3D printer filament is typically sold in 1kg/2.2lb spools. The filament is fed from the spool into the printer. The printer melts the filament and then extrudes it according to the pattern.
How long this filament lasts depends on what you print, how often you print, and what kind of printer you have.
That being said, having a general idea of how long the filament will last lets you plan ahead and order more before you run out.
Let’s take a closer look at how long your 1kg spool could last and how to make it last longer!
How Long Will 1KG Last?
Unfortunately, there isn’t really one answer. It depends on a lot of different factors. However, hobbyists can expect to use a 1kg spool in about a month with semi-frequent prints.
Again, you need to take that time frame with a pinch of salt, perhaps even a fist full of salt.
Some printers will go through that 1kg spool in a whole day if they’re printing a large, dense object. Others can stretch it for months if they’re only printing the odd mini.
The only sure-fire way to gauge how long your filament will last is to work out the weight of your objects and add them together.
To get an idea of how much different objects weigh, you should download slicer software. This is the program you will use to create your designs.
Slicer software often has templates and pre-loaded designs. Choose some designs you might want to print and use the provided dimensions and weights to work out how many you can make with 1kg.
To give you a better idea of how long your spool will last, let’s take a closer look at the factors that influence filament use.
How Many Objects Can You Print?
The only firm answer to this question is that you can print any number of objects if their combined weight comes to 1kg.
That’s not a particularly helpful answer though. So, let’s look at some real-life examples to help us visualize 1kg worth of prints.
First up, calibration cubes. Every 3D printer user knows these little test cubes. They’re used to check that your printer and computer are communicating accurately.
These cubes tend to be about 2 inches squared although they can be printed larger or smaller if needed. We’re going to work with the usual 2-inch cube.
With 1kg of filament, you can print around 90 calibration cubes using 100% infill or approximately 335 calibration cubes using 5% infill.
If you’re new to the 3D printing world and a bit confused by terms like infill, take a look further down the article. We explain these factors in a bit more detail later.
Just looking at the number of cubes you can create, you’ll see that 1kg of filament can produce a lot of objects under the right conditions.
Let’s take a more recognizable object, chess pieces. If you print average size chess pieces, where the king measures around 3.75 inches tall, you can get about 400 pieces out of your spool. That’s 12 and a half chess sets!
If you use your printer to create miniatures for model kits or board games, you’re looking at about 100 miniatures. The average miniature takes about 10g of filament. These miniatures are usually about an inch high with a 1-inch round base.
Factors Affecting Filament Use
We’ve already touched on some of the factors that affect filament usage. These include the infill percentage, the extruder flow rate, the size of your prints, and how often you print.
We’re going to dive a little deeper into these factors to understand how they change the efficiency of your printing.
The infill percentage of a printed object refers to how dense the center is. Objects with 0% infill are hollow shells without filament in the center. 100% infills are solid objects.
When you’re planning your print, you can set the infill percentage between 0 and 100%. Commonly, honeycomb designs are used for the lower percentiles. These hexagonal shapes provide some support while keeping the object’s weight down.
If you’re trying to reduce the amount of filament you use, then you should lower the infill percentage.
Depending on the kind of object you’re printing, reducing the infill percentage may not be an option. Objects with low infill percentages are going to be weaker in terms of their structural integrity.
If you need the object to hold weight or support something heavier, you need it to be denser. This will stop the object from being squished or snapping.
The flow rate of your 3D printer refers to the amount of filament that is extruded. Flow rates always start at 100% which is sometimes represented as a decimal as 1.0.
If you want to increase the flow rate, you’re telling the printer to squeeze out more filament. You can increase the flow rate by changing the percentage or the decimal number.
If you want to decrease the flow rate, you’re telling the printer to reduce the amount of filament it extrudes. Again, you do this by changing the percentage or decimal number.
Flow rates have a big impact on the amount of filament you use. You might be tempted to reduce the flow rate to save filament but it’s not that simple. You see, if you reduce the flow rate too much, you’ll get layers that contain holes or missing layers.
In most cases, the flow rate is dictated by the filament you use. Each filament has a different density and different extrusion properties. You’ll need to run some calibration tests to establish the best flow rate for the filament.
You also want to avoid over extrusion which is where the flow rate is too high. When the rate is higher than it should be, you end up with oozing, blobs, and strings of filament. These not only waste filament, but they look terrible on the final object.
You need to test different flow rates to find the optimal level for your filament. This will prevent wastage and keep your printed object looking good.
To find the optimal flow rate you’ll need to print at a variety of different rates. Choose a small model and pick a flow rate.
It’s a good idea to begin your test at 100% first. If you find that 100% results in under extrusion, you can use it as your lower limit.
Next, you need to pick a higher flow rate. For this example, we will say 105%. Again, print the same model and check the outcome. If at 105% the model shows signs of over extrusion, you have found your upper limit.
To hit the sweet spot, you need to test different flow levels between 100% and 105%.
