QS 205 V3 Axle replacement method

[xylene23nyc]

I was wondering if anyone has successfully replaced a broken Axle on a Qs205 V3 Hub Motor?

Did you need a hydraulic press or was a certain sized gear puller sufficient? I have a replacement Axle on the way and could use any tips.

I am a recent victim of a nasty NYC pothole. Dual suspension won't save you here.

 

[amberwolf]

I have not yet installed the new axle, so don't know for certain, but it should be possible to cool (freeze) the axle, and warm the stator, and gain sufficient clearance to either just slip it right in, or gently tap it into place with a deadblow hammer and a wood block on the end of the axle, with a pipe (bigger ID than axle OD, but sized to fit against the stator's axle-core support so no stress is applied to any other part of the stator) between the stator and the surface you're pressing / hammering against.

If you have to use a gear puller, you're likely going to have to have the stator in the rotor with one side cover installed to have anything to pull against (spoke flanges), and use a spacer between stator (at the core around where the axle goes in) and side cover (to prevent squashing the windings), because you can't use the gear puller on the stator itself anywhere.

A press would let you setup a fixture under the stator so pressure is only applied at the core opposite to where the axle is going in, to prevent breaking or otherwise damaging the stator itself, windings, or support "spokes" between stator and axle-mounting core.

Removing the old axle is likely to require a press and a fixture as above, unless you can freeze the axle with CO2 or LN2, possibly while warming the stator support around it.

Before you try to remove the old axle, don't forget to remove the circlip securing it in place at the stator-axle support core.

Before you press in the new axle, don't forget to set the key into the keyway of the new axle, and align it correctly with the stator keyway.


An alternative that might be stronger for your application, depending on whether you use the freewheel mount, is to install a larger bearing on that side matching the one on the left side (may require using a left side cover as well, or modifying your existing right side cover), and using a "pipe axle" of that same large diameter all the way thru the stator and dropouts. You'd have to replace your dropouts with clamps that would secure it, but it would handle torque and impact better, with the much larger diameter, and makes passing the wires thru much easier, as well, as the entire axle is hollow.

See Farfle's custom dual-stator GoldenMotor Magic Pie thread for one way to do this.
https://endless-sphere.com/forums/viewtopic.php?f=30&t=34750&hilit=axle&start=225#p538389

I was wondering if anyone has successfully replaced a broken Axle on a Qs205 V3 Hub Motor?

Did you need a hydraulic press or was a certain sized gear puller sufficient? I have a replacement Axle on the way and could use any tips.

I am a recent victim of a nasty NYC pothole. Dual suspension won't save you here.

 

[xylene23nyc]

Thank you very much for this detailed info.

Once the Axle arrives ill likely ask Machine/metal shops around me about using their hydraulic press. Ill try to find a pipe or something similar to press against.

I'll do my best to document the process and share if successful.

 

[amberwolf]

A shop with such a press should be experienced at this kind of thing in general (if not motor axles specifically), so that should be a good choice.

Sharing any failures that happen would be helpful, too--I think I've learned many times as much from my many failures as my few successes.

 

[xylene23nyc]

This 8" gear puller worked great to help remove the stator.

I'm going to try using the gear puller to remove the Axle held in place with a vice. If it doesn't work then I'll go to a shop or buy a 10 ton hydraulic press to do it myself depending on what they charge.

Is that gray stuff silicone grease?

 

[amberwolf]

This 8" gear puller worked great to help remove the stator.

I'm going to try using the gear puller to remove the Axle held in place with a vice. If it doesn't work then I'll go to a shop or buy a 10 ton hydraulic press to do it myself depending on what they charge.

A warning before trying this, since it may damage or destroy the motor:

There is nothing on the stator you can definitely safely grab with the gear puller.

You can make a plate / tube that presses on the steel core area directly around the axle on the opposite side from the puller, and grab that with the puller, if it's jaws are long enough, but if you grab the stator laminations it will deform them (possibly just temporarily but enough to damage the windings) or slip and directly damage the windings. If you grab the stator support "spokes", they may snap. Hopefully this will not happen...but it has happened on other types of motors over the years to other people.

If the stator does get damaged / broken, please save the rotor and side covers--I'd buy them from you for the bare stator I have here, depending on cost and shipping.

Also, don't forget to remove the circlip on the axle before trying to remove it.

Is that gray stuff silicone grease?

It is probably silicone glue to fill gaps in the cable inlet to minimize water ingress and to glue thecable in place so it doens't get pulled out of the motor during any installation or usage.

