Magic Pie to Lemon Meringue Pie

[dallasdick]

 ;DI have been thru three internal controllers since May (when I received my MPIII) and now I have really big problems .  First off I must say I have had this Pie apart changing controllers and cleaning out magnet fragments frequently.  In my last post I mentioned the scarring on the magnets and was told it was from hitting a curb too hard, which would make perfect sense if I had actually hit a curb, but I have never bumped my front rim into anything other than a few shallow potholes since I got it.

This last time I had a controller failure, I also was hearing a strange noise and getting a thumping and popping sound coming from inside the cover.  When I took the pie apart I inspected it thoroughly with these results:

1. fried controller, no 5v signal to throttle again (3rd time)
2. more magnet chips throughout the casing.
3. two stress-cracked motor spokes (see attached photos)
4. outer race of main bearing spinning against the motor cover housing. No more press fit.

These problems have been ongoing since I first received the pie, which I purchased from BMS Battery.com.  Which I found out do not handle warranty issues.  I have had terrible service from them.  David and Phillip, on the other hand, have been great responders to my earlier issues and sent me controllers.

The only way I can explain the cracked motor spokes and the thumping (out of round) problem is that the motor and wheel were dropped hard in shipping onto one end of the axle, which in hindsight explains why I had to retrue the wheel before the first ride, never getting the hump out of it.  Having no experience with BMS, Magic Pie or Golden Motor previous to this purchase, I gave the benefit of the doubt when I had my first failure on the first day.

Suffice to say, I should have done a much closer inspection of the unit when received, but who takes a motor apart to inspect it for shipping damage?  Now I have a really cool-looking boat anchor from a catastrophic failure 3 1/2 months in the making.  I never noticed the motor spoke stress cracks until the spokes were virtually severed from the hub housing.  Any suggestions?

I thought about having the casting welded but this is a warranty violation.

Thanks in advance for reading me vent,  I think I'll be chalking this one up to a poor experience and eat this lemon meringue pie now. Bon Appetit!

[Morgen 3Eman]

Is it the motor flange where the spokes hooked ends are that is cracked?   Or are you talking about some internal spoke structure?  I don't see a photo.

TTFN,
Dennis

[dallasdick]

here is a pic of the damages

[dallasdick]

Is it the motor flange where the spokes hooked ends are that is cracked?   Or are you talking about some internal spoke structure?  I don't see a photo.

TTFN,
Dennis

Thanks for the response Dennis, I posted a pic of the motor casting showing two of the casting spokes with complete cracks thru the point of attachment on the casting hub.  This motor/wheel assembly had to have been dropped on an axle end and then packed and shipped.  Takes a hell of an impact to draw stress cracks on the casting like that.  They had to have started as hairline cracks because as many times as I've had it apart I never noticed them before.  All the symptoms were there though, warped wheel when I got it.  Had to loosen all spokes and true the wheel by hand, vibration developing over time, motor off center and scraping magnets, leaving scars. 

I'm having hallucinations of me repairing it with JBWeld.  I doubt the factory will warrant it since I bought it from BMSBattery and they don't handle any warranty stuff. Is Phillip the best contact to inquire about shipping it back for warranty work?  I hate the idea of being without transport for 2 months while it is repaired and shipped back.

[Morgen 3Eman]

Hi Dallas,

If you can get warrantee service on it, that should be that path to take. 

However, if you get no joy from them, what do you have to loose by trying something else? 

Another fellow has tried arc welding his broken casting problem, very similar to yours, and that was not successful.

You should take everything else I'm about to say with a huge grain of salt, because I have not had my hands and eyes on the actual problem.  So I don't really know what I'm talking about.

But, if it was mine, I would:

First see if the various cracked bits and pieces can be positioned and held so they are in good alignment.  If part of the stator is half an inch out of plane, and can't be brought back, there is nothing to fix.  Out of round is no good, etc. 

Then I would shape some sheet metal to form a web from spoke to spoke.  And some more to make half tube shapes, probably tapered to fit directly and fairly closely to the actual shape of the cast spoke at the break.  The more square inches you can reinforce the better.  The more complex you can make the sheet metal shapes, the better.   A good way to start figuring all this stuff out is to use card stock, like the cereal box in your kitchen.  You can cut it and shape it, and then use it as a pattern to make the sheet metal the right shape. 

