What could I possibly be doing wrong?

As mentioned, it's not unheard of for charts to be wrong. This may help:

littlemachineshop.com

Change Gears for Threading

This calculator determines the correct change gears for any thread pitch. Works for all mini lathes and HiTorque Bench Lathes.
littlemachineshop.com littlemachineshop.com

It's well worth investing a little time in truly understanding it all from first principals, though, then the calculators (or indeed charts) are much easier to use and understand.

Hope you're happily threading the correct pitch soon!
 
Papa Charlie said:
CII is for .125 for 1.25 it is CIII according to the label. It also calls out a 70/56 gear tooth which all seem to be correct along with your settings.

@Oliver19619 Are you engaging the lead screw at the 8 mark? That appears to be the only mark that you can use for this pitch.

Not sure what the difference is between the 40T and the 45T Scale it is referring to. Appears that one of the gears has to be a 45 tooth. Not sure but the only gear shown in your gear set that comes close is the one marked 40, you may have to change that gear for a 45 tooth.
Click to expand...
Hi there papa Charlie, I will upload some more clear photos of the gears/dial indicator. The first few are the dial indicator so you can raise and lower it for the tooth count on dial. Okay so as for the gear train, the main spindle is 40t the one attached to Chuck etc, then there’s 3 gears interlinked that I don’t believe can be altered because they’re kind of fixed on the lead screw direction knob, so if I were to put a 30t cog it wouldn’t reach the other two gears responsible for reversing the lead screw. The position of the 40t cog pictured can not be altered. As for engaging the dial on 8. Would that make a difference on the pitch? I thought that was just for engaging at the same point to catch previous thread? Thanks for all of your recommendations/help.
 

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Oliver19619 said:
Hi there papa Charlie, I will upload some more clear photos of the gears/dial indicator. The first few are the dial indicator so you can raise and lower it for the tooth count on dial. Okay so as for the gear train, the main spindle is 40t the one attached to Chuck etc, then there’s 3 gears interlinked that I don’t believe can be altered because they’re kind of fixed on the lead screw direction knob, so if I were to put a 30t cog it wouldn’t reach the other two gears responsible for reversing the lead screw. The position of the 40t cog pictured can not be altered. As for engaging the dial on 8. Would that make a difference on the pitch? I thought that was just for engaging at the same point to catch previous thread? Thanks for all of your recommendations/help.
Click to expand...
Just had a little mess about where I engage the lead screw has no difference on the readings of final travel of carriage. I just don’t understand it.. if i were to leave the gears set under cover and change the knobs on the front to A + 3 for example I get a 1mm pitch exactly. Strange one.
 
Papa Charlie said:
CII is for .125 for 1.25 it is CIII according to the label. It also calls out a 70/56 gear tooth which all seem to be correct along with your settings.

@Oliver19619 Are you engaging the lead screw at the 8 mark? That appears to be the only mark that you can use for this pitch.

Not sure what the difference is between the 40T and the 45T Scale it is referring to. Appears that one of the gears has to be a 45 tooth. Not sure but the only gear shown in your gear set that comes close is the one marked 40, you may have to change that gear for a 45 tooth.
Click to expand...
Okay I removed the pulley spindle etc so I could get this..There is a photo of the whole gear train
 

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Okay so the gearing from the the ratiois 1:1 followed by the gearing 30-100-70-56 so I’m under the impression that the only gears to be changed are the bottom 4. Which is what I have done..set the turn knobs still to the required settings, so I can use this gear setup to get a pitch of 1.0mm as the diagram says. But not 1.25mm strange one it really is.
 
Okay thank you all so much for your help I swapped out the 56 tooth gear for a 63 and the jobs a good’un bloomin charts.. honestly I can’t thank you all enough for your suggestions etc.
 
not too sure if the threads are deleted after a certain time but for reference..if anyone ever had the same problem with lathe, the gear train runs 40t spindle/ 30/96/70/63 gears and the same knobs to correct the pitches 0.7mm-1.25mm-1.75mm.
 
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Oliver19619 said:
not too sure if the threads are deleted after a certain time but for reference..if anyone ever had the same problem with lathe, the gear train runs 40t spindle/ 30/92/70/63 gears and the same knobs to correct the pitches 0.7mm-1.25mm-1.75mm.
Click to expand...

I've been following along. I didn't make any suggestions because I didn't have any better opinions to offer.

Good to see you sorted it out.

However, now I'm confused. What happened to the 100 tooth gear indicated on the chart?
Did you count the teeth and only found 92 (another chart error?)?
Is 92 a typo? please elucidate.
 
I'm interested too- what possessed you to swap the 56 tooth gear for the 63? Intuition? Wild guess?
Also wondering about the 92 tooth, where did he come from?
-Mark
 
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