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Novel rear axle bearing removal idea went south

Old Jun 24, 2020 | 10:37 PM
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Novel rear axle bearing removal idea went south

As you can see from the two videos I used induction to remove both the shaft collars and bearings. In order to get the induction coil around the bearing (and to not ignite a whole lot of grease) I removed the outer race with a grinder. On one of the axles the grinder got away from me and I gashed the axle right where the shaft collar would go.

Does anyone think it is a bad idea to use this axle? If the gash wasn't on the surface of an interference fit part that is holding the entire axle on the car I wouldn't think twice. Oh and I plan on throwing 350whp at it.




Last edited by Chris79SA; Jun 24, 2020 at 11:52 PM.
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Old Jun 25, 2020 | 05:42 AM
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I would have no issues using the axle. I would smooth the gash out and press your bearing and lock collar on. You will not have any issues from that.
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Old Jun 25, 2020 | 11:00 AM
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Describe what your are doing with that induction setup? I assume its filament that heats up and looks like its connected to a welder box?
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Old Jun 25, 2020 | 11:24 AM
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Originally Posted by t_g_farrell
Describe what your are doing with that induction setup? I assume its filament that heats up and looks like its connected to a welder box?
No it's an induction "furnace". It's a form of non contact heating. It works on anything that conducts electricity. A massive amount of current at low voltage flows at through a resonant tank circuit. You can think of the copper coil (water cooled) as the primary of a transformer and the workpiece (the axle) as a shorted secondary. Think about what happens when you draw too much current from a transformer. The core heats up. There is also something called the skin effect at high frequency. It heats from the surface inward as it conducts, so in a slow conducting material like steel, the bearing falls off due to thermal expansion before the axle gets real hot.

Here is a video that demonstrates it more clearly.
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