 

[DogDipstick]

10 ton press.

 

[xylene23nyc]

This 8" gear puller worked great to help remove the stator.

I'm going to try using the gear puller to remove the Axle held in place with a vice. If it doesn't work then I'll go to a shop or buy a 10 ton hydraulic press to do it myself depending on what they charge.

A warning before trying this, since it may damage or destroy the motor:

There is nothing on the stator you can definitely safely grab with the gear puller.

You can make a plate / tube that presses on the steel core area directly around the axle on the opposite side from the puller, and grab that with the puller, if it's jaws are long enough, but if you grab the stator laminations it will deform them (possibly just temporarily but enough to damage the windings) or slip and directly damage the windings. If you grab the stator support "spokes", they may snap. Hopefully this will not happen...but it has happened on other types of motors over the years to other people.

If the stator does get damaged / broken, please save the rotor and side covers--I'd buy them from you for the bare stator I have here, depending on cost and shipping.

Also, don't forget to remove the circlip on the axle before trying to remove it.

Is that gray stuff silicone grease?

It is probably silicone glue to fill gaps in the cable inlet to minimize water ingress and to glue thecable in place so it doens't get pulled out of the motor during any installation or usage.

I'm going to take your advice and wait until I get the hydraulic press. C clip was removed. I'm sure a metal shop in NYC will charge me at least $100+ for the job and I can get a well reviewed harbor freight 12 ton press for $169. I get a feeling this wont be the only broken Hub Motor axle I will know about/deal with in NYC with our pothole ridden roads lol. I still don't know how people ride skinny tire bicycles here.

The gray stuff seems to be silicone grease? as its very soft still.

 

[amberwolf]

The gray stuff seems to be silicone grease? as its very soft still.

Silicone grease will smear around, and will not wash away with soap and water off your hands (or whatever you use to smear it with).

If it doesn't smear, but is rubbery (even if *very* soft), it's not silicone grease (at least none I have experience with, as all of them I've worked with contain significant amounts of silicone oil), but just silicone sealant (which can be made so soft that it is softer than the softest skin or other live tissue, though it tends to be fragile at that durometer level).

The stuff that came on both the axles I have and the stators is silicone sealant.

I'm going to take your advice and wait until I get the hydraulic press. C clip was removed. I'm sure a metal shop in NYC will charge me at least $100+ for the job and I can get a well reviewed harbor freight 12 ton press for $169. I get a feeling this wont be the only broken Hub Motor axle I will know about/deal with in NYC with our pothole ridden roads lol. I still don't know how people ride skinny tire bicycles here.

With the press, and the practice of fixing your own hub, you can then offer the service to others in the area to pay for the press.

 

[xylene23nyc]

It definitely smears and I assume they decided against a hard glue to make repairs like mine easier. With a hard glue there would be no access to the wires.

I will reseal with silicone grease.

Picking up a 12 Ton press on sale this weekend and will update here.

 

[amberwolf]

It definitely smears and I assume they decided against a hard glue to make repairs like mine easier. With a hard glue there would be no access to the wires.

Interesting; none of the motors I've ever worked with so far used grease like that (including either QS205).

It always requires a fair bit of work to get the cable out...but it does ensure the cable can't be pulled on from outside the motor and damage internal connections, etc.

 

[xylene23nyc]

Successfully pressed out the QS205 Axle using a 12 Ton Hydraulic shop press and a few solid steel blocks. C Clip removed.

2 of the solid steel blocks up against the axle sides and center core of the stator. Didn't put up much of a fight against 12 tons!

And now will probably cut the wire harness to pull it out of old Axle then push cable through new axle and solder cut end back together.

Once I push new Axle in (with key and c Clip from old axle) will likely seal it with some high temp silicone gasket maker.

Will update as I go along.

 

[zakiron]

I was wondering if anyone has successfully replaced a broken Axle on a Qs205 V3 Hub Motor?

Did you need a hydraulic press or was a certain sized gear puller sufficient? I have a replacement Axle on the way and could use any tips.

I am a recent victim of a nasty NYC pothole. Dual suspension won't save you here.

I'm trying to find an axle myself for the same issue. Do you have a link where you found the replacement axle?

 

[amberwolf]

QSMotors / siaecosys can provide them; you may need to know which version of QS205 you have (there are at least three), plus the shoulder widths and total length.

There's a thread in the for sale section that they monitor and reply to, and they often post links to other products there so you can follow any of those to get to their website.