Fluctuating Altimeter

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tonycondon
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Re: Fluctuating Altimeter

Post by tonycondon »

I called Rudy's and Mid-Continent about a Garwin altimeter overhaul last month. 6 o'clock position.

Both wasted no time telling me it's unrepairable.

New Mid Continent altimeter went in the panel the next week.
Last edited by tonycondon on Sat Mar 19, 2022 9:37 pm, edited 1 time in total.
N2395N
2066
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Re: Fluctuating Altimeter

Post by 2066 »

Of no help, but of interest (at least to me ;) ) -- probably the last shop to repair/recertify these old instruments was operated by Jeanne Bones who flew west in '17. One of the first young ladies to be certified as "Airplane Instrument Inspector", she operated a very small shop and was incredibly responsive to helping some of "us vintage fliers" maintain aging "6 o'clock" altimeters airworthy. In recent years it seems that the only solution is new/rebuilt, 'though it's still possible to find an old one that'll work (may/may not be "certified) in the fly-mart(s). Some early panel covers were not formed to fit the "modern 7 o'clock" knobs -- some were, and some have been/must be modified. Mac
6553
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Re: Fluctuating Altimeter

Post by 6553 »

Thanks for your comments. Will check Rudy’s. Have been looking for new replacement unit but find all have pressure control knob in 7 o’clock position. Do any firms make will manufacture with control in 6 o’clock location? :?:
6277
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Re: Fluctuating Altimeter

Post by 6277 »

I've had luck on ebay.
2066
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Re: Fluctuating Altimeter

Post by 2066 »

"Do any firms make will manufacture with control in 6 o’clock location? :?:"

I haven't seen or heard of any. A few years back there was a "parts vendor" at Sun-N-Fun who had several with "6 0'clock knob" that were tagged as overhauled. When that "news" was shared at the Assoc. type club table there was a quick run to the vendor, and all were quickly purchased by a fortunate few(?) who heard the news. I've suspected since that there may be yet some of them sitting on dusty shelves...somewhere. As already posted, Ebay may be best bet for "finding"...but, if (when) one needs repair the challenge resurfaces. I do know that some (most/all?) shock mount panels actually have the cut-out for the 7 0'clock knob -- there are some panel covers that appear to have a corresponding factory cut-out...and, there are a significant number around that have been skillfully modified for the "modern" altimeters. Mac
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6643
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Re: Fluctuating Altimeter

Post by 6643 »

One of the problems with repairing them is the radium on the dials. I think it has to be removed, but I could be wrong.
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Re: Fluctuating Altimeter

Post by 8224 »

Tony, I have a 6 o’clock Kollsman altimeter with the window at 3 o’clock, stood in front of a mirror and blew gently into the static hole and the big needle jumped 200 feet so I guess it works to some degree. I will sell or trade it but I really have no idea what it is worth. I’m pretty sure it has the radium painted dial and needles. That can be a problem if sent to a repair shop. Ask me how I know! Please e-mail me if interested.
stevehawl@windstream.net
Steve Hawley
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Re: Fluctuating Altimeter

Post by 6277 »

Steve - Next time you fly take it with you and see if it follows your altimeter and Kollsman settings?
6553
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Re: Fluctuating Altimeter

Post by 6553 »

After numerous dead ends, I was able to locate vintage Garwin altimeter at Kelly’s Instruments in Wichita. Nick Ellis did a great job overhauling unit. The new/old altimeter looks brand new and is quite accurate. Highly recommend this shop for instrument repair. :D
2066
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Re: Fluctuating Altimeter

Post by 2066 »

6553 wrote: Wed Apr 06, 2022 11:27 am After numerous dead ends, I was able to locate vintage Garwin altimeter at Kelly’s Instruments in Wichita. Nick Ellis did a great job overhauling unit. The new/old altimeter looks brand new and is quite accurate. Highly recommend this shop for instrument repair. :D
Great news! Thanks for the update!
6553 wrote: Wed Apr 06, 2022 11:27 am After numerous dead ends, I was able to locate vintage Garwin altimeter at Kelly’s Instruments in Wichita. Nick Ellis did a great job overhauling unit. The new/old altimeter looks brand new and is quite accurate. Highly recommend this shop for instrument repair. :D
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