Erlenmeyer flask and stir plate question / Help!!

[Castle Meadow Brewery]

I just picked up one of these and I'm having trouble using it w/ my stir plate. Does your flask have small depression in the bottom or is the bottom of your flask flat. I'm in the trial and error stage getting my stir plate to work and I'm having trouble. I've seen all types magnet configurations bur still can't get it.

 

[FlyGuy]

Mine is flat on the bottom.

Did you try starting really slow and then center the spinning stir bar before cranking up the speed?? Not sure from your message what the problem might be.

 

[homebrewer_99]

If you have a 3rd magnet try holding your flask over the stirplate with the magnet clinging to the stir-bar.

Center the stir-bar and pull the magnet straight down. That should keep the stir-bar in the middle of the flask.

Now lower the flask on to the stir plate.

 

[Castle Meadow Brewery]

The bottom of my flask is concaved for stability so the stir bar gets thrown before it even gets started. My magnet (from a hard drive) is centered on the fan but I think Im going to get a few more, move them to the outside and stack them. Hopefully that will work.

 

[homebrewer_99]

If it gets thrown as you set it down it sounds like you need an ON/OFF switch more...