1957 Logan lathe gear defect - Keep or Replace..?

[RandyM]

I say keep it, install it, and don't fret over it for another minute. The gear is obviously made from a casting and you are going to get things like this when they are machined. The part passed Logan QA because it is not defective. It is only an appearance issue and not a functional one.

 

[682bear]

I say keep it, install it, and don't fret over it for another minute. The gear is obviously made from a casting and you are going to get things like this when they are machined. The part passed Logan QA because it is not defective. It is only an appearance issue and not a functional one.

I agree... as long as the hole is concentric with the outer diameter, you are unlikely to ever have any problems with it.

There was apparently a certain amount of core shift during the casting process... that is fairly common in most casting processes, but does not necessarily mean that it was a defective part.

-Bear

 

[682bear]

For example... this is the apron casting off my Logan 11"... none of the holes are centered in their cast bosses...



The casting is created with the bosses cast in an approximate location, then the holes are bored accurately... but usually are not centered in the bosses.

-Bear

 

[Uglydog]

Mr Mike,
If any of these might be helpful then please PM me.
I think they all fit a Logan. But we would want to check DP, ID shaft size, and tooth count on the other gears.
One is shop made, one has a broken tooth, all the remaining appear unused.
I'd be most interested in moving them as a lot. I likely have others here .... somewhere....

Daryl
MN

 

[Mr Mike]

Just curious - is the central hole centered within the circumference of the rim?

No it's not... I chucked it in the drill press and its on the money with the circumference of the teeth. no wobble what so ever. I did put it in a hand drill full speed and there is a minor imbalance.

 

[mikey]

No it's not... I chucked it in the drill press and its on the money with the circumference of the teeth. no wobble what so ever. I did put it in a hand drill full speed and there is a minor imbalance.

As long as the degree of off-centeredness can be accommodated by the clearance between gear teeth then it should be okay to use.

 

[Mr Mike]

Mr Mike,
If any of these might be helpful then please PM me.
I think they all fit a Logan. But we would want to check DP, ID shaft size, and tooth count on the other gears.
One is shop made, one has a broken tooth, all the remaining appear unused.
I'd be most interested in moving them as a lot. I likely have others here .... somewhere....

Daryl
MN

Hello Uglydog, Thanks ever so much for offering. I think I'm good on gears but ill hit you up if things go south.. Thanks man.

 

[Mr Mike]

I say keep it, install it, and don't fret over it for another minute. The gear is obviously made from a casting and you are going to get things like this when they are machined. The part passed Logan QA because it is not defective. It is only an appearance issue and not a functional one.

I believe you are spot on man.. Thanks.

 

[Mr Mike]

I agree... as long as the hole is concentric with the outer diameter, you are unlikely to ever have any problems with it.

There was apparently a certain amount of core shift during the casting process... that is fairly common in most casting processes, but does not necessarily mean that it was a defective part.

-Bear

Hello 682bear, thanks for the input... Ya its dead on with the teeth.! Ill be keeping it, adds character to my lathe. Thanks Mike.

 

[Mr Mike]

I guess another way of looking at this that you don't need to make a decision now. After you get the machine running,
try running with and without the gear. If you detect vibration that you find objectionable, you can change the gear then. If not , you are aren't out 150 bucks.

Hi Nogoingback.. Ya its a keeper - I checked it in a drill press and hand drill - its got a small weight imbalance but rotated perfectly fine and centered - its a keeper, Thanks Mike.