Benvarine's DIY stir plate build
  • BenvarineBenvarine
    Posts: 1,606
    A little wobble because the tape folds are not consistent. Double stick would be better here
  • ThymThym
    Posts: 122,708
    Benvarine said:

    A little wobble because the tape folds are not consistent. Double stick would be better here



    double stick would definitely be better. you got and ACE or something nearby?
    The only thing between me and a train wreck is blind luck..... - Kenny
  • ThymThym
    Posts: 122,708
    we gotta get rid of the woble before we move on.
    The only thing between me and a train wreck is blind luck..... - Kenny
  • BenvarineBenvarine
    Posts: 1,606
    Went with one fold. Seems to hol
  • ThymThym
    Posts: 122,708
    my recco is to use the tape to hold it temporarily while we align things, then a spot of super glue for testing.
    The only thing between me and a train wreck is blind luck..... - Kenny
  • ThymThym
    Posts: 122,708
    Benvarine said:

    Went with one fold. Seems to hol



    good
    The only thing between me and a train wreck is blind luck..... - Kenny
  • ThymThym
    Posts: 122,708
    get the alignment nailed. make sure the top surface is flat too. you might need to sand it down a bit. wobble in any direction is your enemy.
    The only thing between me and a train wreck is blind luck..... - Kenny
  • BenvarineBenvarine
    Posts: 1,606
    Top of the box? It's flat. Or top of the cap. Seems flat too.
  • ThymThym
    Posts: 122,708
    Benvarine said:

    Top of the box? It's flat. Or top of the cap. Seems flat too.



    top of cap, when its spinning on the fan, it should remain totally flat.
    The only thing between me and a train wreck is blind luck..... - Kenny
  • ThymThym
    Posts: 122,708
    in other words it needs to be true planar and perpendicular to the fan's axis of rotation
    The only thing between me and a train wreck is blind luck..... - Kenny
  • BenvarineBenvarine
    Posts: 1,606
    It looks pretty flat, it will improve with better tape as well or when I glue it down. I attached the magnet with tape too. Is that right?
  • ThymThym
    Posts: 122,708
    Benvarine said:

    It looks pretty flat, it will improve with better tape as well or when I glue it down. I attached the magnet with tape too. Is that right?



    yeah. same deal here, except, the shape of that magnet will always make it wobble. what you are looking for is the stir bar not wobbleing.. so attach the stir bar to the magnet, magnet to the cap then turn on the fan and make sure the stir bar spin perfectly centered
    The only thing between me and a train wreck is blind luck..... - Kenny
  • ThymThym
    Posts: 122,708
    making sure the stir bar is centered at this step is the most critical part.

    you make need to glue the cap down to the fan first for it to be stable enough to perform this step
    The only thing between me and a train wreck is blind luck..... - Kenny
  • BenvarineBenvarine
    Posts: 1,606
    When I add the stir bar to the magnet, it wobbles. Looking from the side there is considerable wobble. Looking down not so much. I think it's the tape. But also the weight of the stir bar spinning is causing the tape to pull.
  • ThymThym
    Posts: 122,708
    Benvarine said:

    When I add the stir bar to the magnet, it wobbles. Looking from the side there is considerable wobble. Looking down not so much. I think it's the tape. But also the weight of the stir bar spinning is causing the tape to pull.



    the weight only pulls because it's off center.

    but lets fix it. sounds like the spacer is sufficient for the fan motor to run properly with all of the magnets, so we can firmly attach the space to the fan. glue that tinhg down if it still looks centered
    The only thing between me and a train wreck is blind luck..... - Kenny
  • BenvarineBenvarine
    Posts: 1,606
    It will spin well on top of the box, slight wobble in the bar.

    When the bar is in the flask empty, it will spin, picks up more wobble at higher speeds
  • ThymThym
    Posts: 122,708
    Benvarine said:

    It will spin well on top of the box, slight wobble in the bar.

