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Wedge Bubble Level vs. external level

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#1 Jim W. Coleman

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Posted 12 July 2013 - 02:50 PM

Greetings,

I was frustrated last night when working on alignment to find that the level built into my Meade wedge does not agree with an external bubble level I placed onto the flat base of the wedge. Not even close. And that external bubble level does not agree with the short torpedo level I placed across the platform on my pier, which the wedge is bolted to. Which should I trust? I tell you, I was sure scratching my head looking at three levels giving different results. I did take the external bubble level and the torpedo level and placed them on my kitchen counter and they showed the same result, so thinking maybe my wedge level is no good and I should just trust a bubble level placed on the flat bottom surface of the wedge? Have you ever had issues with the built-in level on your Meade wedge?

#2 Calypte

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Posted 12 July 2013 - 03:02 PM

Does it have to be precise? You've already demonstrated that the wedge's level isn't accurate. Ignore it. Use an external level.

#3 gdd

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Posted 12 July 2013 - 04:02 PM

Adjust until level according to the external level. Then flip the external level end for end - if it still reads the same it is accurate.

Gale

#4 Footbag

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Posted 12 July 2013 - 04:11 PM

Always test your level. A lot of them are not level, I test every level I buy and go through more then you would expect before finding a good one.

I once walked out of Harbor Freight with 6 levels. They cost me $4 total. I joked with a friend wondering how they could build them for that price. Sure enough, 3 of them were not useable.

Test levels by putting it on a surface and noting where the bubble is. Then turn it around and the bubble should be in the exact same spot. If it's not, find a new level.

#5 Jim W. Coleman

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Posted 12 July 2013 - 06:24 PM

Okay, I went to Lowe's and bought three levels. I think I'm on the right track. My confusion was in that all the documentation I keep reading says to "level according to the bubble level in the wedge." But that level is obviously wrong so I didn't know what to do. I now have an external bubble level on the wedge and also levelled across the fork arms and across the top of the OTA with it pointed straight up. Everything appears to be in order. I also read somewhere that I could take a hammer and chisel and 'pop' the wedge bubble off and replace it with another. May do that for future, but may just upgrade the wedge. Sure do miss my Ultrawedge ... never had a problem with that one. This is the Meade cheapie wedge ($150) that I had to get in a hurry when I sold the last scope and my nice wedge ... Hindsight ...

#6 SkipW

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Posted 12 July 2013 - 08:09 PM

Why does it matter if the base is precisely leveled? As long as the polar axis is aligned with the pole, the orientation of the base doesn't matter.

#7 rdandrea

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Posted 13 July 2013 - 12:24 PM

I think the guy who built our house in the '50s had one of those defective levels. Nothing is square or plumb. NOTHING.

#8 gdd

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Posted 13 July 2013 - 06:44 PM

As long as the polar axis is roughly aligned with the pole when you check for levelness, you will be consistant from one session to the next even with an inaccurate level. Consistancy is what you are really after.

Gale

#9 frolinmod

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Posted 13 July 2013 - 11:28 PM

When the base of a GEM mount is not level, adjustments to the azimuth axis can have an affect on the altitude axis and vice-versa, making the adjustment process less intuitive, less straight forward and more time consuming. A level mount removes or at least minimizes that extra added complication. I find removing extra complications makes my lazy (expletive deleted) life that much easier.






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