Seat Rail Replacement

How to keep the Cessna 170 flying and airworthy.

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Kyle Wolfe
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Joined: Mon Mar 17, 2003 12:30 am

Re: Seat Rail Replacement

Post by Kyle Wolfe »

Where’s the current ‘go to’ place for seat rails? Still McFarlane? Annual planning underway and that may be on the list this year.

(Or maybe someone has a couple sets they need to get rid of?)
Kyle
54 B N1932C
57 BMW Isetta
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jcsand
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Re: Seat Rail Replacement

Post by jcsand »

Has anyone used the approved screws to attach the seat rails rather than rivets as advertised at McFarlane Aviation when replacing seat rails?
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GAHorn
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Re: Seat Rail Replacement

Post by GAHorn »

The McFarlane seat rails are slightly “beefier” than OEM. https://www.mcfarlaneaviation.com/produ ... ails/faqs/

The website has some illustrations as well as a link to the Special Airworthiness Information Bulletin CE-90-03R2 https://www.mcfarlaneaviation.com/media ... 0-03r2.pdf permitting screws instead of rivets.
'53 B-model N146YS SN:25713
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DaveF
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Re: Seat Rail Replacement

Post by DaveF »

jcsand wrote:Has anyone used the approved screws to attach the seat rails rather than rivets as advertised at McFarlane Aviation when replacing seat rails?
I have used screws for the larger diameter fasteners at the ends of the rails. You just have to spot-face the locations on the rail to make sure the screw heads have a square seat. This picture shows the old rail I used for practice and the new rail freshly spot-faced.
9D379BF0-7689-43E3-8C42-891E713F9702.jpeg
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cessnut
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Re: Seat Rail Replacement

Post by cessnut »

The only place I have ever installed screws is at the ends where they tie into the bulkheads, when the rivet holes were questionable. I have seen them installed with screws and thought it looked cheap. If you can reach in and install a nut and washer, why not just buck a rivet? Since it requires a structural screw, it seems you would have to upsize all your holes to accommodate a #8 screw.
McFarlane rails may be beefier, but they don't seem to have the strength of the originals. I once demonstrated this by taking a misdrilled one and bending it around my knee.
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jcsand
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Re: Seat Rail Replacement

Post by jcsand »

Thanks for your time/thoughts regarding screws vs. rivets in the seat rails. I think that I'll go with rivets.
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cfzxo
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Joined: Sat Oct 19, 2002 3:29 pm

Re: Seat Rail Replacement

Post by cfzxo »

cessnut wrote:The only place I have ever installed screws is at the ends where they tie into the bulkheads, when the rivet holes were questionable. I have seen them installed with screws and thought it looked cheap. If you can reach in and install a nut and washer, why not just buck a rivet? Since it requires a structural screw, it seems you would have to upsize all your holes to accommodate a #8 screw.
McFarlane rails may be beefier, but they don't seem to have the strength of the originals. I once demonstrated this by taking a misdrilled one and bending it around my knee.
I wonder if the older seat rails have work hardened over time?
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