Binnacle bubble

[uncas]

Seems I have a small bubble in my old constelation compas....Am not sure whether I will be able to "box the compas " with the compas as is...Is it possible to do so or do I have to send it back to the factory? Or are there people out there who can add the nec. fluid to get rid of it
without having to go through taking it out, sending it off, and reinstalling it...?.

[Dan McCosh]

It does have to be removed, but the procedure for filling is pretty simple. There is a rubber bladder in the bottom that allows for expansion and contraction. You have to remove the fill plug, add a little compass oil, and then press on the bladder until the air escapes. The trick is to get the plug back in without a bubble, but it's not that hard. I have to do this most every spring, as the cold weather seems to make bubbles. Actully, it works fine with a small bubble, but it doesn't look so good.

[uncas]

Dan...that is what I am hoping...The fill is there...but I heard a rumor that I may have to send it back to the factory...Was not overly excited to do this...
I have heard horror stories...especially with a brass mounted one...A friend had his conveniently disappear at the factory...The factory sent him a new one...with plastic mounts. He screamed...and for whatever reason, the factory conveniently found his..( took about 8 months )So did not want to send it back.
Thanks
jamj

[JimConlin]

My Constellation developed a 1" bubble in very cool weather. I was told that it did not affect function. The fix is to add a bit of fluid, but I can't remember what the fluid was. A good resource on these is Robert White Instruments in Boston.

[Noah]

Depending on what fluid you have in the compass, it will expand and contract with heat. Throw the compass into the fridge or freezer for a bit along with the fluid, then fill it when cold. As it heats up the bubbles will disappear.

Good luck, I went through this last spring with my Kelvin and White bronze compass.

Noah

[Dan McCosh]

There are usually a few compass repair guys around that could also do the job. I don't know who is doing it today around here, but they seem to be retired guys with neat shops and great stories. To them, it's hardly even a job, just the last step in putting the compass back together.

[uncas]

Noah as you and I have the same vintage boat and maker...I suspect that as mine is close to being original...the stuff in the binnacle is identical to yours.
Thanks all for the advice...If I had to send this away, I would need to do it this week in order to have it back by April 1st...Then again, people don't call April 1st...April Fools' Day for nothin.!

[Noah]

Uncas,

It was really easy to replace the fluid. First I smelled it, and it turned out to be lamp oil. I think some compasses use mineral oil as well.

I turned the compass upside down, opened the fill hole and poured in new fluid. It takes a bit to get all the bubbles out, but it really is pretty easy to do.

Noah

[Dan McCosh]

One caveat--most compasses use a light oil, such as mineral oil. A few old ones used alcohol. I've found compass oil in marine supply stores. The problem in using the wrong stuff is that it can sometimes dissolve the lettering paint. Might check around to get the right stuff.

[uncas]

Again thanks....Don't yet know what the medium is...will check...

[Tristan]

Professionals who deal with this sort of thing talk about "compass oil" but keep it damn secret what that compass oil is. I suspect they sniff the fluid and add what seems to smell the same to them. I have a British lifeboat compass that I had shipped over from England about 25 years ago. It developed a bubble ten years ago and I had a chemist friend check the composition with a mass spectrometer. It was 100% ethyl alcohol. I noticed it has, once again developed a bubble. Now where is that bottle of gin my wife has hidden away? Lowell P. Thomas, Naples, FL

[Dan McCosh]

If it's alcohol, use vodka, not gin. Actually, I think mineral oil works, but I feel better using a bottle of stuff labeled compass oil. You use so little, the cost is irrelevant anyway. Another note, however. The bubble usually means at least a small leak somewhere, most likely in the diaphragm or its seal. I've never been able to get it quite tight (on a Danforth-White), but if the air is there, it had to get somewhere.

[uncas]

Dan...there may be a leak...all I can say is that I have had the same size...at least visually...bubble for 5 years. It has not appeared to have changed at all.
With all of the work, I have done on Uncas in the past two years, just thought I should box the compass as a precaution..

[Dan McCosh]

Boxing the compass is probably a good idea. As for the leak--what happens to me is that in cold weather, when the fluid contracts, it sucks in air from somewhere. That's why I end up with this problem every spring. I usually don't even have to add fluid, just unscrew the fill cap, and push it out with the diaphragm.