Thank you, Nic. It took me three tries to get the bubbles out, but it would have been many more tries if I hadn’t seen you tackle it first. You saved me a lot of time and head scratching. Cheers from Boulder, Colorado!
I like the way you got around the problem. The way I did it was to use gaffer tape around the back to make its own bowl and over filled it that way, as I had the same problem, of not having a container the right size to take the compass that did not have such a large volum that it could be filled above the compass rear.
Lamp replacement is super simple. You don't need it apart for that.... just flip up the little cover on the front of the compass above the glass, the globe pops out on a spring, slide new one in....
Well done. Hard to fathom -- a bush mechanic fix that didn't involve Gorilla Tape, GLTs, or WD-40. Surely there was a Leatherman multi-tool involved off camera...?!
Nic First congrats on doing this topic. It is needed and you're the only one showing it. thanks. Question: Which way does the bevel go on the glass? You mention "down" but what exactly does that mean. Is the slanted side facing up or down. In the video it looks like the slanted side is facing up. I noticed the instructions don't tell. They just say, put it back the way it was. Well opps on that. I even have a manual and it doesn't mention it either.
So I remember this little quirk. I figured it out by trial and error... The beveled face goes "down" or facing into the compas body, that's because the cork gasket needs a flat surface to mate against when the front face is screwed down. If you put it on the other way around the glass actually sits proud a bit, and will leak. If you then try tighten the screws up to squash the gasket further the glass will eventually crack
According to Airpath, the beveled edge goes at the bottom and slanted side out. The glass cover is concave, putting pressure on center of the the glass as screws are tightened. Tighten them too much and the glass cracks. Never try to make the cover and the body touch. So, snug them up, then use a straightedge to see how flat the cover has become. Flat is plenty tight enough. If it goes convex you tightened it too much and probably put a stress crack in the glass.
@@dcannon1 Correct, the bezel seal sits between the front fact of the compass housing and the glass.. So which way exactly is "out" in his description? Out as in when you fitting the seal into the housing without the compass body? Or out as in you are fitting the glass into the compass body and then the seal and the front face?
@@NicHolmes Geeze now I'm lost again. I interpreted his description is that the beveled edge faces out of the compass. Your eyeballs are looking to the surface of the glass that has the bevel. Now I also bought a replacement Airpath glass... I've been inspecting this glass for days on end and cannot identify a beveled edge.
Thanks for the video, Nic. How did you remove the rubber gasket debris that must have fallen into the housing? What does the big screw on the top do? Couldn't you fill it through that? I just picked up the same kind of Compass without any fluid in it. So this video will help me. May I kindly suggest for future videos to reduce the volume level for the music.
Amazingly there was no debris inside the housing. The gasket hadn't broken down to that stage yet. I have no idea what that big screw does, however filling it from there will leave you with an air bubble in the compass as the screw is not the highest point in the housing.
Because you end up with an air bubble, the top filler point is not at the highest point in the housing, so to get a complete liquid seal, submersion turned out to be best. or in my case, fill through lens until it overflows.
@@NicHolmes There is an easy way around that. I've been rebuilding aircraft compasses since the 1980s. Close up your empty compass, and remove the filler plug on top with a large proper fitting common screwdriver. fill the compass with an aide like a dropper, pipette, etc. carefully roll the compass around to get most of the bubbles out, and refill it right to the top, and temp install the plug. Now you need a helper. Did you see the air hole on the back of the rear cover? Apply gentle suction to that hole, and remove the plug (can be done with your mouth, but yuk!). Refill the compass and roll it around carefully, but don't break the suction! Get as much air out as possible, and refill right to the top and install he plug temporarily, Now remove the suction, and roll the compass around to get the air to the plug, and loosen the plug. Let all of the excess compass fluid out, and then re-tighten the plug. Be sure that you have no pressure left in the compass, or the diaphragm will rupture within a year.
