Mellor lathe.

[God mode restorations]

I trying to figure out where B and A are on the lathe

 

[Ian James]

From that diagram it looks like B is running as a compound gear to c ie pinned to gether on the same stud so changing the ratio

 

[God mode restorations]

Have sussed it out now....
Am still missing a few gears but I understand where they go now in relation to the chart.
I set the machine up to do 28 tpi. Just as a test. I haven't cut any .Just marked it with a pencil. And there are 28 threads an inch.

 

[zx9]

Get a couple of bits of scrap and make a 28tpi internal and external thread, see if they will screw together, it will be a good learning exercise.

 

[God mode restorations]

Get a couple of bits of scrap and make a 28tpi internal and external thread, see if they will screw together, it will be a good learning exercise.

Will do soon. Am a bit stumped on something

 

[God mode restorations]

Evening guys. I been setting up my gears for testing different pitches of thread. I had a few goes just using a marker as guide. Now I got totally stumped. Trying to set up nine tpi. It reads A. Should be 40. B 55. C 40. D 90. Done that and am miles out. Am I missing something

 

[Ian James]

@spencer 427 a mile out in what way high or low ??

 

[God mode restorations]

@spencer 427 a mile in what way high or low ??

The tread is fine.

 

[zx9]

I would have read that as 40 on the spindle and 90 on the lead shaft (with two identical gears on C and D )

 

[Ian James]

So what's a mile out spencer

 

[Ton-up]

The way I would read that is that you do not use gears B and C.

 

[zx9]

The way I would read that is that you do not use gears B and C.

Except you would need them else the lead screw would be going backwards, hens the two identical gears on B and C.

 

[Ian James]

But if gears A and D don't mesh with each other you will need a compound set in that does not change the ratio and zx9spost above I have done that my self then scratched my head for a minute wondering why

 

[Pete.]

Evening guys. I been setting up my gears for testing different pitches of thread. I had a few goes just using a marker as guide. Now I got totally stumped. Trying to set up nine tpi. It reads A. Should be 40. B 55. C 40. D 90. Done that and am miles out. Am I missing something View attachment 141182

Yes. 9TPI is 40 on the spindle A and 90 on the leadscrew D. You don't use the compound B and C though you might need gear B as an idler to fill the gap. It doesn't matter how many teeth are on it.

 

[Pete.]

Except you would need them else the lead screw would be going backwards, hens the two identical gears on B and C.

It would if he didn't have the tumbler reverse. With that he can just reverse the screw and the gearing isn't affected.

 

[zx9]

Except you would need them else the lead screw would be going backwards, hens the two identical gears on B and C.

I was assuming perhaps wrongly that the lathe does not have a tumble reverse.

Cross posted with @Pete.

 

[God mode restorations]

Yes. 9TPI is 40 on the spindle A and 90 on the leadscrew D. You don't use the compound B and C though you might need gear B as an idler to fill the gap. It doesn't matter how many teeth are on it.

Ar got ya now. Thanks pete

 

[God mode restorations]

Got it sussed now guys. Thanks for the help everyone .very appreciated.

 

[God mode restorations]

Today's task is to carry on cleaning and oiling the rest of the change wheels. Boring but needs doing.

 

[MattF]

I found that thinners which they occasionally sell at Lidl works awfully well at lifting paint, if you leave them to soak in it. It's only around £2.50 per litre. That's how I cleaned up all of my changewheels. Soaked in kerosene first if they were oily/greasy, and then soaked in the thinners to remove the paint.