Beginner Guide

From Roaddog Labs Docs

The Roaddog Beginner Guide to building a 3D printer.

This guide is to help lessen or shorten your learning curve if you are a first time 3D printer builder. This guide focuses on building a Reprap style 3D printer. The guide is for the kits we sell the information and tips are relevant for most any DIY or Reprap style printer build. It's not meant to be an exhaustive resource in and of itself. There is too much good information out there for any one place to be the only source. Using this guide along with our build docs and links to other information will well compliment learning how to build and use a 3D printer.

Choosing a machine

Often the most difficult part is deciding which machine to build. There are many great choices for every budget and skill level. This guide assumes you've made your choice (which is why you are here) but I'll offer some thoughts anyway. Pick something you can afford and build as you go. Being able to afford it may seem obvious but be wary of starting without knowing what it will cost in the end. Many start by buying parts as they can afford them. That's a great way to build a machine, get a bit at a time. It's not uncommon for people to take six months or better to save up enough to finish the machine. If you are doing that try to plan your build in such a way that you'll be able to build as you go, instead of waiting until the end. For example, get the frame, rods, bearings and hardware first. That way you can start the mechanical aspect of the build and be able to work on it while you save the money for the more expensive parts. Particularly the electronics and hot end.

Be mindful of your budget but don't skimp. Hot ends are one place where people try to save some money. it's the worst place to try and do that. The hot end can make or break your build. You can work around some other issues but if you can't control the extrusion of the plastic, it's game over. There are a lot of good choices, get something others are pleased using.

For first time builders I suggest one of the variants based on the Prusa i3, specfically the Rework version. It's well documented and prices are pretty affordable. It's got an ample build envelope for a first time builder and isn't difficult to assemble or configure. If your budget or space is cramped have a look at the Smartrap. It's a good build for a limited budget or if you have a small footprint. At this point it's not as common as an i3 variant but if your wallet is a bit light it could be a good choice for you.

There is a temptation as a maker to make the biggest, best you can afford and perhaps modify it along the way. I suggest building your first machine as per the build docs. After you've tested it and know how to operate and get good prints from it, move to the bigger machine or those mods. With the knowledge (and confidence) of a first successful build with some good prints under your belt you'll go a long way toward modifying your first machine and incorporating changes to suit your particular situation. Make sure you've got a good base build and the mods will come after that.

Here is a comparison of the two kits we recommend that make excellent entry level builds.


You'll need a small work area with plenty of light and comfortable seating. Some try to build on the bed in their dorm room but you'll have an easier time sitting at a workbench, desk or small table. A small card table and folding chair will work.


You'll need a small assortment of hand tools. It's not too much but there might be a few things you may not already have. The tools don't have to be the most precise or expensive tools and there are many good sources for low cost tools suitable to build a DIY 3D printer. In the US Harbor Freight Tools is a good, low cost tool store. In Canada Princess Auto is a similar store.

For most builds you'll need the following...

Set of small sized metric hex keys. A ball end is preferable. You can use T handle hex keys but there will be some cases where having the 90* short side will be advantageous. The most likely sizes are 2.5 mm, 3 mm and 4 mm depending on your kit but you'll need a few other sizes as well. I suggest getting a key set with individual keys instead of a key set that is contained in a holder. This is one tool you will use quite a bit in not only your build but in using and maintaining your machine. Get as good a quality as you can afford.

A small adjustable open end wrench or two. Most kits that use rod frames use nuts that require between 10 mm and 14 mm wrenches. You can use combination or open end wrenches but for most a simple adjustable open end wrench (sometimes called a "crescent" wrench) is all you'll need. For small nuts, for example the M3 nuts, having a small wrench that is sized for those is handy but you can do the same with a small crescent wrench.

Some small screw drivers. At least one each of a jeweler's size slotted and Phillips head as well as a medium size of each head.

A hobby knife (also known as an "Xacto" knife) with fresh blades or some other kind of utility style cutting knife. It will need to be sharp enough and stiff enough to cut plastic yet small enough to get the blade into some areas. An art supply store will have these individually as well as in a kit with a variety of blades and handles.

Small round file. At least one small round file (3 mm or 1/8") and one small flat file. It's best to get a set, you can pick up an inexpensive set at most tool or hardware stores.

Pliers. A set of small diagonal side cutting pliers (also called wire cutters) as well as a set of small needle nose pliers.

Small torpedo level and tape measure or ruler. A small combination square works as well. You need to be able to measure up to about a foot (300 mm) and make sure things are level and square. Having a level, square frame is key to consistent results from your machine.

Some other tools that are good to have but not necessarily a must have..

A digital volt meter. You can get one at Adafruit or Sparkfun that will do the job. It needs to be able to read both AC and DC voltage, resistance/continuity at least and having more advanced functions like a diode checker or DC current is good to. Unless you are troubleshooting circuit boards you'll only need to measure voltage or resistance/continuity.

A larger assortment of the basic tools listed above.

A magnifying desk lamp on a swing arm. Especially for us old guys...

A soldering iron. Many kits come with the wiring pre assembled but there will be cases where you'll need to repair your machine and need to solder something. Unless you are into electronics you don't need a full blown desktop soldering station. A direct powered iron will do. For any of the electronics tools Sparkfun or Adafruit are good bets. Of course you'll need solder and some solder wick for when you need to take the solder off.

If you really get into it a small vise and a device called helping hands (alligator clips on a stand to help hold wire) are good to have but at this point they are a luxury.

A small heat gun for shrinking tubing or softening parts. Sometimes you'll need to soften parts to get things to press fit in to a part, for example a bearing. Lightly heating it is a good way to do that. You can also use a household hand held hair dryer.

Approaching your build

Once you've got an idea of what you want, have the tools and space and have parts coming in it's time to start organizing how you are going to do your build. Can you do it all in one shot, over a long weekend? Will you need to spend only an hour or two at a time, a few days a week until you are done? Effectively managing your expectations will go a long way toward a build that is not only informative but enjoyable and satisfying as well. The build is only the beginning of the journey. It's possible to build an entry level Reprap in a long day but I don't advise it for a first build. Remember, this is supposed to be fun so if you get tired or frustrated take a break and come back to your build later.

Before you start count all your parts. Make sure you have what you need in parts, supplies and tools. Nothing worse than getting into a build on a Saturday then finding you need something just after the store closed. Or worse yet, not having everything and needing to get it shipped in. Check your vendor's counts against those in whatever build docs you may be using. If you aren't sure ask your vendor or one of the online communities.

One of the hurdles in building a DIY machine is the lack of standard documentation or conflicting documentation even for what appears to be the same machine. If you are buying kitted parts or a complete kit your vendor should either be able to point you to the community/project docs or have docs that outline the build. They should also be able to point you to the source files for the machine you are building. Know what your vendor will and won't support. Many vendors offer great service and help with a build. Many though, do not. Even if your vendor does offer build support there may be times where they can't give you a personal tutorial on your build. Perhaps they are out of town or otherwise not available after business hours. That's where building a machine that has a wide online community comes into play. There is likely going to be someone there that has experienced that same problem. And there is likely someone that also is interested in the answer. They may be stuck at the same place as you or someplace similar. When you get advice and it works it's good practice to followup online and let everyone know what did or didn't work. That helps create a large base of knowledge which is more effective than any one single monolithic information source.

If you've made it this far, you're ready to build...