Bosun compass with large bubble in it............

Cliveshep

Cliveshep

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clearly needs re-filling. My questions are (1) where do I fill it and how as it is in a solid bowl with side trunions for the gimball and the only moveable bit is the graduation ring and I don't know if I took that off I would find a fill point, and (2) what do I re-fill it with assuming someone can point me to a fill point? Once I get rid of the large bubble it is unlikely to leak again as it is always in the upright position. BTW it is 2nd hand and I've had it many years and it is a faithful bit of kit.
 
Massive forum discussion in the past about fluids to fill compasses. The conclusion when I asked was use White Spirit. I did this several years ago and it has worked fine ever since. (Drained off all the old stuff and re-filled). Inexpensive and very effective solution to this problem.
Martin
 
Carefully remove the two plasic screws, one either side, and you can lift the compass from the bowl.
(In fact its not necessary to competely remove the screws, unscrewing them about 1/4" is enough)

The filler is obvious.

BUT get the correct fluid from a compass repairer. Eg Sirs navigation. Someone will remind us of the forum user who is a compass repairer as well.

I'd guess at white spirit but use the wrong fluid and you could wreck it.

It may be more sensible to get it filled by a repairer.

I have had mine from new (ca 1978)


If you can get a laboratory test tube (everyone has a rack of test tubes anyway dont they) Put some white spirit in it. Add one or two drops from the compass. if you cannot see the two as they mix it means they have the same refractive index and are very likely to be the same. If you can see the two as they mix or if they dont they they are not the same!
 
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but I can't see anywhere to introduce the fluid so that is still my puzzling question.

[/ QUOTE ] Not read my post then! Wont bother to take something apart specially again /forums/images/graemlins/wink.gif
 
What no-one has said so far is that if it has a big bubble it's probably got a leak. You need to fix the leak before refilling. Might be worth taking it to a compass repairer.
 
Oh God, sorry VicS, didn't mean to be rude, I was answering the previous post whilst you were posting yours and I didn't see it. I'm going to study what you have said carefully and if I can get a sniff of what's inside I might be able to take a fair guess as to what it is although the earlier post suggested a consensus on a previous forum thread of using white spirit.

PVB - I think the leak was caused by the thing upside down in a locker in France for yonks with it's previous owner. I got the thing off E-bay ages ago for the princely sum of £9.99 plus postage across the ditch so it was a bargain. It probably leaked through the trunnion pin, but I'm now going to study VicS' post to get a better handle on it.
 
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It probably leaked through the trunnion pin,

[/ QUOTE ] No, all the gimballing stays with the bowl, The compass unit lifts out with just the bezel It appears to be just clipped into that.

PVB may well right, he sometimes is /forums/images/graemlins/grin.gif , but its worth investigating.

Its a big brass(?) capsule in there with a bottom that looks as though it flexes to take up expansion and contraction.
Take it apart, all will be revealed.

This is the second time I've taken mine apart to answer a question on here. I think I'll photograph it all this time.
 
Sunlight and heat are the killers of a compass. The heat building up pressure and vapourising the fluid until it leaks out.

It needs to have a cover over it at all times except when being used. olewill
 
Not necessarily white spirit, the plastimo contest compass smelt of what bseemed like baby oil, so I topped mine up with Johnsons Baby oil from the chemist, (where I also got a cheap pipette), several years ago after I fixed the leak.
White spirit is volatile so it will try to evaporate in the compass in the heat, not so the baby oil.
White spirit is so thin it would have no damping and may even lift the legend off the float.

Both are cheap, but smell it before you commit, they may not mix well if you have the wrong one
 
Plastimo compasses used to use an oil from the Esso Bayol range but it is no longer available. Another forumite successfully topped up a Plastimo compass with ordinary paraffin
Baby oil is just one of those liquids from a long list which might be suitable.

The only sound advice that can be given is to obtain the correct oil from a compass repairer
 
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My memory is going

[/ QUOTE ] Read Second Affaire's post above!

Actionoptics repair

surprise surprise

Binoculars and telescopes /forums/images/graemlins/grin.gif
 
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Plastimo compasses used to use an oil from the Esso Bayol range but it is no longer available.

[/ QUOTE ]
Bayol is still available from Sirs Navigation, but may not be the correct variant for Plastimo compasses.
 
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