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Darn it ....a tripod head bolt is magnetised !!!!

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#1 Ian Robinson

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Posted 10 August 2009 - 03:25 AM

Noticed one of tripod leg bolts on my CG5 is slightly magnetised (I've a non-Celestron steel tube type tripod that I bought on Ebay came with this problem I think) , puts my compass alignments off a bit unless I offset the compass from the tripod head by about 12" or more my 1m spirit level bar.

Anyone know how to easily degauss a bolt ? I'd rather keep the tripod assembled .

#2 John Carruthers

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Posted 10 August 2009 - 05:37 AM

I'd just replace the bolt, but any ferrous material will affect your compass.

#3 wasyoungonce

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Posted 10 August 2009 - 06:34 AM

It's just the iron in the bolt localising magnetic flux line causing the compass to deviate. It's probably not magnetised, although you can test this (the bolt) with some paper clips.

Any iron source near a compass will upset magnetic flux lines. Most tripods have steel bolts & thus compasses are affected by them.

Try to move the compass as far away as possible, lets say on a wooden board across the legs base?

#4 TONGKW

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Posted 10 August 2009 - 07:28 AM

You can replace the existing bolt with one made of AISI 304 stainless steel which is non-magnetic. Try the bolt with a magnet when you buy it.

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#5 Cyclop_si

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Posted 10 August 2009 - 07:38 AM

...steel tube type tripod ...


Even if you exchange megnetic bolt, your compas is going to be affected by steel tripod...

Just go some 10 meters away from tripod with your compas and check directions there.

#6 Luigi

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Posted 10 August 2009 - 07:43 AM

I hand hold the compass about 3 feet from the mount when using it to polar align to avoid affects from steel, motors, and their magnets, etc..

#7 Ian Robinson

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Posted 10 August 2009 - 08:39 AM

I hand hold the compass about 3 feet from the mount when using it to polar align to avoid affects from steel, motors, and their magnets, etc..


I don't put the head onto the tripod until it's leveled and then compass aligned . It sits at least 8 ft away in the back of the Pajero or on a work bench in the garage until the above is done, I then bring it out and line it up with chisel mark on the tripod head.

I've some spare leg bolts that might be the right length from another older tripod that I spotted in my tools cabinet , I'll try them out (with the magnet first if they look the right size).

The other leg bolts don't seem to effect the compass needle , just one of them .
I think the legs are stainless steel (well that's what I was told they were when I bought it) and I haven't noticed any deflection due to the legs when I hold the compass right next to them).
I was also under the impression the tripod bolts were supposed to be srainless as opposed to ordinary Cr steel which has been chrome coated. I may be wrong on that score.

#8 Wes James

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Posted 10 August 2009 - 09:14 AM

Tong's correct, stainless hardware is non-magnetic... depending on the grade. Some grades still can be a bit magnetic. A good way to de-magnetize/degauss a magnetic part is with a soldering gun (not iron). Turn the gun on away from the part- bring it next to the component, and make circular motions down the length of it- then moving it away in the opposite direction before turning the gun off.

#9 Billydee

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Posted 10 August 2009 - 12:52 PM

If you have an old TV repair shop near you (25 years old or more). They will probably have a demagnetiser for correcting the old TV screens. Take your bolts and have them passed through the loop when it it plugged in. When the items are in the AC field they are demagnertised (only takes seconds). They usually will do it for free if you are nice to them.






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