Then I would use sandpaper and cleaning materials to clean and abrade every surface to be bonded.  And then I would clean them again, and never handle them again without clean rubber gloves on my hands.

I like JB-Weld, because it is slow and forgiving, but you can use any epoxy you prefer.  Test fit everything to figure out a good sequence to put them all together, and figure out where and how to clamp everything so it doesn't move while the epoxy sets up.   (One thing that has worked for me in this kind of situation is to use wooden stiffeners and hot melt glue to hold stuff.  My hot melt is fairly low peel strength so it is pretty easy to remove.  )

Once you are sure you can get everything to fit together, epoxy it all up, clamp it(being careful not to squeeze all the epoxy out of the joint) and then put it in a warm place and leave the damn thing alone for at least a day, and the longer you leave it the better.  Don't pick it up and see if it is curing, etc, as that is just asking to weaken the bond joint. 

You can see what else you have to do.....

TTFN,
Dennis

[dallasdick]

Thanks Dennis for the inspiration. I'm actually a pretty good fabricator and I love the sheetmetal spoke fillers. I have some nice .001 brass sheet stock to make the cylinder molds for the spoke to hub connection. Glue gun?  Oh yea! Have Dremel will travel.

First things first though, get ahold of the factory, it is in warranty for several more months.  Good to have an excellent back up plan.  Thanks for your input, Dennis.  I knew someone on the forum had some insight on this issue.

[skylinenitro]

I had your exact same problem, but I tried to arc weld some metal to everything and anything that I could... Turns out that the heat made everything worse and made my circle not a circle... I now have an empty hub that has no stator that I ride on (with human power ) until my new hub arrives from Gary at GM Canada. 

Good luck to you sir!  I might try to make a windmill out of my old broken stuff...

[skylinenitro]

http://goldenmotor.com/SMF/index.php?topic=4448.msg25890#msg25890

That's the link to my posts and failed pictures.  Big pothole!  Like the ones that eat cars for breakfast...

[Morgen 3Eman]

Hi Dick,

I'm hoping you get some warrantee satisfaction,  that is the best path forward.   

 .001 brass  is no where near strong enough.  You need to be thinking .020-.030 steel kind of strength. 

TTFN,
Dennis

[dallasdick]

Hey Dennis,

I've been waiting for Golden Motor China to respond to my warranty claim since September 12, when I last posted to this thread.  I am reluctant to try plan B until I get a response to my request for a new stator assembly.  I guess I need to send a follow up email.  Does anyone have a specific email address that will get me in touch with a warranty claims rep?  I think my last email was to the sales dept. and perhaps it wasn't forwarded to warranty claims.

This 26" rim is impossible to true.  I have tried everything to get the hump out of it, it's eccentric by almost 3/16" at its highest point and even loosening all the spoke and re-truing it twice has not substantially taken the hump out of it.  I am certain the internal damage was due to the wheel or hub being dropped on the end of the axle, but the rim was able to be trued from side to side, but not a perfect circle, never was a perfect circle.

[Morgen 3Eman]

Alan may know about warrantee help.

I figured it would be simpler to show you some 3D CAD figures of the reinforcements I was commenting on. 

TTFN,
Dennis

[Bikemad]

Does anyone have a specific email address that will get me in touch with a warranty claims rep?  I think my last email was to the sales dept. and perhaps it wasn't forwarded to warranty claims.

I would suggest you send an email to David (wyh@goldenmotor.com) containing your original order details and a brief description of you problem accompanied by some pictures of the failed stator.
If David is unable to deal with it himself, he should at least be able to pass it on to Philip, or whoever is responsible for processing/authorising legitimate warranty claims.

Alan
 

[dallasdick]

Thank you Alan, for the email to David.  I just sent a second request to Philip, but I'll duplicate it to David.  Perhaps David is more responsive to these warranty issues. I appreciate your help with this.

[dallasdick]

Great news...David is shipping me a new stator to replace my boat anchor. Yipee!  Hope that gets me squared away properly.  Thanks to everyone who chimed in with their expertise. I love this forum!