Separated capsule with material leaking in front of several filled capsules

The 7 Biggest Mistakes Most Make Getting Started in Capsule Filling

Are you thinking about making your own capsule supplements?

Automatic capsule fillers are durable, efficient machines with the ability to produce a high level of product in a relatively short time, and making the decision to invest in one could be a game changer for your business. When first getting started in filling your own capsules, mistakes may be made. Whether it's with the formulation, empty capsules, or even machine operation and maintenance, running into errors can be a part of the capsule filling process. However, it’s nice to be ahead of the game and be aware of some of those mistakes. Check out the top 7 mistakes businesses have made when getting started filling their own capsules below.


Mistake #1: Using the wrong type of capsule

Imagine this– you get your capsule filler and your empty gelatin capsules, you’ve perfected your formulation mix, and you’re ready to start making those supplements. After the capsules are filled, though, you notice issues such as the capsule breaking due to brittleness, or your filled capsules are fusing together into clumps because they are sticky, ruining your product. Some materials don’t work with gelatin capsules, such as formulations with moisture or hygroscopic materials. 

Because of gelatin capsules’ own moisture content, its composition is affected by any excess moisture in your formulation. Gelatin capsules, when exposed to too much moisture, cause physical changes in the capsule, ruining and wasting your product.

So what happens to gelatin capsules if they lose too much moisture? Ingredients with hygroscopic properties remove moisture from the gelatin capsule. Without moisture, the gelatin capsules become fragile and easy to break, which leads to your product becoming damaged.

A simple fix, rather than going back to square one and changing your entire formula, is to substitute gelatin with hydroxypropyl methylcellulose (HPMC) capsules. HPMC capsules possess low moisture content and can resist damage at low humidities.


Mistake #2: Not knowing the bulk density of your formula

You have plenty of capsules on hand, you turn on the machine, start filling the capsules, and set aside some finished product, and to your dismay, you see that you aren’t achieving the capsule weight that you want. Did you check the bulk density of your formulation?

The bulk density of a formulation is the ratio of the mass of a powder sample and its volume, including the voids in between each particle. This is important to know because the capsule size and desired weight of capsules you want to make are ultimately dictated by the bulk density of your formulation. The table below demonstrates the relationship between capsule size, volume, filling capacity, and density:

Capsule Size Chart

Empty Capsule Size
Capsule Size 000 00E 00 0E 0 1 2 3 4 5
Empty Capsule Weight (Gelatin)
Average Weight (mg) 158 143 123 107 99 78 61 48 38 28
Tolerance ±10 ±10 ±7 ±7 ±6 ±5 ±4 ±3 ±3 ±2
Empty Capsule Weight (Vegetarian)
Average Weight (mg) 163 152 136 107 105 79 63 50 40 30
Tolerance ±10 ±10 ±7 ±7 ±6 ±5 ±4 ±3 ±3 ±2
Empty Capsule Volume Capacity (ml)
Capacity 1.37 1.00 0.90 0.78 0.68 0.48 0.36 0.27 0.20 0.13
Empty Capsule Weight Capacity by Formulation Density (mg)
Formulation Density
0.6 g/ml 822 600 540 468 408 288 216 162 120 78
0.8 g/ml 1096 800 720 624 544 384 288 216 160 104
1.0 g/ml 1370 1000 900 780 680 480 360 270 200 130
1.2 g/ml 1644 1200 1080 936 816 576 432 324 240 156
Empty Capsule Overall Closed Length
mm 26.1 25.3 23.4 23.5 21.6 19.4 17.6 15.7 14.3 11.1
Tolerance (mm) ±0.3 ±0.3 ±0.3 ±0.3 ±0.3 ±0.3 ±0.3 ±0.3 ±0.3 ±0.4
Inches 1.029 0.906 0.921 0.909 0.85 0.764 0.693 0.618 0.563 0.437
Tolerance (inches) ±0.012 ±0.012 ±0.012 ±0.012 ±0.012 ±0.012 ±0.012 ±0.012 ±0.012 ±0.016
Empty Capsule Individual Lengths (cap)
Cap (mm) 12.95 12.95 11.80 11.68 10.85 9.85 8.80 8.00 7.20 6.20
Tolerance (mm) ±0.35 ±0.35 ±0.35 ±0.35 ±0.35 ±0.35 ±0.35 ±0.35 ±0.35 ±0.29
Cap (inches) 0.510 0.510 0.464 0.460 0.427 0.388 0.346 0.315 0.283 0.244
Tolerance (inches) ±0.014 ±0.014 ±0.014 ±0.014 ±0.014 ±0.014 ±0.014 ±0.014 ±0.014 ±0.012
Empty Capsule Individual Lengths (body)
Body (mm) 22.20 22.20 20.22 20.19 18.35 16.40 15.15 13.45 12.10 9.30
Tolerance (mm) ±0.35 ±0.35 ±0.35 ±0.35 ±0.35 ±0.35 ±0.35 ±0.35 ±0.35 ±0.29
Body (inches) 0.879 0.879 0.796 0.795 0.722 0.645 0.596 0.529 0.476 0.366
Tolerance (inches) ±0.014 ±0.014 ±0.014 ±0.014 ±0.014 ±0.014 ±0.014 ±0.014 ±0.014 ±0.012
Empty Capsule External Diameter
Cap (mm) 9.91 8.58 8.56 7.65 7.64 6.96 6.39 5.85 5.33 4.91
Cap (inches) 0.390 0.338 0.337 0.301 0.301 0.274 0.252 0.230 0.210 0.193
Body (mm) 9.55 8.25 8.23 7.36 7.35 6.63 6.12 5.60 5.08 4.68
Body (inches) 0.376 0.322 0.289 0.29
Empty Capsule Quantity Per Case
Capsules per box 50,000 65,000 75,000 90,000 100,000 125,000 175,000 200,000 250,000 350,000

To get started on calculating your formulation’s bulk density, check out LFA Machine’s Bulk Density Calculator. On this page you will have access to a video explaining how to figure out the bulk density of a powder as well as a handy calculator that does all the math for you.


