HBT 2015 Big Giveaway - Winners Drawn - 24 Hours to Claim!

Huge Supporting Membership Discounts - 20% Off - Ends Today!

Home Brew Forums > Home Brewing Beer > DIY Projects > Chillers and Stir Plates > My Stirplate does not work properly
Reply
 
Thread Tools
Old 04-24-2013, 07:31 AM   #1
Majd
Feedback Score: 0 reviews
Recipes 
 
Join Date: Jun 2012
Location: Santa Clarita, California
Posts: 87
Liked 2 Times on 2 Posts
Likes Given: 2

Default My Stirplate does not work properly

I did build a new stirplate using a good quality potentiometer and a motor that is mounted on a metal plate that is mounted on 4 screws that are setting through the bottom of the box (see the picture). I mounted two earth magnets on a plastic disk that is mounted on the rotating axle. The distance between the two earth magnets is equal to the length of the stir bar that Im using, 1. Al spins fine with slight wobbling, but in all it spins fast and slow and it does fine without water. However, when I put water in the flask, the bar will spin fine at slow speeds but when I increase speed (slowly or fast) the bar spins out to the side of the flask. The best I could get is a start of a vortex. I even have put two earth magnets at each end which did help little bet but not good enough. Any thoughts?

Cheers
Click image for larger version

Name:	Stir plate.jpg
Views:	290
Size:	35.5 KB
ID:	117634  
Majd is offline
 
Reply With Quote
Old 04-24-2013, 09:51 AM   #2
cooldood
Feedback Score: 0 reviews
Recipes 
 
Join Date: Jan 2013
Location: Belgrade, Maine
Posts: 569
Liked 121 Times on 93 Posts
Likes Given: 39

Default

do not use stir magnets with the hub in the middle. This allows it to wobble until it finally spins off to one side. If you have one of those magnets put a small o ring on each end and it will be fixed.

see my thread

http://www.homebrewtalk.com/f51/stir...magnet-404859/
cooldood is offline
 
Reply With Quote
Old 04-24-2013, 10:08 AM   #3
JohnK93
HBT_SUPPORTER.png
Feedback Score: 1 reviews
Recipes 
 
Join Date: Oct 2012
Location: Danbury, CT
Posts: 325
Liked 16 Times on 14 Posts
Likes Given: 4

Default

Have you tried playing with the position of your flask relative to the magnets? Mine has to be off-center or the bar will spin off...something to do with the slight dome in the bottom of the flask.
__________________
JK Brewing
@ibrewmyownbeer
ibrewmyownbeer.com
Primary: Oktoberfest
Secondary: Empty
Kegged: English Ordinary Bitter, A Whiter Shade of Pale Ale IV
Up Next: ??
JohnK93 is offline
 
Reply With Quote
Old 04-24-2013, 12:53 PM   #4
unclevername
Feedback Score: 0 reviews
Recipes 
 
Join Date: Apr 2013
Location: Palm Harbor, Florida
Posts: 35
Liked 6 Times on 5 Posts
Likes Given: 3

Default

I had the same problem with similar sized rare earth magnets. So I tore open a hard drive and put the hard drive magnet on top of the existing magnets and problem solved. It has not thrown the rod one time since I did this. Attachment is easy because the origional magnets hold the hard drive magnet in place.
unclevername is offline
 
Reply With Quote
Old 04-24-2013, 08:43 PM   #5
Majd
Feedback Score: 0 reviews
Recipes 
 
Join Date: Jun 2012
Location: Santa Clarita, California
Posts: 87
Liked 2 Times on 2 Posts
Likes Given: 2

Default

Quite genius fix, I like it particularly because I have two of those computer disk magnets available. I just want to know how did you position those crescent shapes over the earth magnets? Do you have a picture or a diagram?

Thanks
Majd is offline
 
Reply With Quote
Old 04-25-2013, 12:54 AM   #6
unclevername
Feedback Score: 0 reviews
Recipes 
 
Join Date: Apr 2013
Location: Palm Harbor, Florida
Posts: 35
Liked 6 Times on 5 Posts
Likes Given: 3

Default

Quote:
Originally Posted by Majd
Quite genius fix, I like it particularly because I have two of those computer disk magnets available. I just want to know how did you position those crescent shapes over the earth magnets? Do you have a picture or a diagram?

Thanks
I don't have a picture right now. I can take one on Friday if you need one, But I don't think you will need it. The magnets naturally centered themselves on the rare earth magnets. I had to help them move around, because of the friction, but they sort of wanted to to rest in the correct position. Try it and if you need it I will post some pic's over the weekend.
unclevername is offline
 
Reply With Quote
Old 04-25-2013, 03:37 AM   #7
Majd
Feedback Score: 0 reviews
Recipes 
 
Join Date: Jun 2012
Location: Santa Clarita, California
Posts: 87
Liked 2 Times on 2 Posts
Likes Given: 2

Default

Quote:
Originally Posted by unclevername

I don't have a picture right now. I can take one on Friday if you need one, But I don't think you will need it. The magnets naturally centered themselves on the rare earth magnets. I had to help them move around, because of the friction, but they sort of wanted to to rest in the correct position. Try it and if you need it I will post some pic's over the weekend.
Thanks a lot. I will try it and let you know.
Majd is offline
 
Reply With Quote
Old 04-25-2013, 04:01 AM   #8
Gammon N Beer
Feedback Score: 0 reviews
Recipes 
 
Join Date: Dec 2007
Location: WI
Posts: 725
Liked 10 Times on 10 Posts
Likes Given: 40

Default

I have a, "cow magnet". Once my wort is cooled and ready for the stir plate I pitch the yest. I then tip the flask so the stir bar that has been in the flask for before the boil drops. At that point I use my external cow magnet to grab that stir bar and I can now see clearly see it.

I then remove my cow magnet and lower & move the flask over my stir plates magnet. I can hear the stir plate magnet, "grab" the stir bar and I position the flask and bar over the center of the stir plate. I then slowly turn the plate on and I get the result I need.

Play with it.
Gammon N Beer is offline
 
Reply With Quote
Old 04-25-2013, 04:09 AM   #9
Sacdan
HBT_SUPPORTER.png
Feedback Score: 1 reviews
 
Sacdan's Avatar
Recipes 
 
Join Date: Jul 2009
Location: Sacramento, CA
Posts: 911
Liked 18 Times on 16 Posts
Likes Given: 1

Default

Simple solution. Put an o-ring on the stir bar in the center. I had a lot of issues with my stir plate throwing the bar until I out on an o-ring. Try it. I'll bet it fixes your issue.
Sacdan is offline
 
Reply With Quote
Reply


Thread Tools


Similar Threads
Thread Thread Starter Forum Replies Last Post
Will these magnets work for stirplate? cbehr Chillers and Stir Plates 5 07-27-2012 12:43 PM
AG: Will my set up work properly? phoenixs4r Beginners Beer Brewing Forum 7 06-28-2011 05:20 AM
Stir Plate Question - Will this work properly? DannPM Equipment/Sanitation 5 03-17-2011 02:22 AM
My stirplate won't work because I am a moron eager_brewer Chillers and Stir Plates 8 02-26-2010 04:06 AM
Fermenting properly? timmystank Beginners Beer Brewing Forum 2 04-15-2009 04:35 PM


Forum Jump

Newest Threads

LATEST SPONSOR DEALS