Lathe setup question

[oogenshire]

Spent what feels like forever leveling out my lathe today ( they keep moving the floor lower every year) turned a quick 60 degree point on some stock since i dont have a mt5 dead center yet and used my edge tech alignment bar to dial in the tailstock. Ran a cut down 4 inches of stock and meaused it out like the manual states. Im .84mm smaller on the far side from my chuck than i am on the chuck end. Should i adjust headstock alignment at this point, or go back to leveling it out and see if i am off a bit?

 

[Huub Buis]

To find out if your lathe bed is not twisted and your head stock is aligned, you should turn a bar without tail stock support. Once your lathe is leveled, you can adjust the tail stock.
To turn a long straight bar without tails stock support, you need to reduce the cutting forces. So take a very light cut at a very modest rate or use the Rollie's dad's method.
You can just turn a bar and do some measuring and calculate the alignment

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[oogenshire]

Ok so here is what ive got copying whats in the video. Next step would be to put indicator on end of stock and adjust out the .48 mm? Then do the test again correct? Instructions in manual are a little vague

 

[Huub Buis]

Don't remove the bar from the chuck, just align the lathe. After aligning, you don't need to turn the bar again. You can check the alignment using the same bar and only use the indicator to measure again.
If your lathe has only a foot rest at the head stock and tail stock, like most bench top lathes, you can start by loosing the bolts. Most of the time, the alignment is OK because the lathe bed was machined after the food rests where machined.

 

[ddickey]

Use large diameter 6061 aluminum if you can and a super sharp hss bit with lots of back and side rake. .001" cuts.

 

[oogenshire]

Don't remove the bar from the chuck, just align the lathe. After aligning, you don't need to turn the bar again. You can check the alignment using the same bar and only use the indicator to measure again.
If your lathe has only a foot rest at the head stock and tail stock, like most bench top lathes, you can start by loosing the bolts. Most of the time, the alignment is OK because the lathe bed was machined after the food rests where machined.

bar is still in chuck, this is a jet 1440 according to the manual its 4 cap screws and an adjustment block on the far side of the tail stock from the chuck. my current plan is to pre load indicator the required amount (.48mm) and adjust to zero, hopefully lol judging by the leveling feet on it its going to take a while

 

[Huub Buis]

It seems your jet 1440 is quite a heavy lathe.
Once the lathe is leveled and the head stock is aligned, aligning the tail stock will be a lot easier and you can use the dial indicator to move the tail stock the appropriate distance.
The tail stock alignments of my Chinese lathes was pretty bad in X and they where also angled in 2 directions. It took half a day (manual) grinding to get it straight. Once setup, I keep the tail stock alignment as is. Long bars I turn CNC and use the software to correct for head stock / tail stock misalignment's. Even so, proper tail stock alignment is still needed for drilling holes using the tail stock.