Mistake #3: Formulating material that does not work with your capsule filler’s dosing mechanism

Did you know that you need to tailor your formulation based on what type of capsule filling machine you have? Depending on the type, your formulation needs to have certain characteristics for it to successfully go through the machine and into empty capsules during operation. 

Automatic capsule fillers come with one of two types of dosing mechanisms: one with a dosator and piston and the other with tamping pins and dosing disc. A dosator and piston needs a well lubricated formulation (with an excipient such as magnesium stearate) to aid in ejection by the piston. They also need a formulation that is able to compact so that the capsule plug is able to form and not be broken up. A tamping pin and dosing disc mechanism also requires a formulation to have lubrication and compactibility, as well as good flow characteristics (incorporate dicalcium phosphate in your formulation mix for that) so that the powder in the dosing bowl remains at an even level.


Mistake #4: Storing capsules in the wrong environment

Don’t want your empty capsules to clump up and glue together? Then make sure you store them in the proper environment. Temperature, humidity, and even sun exposure can cause capsules to melt, deform, and/or stick together. Gelatin capsules, in their container, have a moisture content of 13% - 16% . This means that the relative humidity of the environment in which you store your capsules as well as the machine needs to be within the range of 45° to 55°. As far as temperature goes, keep capsules out of direct sunlight and make sure that it’s sitting in the temperature between 64 - 75 °F/18 - 24 °C.

For filled capsule storage, it largely depends on your formulation. But just like with empty capsules, make sure to keep capsules away from windows, direct sunlight and away from any heat/water sources.


Mistake #5: Not getting operator training

Investing in an automatic capsule filler is a big commitment, and not only from a financial standpoint. They are large, heavy machines that take up a lot of space, and their operation involves complicated processes. There’s a chance you might need more support after looking up answers on the internet or following instructions in a manual to successfully get started on running the machine and filling your own capsules. Going in blind to use the machine could end up with your product being wasted, or worse– the machine can be damaged before you can even begin filling capsules.

When you purchase a machine from our FACF capsule filler range, you get 2 days of operator training from LFA Machines. One of our highly skilled technicians will come to your facility and walk you through the ins-and-outs of our fully automatic capsule filler. We’ll show you how to start up the machine, how to successfully operate it, how to make adjustments, and what to do if you run into problems. If needed, our technician can even extend their stay if you have further questions and need more time. Being trained on the automatic capsule machine sets you up for success, ensuring that you get started in filling your own capsules much more quickly and efficiently.


Mistake #6: Not maintaining the machine

Want your automatic capsule filler to have the longest operational life as possible? Then you should establish a regular machine maintenance routine. Committing to consistent lubrication and cleaning schedules is essential in making sure that you’re successful in your capsule filling efforts.

The machine’s filling, dosing, tamping, and ejection stations all have parts that make contact with and move against each other, producing friction. Lubricating the machine’s high traction points reduces wear and tear, making parts less likely to break. Making an effort to apply grease or oil to the machine at recurrent intervals prevents downtime, so you can fill your capsules with no interruption.

Similar to the advantages of following a lubrication schedule, a cleaning schedule can also increase uptime and decrease part repair/replacement. Powder can build up in unexpected places, which interferes with the capsule filler’s components’ movement. This can result in the machine jamming, interrupting operation and potentially damaging the machine. Stopping to inspect the machine after operation and remove all excess debris forestalls changeovers, which will actually end up saving you time and money.

Want to get a better idea of how often to lubricate and clean a capsule filler? Check out our lubrication and cleaning schedules on LFA Machine's product data page.


Mistake #7: Not performing quality checks on filled capsules

It’s easy to assume that your capsules come out consistent and perfect every single time you run the machine. The reality is that there are several variables that go into successfully encapsulating a product, and it might not go smoothly 100% of the time. For that reason, it’s essential that you monitor each run, and that you perform regular quality checks on your filled capsules.

Start the quality check by taking a sample of 10 filled capsules every 15 to 30 minutes (or at a frequency that you think is best depending on your product). Visually inspect the capsules and discard any that have obvious defects such as dents, holes, cracks, or being split; if there are a lot of faulty capsules, stop operation and try to find out what is happening in the machine to cause it. Weigh the capsules from each sample and compare them to see if their fill is consistent. If not, cut off the machine and use the fill adjustment to resolve the issue. 

Being aware of these capsule filling blunders can put your mind at ease when considering whether or not to purchase a capsule filler. If you do run into an issue, don’t worry. Getting a capsule filler from LFA Machines guarantees lifetime support and training– all you need to do is reach out by phone or email and you’ll be back to capsule filling before you know it. 

Contact LFA Machines today to hear more about our machines and services.

© 2022 LFA Machines Oxford LTD. All Rights Reserved.