d printable car parts
http://www.homemadetools.net/ Frequently updated site dedicated to all sorts of DIY tools
http://my3dmatter.com/influence-infill-layer-height-pattern/ great post with experiments and measuring the influence of infill percentage, layer height and infill pattern on final object qualities
http://www.3dbenchy.com/ Calibration website that features model for calibration and how to measure the outcome. Very good resource for calibration and optimizing your machine.
http://www.3dprintnerd.com/ List your 3d printer or other products and services for free
http://botbq.org/ open source BBQ extruder
http://www.bocusini.com/
BioPrinters, Medical 3d printers adn 3D printing organs
3D printing and DIY education
http://www.fabacademy.org/
https://www.coursera.org/course/design
3D printed toys
Various 3d printing and digital fabrication sites
http://www.coultersmithing.com/forums/index.php Crazy DIY forum, not for everyone ... stay safe kids
http://fosscar.faikvm.com/trac/ Project that wants to create open source aluminum 3d printable car parts
http://www.homemadetools.net/ Frequently updated site dedicated to all sorts of DIY tools
http://my3dmatter.com/influence-infill-layer-height-pattern/ great post with experiments and measuring the influence of infill percentage, layer height and infill pattern on final object qualities
http://www.3dbenchy.com/ Calibration website that features model for calibration and how to measure the outcome. Very good resource for calibration and optimizing your machine.
http://www.3dprintnerd.com/ List your 3d printer or other products and services for free