    When the bar is in the flask empty, it will spin, picks up more wobble at higher speeds



    we need to get 0 wobble. if you can see tell that it's wobbling, it's way too much.
    The only thing between me and a train wreck is blind luck..... - Kenny
  • BenvarineBenvarine
    Posts: 1,606
    I don't have super glue. Only gorilla, it's slow mad expands. I'll need to get some.
  • scoobscoob
    Posts: 16,617
    Lakewood said:

    making sure the stir bar is centered at this step is the most critical part.

    you make need to glue the cap down to the fan first for it to be stable enough to perform this step


    This is where I like 5 minute or 10 minute epoxy, gives you some time to center things perfectly before it sets up
    Jesus didn't wear pants
  • BenvarineBenvarine
    Posts: 1,606
    What to you think is off center, the magnet?
  • ThymThym
    Posts: 122,708
    there will always be some wobble, if we were to put the thing on a balancer, even after we think it's "perfect" the balancer would tell us we suck at balancing stuff
    The only thing between me and a train wreck is blind luck..... - Kenny
  • ThymThym
    Posts: 122,708
    Benvarine said:

    What to you think is off center, the magnet?



    yes, the magnet is where we should do the adjustment. but you need to firmly attach the spacer to the fan first
    The only thing between me and a train wreck is blind luck..... - Kenny
  • ThymThym
    Posts: 122,708
    Benvarine said:

    I don't have super glue. Only gorilla, it's slow mad expands. I'll need to get some.



    dont use that crap. do you have a hot glue gun?
    The only thing between me and a train wreck is blind luck..... - Kenny
  • BenvarineBenvarine
    Posts: 1,606
    Centering the cap will be easy. It's almost perfectly the same size as the center of the fan. The magnet will be hard. Should I get a new one, that's straight?
  • ThymThym
    Posts: 122,708
    Benvarine said:

    Centering the cap will be easy. It's almost perfectly the same size as the center of the fan. The magnet will be hard. Should I get a new one, that's straight?



    that would be easier... but life is full of challenges we can handle this one.
    The only thing between me and a train wreck is blind luck..... - Kenny
  • ThymThym
    Posts: 122,708
    Lakewood said:

    Benvarine said:

    Centering the cap will be easy. It's almost perfectly the same size as the center of the fan. The magnet will be hard. Should I get a new one, that's straight?



    that would be easier... but life is full of challenges we can handle this one.


    dont think of it as centering the magnet, think of it as centering the stir bar.
    The only thing between me and a train wreck is blind luck..... - Kenny
  • ThymThym
    Posts: 122,708
    attach the stir bar to the magnet and use it to decide where to place the magnet.

    as long as the stir bar snaps to one and only one position on that magnet it will work.
    The only thing between me and a train wreck is blind luck..... - Kenny
  • ThymThym
    Posts: 122,708
    of course you will be forever conscribed to use that exact size of stir bar.
    The only thing between me and a train wreck is blind luck..... - Kenny
  • ThymThym
    Posts: 122,708
    if you attach one that is any bigger or smaller the curve of the magnet will change the location of the bar relative to the spin center.
    The only thing between me and a train wreck is blind luck..... - Kenny
  • BenvarineBenvarine
    Posts: 1,606
    I get it. I'm going to lowes. I'll get epoxy and start again. Anything else while I'm out?
  • ThymThym
    Posts: 122,708
    oh, and you should have super-glue. super-glue is a necessary staple.
    The only thing between me and a train wreck is blind luck..... - Kenny
  • BenvarineBenvarine
    Posts: 1,606
    I bought two different sizes of bars, the larger one wont work at all. Every test I did it had problems.
  • ThymThym
    Posts: 122,708
    Benvarine said:

    I get it. I'm going to lowes. I'll get epoxy and start again. Anything else while I'm out?



    i could use a few things for my boat, but i'll pick them up later.
    The only thing between me and a train wreck is blind luck..... - Kenny
  • BenvarineBenvarine
    Posts: 1,606
    Right, epoxy and super glue
  • BenvarineBenvarine
    Posts: 1,606
    And double sided tape just in case
  • ThymThym
    Posts: 122,708
    Benvarine said:

    Right, epoxy and super glue



    yuo might need some longer screws and spacers to mount the fan in the box now
    The only thing between me and a train wreck is blind luck..... - Kenny
  • ThymThym
    Posts: 122,708
    Benvarine said:

