Author Topic: Help!! Broken Stator!! MPII External  (Read 7188 times)

Offline skylinenitro

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Help!! Broken Stator!! MPII External
« on: July 15, 2012, 04:53:31 PM »
I pulled my pie apart to replace some bad hall sensor cables and found this!

Should I weld the piss outta it, or is it junk?

There was minimal scraping on the magnets, no chips or broken parts.  And some of the stator fins were bent, but I was able to bend those back okay.  I musta hit a good pothole... surprised that I didnt fly face first over the handle bars...

You can see it broke at 2 places (where those #%$@ screw holes are) and there are stress cracks spiderman style elsewhere.  The whole stator is straight and spins okay (after I pushed everything back together (those bite marks are from my tools)).

So I am working on getting as much metal as I can that will fit in the hub and weld the piss outta it. 

What do you think?
Live Long and Prosper

Offline Morgen 3Eman

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Re: Help!! Broken Stator!! MPII External
« Reply #1 on: July 15, 2012, 06:10:42 PM »
As a recent student of how welding heat can distort metal structures, I would not follow your path of "Welding the piss out of it". 

Aluminum is prone to stress cracking.

Please feel free to ignore anything I say, but here is how I would proceed.

I would get some .020" to .050" thick steel sheet or strip.  I would cut "V"  and "U" shaped pieces to fit about the hub, and semi-tubular bits to fit over the fin shaped stiffening areas.  I would carefully but aggressively abrade all the aluminum places where the steel will cover,  maybe 40-60-8- grit sandpaper would do a good job.  Then meticulously clean all the stuff previously handled, mix up some J-B Weld, and reinforce all the cracked areas with the steel and J-B Weld.  I would make sure everything was well clamped so nothing could shift about while the Weld cures, and let it sit in a warm dry place for three days.  Then check for and eliminate any interference problems, put everything together and go ride the piss out of it.

TTFN,
Dennis

Offline Morgen 3Eman

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Re: Help!! Broken Stator!! MPII External
« Reply #2 on: July 15, 2012, 08:03:54 PM »
This is how old timers do CAD  Cardboard Aided Design....:)

This is the shapes I was referring to .  Make sense now?

TTFN,
Dennis

Offline skylinenitro

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Re: Help!! Broken Stator!! MPII External
« Reply #3 on: July 15, 2012, 08:09:22 PM »
Cardboard!! Fantastic!! I will give that a shot and let you know, thank you!  Ohh, and I don't have JB Weld but I already started a lil some some with a MIG welder.  I can only go so fast because of the heat and I don't want to distroy the rotor more ;)
Live Long and Prosper

Offline Morgen 3Eman

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Re: Help!! Broken Stator!! MPII External
« Reply #4 on: July 15, 2012, 09:51:05 PM »
If you weld Aluminum a lot, you already know how easy it is to warp.  Good luck with it. 

TTFN,
Dennis

Offline Morgen 3Eman

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Re: Help!! Broken Stator!! MPII External
« Reply #5 on: July 15, 2012, 09:56:19 PM »
By the way, with all the cracking I see in the photos, I'd still be tempted to reinforce the webs with some sheet steel.

TTFN,
Dennis


Offline skylinenitro

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Re: Help!! Broken Stator!! MPII External
« Reply #6 on: July 15, 2012, 10:07:40 PM »
By the way, with all the cracking I see in the photos, I'd still be tempted to reinforce the webs with some sheet steel.

And not just cardboard?

Kidding :)
Live Long and Prosper

Offline Morgen 3Eman

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Re: Help!! Broken Stator!! MPII External
« Reply #7 on: July 15, 2012, 11:41:21 PM »
Well, I will admit to using cardboard as a core for some fiberglass stuff .   As long as it doesn't get wet, it is surprisingly light and strong.  With a glass skin, it is really rigid. 

I'm seriously planning on using hollow polycarbonate panels with a carbon fiber skin for making parts of limited production versions of my Morgen.   I still have to do a lot of proof work, but sofar it looks very good.  Light, stiff, tough.  Did I mention light? I found one incredible weakness to polycarbonate, however.  I was going to use acetone to clean the surface of body oils, etc, when I spilled a puddle of it on a poly panel.  The panel started cracking like crazy while I was wiping it up!   It is amazing what one can learn while making mistakes...

TTFN,
Dennis

Offline skylinenitro

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Re: Help!! Broken Stator!! MPII External
« Reply #8 on: July 16, 2012, 02:02:57 PM »
I welded the piss outta it.  Now I gotta grind down some nasty overfill :)

I also found that all but one of the stator fins were broken, so I added about 10 pounds of steel to reinforce the whole bloody thing.

Pictures to come
Live Long and Prosper

Offline Morgen 3Eman

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Re: Help!! Broken Stator!! MPII External
« Reply #9 on: July 16, 2012, 06:55:56 PM »
Where did you find room for 10 Lbs of steel, and how did you attach it all?   

Come on, show us the photos!  10 Lbs!  Really!

(Please show us the photos)

TTFN,
Dennis

Offline skylinenitro

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Re: Help!! Broken Stator!! MPII External
« Reply #10 on: July 16, 2012, 07:05:46 PM »
Okay, maybe 10 lbs is a little excessive... But I cramed a buttload of steel in there.  Thank you GM for being cheep and making one pie for the internal and external controllers.  The space in the pie where the internal controller should go doesnt have the reinforceing ribs, and thats where most of the steel went.  Then I spidered it out from there :)
Live Long and Prosper

Offline skylinenitro

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Re: Help!! Broken Stator!! MPII External
« Reply #11 on: July 17, 2012, 03:25:39 AM »
Now, just a warning, its not pretty, but itll work.  I still have to clean it up and grind some stuff down...
Live Long and Prosper

Offline Morgen 3Eman

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Re: Help!! Broken Stator!! MPII External
« Reply #12 on: July 17, 2012, 04:15:22 AM »
May I ask how you managed to weld steel to aluminum? 

TTFN,
Dennis

Offline skylinenitro

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Re: Help!! Broken Stator!! MPII External
« Reply #13 on: July 17, 2012, 06:31:10 PM »
I'm not sure to be honest, I used a MIG welder on its second highest power level.  The solder sticks to the aluminum well by its self, so maybe the cast aluminum is an alloy and has some steel in it?
Live Long and Prosper

Offline Morgen 3Eman

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Re: Help!! Broken Stator!! MPII External
« Reply #14 on: July 17, 2012, 09:43:48 PM »
I wish you the best with your stator, but I know of no supplies or method for mig welding steel to aluminum.  I think I'll do some Googling.

TTFN,
Dennis