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News The Project Technology RoboSpatium Contribute Subject index Download Responses Games Gadgets Contact <<< Imprint ...to be continued. >>> General thoughts about 3D printersWords about benchmarking and specsI know, for you it's all about specs and benchmarks which was my way of thinking, too before I got a hand on a couple of devices. Benchmark prints are less than half of the truth about a machine, because there are so many different printer designs that all have their pros and cons and one or two or three prints can't check for the weak point that might be an issue for your special needs. A printer can shine in one benchmark and fail in another one, simply by changing the filament used or just because the environmental temperature is different than before. Only a few people (and none I know in person) have a workshop with climate control and you won't like to buy a ton of filament at once just to ensure all your plastics is from the same batch. Have a look at test prints to see if the printer of your choice gives an output that makes it useful for your projects in general, but don't over-interpret the details.The first printers I got were the Tronxy P802 and the Anet A8. Both come as kits and the specs as well as the construction are nearly identically. They are at the low end of the price range by what the mechanics isn't very sturdy. From a professional view, those machines are "toys", however there is nothing better to learn about a subject than playing around with the technology behind. There is a large community around those printers and with 3D printed addons you can improve the quality of the devices step by step. That's the way I like it! One thing that separates toys from tools is the build quality. If you want to do prints, prints, prints, you should look for a sturdy machine that comes assembled, which makes them more costly than the cheapest kits. A solid frame, metal bearings and all the electronics in a metal housing are key elements of the better machines. Layer height and resolutionThe layer height of your 3D printer is nothing but a value stored in software. 50 microns layer height sounds 4 times better than 200 microns and a 0.2mm nozzle enables you to print more details than a 0.4mm nozzle. Yes, but:With a 0.05mm layer height your print needs four times longer to finish than with 0.2mm layer height. Same is with the nozzle diameter and so with the extrusion width - you'll need double the print time with a 0.2mm nozzle than with a 0.4mm nozzle (assuming constant layer height). So if for you it's all about specs, you must do prints with 0.05mm layer height and a 0.2mm nozzle to get all the details your machine offers. That means four times the print time compared to a 0.4mm nozzle and 0.2mm layer height. Large prints can take half a day and more to finish and do you really like to wait two days and more for a print to finish? The longer a print needs to finish, the more likely something will go wrong. The chance for clogging is higher with a small diameter nozzle. A layer height of 0.2mm is what filament printers can handle reliably and that's what I am using for my projects with a 0.4mm nozzle. You won't get sub millimeter structures from your CAD model printed perfectly with a filament printer, even if the specs of your device might imply that! You'll always notice the rough surface of 3D printed parts, no matter if they were manufactured with 0.05mm or 0.2mm layer height - you must accept that and even with that, it works fine for prototyping parts! Print volumeI know, you'd like to have a machine that can print an Airbus A380 in one piece, but you should forget about that. Small is beautiful!The smaller a machine, the more easy it is to make it a sturdy one. The levers are short and so backlash is a minor issue - at least in theory. Think small if you are looking for a first 3D printer. Those devices are cheaper in general and so you'll save money for your next printer - if you stay with 3D printing, you will always have an eye on your next machine with better specs, no matter how expensive your first one was... Another issue that grows with growing dimensions is warping, that occurs due to material shrinkage while printing. Large parts will more likely loosen from the build plate while printing than small parts do. Prints with a base area of 20 times 20cm cause real trouble if you ever tried. Think of printing objects with a 10x10x10cm build volume rather than 30x30x30cm if you want to have real fun with your 3D printer. However, having a large build area enables you to print multiple small parts in one run which might be comfortable if you do lots of printing and you are short in time. By CAD software you can split large construction elements into smaller ones. In doing so, your rate of success will be higer and you'll become a better designer with each new project. Where to buyYou can buy cheap at one of the Chinese online stores. Buying cheap means buying with almost no support, because that's what raises costs. I got my machines from Gearbest for free, but no: I did not get hand selected machines from better quality because even that kind of "support" isn't included...However the good thing with those stores is that you get working 3D printers for really cheap, they don't take your money and run away. If you buy in a store in your country, the same machine is clearly more expensive, just because service and warranty aren't for free. 3D printers are no mass production devices like normal printers, which is why tehy are made by small companies and so service in general (no matter where you buy) isn't what you expect from large companies, especially if you buy in the sub 1000,-€ section. Another good news is that you get cheap spare parts for your cheap printer. You can replace the mainboard, a stepper driver board or a print head if you have learned how a 3D printer works and buying a cheap printer lowers the hurdle of doing experiments with that machine and so become an expert step by step. I am glad to have access to non perfect but cheap Chinese stores - they help to democratize technology (somehow). It's up to you where to buy your device - I am not the shoulder to cry on if your transaction went somehow wrong, however I will try to help whenever you run into trouble with the technology of your 3D printer. ConclusionThe really good thing is: All the printers listed here can do the magic of materialization of your ideas.The one machine that beats them all doesn't exist. 3D printing means studying how things work, readjusting parameters and doing a job again and again until you get a working result. Having a 3D printer means entering the fascinating world of rapid prototyping with all the risks of failures included. If you just want to print beautiful sculptures copied from various sources on the web, well buying a bunch of plastics figures is much cheaper than buying a 3D printer... Reviewed 3D printersMy personal recommendations:
Technical data
Special offers from my sponsors as well as my personal ranking of the tested 3D printers are available in the column shopping tips. 
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