Tack weld BMC/MAC Clutch

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snowranger   10 kW

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Tack weld BMC/MAC Clutch

Post by snowranger » Oct 19 2015 1:39pm

My clutches have been breaking so often that I am thinking about throwing in the towel and tack welding them.

I have been playing around with a 50 amp 120V stick welder but cannot get enough penetration to make a weld. I am a newbie welder BTW.

Has anyone else done this? Should I get a 1/16" welding rod?

TIA
Electric: BBS02 / Nuvinci Developer Kit / 14s Li
Bike : Yuba Mundo
Accessories: 12 volt lighting, 48V horn
Miles: 300 mi

rider95   1 kW

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Re: Tack weld BMC/MAC Clutch

Post by rider95 » Oct 19 2015 3:55pm

LOL

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voicecoils   10 MW

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Re: Tack weld BMC/MAC Clutch

Post by voicecoils » Oct 19 2015 3:58pm

I've seen it done and work reliably for some several thousand km.

Your plastic/composite gears and key on the shaft will be the next weakest links.

Just take it to someone with a beefy welder, 3min job

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snowranger   10 kW

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Re: Tack weld BMC/MAC Clutch

Post by snowranger » Oct 20 2015 8:43am

Thanks. I'm not running excessive power. My daughter just likes to jam on the throttle.
Electric: BBS02 / Nuvinci Developer Kit / 14s Li
Bike : Yuba Mundo
Accessories: 12 volt lighting, 48V horn
Miles: 300 mi

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voicecoils   10 MW

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Re: Tack weld BMC/MAC Clutch

Post by voicecoils » Oct 20 2015 3:08pm

snowranger wrote:Thanks. I'm not running excessive power. My daughter just likes to jam on the throttle.
No worries, just keep in mind the motor will always be spinning afterward the mod so the extra drag from it will cause you to drain the battery a bit faster.

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sonnetg   1 kW

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Re: Tack weld BMC/MAC Clutch

Post by sonnetg » Oct 20 2015 8:42pm

I never had any issues with geared motors, but I am very conservative with the throttle. I never even use the throttle from a dead stop, or at least try not to. It sure would be a bummer if my geared motor had such failures.

If this helps, I found a youtube video of someone welding the clutch. Welding is the easy part, but I am not sure how easy it would be to align or center the clutch before tack welding it. You could probably show this video to the local weld shop and inquire.. [Fast forward to 20:34 to see the welding process]


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snowranger   10 kW

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Re: Tack weld BMC/MAC Clutch

Post by snowranger » Oct 23 2015 5:31pm

Thanks. I watched the video. Not as easy or straightforward as I thought. There seems to be a couple different versions of clutches out there.
Electric: BBS02 / Nuvinci Developer Kit / 14s Li
Bike : Yuba Mundo
Accessories: 12 volt lighting, 48V horn
Miles: 300 mi

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