i made a mistake

[blueyonder]

  i lost the plot .

   when making a second rotor  i thought it will be easy.

   as ive made one before.  all i had to do was make a second one  just as i

 had made the first one.

   i got the mould out and gave it a clean up and polish.

    cleaned the steel backing with acetone . glued the mags on with two part epoxy.

  waited till it set.    got the chopped strand mat cut up and mixed the resin.

  made sure every thing was good to go. then  potted it and put the lid on tight.

   this time things were much better . it was warm and sunny outside.

  not cold and winter time.

   so on to opening the mould .  it had cast very well so i thought.

  all i had to do was clean it up a bit.

   now i saw sumthing was very odd . so much flux leakage out the back of the rotor.

    same 8mm steel  same mags  same resin .  

   every thing was the same as the other one i made.

   but first one had so little flux leaking out the back .

  i was going to put a post on here asking why one rotor had none and other was very strong leaking out the back.

  but thinking how would any one on here know why this was like this.

   if i dident know then how was sumone on a pc going to help.

   i was puzzled .   just checking the poles again i found thay were all the same.

    with a small magnet in my hand i went round and round.

     bad magic here. it was impossible for this to happen .

    i looked about for gremlins and other such things.

  tried it again and still the magnet in my hand was pulled by each magnet it passed.

  the rotor looked a good one.

  but it had one problem . all the poles were the same way up.

  so now i understand what was wrong. i had made a mistake .

   i only used a small mag to check out the 2x1" when setting out.

  my hand cant make a fist  so when i tried it on the first rotor

 i made  i saw the magnet flip over in the palm of my hand.

  thinking  back i had used a 2x1" to check the  north and south.

    that i could hold in my fist ok.

    i felt very unhappy.   very sad very stupid.  and a wee bit angry with myself.

   but it wasent the end of the world . i just got busy trying to work out how

  to put it right.  

    and i did put it right .   no magic smoke came from anywhere so that ment

 i could repair it.

   yes its a stupid thing i done.  maybe you can roll on the floor laughing if you want to.

   heres sum pics just to prove i did repair it

   when i got the mags of the steel backing it pulled sum plating of the mags.

  the nickil stuff.  but its all potted up well now. so should be ok.

   wasent easey trying to use the template as it was the first time. to relocate the mags in place.

     











  so life aint so bad when you can fix your mistakes.

  well sum of them anyway

[windy]

blueyonder

The best teacher is the mistakes we all make. Glad to hear you got it repaired!

windy

[Flux]

Always check first before potting. As I read through this I guessed that you had reversed at least some of the magnets, that is about the only thing that would cause the leakage.

I am pleased that you managed to rescue the situation, that is one mistake you will not make again.

One of those things that comes with experience. I have several easy methods to make sure I don't do this but I deal with magnets daily for other reasons. I find the simplest method apart from the fluxmeters and search coils is to hold a decent sized neo magnet in the fist and pass it over the mounted magnets to see that it alternately attracts and repels. As long as you have the thickness of your fingers between the test magnet and the rotor you are checking it is perfectly safe, but even so I suspect someone not understanding exactly what to do could screw it up and hurt themselves so use your own discretion.

Flux

[TomW]

blue;

Sharing the mistakes is actually more important than sharing the successes.

I think most folks just slink away or hide the mistake because they are embarrassed or something.

Thanks for the share.

Such a simple "oops" such a butt pain to make it right.

Glad you rassled it to the ground and fixed it. And, as Flux said, you will never make that mistake again so you learned a valuable lesson that will stick with you for life.

Tom

[vawtman]

Hi Yonder

 Glad you got her fixed.You have the patience it takes to build a turbine.

 I do like flux states.

 Set one mag on the rotor.For the next mag(fisted in hand)if it attracts to that mag i know its an opposing pole so just flip it and install it next.

 I can tell from about 4in away so no finger problems.

 I'm workin with 54 poles.Kinda cool has you go around.

 Mark

[spinningmagnets]

Dear blueyonder, I agree with all the previous.

Easy to crow about our successes. Ten identical success stories are encouraging, but not neccessarily helpful. You have allowed me to learn from your mistakes, and I am grateful. Thank you.

[blueyonder]

 

   so i put a post on here about me making a mistake.

   and no one was harsh with me. good.

   i did try to be clever and sort out the poles with a marker pen.

   one pole red one blue.   so four of each .

    then- the the deadly sin . i never made sure.

    just got busy and got it nicely potted . you know the rest  he he.  

[vawtman]

Yonder

 You admitted to making a goof and freely admitted it,thats cool.

 Most would hide in a crack somewhere.

 I remember after i built my turbine it would spin at 60rpms in a 10 mph wind and for some newbie dummie reason i thought it had a tsr of 6.

 Learned alot and apologized.

 Hey if you don't make mistakes how can you learn anything?

[blueyonder]

  vawtman i understand you. my mill runs at 120 rpm in 20mph wind.

   and has a tsr of 12.  so i must be doing it right.