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3D print inside out or outside in


Outside In vs. Inside Out 3D Printing? What You Need To Know – Printing It 3D

Trying to decide whether to print inside-out or outside-in can be difficult, especially if you’re printing a very ornate object and want the finished product to be as high-quality as possible. Each option has attractive attributes and things that could potentially cause issues in prints. There’s a clear consensus on which method is better, though.

Printing inside-out provides a more aesthetically and dimensionally accurate result than printing outside-in. Inside-out prints are better because start blobs from nozzles end up inside the object. When printing inside-out, the last layer is undisturbed and naturally has a smoother surface.

In the paragraphs below, I’ll go into more detail about the differences between printing inside-out and outside-in, the uses and benefits of each 3D printing method, the drawbacks and reasons why people avoid each way, and when it’s appropriate to use each technique. As you read, you’ll understand why printing inside-out is better.

Printing Outside-In: The Pros and Cons

Printing outside or printing the outside layer of the print first and then working towards the inner layers is suitable for specific shapes and objects. However, printing this way increases the chances of developing visual faults in your model and is generally not preferred by most users.

So, let’s weigh out the pros and cons of this printing technique and discuss when it is most suitable for a project. 

The Pros

  • It is the best method for printing inward curves. If the object you’re printing has a lot of inward curves, it is okay to print outside-in and print the outer layers first to ensure that all the inward-facing curves on your project are smooth and dimensionally correct.
  • It sometimes results in better support structures. If the exterior surfaces of your object come into contact with your supports, this printing method will strengthen the supports.  

The Cons

  • It often increases the chances of artifacts and flaws on the outer surface of your print. While this printing method is generally more susceptible to start blobs from the nozzles and other visual defects since the first layer is the outside layer. If there are any blobs or adhesion issues on these layers, they will show on the surface of your object.

When To Use Outside-In Printing

Most people are trying to get the highest quality prints possible, which is why this method is so unpopular. It puts the finished product at so much risk for visual flaws by printing the outside layer first and then working towards the center.

The outside-in printing method is only suitable for certain types of surface printing, some overhangs, and, as I said above, printing objects with inward curvature. These are the only situations when it’s better to print outside-in.

Printing Inside-Out: The Pros and Cons

There are many positive things about printing using the inside-out method. Apart from providing the cleanest outside surface level on your prints, it can perform better with overhangs.

Here are the pros and cons of this method, as well as advice on when to use it: 

The Pros

  • The print looks cleaner. Most 3D printer users agree that if you want the highest quality finish on the outside surface of your objects, you will need to print it inside-out. That way, the last layer printed is the outside and stays undisturbed. Printing outside-in is the inverse, exposing the outside surface to much potential damage during the printing process.
  • It reduces the appearance of seam and layer lines. Inside-out printing provides a smooth finish and never has the raised seam you sometimes see on outside-in prints. This seam is created on outside-in objects when the printhead changes layers. An unsightly line like that is not something you’ll ever have to worry about with inside-out printing.
  • The print is usually much more durable.  Inside-out printing can also provide more substantial objects by allowing you to print objects in a way that is more structurally sound. Printing from the inside out makes reinforcing objects and overhangs a lot easier.
  • It results in stronger overhangs. Overhangs are easiest to achieve with low layer height, low print speed, low temperature, and an inside-out print order. Inside-out is the best way to print overhangs since these structures are less likely to droop or curl up when they have interior reinforcement. In addition, they’ll be dimensionally and visually crisp and durable.
  • It’s easier to incorporate some support structures. If you have to add reinforcements to your print to make it more structurally sound, it will be much easier to do so from an inside-out perspective instead of outside-in. That’s because your printer will print the most significant structures first, then radiate out, connecting support structures to the base.  

The Cons

  • It may still produce flaws. You can end up with minor bumps or artifacts in your print from when the print head moves over an area or up to the next layer. These are usually only minor visual imperfections. 

When To Use Inside-Out Printing

If you’re printing many overly ornate objects, you’ll want to print from the inside out to make the entire process easier for yourself. 

Printing inside-out gives you the benefits of more manageable and better overhangs, better outer curvature printing, and smooth final layering. 

Printing inside-out will give you a more durable finished product by making it easier to add reinforcements to your projects. It’s much harder and nearly impossible to add reinforcements when printing from the outside-in.

So, the benefits of printing inside-out heavily outweigh the drawbacks, especially for projects with a lot of minute detail.

Conclusion

If you want your prints to be smooth looking and feeling, structurally sound, and visually ornate with lots of overhangs and different angles and curvatures, then you need to print from the inside out. Creating sturdy overhangs that don’t droop or curl up is also more manageable when printing from the inside out. 

There’s a time and a place for printing outside-in, mostly when printing inward curves, but in any other situation, it’s better to be printing from the inside-out than outside-in.

