I make a lot of my own supplements so I thought it would be a good idea to get some Magnesium Stearate to help avoid clumping during powder mixing and powder sticking to my capsule machine. I wasn't aware of the amount necessary in powder blends so on impulse I bought half a kilogram, thinking it would also be used more like a filler and I would burn through it in a year or so. After doing some research, I found that the amount used in tablet manufacture is usually between 1-2 weight percent but I wasn't able to find any info in capsule manufacture. Going off of this information, I decided to experiment a bit and make a 24 count batch of 200mg Caffeine capsules. Note that I am using a "the capsule machine" and marble mortar & pestle.

1. Measured out 10.00g flour, 4.80g Caffeine, 0.22g Magnesium Stearate (~1.5 wt %)

2. Added Caffeine and Magnesium Stearate to the mortar, mixed thoroughly

3. Began adding the flour in geometric dilution, mixing well.

Before I used the Magnesium Stearate I would have clumps of powder stuck all the way up the sides of the mortar and have to scrape it all down. Even with the Magnesium Stearate added, there was still a good amount of sticking. Because of this, I decided to add another 0.22g of Magnesium Stearate to get a 2.8 wt% mixture. After further mixing there was still sticking. I ran this mix through my capsule machine and noticed there was powder sticking to the compression plate.

If anyone has experience with Magnesium Stearate, what weight percent do you use in your powders to avoid these issues? I read that cellulose and corn starch are good fillers. Has anyone here used them with better results?