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Author Topic: Prop Shaft  (Read 2247 times)

rickles23

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Prop Shaft
« on: July 31, 2015, 09:31:27 am »
Hi,

I have just cut down the brass tube and now one of the push in bearings will not go in.

The inside of the tube is smooth as I use a Dremel to ensure smoothness.

Both bearings fit on one end of the tube.

Does anyone know if the ends of the tube are heated first and then the bearings are pushed in and the tube left to cool?

Regards
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sparkey

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Re: Prop Shaft
« Reply #1 on: July 31, 2015, 09:36:31 am »
Very likely,I used this method when I make new bearings for my prop shalfs,Ray
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Brian60

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Re: Prop Shaft
« Reply #2 on: July 31, 2015, 09:57:04 am »
Excessive heating of the brass tube will soften it and it may distort when you try and push the bearing in. Best way to tackle it would be put the bearings in the freezer for an hour or two, the metal will shrink slightly. Then warm the the brass tubing quickly, waft it in and out of a blowlamp (gas cooker/hob is a good stand in!) flame a couple of times then quickly bring the two together. Doing both actions is more likely to result in success.
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boatmadman

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Re: Prop Shaft
« Reply #3 on: July 31, 2015, 10:29:34 am »
I think you have probably got a little burr on inside of the shaft.  It doesn't take much.
I doubt manufacturers will heat the tube before fitting the bush...extra cost!
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david48

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Re: Prop Shaft
« Reply #4 on: July 31, 2015, 11:12:17 am »
Have you checked for roundness if you cut it in a vice it could be crushed to a slight oval , if it was cut with a tube cutter and it was screwed up to tight to make the cut this could knock it out of round. Is it a bearing or a bush you are trying to fit , check OD with a Mike or vernier gauge .
David
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rickles23

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Re: Prop Shaft
« Reply #5 on: July 31, 2015, 03:53:39 pm »
Hi all,

I cut the tube with my Dremel but I had another thicker tube inside it to give it support.

I then de-burred and checked the end of the tube.

But then I got to thinking and measured the inside diameter of the tube at both ends which showed that the tube itself is thicker at one end.

Yes it was the end I was trying to put the bearing in.

So I must make a visit to the store and pick up some more tube.

Thank you all for your prompt replies.

Regards
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