Spark plug
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Get a tray of water big enough to fit the level in, put it in the freezer, wait for it to freeze, then without moving the tray you should have a flat surface.
So the easy way is to get a wooden batton and fix a tube to it and fill with water. The water will level itself. Then you have a reference. Get that level and you are done.
If you are up in Perth I have an engineers level, surface plate, some bars and gauge blocks we can sort it out.
LOL. So basically, you’re suggesting he should make another spirit level!
Personally I don’t think he deserves one...
I think we're getting somewhere! If you set it on a "known" 30 degree slope then accidentally hit calibrate, it will call that angle zero. Are you with me?
Now when you turn it through 180 degrees and put it back on the same slope, it will read 60 degrees (or 300 depending on your model of level). DO NOT TURN IT UPSIDE DOWN!
So let's pretend you can stuff a wedge under that 30 degree thing, you want to wedge it by half the error being displayed which in this case we happen to know is half of 60 i.e. the 30 degrees you want to remove to give yourself a calibrated level surface. In general though, even if you don't know what the error angle is when it is reading zero, just turn it 180 and wedge up the surface until you remove half the reading, then hit calibrate, then turn it again, and again, and again...
Just take it back to shop... Get a replacement.By jove, I think you've got it! Probably best not to use a scribe or permanent marker, but that definitely sounds like a plan
I can't believe this thread is still going or that people are still suggesting you introduce a secondary level to measure it against.
Using water to measure a "level" is all well and good but you then have to transfer that measurement to calibrate the equipment under review. That will lead to inaccuracy. You can't use a flat water plane to support a spirit level or laser level during calibration (freezing which I think** was a joke, doesn't work because water does not expand uniformly as it freezes) so you would have to use that setup to calibrate a surface by eye. Water level in a tube forms a meniscus which deforms the surface meaning you have to average it out by eye. Fine when you're building a house and measuring greater distances but at smaller scales (remembering you are setting up a surface) the errors introduced when the "level" is read off can be huge. That is why a "spirit" level is so-called, they use spirits, typically a very thin oil which does not form a meniscus or suffer from friction at the tube interface.
Even if you did manage to create a "perfectly" flat surface, you still have to place the unit under test on it and it still might not register a perfect level due to inaccuracies in the unit itself. Those built in errors still need to be dialled out by taking two measurements and adjusting the unit itself until it gives you a zero in both orientations. Typically with a lit. sprit level, you mechanically adjust the bubble chamber with respect to the body of the unit and specifically wrt the base. An electronic device will perform that adjustment by introducing an offset in the readout.
With both sprit based and electronic detectors, the theoretical precision of the measurement process is much higher than any water based system, otherwise why not just use water in the first place.
A spirit level or laser level is self calibrating. The most accurate way to set the level is to use it to measure its own reading until it registers a zero in both orientations along a line set up on a surface as described above (many times now). It will then give you a reading which corresponds to the ultimate accuracy of that particular level.
Can we move on to "set squares" now? They are another self calibrating measurement system....
That's exactly the point, it will be very very accurate over large distances. No good for very short distances though.I used to use a water level often in the boatshop for setting boats up for build or restoration, long bit of clear pipe, water & some food dye if you were feeling rich. Over thirty feet it was as accurate as i needed it.
I used to use a water level often in the boatshop for setting boats up for build or restoration, long bit of clear pipe, water & some food dye if you were feeling rich. Over thirty feet it was as accurate as i needed it.
Well, I've learned loads from this thread so I'm happyI can't believe this thread is still going or that people are still suggesting you introduce a secondary level to measure it against...
That's exactly the point, it will be very very accurate over large distances. No good for very short distances though.
Well, I've learned loads from this thread so I'm happy