Can a 3D Printer Be Used in a Hot or Cold Room/Garage? – 3D Printerly

3D printers are great machines that produce lovely models, but one question that people wonder is whether 3D printers can be used in a hot or cold garage, or even outside.

It’s a perfectly valid question, which I will aim to answer in this article so it clears up any things you may have been thinking.

A 3D printer can be used in a hot or cold garage, but it needs to have temperature regulated in some kind of enclosure and some protection against drafts. I wouldn’t recommend putting a 3D printer outside because you can get significant temperature changes too rapidly, resulting in bad quality prints.

There are definitely some 3D printer users out there that 3D print in their garage, so I will give some tips on how to do so, as well as answer further questions surrounding this topic.

Can You 3D Print in a Cold Garage/Room?

Yes, you can 3D print in a cold garage if you take the right precautions such as using a heated enclosure and using build surfaces which don’t fluctuate in temperature too much. A strong power supply also helps with 3D printing in a cold room or garage.

You do have to worry about more factors in order to be able to successfully print in a cold room or garage but it isn’t impossible.

The biggest issue I think you’ll face is the increased level of warping, and prints becoming loose during the printing process before they have the chance to actually finish.

Aluminum is thermally conductive, but it is susceptible to temperature changes by the environment. The best way to overcome this factor is to put a heated enclosure around your 3D printer or some kind of temperature-controlling barrier.

One user who had many problems getting successful prints in a cold room kept having the nozzle knock over the prints and just resulted in many failed models. The room was under 5°C which is very cold compared to a normal room.

Building an enclosure helped tons with this issue.

Some people even opt-in to put a simple cardboard box over their 3D printer to act as an enclosure and retain/control the levels of heat. The worst thing you can do for a 3D printer temperature-wise is to have fluctuating temperatures.

There is also an issue of your actual filament cracking while going from spool to extruder. If you have lower quality filament which has absorbed moisture, it will be more likely to break during the extrusion process.

I’ve written an article behind reasons why PLA gets brittle and snaps which you can check out for more information.

A good thing to have on your 3D printer that is in a cold room is a strong power supply, because your machine will definitely be working hard to keep up with the temperature changes.

A high quality power supply translates to better heating abilities and can really improve your print quality if that is what is holding back your 3D printing.

Printing with ABS in a cold room is definitely going to be difficult, so you’ll have to keep the entire build area at a high enough temperature to stop prints warping. Even PLA requires some kind of heat regulation even though it’s a lower temperature printing material.

It would be a little too expensive to heat up your whole garage constantly.

David Gerwitz from ZDNet found that PLA doesn’t print well at temperatures under 59°F (15°C).

Larger prints are likely to experience layer separation, especially with open 3D printers which are common with FDM style machines.

Can You 3D Print in a Hot Garage/Room?

Yes, you can 3D print in a hot garage or room, but you need to have proper climate control facilities. Being able to control the operating temperature and its fluctuations is an important factor in successfully printing in a hot room.

Depending on your location, your room, shed or garage can get very hot so you need to take that into account when putting your 3D printer there.

Some people decide to put a large-sale cooler or air conditioning in there to regulate the internal temperature. You can even get one with a built-in dehumidifier to absorb that moisture from the air so it doesn’t affect your filament.

It probably wouldn’t be as bad printing ABS in a hot room (may actually be beneficial), but when it comes to lower temperature materials like PLA, they get soft, so they won’t harden as fast.

You’ll need a powerful, efficient cooling fan to get the results you need when printing with PLA. I would probably upgrade your stock fans to something more powerful so each layer can harden enough for the next layer.

If you are 3D printing in a hot room the main changes you’ll want to make are:

  • Decreasing your heated bed temperature
  • Using powerful fans for cooling
  • Regulate your room temperature to be around 70°F (20°C)

There isn’t really a best ambient room temperature for 3D printing, rather a range but the most important factor is temperature stability.

In the hot weather, the electronic PCB and the motors of the 3D printer can start overheating and malfunctioning.

Extreme high temperature may result in parts deforming, whereas cold temperature may cause the warping between print layers.

In the scenario of a resin-based printer, the cooler temperature may affect the print quality of the printer, which may result in a poor quality of prints.

Does 3D Printing Heat Up the Room A Lot?

3D printing does get hot when you are using the heated bed and the nozzle, but it won’t heat up a room a lot. I would say it adds some heat to a room that is already hot, but you wouldn’t see a 3D printer heating up a cold room.

The size, power supply, regular bed and hotend temperature are going to be contributing factors as to whether your 3D printer will heat up a room a lot. It works in the same way as a computer or gaming system.

If you do notice that your room gets hotter when you have your computer on, you can be sure that a large-scale 3D printer will add to that existing heat in your room. A mini 3D printer is a lot less likely to contribute to heat.

