Pietenpol-List: Johnson Airspeed Indicator

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Pietenpol-List: Johnson Airspeed Indicator

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Original Posted By: Galen Hutcheson
BlankI searched the archives and didn't come up with anything, so I thoughtI'd ask. Does anyone have any design tips or even plans for a JohnsonAirspeed Indicator? I would like to build one that is somewhat accurate,but I really don't know what type of spring to use. Any tips?Thanks!Steve RuseDallas, TX---________________________________________________________________________________Date: Wed, 15 Dec 2004 23:36:15 -0800 (PST)
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Re: Pietenpol-List: Johnson Airspeed Indicator

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Original Posted By: Rcaprd(at)aol.com
Subject: Re: Pietenpol-List: Johnson Airspeed IndicatorIn a message dated 12/16/04 12:57:39 AM Central Standard Time, steve(at)wotelectronics.com writes:>Steve,I coppied one from a Johnson Airspeed Indicator that I borrowed from Leon Stefan. After measuring the spring, I wound my own with music wire bought at ahobby store. However, for some reason, I never did try it. It's on my 'List of To Do's.' Chuck G.p.s. Hey Leon, I still have your new Johnson Airspeed Indicator, in the box.________________________________________________________________________________
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Re: Pietenpol-List: Johnson Airspeed Indicator

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Original Posted By: Galen Hutcheson
Subject: Re: Pietenpol-List: Johnson Airspeed IndicatorIn a message dated 12/17/04 10:41:39 AM Central Standard Time, wacopitts(at)yahoo.com writes:>Not to jump in here, but let me try to describe the Johnson ASI. It uses a .047" music wire, with 2 1/2 coils, and has a leg that is bent perpendicular tolock the coil from rotating, and is inserted into the back plate. The coil is 3/4" in diameter, and is spaced off the backing plate with a threaded thru bushing that is 3/8" long. From the center of the coil, to the tip of the pointer, is 7". The bushing that is in the center of the coil is 3/8" diameterand is about 3/32" long. The bolt is about a #6, and on each side of the coilis a plastic washer that is 7/8" O.D. The coil and pivot point is covered witha molded plastic teardrop shape fairing, and has a slot cut for the pointer to travel in. The sweep of the arc is 70. The backing plate with the indicator markings is .040 aluminum, probably 2024. The numbers are 20 thru 90mph. The angle plate that the relative wind pushes against is 1 1/4" X 2 1/8" X .030" thick, with the pointer is on the 3/8" leg of this angle, which is next tothe backing plate. To attach the music wire to the angle plate, it has a small aluminum block that measures 1/4" X 1/4" X 3/4". The .040" wire is drilledthru length wise, and has two #2 (or smaller) set screws to secure the plate, wire, and block.Chuck G.________________________________________________________________________________Date: Fri, 17 Dec 2004 23:02:59 -0800 (PST)
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Re: Pietenpol-List: Johnson Airspeed Indicator

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Original Posted By:
Here's a (small) picture.....----- Original Message -----
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> Re: Pietenpol-List: Johnson Airspeed Indicator

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Original Posted By:>----- Original Message -----
>From: "Jim Markle" >Reply-To: pietenpol-list(at)matronics.com>To: >Subject: Re: Pietenpol-List: Johnson Airspeed Indicator>Date: Sat, 18 Dec 2004 09:05:12 -0600>>Here's a (small) picture.....>
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Re: Pietenpol-List: Johnson Airspeed Indicator

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Original Posted By: Galen Hutcheson
> > > > > >> Contributions> any other> Forums.>> http://www.matronics.com/subscription> http://www.matronics.com/FAQ/Pietenpol-List.htm> http://www.matronics.com/archives> http://www.matronics.com/photoshare> http://www.matronics.com/emaillists>> > > > > __________________________________ http://mobile.yahoo.com/maildemo ________________________________________________________________________________Date: Wed, 15 Dec 2004 23:45:44 -0800 (PST)
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> Re: Pietenpol-List: Johnson Airspeed Indicator

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Original Posted By: >----- Original Message -----
> >Here's a (small) picture..... >
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