Hey there HBT! I've had my Maelstrom for a few years and it works great. I typically make 3L+ starters using my 5L Erlenmeyer Flask and a 50mm (~2") stir bar. Sometimes I have to fiddle with it to get things spinning without the bar throwing but this not typically a big problem.
But recently I needed to make a 2L starter. I did this in my 5L flask since that's all I had. But I found that the shallower depth of the wort in that 5L flask allowed the vortex to dip down and cause the stir bar to be thrown. No matter what I tried, or how many times, it would always get thrown.
I now have a 3L flask which should prevent this problem since 2L of wort will have more depth in the smaller flask. But, this got me looking into stir bar sizing.
Its hard to find "authoritative" information on the topic of stir bar sizing but I have found info that suggests the stir bar should be "about equal to the magnet size to avoid spinout".
https://www.fishersci.fi/fi/en/scie...gnetic-stirrers/stir-bar-selection-guide.html
I think the Maelstrom comes with a 50mm stir bar if you buy one new today. That's what I have and maybe its the one that came with it. But if I measure from outside to outside of the magnets, its 3" which is ~76mm. However the Maelstrom actually has 2 smaller magnets that are places at opposite ends of a bar that spins. So I'm not sure how to apply this sizing "rule of thumb" in this case.
I have found 76mm stir bars and 70mm that seems more common. Both sizes are more expensive than the much more common 50mm stir bars. I don't mind buying a larger one but also don't want to waste money. So I thought I'd see if anyone on this forum had any insight on this topic.
Should a longer stir bar "hold" better on the Maelstrom or would this be a waste of money?
But recently I needed to make a 2L starter. I did this in my 5L flask since that's all I had. But I found that the shallower depth of the wort in that 5L flask allowed the vortex to dip down and cause the stir bar to be thrown. No matter what I tried, or how many times, it would always get thrown.
I now have a 3L flask which should prevent this problem since 2L of wort will have more depth in the smaller flask. But, this got me looking into stir bar sizing.
Its hard to find "authoritative" information on the topic of stir bar sizing but I have found info that suggests the stir bar should be "about equal to the magnet size to avoid spinout".
https://www.fishersci.fi/fi/en/scie...gnetic-stirrers/stir-bar-selection-guide.html
I think the Maelstrom comes with a 50mm stir bar if you buy one new today. That's what I have and maybe its the one that came with it. But if I measure from outside to outside of the magnets, its 3" which is ~76mm. However the Maelstrom actually has 2 smaller magnets that are places at opposite ends of a bar that spins. So I'm not sure how to apply this sizing "rule of thumb" in this case.
I have found 76mm stir bars and 70mm that seems more common. Both sizes are more expensive than the much more common 50mm stir bars. I don't mind buying a larger one but also don't want to waste money. So I thought I'd see if anyone on this forum had any insight on this topic.
Should a longer stir bar "hold" better on the Maelstrom or would this be a waste of money?