3D Printing Tips and Links

This is a list of tips and links about 3D printing in general. There will be some specific to the Creality Ender 3 and the Monoprice Mini Delta because I own both of those printers and have some bit of experience with them. I will talk about general 3D printing and related topics also.

NOTE: This is a work in progress. It may appear jumbled and there is no doubt duplication. Hang in there while I work through getting the stuff populated.


Section Links


Disclaimer and Explanation

ALL of what is said here is subject to my own opinion and bias. Use your own brain to decide if you want to follow any of it or ignore it. No warranty of any kind applies to what I say here and you are totally responsible for your own actions. I believe that everything I'm saying here is factual. Sometimes I will add a disclaimer about something. That's a clue that you should research the topic elsewhere too.

I have made mistakes in my 3D printing adventures. Nothing destructive but sometimes things just don't work the way I expected. My biggest one so far has been reassembling the hot end for the Mini Delta incorrectly. I had plastic oozing out all over the place and it was a major rework to get things back the way they should be. It took almost two weeks to get parts and do the work to get things straight. It won't happen again because I learned from my mistake.

My motives for the way I'm involved in 3D printing are probably different from most people. I'm a technology geek from very early in my life and a 45+ year computer geek. I love to tinker with things both electronic and mechanical. I also love to tackle and solve problems. That's the engineer in me. I have a degree in Electrical Engineering which I never really used as such because I became involved in computers (mainframe) right out of college.

I'm retired so mostly my time is my own. Unfortunately my finances aren't as extensive as I would like so I'm also very frugal. I'm an amateur radio licensee (AK8B) and I do get involved with activities of the local radio club. I'm also involved with model railroading with a local club. There is lots of opportunity for 3D printing there.

So you see that I'm kind of a unique character. I'm not afraid to dig in and solve the problem and 3D printing certainly presents a whole new set of those problems to keep my mind exercised.

If any of this helps you out I have accomplished something. I had no intention of doing anything like this rambling series of pages when I started out in 3D printing. As I went on I realized that I had acquired a huge wealth of information and experience that I felt I should share.

If you find something incorrect or that you need some clarification on feel free to contact me here.


General Introduction

You may have heard that 3D printing is hard to figure out. I won't try to change that perception because it can be. It will NOT be easy but it doesn't have to be hard. It will be challenging. If you like a challenge then keep reading.

The internet is your friend for finding guidance. There is a LOT of information out there about 3D printing. Some of it is really good. Some of it was good 5 years ago but has become obsolete now. This is something you will need to look out for - how old is the information.

I will be posting links and ideas grouped into the sections shown above. If you're new here then just work your way down the list. If you're coming back to look at a particular area then you can use the section links to find what you're looking for.

Have a look around and I hope you will enjoy the experience.


How Traditional Part Manufacturing Works

There are a few traditional ways things are manufactured:

  • By subtractive forming. Think of using a lathe or mill to take away the part of a block of raw material to make the part you need.
  • By molding. Molten plastic or metal is put into a mold that determines the shape of the part you want.
  • By forming. A 'blank' of material is shaped into something more useful. Think of a blacksmith forming a horseshoe from a bar of iron.
These methods make up the overwhelming majority of how things are manufactured.


How 3D Printing Works

3D printing is an ADDITIVE process. You start with nothing and add plastic in an organized manner to produce a part. How does a 3D printer do that? It does this by squirting plastic out of a tiny nozzle that moves around left, right, forward, and back over and over as the nozzle is raised a tiny distance up from the base for each layer.

As you might guess this can take some time. The typical nozzle hole is 0.4 mm (that's 1/64 of an inch for you non-metric readers). That means it has to make 25 passes side-by-side to get the the width of 1 centimeter (or 63 to get about an inch).

For layers the thickness can vary quite a bit. For most of my prints on the Ender 3 I use a 0.16 mm layer height meaning I need about 64 layers to get 1 centimeter.

A 5 centimeter tall (that's 2 inches - this is the last time I will put in a conversion) simple figurine takes 1-2 hours to print.


The Realities of 3D Printing

3D printing is not a cure-all for every problem. It's not a solution for even a small number of problems. It is a solution that YOU can use directly without interference. You can let your imagination and creativity flow freely.

3D printing is SLOW. Don't expect anything useful to print in under an hour and expect several hours for anything sized bigger than a golf ball.

