Logan Lathe Back Gear Troubles .....

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I have a new replacement 28 tooth back gear to replace one with a broken tooth. Head stock is disassembled and I've reached the point for removing the old gear and installing the new piece. Problem - the old gear will not come free of the shaft. Plan view drawings of the assembly show the gear installed against a shoulder on the shaft and held in place with a woodruff key. I see no reason why a gear would have been pressed on such an assembly but I've been wrong before so I may not fully understand the assembly process. Regardless of that fact, capturing the shaft with the gear against resistance and using a soft mallet on the end of the shaft has proven unsuccessful. I am not convinced that heating the assembly is a good idea because the shaft contains a bronze bushing - would not want to damage that.
I don't own a hydraulic press. Anyone have an idea????

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I wouldn't worry too much about heating the assembly (moderately) but I would caution against trying to pound it apart- maybe this
would be a good time to mosey on down to Harbor Fright and invest in a press? Or find someone who has one? It's really the way to go.
Mark
 
I agree with Mark that a press is the best way to go - either hydraulic or arbor. If that's absolutely not an option, you might be able to use a bearing puller. You would need to put something on the end of the shaft for the puller screw to bear on.
 
Putting it back on is easy, it's hollow. Some fine thread allthread couple of washers and nuts good to go. Once you have the old gear off now you can control the amount of interference of the two pieces, dope it up with white lead or always seize, get it started straight and pull it on. I wouldn't polish the shaft down to reduce the fit but buff out the gear if needed as it becomes a sacrificial part if you screw up. I have used a bottle jack a few times as well.
 
I was confident that I'd get some good ideas and I'm grateful for all the suggestions.
I liked the idea of turning it off but I'd have to re-install the headstock then remove it again so I elected to try another suggestion.
After recently "down sizing" and having to surrender a lot of my former shop tools I had to dig down deep into the boxes of things I was able to bring with me and as luck would have it I found a puller.
Problem solved,. Installing the new gear with an arbor press put me back in business.
Thanks to all ......

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