@@NicHolmes Well, we need to see how to get bubbles out. The instructions mention dunking. I was hoping to see this. But I think you could also get all air out thru the top hole, and maybe you did, but you didn't show moving it around and getting the bubbles out. Loading thru the front doesn't get the bubbles out. You didn't move it around and show the camera. I've don't it several times and it is hard to get them out. This is why I like your topic. I was hoping to see it done completely. Ai bubblesr hides under the compass wheel and it would be nice to see that you got them removed. The hard way I've done it is thru the top opening. You can swirl and move the compass getting all bubbles out from under the wheel and they go to the top. But if the oil is not topped off the bubbles stay near the opening and do not go up. If you keep topping off the filler hole the oil will form a convex swell above the opening and you can get the bubbles to go up into it. So the key on this method is to make a swell of oil on the opening and move the compass until all the bubbles float out and then install the plug.
@@sglynn yeah, you are meant to submerge it. But I found that extremely difficult to get right. The easier approach was over filling it and sliding glass in at an angle to not get a bubble under it. This is method I showed after a few attempts at dunking it. I do not have any air bubbles in mine after that method, even after rotating it around and a few times.
@@NicHolmes Nic thanks for the follow up. Sorry my initial note was too harsh. Thanks for making this video. And thanks for the follow up notes further clarifying you got the bubbles out.
Thank you, Nic. It took me three tries to get the bubbles out, but it would have been many more tries if I hadn’t seen you tackle it first. You saved me a lot of time and head scratching. Cheers from Boulder, Colorado!
That's what I like to hear... That my head scratching has helped someone else save time and effort!
As one of the machinists at Airpath, it’s kinda cool seeing a compass I put together be taken apart by someone online
I couldn't submerge mine either. I ended up filling through the top hole, which took several times, but I was able to get it filled. Great video!
I like the way you got around the problem. The way I did it was to use gaffer tape around the back to make its own bowl and over filled it that way, as I had the same problem, of not having a container the right size to take the compass that did not have such a large volum that it could be filled above the compass rear.
From Gil at Airpath: "The bevel faces “out” - that is, the larger glass surface area faces “down” in contact with bezel seal."
Wish me luck my man - got to do this this week for a failed seal... will be hunting for a container that fits! Also - like the accent... same as mine.
Looks great Nic.
While apart, I would have liked to see how to replace the lamp. A new 99 cent lamp should be added as part of servicing.
Lamp replacement is super simple. You don't need it apart for that.... just flip up the little cover on the front of the compass above the glass, the globe pops out on a spring, slide new one in....
Well done. Hard to fathom -- a bush mechanic fix that didn't involve Gorilla Tape, GLTs, or WD-40. Surely there was a Leatherman multi-tool involved off camera...?!
Amazingly it was lying there but didnt need to get involved
Nic
First congrats on doing this topic. It is needed and you're the only one showing it. thanks.
Question: Which way does the bevel go on the glass? You mention "down" but what exactly does that mean. Is the slanted side facing up or down. In the video it looks like the slanted side is facing up. I noticed the instructions don't tell. They just say, put it back the way it was. Well opps on that. I even have a manual and it doesn't mention it either.
So I remember this little quirk.
I figured it out by trial and error...
The beveled face goes "down" or facing into the compas body, that's because the cork gasket needs a flat surface to mate against when the front face is screwed down. If you put it on the other way around the glass actually sits proud a bit, and will leak. If you then try tighten the screws up to squash the gasket further the glass will eventually crack
According to Airpath, the beveled edge goes at the bottom and slanted side out.
The glass cover is concave, putting pressure on center of the the glass as screws are tightened. Tighten them too much and the glass cracks. Never try to make the cover and the body touch. So, snug them up, then use a straightedge to see how flat the cover has become. Flat is plenty tight enough. If it goes convex you tightened it too much and probably put a stress crack in the glass.
