Dipping my toes into turning

Excellent points, @Jim F and @Geswearf.

I did my first cut, just because I couldn't stand the wait, and have lots of questions. But let's take things in order. Have aligned ("leveled") the lathe. I watched Blondiehacks' and TOT's videos on taking the twist out, and just wanted to see if what I am doing is legit or not. So I used two 1-2-3 blocks and placed them on the flat ground track of the bed ("ways" maybe) near the head stock. Then adjusted the feet until the machinist level read center. Switched the block, in case they are mismatched; also flipped the level, so did 4 observations Repeated near the tail stock.

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In those videos they also cut a cylinder like a bar bell to see if the diameters at the ends agree. I am not quite ready for that, but once my tools are set up etc will do that with a 0.75" steel rod (I only have a 0-1" micrometer).

Next have to figure out a way to center the tool height. I saw on YT that people have fancy indicator-based tools, but for starts I just eyeballed it to the tail stock.

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Is there any better simple way?

Feeds and speeds.
I am familiar from milling with calculating feeds and speeds and with my mill I do not use carbide tools because of my max spindle speed of 4200; so am familiar with the 80 SFPM rate for a HSS cutter in steel. Today my first ever cut was to face a 2.75" diameter aluminum scrap, for which the RPM calculation is (2800 / 2.75) x 3.82 = 3900RPM. That seems insanely fast; obviously the lathe tops out at 2,000 but I felt uncomfortable even with that, and used 800 SFPM and 1000RPM. Even that felt fast, but the surface finish seemed good. Will check Machinery's Handbook for feed rates. LMS' calculator suggests 1000 SFPM for carbide and yields 37ipm feed rate.

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Chips seem crazy. I though you are supposed to have small comma-shaped ones:

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I have lots of questions; will also have to install the DRO properly, and learn to use it, and think about tooling storage (3D printed most likely).

Seems like the compound has a default screw position at 30degrees, and could not figure out how to tighten it at other degrees. 30 degrees will work, but I wonder if I'm missing something obvious.

The lathe is a delight to use. Feels like a quality item, tight, and smooth.

HAPPY NEW YEAR EVERYONE!
 
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Mount the DRO on the headstock and attach the the electrical cabinet with a backing plate, last thing you want to be doing is reaching over a spinning chuck. Starrett 98 is not sensitive enough for leveling.

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Centering the tool: A machinist at the local university showed me this. You take a 6" pocket scale (ruler) and hold it vertically against the workpiece. Then advance the tool until it just touches the scale and holds it in position. If the scale is tilted top away from you, the tool is high, top toward you, tool is low. When the scale is vertical you are centered. To clarify, you are placing the scale against the curved o.d. of the round workpiece. You can also use a short section of a hacksaw blade in a pinch (grind teeth flat).

Does this make sense?

Chip shape will depend on the material you are cutting.
 
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Mount the DRO on the headstock and attach the the electrical cabinet with a backing plate, last thing you want to be doing is reaching over a spinning chuck. Starrett 98 is not sensitive enough for leveling.
I recall reading that ocean going ships carried metal lathes (ok, larger vessels). Does level matter that much as long as the bed is supported evenly?

 
Congrats on your 1340. I did a lot of good work on my 12X37 before I upgraded. I still use the 12" for lots of quick things.
 
Level is relative and also depends on if you are measuring off the cross slide or ways. I prefer the latter with 123 blocks. You are only concerned with bed twist so there no need to be absolutely level, just that the reading is the same. Personally I would not spend big $ on a precision level that you may only use a few times, and the ultrasensitive one 0.0002"/8-12" are too sensitive and will drive you crazy. I usually recommend 0.0005"/8 or 10" sensitivity and no bigger than 8-10" for that size lathe. VIS is a good brand, if you to be able to find them in very good condition for $100-120, but looks like that is in the past and the we are flooded with the Chinese ones. I do not know what to recommend theses days that is decent quality (i.e. repasts well) and is reasonably priced. The Starrett 199 master precision level are way too long for this size lathe and are outrageously overpriced these days.
 
I recall reading that ocean going ships carried metal lathes (ok, larger vessels). Does level matter that much as long as the bed is supported evenly?

Yes they did, I spent most of my working life on large tankers and bulk ships, they all had lathes and some had other machines as well. Having a lathe level is a fantasy from the drawing office. Obviously on a ship the lathe will almost never be level. What is important is that the lathe, or any machine, be free of any torsional twist within its frame. The standard method of doing test cuts is the best way to check this.
 
Rotating the compound

I really need help to understand how I can rotate and lock the compound.
If I un-tighten the front screw without removing it, the compound rotates freely, but only if the rear (or right -sided) screw is removed. If the rear screw is in place (not tightened) it only travels a few degrees of rotation around 30 degrees. The rear nut is also sunken deeper, meaning the screw has to be advanced deeper to engage the thread, compared to the front (left) nut.
So if I want any angle other than 30, I can only tighten the front screw. That doesn't sound right, and I am obviously missing something. Please help, thank you.

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The T-nuts that the locking bolts thread into are binding in the circular T-slot. Take off the compound and inspect. You may need to round the corners of the T-nuts to prevent this. Others have have made replacement T-nuts that are longer and less prone to binding. You can see all this explained in this thread:

 
More discussion of the T-nut issue can be found at these links:

 
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