To avoid this, you can use low temperature materials and use adhesive substances to get prints to stick rather than using the heated bed element of your 3D printer. A heated bed does reduce warping though so keep that in mind.

You can build an enclosure with ventilation to counter the heat that a 3D printer can create. 

Can You 3D Print Outside?

It is very possible to 3D print outside but you should think about levels of humidity and the lack of climate control. Small changes in humidity and temperature can definitely alter the quality of your prints.

A good idea in this instance would be to enclose your 3D printer in an airtight, heat-regulated cabinet of some sort. Ideally it can block out wind, sunlight, temperature changes and not absorb humidity in the air.

You don’t want any sort of condensation affecting your 3D printer and temperature changes can cause you to hit a dew point which draws condensation. Climate control in this event is very important.

Your electronics would be put at extra risk so it isn’t the safest thing to keep your 3D printer outside somewhere.

There are many hardware parts that have humidity corrosion ratings and other standards. It’s a good idea to get materials that are resistant to humidity such as steel, along with bearings and guide that have the right coatings on them.

A rubber seal is a good idea and having a dehumidifier would help out greatly.

Uncle Jessy did a video 3D printing in the snow, check out the results!

Where Should I Keep My 3D Printer?

You can keep your 3D printer in several places but you should make sure it’s on a flat surface, in a well-ventilated area which doesn’t have sunlight beaming down or drafts to affect temperature. Make sure not to put it on a surface which can easily scratch and to really check the surroundings.

I’ve written an article on this topic about Should I Put My 3D Printer in My Bedroom which goes over these things in more detail.

The main things to make sure of is that temperature levels are consistent and humidity isn’t too high. You also want to store your filament in an airtight container of some sort to prevent it from absorbing moisture in the air.

Without taking care of these things, your print quality can suffer and show many failures in the long-run.

The Best Way to 3D Print in a Garage

3D printer climate control is a crucial parameter to maintain longevity of your 3D printers.

All 3D printers come with a minimum baseline temperature to function properly. Extrusion-type 3D printers have a lower baseline of about 10-degree Celsius.

However, practically no filament would create good quality 3D prints at really low temperatures.

PLA is the simplest filament to perform a print. It can deliver good quality without any noticeable warping or delaminating with temperatures as low as 59 °F (15 °C). At the same time, resin printers are not as sensitive as FDM/FFF 3D printers.

All resins have an excellent print temperature to cure perfectly.

While most resin-based printers nowadays have installed automatic heat control built-in. For better monitoring and performance of the 3D printer enclosure heater or a direct heating mechanism will be your only option to ensure good print quality.

No 3D printer will give high-quality 3D prints at a hot temperature.

Lastly, no 3D printer likes to print when it is too hot. 3D printers ventilate a fair amount of heat on their own, and if temperature comes around 104°F (40 °C) or higher, then the equipment will be overheated without adequate cooling.

Therefore, you need to think about all of these to get perfect 3D prints.

Should I Enclose my 3D Printer?

Yes, you should enclose your 3D printer if you are after the best print quality. Printing with simple materials like PLA doesn’t make a huge difference, but with more advanced, higher temperature materials, it can significantly increase quality and printing success rates.

It’s a good idea to have a cooling system so that you can regulate the operating temperature within the enclosure to fit your desired printing temperature for your 3D printing materials.

Making sure that you have simple and swift access in case anything goes wrong. Another choice is to build a filtration system to filter the air as it escapes the exhaust system. Make sure that the 3D printer parts won’t be affected by direct sunlight.

Attaching an exhaust with a HEPA or Carbon filter to vent out any toxic fumes and UFPs is what some people do to increase safety.

For people struggling with various 3D printing issues, you might want have wanted more guidance towards getting ideal 3D printing results. I created a course that's available to get called Filament Printing 101: Beginner's Guide to Filament Printing that takes you through some of the best 3D printing practices early on, so you can avoid those beginner mistakes.

Cura ruined print. How can I make it print what I see in Blender?

Creality-ender-3 ultimaker-cura 3d design slicing stl

I'm using Cura and it removes my holes, removes print areas and detaches details. In Blender, it looks like it should be, the way I designed it. I know there are a few fails inside (not the manifold), but is there a way to fill everything inside? I only care about outwardly converted faces. This is extremely annoying. I hope someone can tell me how to get Cura to print what was originally seen in .stl.

Here are pictures of what it should look like.

Now these next photos are how Kura looks through them beforehand. Not only does it fill holes (no, hole filling is not included), it adds huge gaps to the side and bottom of the print, as you can see.

How can I get Cura to print what I see in blender in a .stl source file?

I export it to Blender as a .stl file and open it in Cura.

I was able to partially fix this by correcting the normal in Blender, but there is still this:

@TECHSET, ♥3