Whoops lost my rear seat attach bolts... need help

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JSwift
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Joined: Tue Feb 14, 2017 3:01 am

Whoops lost my rear seat attach bolts... need help

Post by JSwift »

Please help if you know the proper size of the bolts that hold the stock rear seat into a ‘52 170B. I have read all the posts about tricks of the trade but I have not seen the sizes. I moved hangars about two months ago with the rear seat out and somewhere my ziplock carefully marked “rear seat install bolts” went missing.

We have Young Eagles flights this Saturday so I need to work this out quickly. Luckily I can get the bolts from a local shop but I would like to start off asking for the proper ones.

Thanks!!!
N2594D, 1952 170B #20746
Near Enfield, CT
Let's go fly!
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Bill_Green
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Re: Whoops lost my rear seat attach bolts... need help

Post by Bill_Green »

A quick look at my old copy of the parts catalog shows these: One each AN3-11A Bolt (Attach rear seat at front), One each AN4-6A Bolt (Attach rear seat at rear), and Two each AN3-10A Bolts (Attach rear seat to brackets)
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GAHorn
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Re: Whoops lost my rear seat attach bolts... need help

Post by GAHorn »

According to the IPC, Pgs 56/57, the bolts are:

Fig 31, Items 1,2,3,4, & 5.

1 AN3-11A (attach seat at front, to floor)
1 AN4-6A (attach seat at rear, to floor)
2 AN3-10A (attach seat to brackets, at side)
2 AN4-11A (attach seat back to seat bottom)
3 AN365-428 (nuts, attach seat back to seat bottom, and at rear floor)

Item 3, AN3-10A bolts are illustrated incorrectly oriented.
Item 4, the bolts/nuts attaching the seat back to the seat bottom are often replaced by owners with ordinary clevis in order to make the seat-back easily removable.

Items 13, 14, 15, and 16 attach the seat belts to the rear seat and consist of one AN4-11A , one AN43-4-47 spacer, and one AN365-428 nut, two AN4-6A bolts two AN365-428 nuts, and two NAS43-4-20 spacers. (The spacers are simply short steel tubes which insert into the seat belt “triangular fittings”. Making your own from steel tubing is a possible solution if you can’t find them.)
Click to ENLARGE
Click to ENLARGE
'53 B-model N146YS SN:25713
50th Anniversary of Flight Model. Winner-Best Original 170B, 100th Anniversary of Flight Convention.
An originality nut (mostly) for the right reasons. ;)
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JSwift
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Re: Whoops lost my rear seat attach bolts... need help

Post by JSwift »

Thanks I appreciate the help immensely!
N2594D, 1952 170B #20746
Near Enfield, CT
Let's go fly!
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ghostflyer
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Re: Whoops lost my rear seat attach bolts... need help

Post by ghostflyer »

I have a golden rule in my hangar. Do not sit on any aircraft seat when not fitted to a aircraft . My back seat was out once and a number of people were using it in the hangar. At that time I didn’t realise the shape of the seat frame changes when people sit on aircraft seats when they are not securely fitted in a aircraft. It took much grunting and words that I can’t use here to finally get it bolted bolted in place. I even cross threaded a floor anchor nut in the process. These days when a seat comes out, it’s wrapped in plastic and stored on the highest rack away from people that have to sit down and talk and waste your time.
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GAHorn
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Re: Whoops lost my rear seat attach bolts... need help

Post by GAHorn »

These rear seats have a personality all their own….. I’ve removed a few of them and virtually none of them fit perfectly back into place without “encouragement”… even if they only sit on a workbench in the interim. :|
It’s very difficult to remove/re-install them without damaging the upholstery/interior unless the seat-back is removed from the seat bottom…and that is especially difficult if the seat back is attached as depicted in the IPC because the AN4 bolts which make up the “hinge” cannot be removed until the seat bottom is released from the side-brackets. This is why some owners have replaced the bolts with clevis’s …or have re-installed the bolts pointing outboard ….and some have used AN4 bolts which allow the use of cotters with washers and avoid the use of AN365 nuts completely.

I chose to use a clevis. (minor alteration)
'53 B-model N146YS SN:25713
50th Anniversary of Flight Model. Winner-Best Original 170B, 100th Anniversary of Flight Convention.
An originality nut (mostly) for the right reasons. ;)
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JSwift
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Re: Whoops lost my rear seat attach bolts... need help

Post by JSwift »

Success,

On Thursday I was able to get most of the correct bolts at the local shop. Most, because as it turns out previous mods to 94D have caused some changes to the nut plates but the key was the two side bolts under the seat. Friday AM I got the rest of the needed hardware and I installed some clevis pins for the seat back attachment that a hangar mate had on hand.

Today, Saturday our chapter flew 48 young eagles. I flew three hops for a total of 8 young ones and one dad.

In general one of my greatest joys in flying is sharing it with others ... photos attached of several happy folks!
First group
First group
Second Group
Second Group
First group
First group
Attachments
Last Group Mom wanted to fly but I only had three open seats.    All great folks.
Last Group Mom wanted to fly but I only had three open seats. All great folks.
N2594D, 1952 170B #20746
Near Enfield, CT
Let's go fly!
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GAHorn
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Re: Whoops lost my rear seat attach bolts... need help

Post by GAHorn »

Great Post! (and pics!)
'53 B-model N146YS SN:25713
50th Anniversary of Flight Model. Winner-Best Original 170B, 100th Anniversary of Flight Convention.
An originality nut (mostly) for the right reasons. ;)
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darhymes
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Re: Whoops lost my rear seat attach bolts... need help

Post by darhymes »

I’m happy to know you were able to reinstall the seat in time for the Young Eagles event. It is such a fun thing to do and a great way to promote aviation.

You’ll probably find the bag of original parts any day now…
Dustin Rhymes
'55 170B N4410B S/N 26754
'06 G550 “The Silver Bullet”
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