best replacement fluid for a compass

[kennya]

What is the best replacement fluid for a compass? I have a Richie compass that has a large bubble. I would like to replace all the fluid, but do not have the foggiest as to what to use, oil or alcohol. I sent a quote request to Andrews Compass Service about six weeks ago but no response. Should I not worry with this one and just replace the compass or is repairing this one the better option?

[Zanshin]

They used to be called "whiskey compass" but I don't think the color is right I would recommend using denatured mineral spirits, but that might depend upon your model - what compass do you have (manufacturer/model)?

[kennya]

It’s a Richie pedestal mount from 1980 don’t have the model number on me.

[TrueBlue]

You should only use mineral oil to replace compass fluid.

[sailingwife]

Our boat we just purchased is also missing some fluid. The surveyor said to get it serviced but heck if I can find somewhere and it seems that one could do it themselves. Ours is a pedestal mounted Danforth and on the to do list is to try and remove it to see how it gets filled. I had thought they were filled with glycerin?

[jgeissinger]

Mineral oil is indeed what is in compasses, and a readily available source for same is your local drug store. Baby Oil is pure, clean mineral oil, and it smells good too.

[Zanshin]

Oops, my mistake. The small aircraft compasses need to move around a bit more and thus the mineral spirits; I wasn't paying attention and should have stated "oil".

[hellosailor]

Check with the maker. SOME compasses use alcohol, others use mineral oil, still others use "compass fluid" which is similar to but not the same as mineral oil. Using the wrong fluid can change the damping AND dissolve the printing on the card, or cause the seals to leak again.

I think Ritchie used to have a special exchange program, swapping your compass for a rebuilt one at 1/2 of list price. It's worth asking them.

And if they'll sell you "compass fluid" that's meant for your compass...that's what I'd use, just to be safe.

Baby oil smells good because it has fragrance added to it. If you use mineral oil--use the plain pharmacy grade kind. Fragrance just can't do any good inside the compass.

[camaraderie]

If there is any evidence of leakage around the compass, you may need a diaphragm replacement and not just fluid...in which case that 1/2 price exchange deal might look tempting. I recently had my C.Plath innards replaced and it was about $300 but worth it due to the value of the compass.

[capbillh]

I had been told $150 to rebuild a Gemini 5" compass with new fluid & dome so I bought a new Richie for $115.