3D printer speeds are measured in mm per hour. Your average home-use 3D printer can do between 30mm and 150mm per hour.
The print speed doesn’t affect the amount of filament you use but it can change how many hours it takes to get through your spool.
For example, a printer with a speed of 100mm is going to be able to print 10 x 10mm objects in an hour. A printer with a speed of 50mm is only going to be able to print 5 x 10mm objects in an hour.
This ultimately means that you’re getting through less filament in the same amount of time. If you’re measuring your filament usage by print hours then the printing speed is a handy metric to have.
However, if you’re interested in working out how many objects you can get out of a spool of filament you don’t really need the print speed.
As hard as you might try, you can’t always avoid failed prints. Sometimes things just go wrong, and you need to start a print again.
Failed prints can cut into your filament usage. The best-case scenario for a failed print is that it happens only a few layers in. That way, you’re not wasting a lot of filament.
Sometimes, unavoidably, a print will fail after hours of printing wasting a good few grams of filament. In those cases, I’m afraid you just have to bite the bullet and bin that chunk of filament.
There are a few things you can do to reduce the chances of your print failing. We’ll discuss these in a later section.
With 3D printers, size matters. Each printer will have a maximum object volume. This figure gives you an upper limit for the size of each object.
The extruder, which is the printing nozzle, moves along a horizontal bar during the print. That bar is connected to vertical supports which move backward and forward according to the pattern.
The horizontal bar can also move vertically along the vertical supports. This tends to happen as layers are added and the printed object becomes taller.
The extruder can only move within the limits of that horizontal bar and the vertical supports. Therefore, it cannot print outside of the cube created by the bar and supports.
An object that is too long for your 3D printer would end up cut off at the limits of the printing area. An object that was too tall would most likely be broken by the extruder at the highest point. This is because the extruder wouldn’t be able to move out of the way of the object.
Larger printers can print larger objects. Larger objects use up more filament. Therefore, bigger printers have the potential to use up filament faster than smaller printers.
It is feasible to use a whole 1kg spool of filament in a single print with the right sized printer, but most people won’t be making prints this big.
Generally, people with larger printers tend to use more filament simply because they can. If you’re concerned about filament usage, try keeping your prints and printer smaller.
Finally, the frequency of your printing is going to impact how long your filament lasts. It’s common sense.
If you print 10g objects every day, you’ll use that 1kg spool in about 14 weeks. If you want the math, here it is:
- 10x7= 70g of filament used per week.
- 1000/70 = 14.2 weeks
If you only print your 10g objects twice a week, then the 1kg spool will last you 50 weeks.
- 10x2 = 20g of filament a week.
- 1000/20 = 50 weeks.
The size of your prints and the frequency go hand in hand. Large prints every day are going to eat up your filament like a hungry hippo. Smaller prints less frequently will barely make a dent.
How to Reduce Filament Use
We’ve touched on a few ways to reduce your filament use in the above sections. However, we’re going to take a much closer look at these methods here.
3D printing isn’t a cheap hobby. It’s always good news if you can reduce the amount of filament used in a print.
Of course, you do need to balance savings with the quality of your print. After all, a poor print is a complete waste of money and filament.
1. Reduce the supporting materials – When you print objects with overhangs, the printer creates supports underneath the overhang. It does this so that it has a base on which to print.
Think about it, if you’re printing a model of a dog, the printer will start by creating the legs layer by layer. When it comes to the belly, the molten filament will need something to rest on until it’s dry.
That’s why the designs create support materials. Support materials are often created out of the same filament as the main model, but they will have a low infill percentage. This makes them much less dense and weaker than the main model. Once the printing has finished you can remove the supporting materials.
If you’re trying to reduce your filament usage, get creative with your support materials. Don’t use thick columns when thinner posts will suffice.
2. Reduce the infill – If you’re trying to reduce your filament usage then you need to reduce the infill percentage. Printing solid objects with 100% infill is going to cost you.
Luckily, very few objects need to be 100% infilled. The hexagonal honeycomb shapes used for lower infill percentiles provide a strong center that is more than adequate for most objects.
3. Reduce failed prints – There are lots of reasons why prints fail. Sometimes it’s because the bed height is off, or the object moves mid-print or sometimes it’s just because.
You can limit the number of failed prints by making sure your printer is set up correctly before each print. Check all your settings and adjustments each time you print and make sure to calibrate properly.
To prevent your object from slipping, you could consider using skirts, rafts, or brims. However, these do use more filament and ultimately end up being discarded.
4. Keep prints small – if the size doesn’t matter for your object, then keep it small. If the object has a function and a predetermined size, then you can’t scale it down. Decorative or display items can be reduced.
The main takeaway here is that your printing habits will determine just how long your 1kg spool of filament will last.
You can take steps to reduce the amount of filament you use in a print but at the end of the day, you’re going to get 1kg of printed objects out of 1kg of filament.