    And double sided tape just in case



    yeah, i get the 3M stuff that is about 1/16th of an inch thick grey foam. it's called VHB
    The only thing between me and a train wreck is blind luck..... - Kenny
  • ThymThym
    Posts: 122,708
    it's fantastic stuff.
    The only thing between me and a train wreck is blind luck..... - Kenny
  • ThymThym
    Posts: 122,708
    Lakewood said:

    it's fantastic stuff.



    a bit expensive, but it'll last forever, it doesn't take much to make something stick
    The only thing between me and a train wreck is blind luck..... - Kenny
  • scoobscoob
    Posts: 16,617
    Lakewood said:

    Lakewood said:

    it's fantastic stuff.



    a bit expensive, but it'll last forever, it doesn't take much to make something stick


    I use this in the shop a lot, truly handy stuff indeed!
    Jesus didn't wear pants
  • BenvarineBenvarine
    Posts: 1,606
    I attached the cap with epoxy. Attached the magnet with double stick tape. It should hold, it's rated to 2lbs.

    I adjusted a few times and it spins the water, no better than last night, but the bar isn't being thrown. I had to pull the trigger and go for its first test drive. I have a brew tomorrow and needed to get the starter, well, started.

    I'm afraid to try and ramp up the speed because I don't want to start all over again with another fan, magnet, wobble problem.
  • ThymThym
    Posts: 122,708
    If its not wobbling you should be able to increase the speed to see if you can get the bigger vortex. No wobble means faster spin before being thrown.
    The only thing between me and a train wreck is blind luck..... - Kenny
  • scoobscoob
    Posts: 16,617
    Honestly, a full vortex is mostly for show, a whirlpool with a dimple will be more than adequate to properly oxygenate the starter for good yeast propagation.

    It's not about the impressive vortex, but rather the stirring of the whirlpool that allows the oxygenation.

    Jesus didn't wear pants
  • scoobscoob
    Posts: 16,617
    You will be fine with your starter..

    Nothing like a trial by fire eh?
    Jesus didn't wear pants
  • BenvarineBenvarine
    Posts: 1,606
    Thanks for all the help guys. The stir plate ran all night, still spinning now. Seems to be working fine. One step for man, one giant leap for this home brewer.
  • frydogbrewsfrydogbrews
    Posts: 44,679
    Benvarine said:

    Thanks for all the help guys. The stir plate ran all night, still spinning now. Seems to be working fine. One step for man, one giant leap for this home brewer.



    glad this all got worked out.....since i plan on borrow it.

    not the concept, the actual unit.
  • BenvarineBenvarine
    Posts: 1,606
    We will just need to stager our brew days, I brew every other week, tonight is a brew day. But you probably brew during the week, when you are supposed to be at work.
  • frydogbrewsfrydogbrews
    Posts: 44,679
    Benvarine said:

    We will just need to stager our brew days, I brew every other week, tonight is a brew day. But you probably brew during the week, when you are supposed to be at work.


    no, that's when i hunt.
  • scoobscoob
    Posts: 16,617
    frydogbrews said:

    Benvarine said:

    Thanks for all the help guys. The stir plate ran all night, still spinning now. Seems to be working fine. One step for man, one giant leap for this home brewer.



    glad this all got worked out.....since i plan on borrow it.

    not the concept, the actual unit.


    hmm, people in need of stirplates.... Gives me an idea
    Jesus didn't wear pants
  • BenvarineBenvarine
    Posts: 1,606
    I'm back to building another one. All wired, spins bar just fine on the plate, but once I put it in the flask, throws every time. I've tried moving the fan and magnets further and closer from the plate. No luck. Suggestions?
  • ThymThym
    Posts: 122,708
    Benvarine said:

    I'm back to building another one. All wired, spins bar just fine on the plate, but once I put it in the flask, throws every time. I've tried moving the fan and magnets further and closer from the plate. No luck. Suggestions?


    3 keys:
    Magnet spacing = stir bar magnet spacing
    Magnet distance = as small as possible
    Magnet strength = as strong as possible
    The only thing between me and a train wreck is blind luck..... - Kenny
  • BenvarineBenvarine
    Posts: 1,606
    I got it sorted out. I used a smaller power cord, only 5v output. I moved the magnets closer and it works, but it does not spin fast, I have a rheostat on it, but it is turned down. When I crank it up, it throws.
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