@@NicHolmes From Gil at Airpath: "The bevel faces “out” - that is, the larger glass surface area faces “down” in contact with bezel seal."
@@dcannon1 Correct, the bezel seal sits between the front fact of the compass housing and the glass.. So which way exactly is "out" in his description? Out as in when you fitting the seal into the housing without the compass body? Or out as in you are fitting the glass into the compass body and then the seal and the front face?
@@NicHolmes Geeze now I'm lost again. I interpreted his description is that the beveled edge faces out of the compass. Your eyeballs are looking to the surface of the glass that has the bevel.
Now I also bought a replacement Airpath glass... I've been inspecting this glass for days on end and cannot identify a beveled edge.
Thanks for the video, Nic. How did you remove the rubber gasket debris that must have fallen into the housing? What does the big screw on the top do? Couldn't you fill it through that?
I just picked up the same kind of Compass without any fluid in it. So this video will help me. May I kindly suggest for future videos to reduce the volume level for the music.
Amazingly there was no debris inside the housing. The gasket hadn't broken down to that stage yet. I have no idea what that big screw does, however filling it from there will leave you with an air bubble in the compass as the screw is not the highest point in the housing.
Why didn't you just fill the compass through the filler plug on the top?? ...
Because you end up with an air bubble, the top filler point is not at the highest point in the housing, so to get a complete liquid seal, submersion turned out to be best. or in my case, fill through lens until it overflows.
@@NicHolmes There is an easy way around that. I've been rebuilding aircraft compasses since the 1980s. Close up your empty compass, and remove the filler plug on top with a large proper fitting common screwdriver. fill the compass with an aide like a dropper, pipette, etc. carefully roll the compass around to get most of the bubbles out, and refill it right to the top, and temp install the plug. Now you need a helper. Did you see the air hole on the back of the rear cover? Apply gentle suction to that hole, and remove the plug (can be done with your mouth, but yuk!). Refill the compass and roll it around carefully, but don't break the suction! Get as much air out as possible, and refill right to the top and install he plug temporarily, Now remove the suction, and roll the compass around to get the air to the plug, and loosen the plug. Let all of the excess compass fluid out, and then re-tighten the plug. Be sure that you have no pressure left in the compass, or the diaphragm will rupture within a year.
Sorry, but you did not successfully service the compass. Get more fluid and show the submerge process.
Please explain the successful way then? For the educational purposes of all the viewers...
@@NicHolmes Well, we need to see how to get bubbles out. The instructions mention dunking. I was hoping to see this. But I think you could also get all air out thru the top hole, and maybe you did, but you didn't show moving it around and getting the bubbles out. Loading thru the front doesn't get the bubbles out. You didn't move it around and show the camera. I've don't it several times and it is hard to get them out. This is why I like your topic. I was hoping to see it done completely. Ai bubblesr hides under the compass wheel and it would be nice to see that you got them removed. The hard way I've done it is thru the top opening. You can swirl and move the compass getting all bubbles out from under the wheel and they go to the top. But if the oil is not topped off the bubbles stay near the opening and do not go up. If you keep topping off the filler hole the oil will form a convex swell above the opening and you can get the bubbles to go up into it. So the key on this method is to make a swell of oil on the opening and move the compass until all the bubbles float out and then install the plug.
@@sglynn yeah, you are meant to submerge it. But I found that extremely difficult to get right. The easier approach was over filling it and sliding glass in at an angle to not get a bubble under it. This is method I showed after a few attempts at dunking it. I do not have any air bubbles in mine after that method, even after rotating it around and a few times.
@@NicHolmes Nic thanks for the follow up. Sorry my initial note was too harsh. Thanks for making this video. And thanks for the follow up notes further clarifying you got the bubbles out.
@@sglynn no stress.... its not as simple as the refirb kit instructions make it out to be 😄
If you fly like the same way as you repair that instrument, you will come down short in the future
Thanks for the great negativity,much appreciated