It's not just printing time either. It is true that there are millions of freely available 3D models including almost anything you can imagine but if you can't find what you need you will have to design it yourself. Do you know how? If not you will have to learn. Even after you learn how to design your part it will take time (hours probably) to actually design it.

After you have your 3D model you must process it through a slicer to convert the 3D model into the gcode instructions that your printer needs. This isn't hard but there is a learning curve involved. There are many options to tweak in the slicer software and learning how they will influence the finished product. Don't be too worried about this though - many have gone before you and survived the ordeal.

3D printing is NOT well suited to manufacturing. Because of the long time and setup effort it's just not an economical way to make lots of anything. If you want one or a few then it may be the right way to go. It is ideal for prototyping parts to make sure they will fit and function. It also allows a company to keep their prototyping secret by keeping the development completely in-house.


Printer Safety

3D printers are dangerous machines. They are intended to be operated by responsible humans and are not suitable as toys to be operated by unsupervised children. It's not likely to kill a child but can certainly inflict serious injury to them. Yes, you too can be injured so BE CAREFUL!

Some of the hazards are obvious - that hot nozzle can burn you really badly. Third degree burns are a real possibility. You can of course also get your fingers in the wrong place when something is moving and get crushed. There is no forgiveness or safety clutches in these mechanisms - the stepper motors WILL move things where they are intended to go no matter what is in the way.

And don't forget pets. A cat will surely try to probe at the moving hot end and either be burned or ignited. Yes, the nozzle gets hot enough to set your cat's fur on fire. Alternatively, the cat may get it's paw caught in the mechanism and decide to jump off the desk and drag your printer to the floor. Not a good scenario.

There have been reports of 3D printers catching fire. There are safety features built into the latest versions of the Marlin firmware that is generally used but manufacturers continue to produce their printers with older versions with these safety features TURNED OFF! There are solutions for this but it involves you updating the firmware and turning on the safety features.

The bottom line here is to NEVER leave your printer unattended for any period of time. I'm always in the house and awake whenever there is a print running. I tend to check on any print at least once an hour. I also have a smoke alarm and a fire extinguisher in the room with the printer.

Also be aware that the Bowden tube is made of PTFE - Polytetrafluoroethylene which is better known as Teflon. When PTFE gets too hot (above 260C) it starts giving off noxious and dangerous gasses. An all metal hot end will get the PTFE tube away from the really high temperatures of the hot end. It's one good reason to do that upgrade if it's possible.

Ventilation can be important for some filaments like ABS which gives off noxious fumes. It's one of the reasons I won't be using ABS.

As the '3D Printing Professor' (see YouTube) says - "Safety First!".


Where Do 3D Printers Come From?

At Christmas time, Santa brings them. Other times they are delivered by the printer stork - or UPS.

You knew that wasn't real but it sounded cool. The reality is: from countries all over the world.

As you would probably expect the less expensive ones are coming from China. Chinese products do have some reputation for being less then stellar but that is not necessarily deserved in the 3D printer market. Yes, there is some outright junk out there. There are also some pretty good printers to be had. The Chinese do tend to cut corners and this results in a less than perfect product. Most have learned to NOT cut corners where it really counts. It's usually minor stuff - like a Bowden tube connector that you can easily and inexpensively replace ($7 for 10 from a US address). It's nothing more than a minor annoyance.

Speaking from experience with Creality (the Ender 3) I can say that they make a pretty good product with some minor shortcuts taken (like that Bowden tube connector). In general, they have put together a really good line of printers with a large range of capabilities. I would certainly buy a printer from them again.

No matter where the printer is manufactured the parts to put it together are going to come from all over. This is a worldwide market and every manufacturer has to pick and choose the parts available wherever they can find them to assemble their product.


The Metric System

EVERYTHING about 3D printing is in metric. Get used to it. The world outside of the United States has years ago. You should NOT be converting between systems either. There is no need. Once you get the feel for lengths you will just naturally use metric lengths just like you use inches. It's just a matter of getting a feel for how big a centimeter is.

Temperature is another matter. The good thing is you don't really need to know that much - just that everything that counts will be HOT and you shouldn't touch it. The nozzle will be dangerously hot - typically 210C (410F - nasty hot). Bed temperature will probably be around 50C (122F - also uncomfortably hot).

The only time you will need to know about temperature is when things are cooling down - what level is safe. I consider 30C (86F) a safe level for both the nozzle and bed to cool down to before I turn things off and shut down for the day.


      


Choosing a Printer