Source for gauge lens

[Mike S]

Does anyone have a source for gauge lenses? The lens is cracked on my oil pressure gauge, measures 1.875 diameter, .065 thickness.

[CaptainJon]

Mike,

You might call Keystone instruments in Lockhaven, CT. They do great repair/recertification work and might just sell you just a lens..........

Funny, I just bought a "Taylorcraft Oil Pressure Gauge" with a cracked lens on Ebay last night, which I was going to send to them. Let me know if they will sell you just the lens,

Cheers,
Jon

[Robert Lees]

Try a nearby watch repairer.

[Mike S]

Thanks for the tips. Folks at Keystone were helpful but a bit doubtful they had what I needed. Replacement watch crystals/glass never crossed my mind but that's what I searched for and found on ebay last night.

[CaptainJon]

Mike,
I found a guy with 1.5 mm watch glass, but he was out of the 47.5 mm diameter stuff. You didn't happen to buy all his stock did you? I need one.........

On another note, how does the gauge come apart? I took out the two screws from the back, but that only allowed me to turn the instrument in the case.

Has the watchface glass shown up yet? My gauge showed up with the expected crack........... now to fix it : )

Cheers,

Jon

[Guest]

How come you guys don't send the instrument into a shop and have it repaired?

[Robert Lees]

How come you guys don't send the instrument into a shop and have it repaired?

Because it costs a fortune, and if we can fix things legally under "Owner Produced Parts", it's cheaper & quicker!

[Guest]

Because it costs a fortune, and if we can fix things legally under "Owner Produced Parts", it's cheaper & quicker!

Ah... I see. Thanks Rob.

That would make sense for most of the airplane but owner produced parts is not the only issue with instruments.

Who does or signs off the work is also an issue there. Your friendly A&P can sign off your work on the airplane/engine but not instruments.

In the USA an A&P's privileges do not extend to repairing instruments (part 65.81) and propellers.

So it kinda doesn't make sense here since the A&P is not authorized for that repair and can't legally record it.

I suppose that means that this work does not get recorded.

One year (in the 80's) I had a glass made at a window glass company, he fabricated in from a small piece of rectangular glass.

Lately I just send the instrument into Century instrument or Rudy instrument and have them repair & calibrate.

Pricey, true, but they all work well and easy to read...

Why not cut a "glass" from a piece of acrylic using a hole saw with the drill bit removed?

[Robert Lees]

So I'm learning here, and thanks for the feedback.

If there is no certified overhauler for an instrument on a certified aircraft, how will the aircraft pass its next annual if an un-overhaulable instrument fails? (think: Cessna 152 fuel gauges which are unavailable and unrepairable).

Rob

p.s. Is a US A&P permitted to perform a compass swing? If so, is that not an instrument repair?

[Guest]

So I'm learning here, and thanks for the feedback.

If there is no certified overhauler for an instrument on a certified aircraft, how will the aircraft pass its next annual if an un-overhaulable instrument fails? (think: Cessna 152 fuel gauges which are unavailable and unrepairable).

Rob

p.s. Is a US A&P permitted to perform a compass swing? If so, is that not an instrument repair?

Hi Rob,

Regarding the Cessna 152 I suppose that if there is no over hauler or overhaul process (that might be a big if) then one might replace the entire gauge and sender system (that is a possible fix but perhaps unlikely) although it is done on Aeronca wing tanks.

Usually that stuff works on supply & demand rules so someone will develop an alternative. My friend had a C152 he sold it I will inquire about the fuel guage.

The regulations are defined and there is no implicit guarantee that an aircraft is economically able to continually comply, but usually something works out.



I do not believe that a compass swing is a compass repair I do not recall seeing it listed in that way. I know that you turn some adjusting screws.

See this AC I think it helps => https://www.faa.gov/regulations_poli...mentID/1031648

Or this for direct to .pdf => http://www.faa.gov/documentLibrary/m.../AC-43-215.pdf

It is my untested belief that topping off a compass with compass fluid is preventative maintenance action and not a repair to the compass but since you have to remove the compass an A&P will end up doing it.

Dave

[Hank Jarrett]

Easiest way is to fix an instrument glass is to find an old timer A&P and see what kind of gauges he has in the "junk box" . Pretty easy to remove the glass from a junk one, clean it up and you are on your way.

Hank

Now if any of you come across a bad U.S.Gauge Oil Temp gauge I will even remove the glass, clean it and return the glass just to get the case and instrument face. Looking for a U.S. Gauge Oil temp to experiment with. Also remember only an authorized instrument repair station is supposed to take instruments apart and repair them, so remember not to put your "shelf display" instrument you just fixed into your plane. ;-)

[Guest]

Could you buy one of these or similar and take the glass out?

https://www.ebay.com/itm/2-52MM-12V-60-0-60-AMP-Universal-Ammeter-Gauge-Meter-for-Car-Boat-Truck-ATV/333027531940?_trkparms=aid%3D555018%26algo%3DPL.SIM%26ao%3D1%26asc%3D40719%26meid%3D9f9f087575a3454486d747472fb636f3%26pid%3D100005%26rk%3D3%26rkt%3D12%26mehot%3Dco%26sd%3D163868275432%26itm%3D333027531940%26pmt%3D1%26noa%3D0%26pg%3D2047675&_trksid=p2047675.c100005.m1851

[otrcman]

Hank said, "Easiest way is to fix an instrument glass is to find an old timer A&P and see what kind of gauges he has in the "junk box" . Pretty easy to remove the glass from a junk one, clean it up and you are on your way."

Several years ago I needed to replace the broken glass in a Pioneer altimeter. Nothing else wrong with it. So I called up a well known instrument repair shop in sourthern Calif. When I told the man what I needed, he told me that an A&P was not allowed to do instrument repair. I replied, saying, "That's OK. I'm not an A&P". There was a short silence on the line, then he said, "Give me the diameter and thickness. It'll be five dollars."

Most any glass shop can cut a round shape on a piece of glass. If it's a little too large, you can grind it down with an ordinary bench grinder and a fine wheel. Just be sure to wear gloves and eye protection.

Dick

[Guest]

hank said, "easiest way is to fix an instrument glass is to find an old timer a&p and see what kind of gauges he has in the "junk box" . Pretty easy to remove the glass from a junk one, clean it up and you are on your way."

several years ago i needed to replace the broken glass in a pioneer altimeter. Nothing else wrong with it. So i called up a well known instrument repair shop in sourthern calif. When i told the man what i needed, he told me that an a&p was not allowed to do instrument repair. I replied, saying, "that's ok. I'm not an a&p". There was a short silence on the line, then he said, "give me the diameter and thickness. It'll be five dollars."

most any glass shop can cut a round shape on a piece of glass. If it's a little too large, you can grind it down with an ordinary bench grinder and a fine wheel. Just be sure to wear gloves and eye protection.

Dick

lol!

[Hank Jarrett]

Remember too that the glass is part of the sealing of instruments like altimeters and ROC. Changing theglass and not getting the seal right isn't going to work well. I learned how to rebuild instruments when I was in the Navy and at the rework facility. I am NOT legally qualified to rework instruments, but I have learned how to do it properly. There is a big difference between what is "safe" and what is "legal". All of mine are really nice "displays". That's my story and I am sticking to it.

Hank