Brewer's Hardware Stirplate

[jamest22]

I received my new stirplate from Derrin at Brewer's Hardware last week. Since using it twice I thought I would post a little review.

I have used it twice for 2 quart (~2000ml) starters in my 5000ml Erlenmeyer Flask. It works great. The stirplate has plenty of surface area to support the large 5000ml flask securely. I am able to get a vortex all the way to the bottom of the flask without even turning the power all the way up. Very happy with my purchase.

There is only one thing I'd like to improve and its not directly related to the stirplate itself. While the stirplate is running at any speed, there is a rattling noise of the stirbar against the flask. I have tried running the stirplate using different glass containers (measuring cup, mason jar) and no noise is generated. So, I think its just a combination of the bar and my flask. I have seen some people talking about barbell type stirbars that can run quieter in these situations, I'll have to look into those.

 

[Catt22]

I received my new stirplate from Derrin at Brewer's Hardware last week. Since using it twice I thought I would post a little review.

I have used it twice for 2 quart (~2000ml) starters in my 5000ml Erlenmeyer Flask. It works great. The stirplate has plenty of surface area to support the large 5000ml flask securely. I am able to get a vortex all the way to the bottom of the flask without even turning the power all the way up. Very happy with my purchase.

There is only one thing I'd like to improve and its not directly related to the stirplate itself. While the stirplate is running at any speed, there is a rattling noise of the stirbar against the flask. I have tried running the stirplate using different glass containers (measuring cup, mason jar) and no noise is generated. So, I think its just a combination of the bar and my flask. I have seen some people talking about barbell type stirbars that can run quieter in these situations, I'll have to look into those.

The barbell type stir bars require substantially more power than the plain ones. More than likely your stir plate won't have enough torque to spin it. They must also be properly aligned with the fan magnets, which is again unlikely. You could probably remount the magnets with a wider spacing, but then you would still have the torque issue to deal with. A rattling stir bar is usually caused by poor magnet alignment/balance including or spacing. You might try slowing it down. You don't need to generate a deep vortex. A gentle stir works just as well. I use a fairly large 51 mm (2 inch) stir bar and a slow speed. This provides excellent stirring action and zero noise. I have a couple of the barbell stir bars and they also work very well, particularly with a one gallon glass jug. FYI, the barbell type stir bars are rather pricey and I don't see a big advantage to justify the extra cost. What size is the stir bar you are using?

 

[jamest22]

My current stirbar is: 1 5/8" X 5/16"

 

[Catt22]

My current stirbar is: 1 5/8" X 5/16"

There is one thing you could try in order to silence the stir bar. Put two keg dip tube size O-rings on the stir bar. This worked for me when I had the same problem long ago with one of my early attempts at building a DIY stir plate. You may have to experiment some with the O-ring spacing to see what works the best. With mine, evenly spaced about half way to the center on each side worked the best. Most any tight fitting O-rings would work if you don't happen to have the ones we use for the corny keg dip tubes.