Adjusting a machinists level?

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scattermaster

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Hello,
I just got a PM1236 lathe and now I want get it leveled.
I bought an Accucize Master Precision Level, number S908-C687 from Amazon. It was not calibrated out of the box.
It has instructions for adjusting it but it looks like they are a very bad translation from another language maybe...
Anyway the instructions don't make any sense to me.
A tool was included with the level. It looks like a tiny hook spanner. I don't see anything on the level to use it on.
There are 2 slot head screws. One on top and one on the bottom. They seem to be be pushing on something inside but it doesn't change the bubble position.
Any Ideas out there?
thx,
Jim
Edit,
I got brave and just started taking it apart. Bingo,
Now it all makes sense. I just wish the instructions would have been better. Even just a picture would have been enough.
Oh well.
Now I can go level my level and then finish leveling my lathe. :)
 
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Please let us know how the Accusize works out for you. The price is right on these vs american precision bubble levels, but would like to know if they are useful.
 
I have a 8" Chinese level that says .0005" per 10" resolution. It checks out at those numbers, but is somewhat fussy to calibrate, and at that resolution it takes patience and care to get good results. It works, and gets the job done. I paid about $80 for it new. They have ones like it and also many others on eBay. Be sure to understand how levels work, and how they are calibrated and zeroed.. Length does not give you accuracy, names like Starrett do not give you accuracy, fancy looks do not give you accuracy. You must know the resolution. Electronic levels are an even sillier game. Make sure you know very well the meanings of accuracy, resolution, and repeatability before buying any electronic level. Walk away from any electronic level that does not tell you all three numbers and the numbers are appropriate. It is very easy to get cheated by not understanding what is really being sold. There is a lot of stuff out there that might be useful for leveling your refrigerator but not much else.
 
So... I bought an offshore 8" machinists level, which was way off calibration. The calibration screw was blue Loctited frozen and after much effort, I never did get it calibrated.

Just bought a Moore and Wright 12" engineers level, off kijiji for 45$ it is perfectly calibrated, ans is wear, scratch and abuse free. lesson learned.
 
The level that I'd like to have is a Pratt-Whitney. Hard to find in good condition and expensive.
 
From what I remember, basically you need to find a relatively level surface first.
Let me first point out the method of checking a level. When placed on a level surface the level bubble will be centered.
Now, you will rotate the level 180 degrees. It should still be centered.
If the bubble isn’t centered, I’m guessing you can take it from there and move your adjustment in order to have the bubble centered. You can also use a shim gauge to make a “level test surface “
The main key is the rotation of the level 180 degrees and the bubble still in the same place.
Check out the “calibration “ segment from wiki.
https://en.m.wikipedia.org/wiki/Spirit_level
 
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Find a flat and reasonably level surface, a surface plate is ideal, but any smooth surface you can make a mark on with pencil or chalk will do. place the level in the centre of the surface, allow time for the bubble to settle,and check the reading. If the bubble reads level you can start calibration. If it does not, begin to rotate the level 1/2" at a time, allowing the bubble to settle between moves until you find a position on the surface where it reads level. When you have it reading level, draw a line on the surface down the edge of the level, and mark the position of the ends. now rotate the level 180 degrees, and put it back against the marked position on the surface, if it reads level, you are good to go! If not, adjust the bubble to remove HALF the error, rotate 180 deg and check again. Continue until the reading is exactly the same when swapped end for end, and you have it! This method assumes your level is somewhat close to being correct, if it is a country mile out, you may have to repeat the whole process a few times to home in on the dead nuts setting. hope this helps!
 
Unfortunately I don't have anything that I can trust to be level. Soooo,
I"m forced to use my unlevel lathe. First I leveled the lathe without tampering with the level adjustment.
Then, adjust and go back and work on the lathe again, then back to the level...(repeat)
Kinda sneaking up on it. I think I have it pretty close now.
One bad thing, If I move the level to different places on the ways the readings change. A LOT.
I haven't stoned the ways but there are no visible burrs. I only wiped them off with a clean rag. Before I pass too much judgment I'll try stoning them but right now it seems like the ways are not ground straight enough to make the level happy. (China...)
 
IHMO you bought a level that is WAY too sensitive for doing a lathe. It’s a good idea to have a lathe perpendicular to gravity (level) but not necessary in most shops. Getting the twist out of the bed thought is very important. With that level you have you will pull your hair out trying to find out what’s level and not level. I would get another level not so sensitive. And then when setting up your lathe pay very close attention to bed twist. Even the Starrett master level is 0.0005”/ft and that can be hair pulling!…Dave
 
Yeah, I didn't know when I bought it. I just thought I needed a "machinists level". After playing with it last night I can see what you're talking about.
It's so sensitive I can see flaws in the ways.
I'll have to see how it goes for now. I'm kinda Waaaaay over budget already. :)
 
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