5 replies to this topic

[stoneface]

Hi,

Does anyone know the clearance or size the reverse idler bush internal diameter should be?

I need to change one but can't find any info on the clearance.

Thanks.

[Spider]

I don't have any info on them either, but being what it is, a little more is better than a little too less!

I just give them 0.001" clearance, though you could likely get away with 0.0007" - 0.0008".

[stoneface]

Thanks, I've looked through everything I have and can't find any mention of the fit or even changing them.

As you say, probably not that critical.

[stoneface]

I just replaced the bush in the reverse idler with a minispares bush.

 

After boring to size I noticed the bush does not have the spiral oil way which the original had.

 

Is this the norm now?

 

Is it likely to cause an issue not having the oil groove?

 

[Spider]

I can't see it as an issue.

The Oil Level comes roughly 1/2 way up the gear (and shaft / bush) and seriously, how far in one bite would you think you'd be reversing up and how fast ?

 

You could if you wanted, set the Lathe on it's slowest speed they wind the boring bar through it at a quick pace to cut a spiral. I've done this many times and it's surprising how good you can do it. Have a couple of dry runs. Mount a bar of tube in the chuck and a felt tip marker in the tool holder, then do a few externally and see how you go. Regardless, it doesn't need to be neat, so don't loose sleep over it.

[stoneface]

Cheers,

I'll have a practice run on the lathe and see how confident I am to free hand a goove.