Bucking rivets for step

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Jr.CubBuilder
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Joined: Thu Aug 12, 2004 10:33 pm

Bucking rivets for step

Post by Jr.CubBuilder »

Does anyone have suggestions for bucking the outboard rivets during replacement of the boarding steps?

To elaborate, the step runs through the outer skin of the fuselage, and bolts through the edge of the seat rail. Where the step penetrates the fuselage skin, the step itself has a wide flange welded on which fits flush with the fuselage skin. There are rivets going through this flange and the fuselage skin. The inboard set of rivets are fairly easy, they come through the stringer inside the skin, and are angled slightly away from the step. It's the ones on the outboard side that are confounding, they angle in towards the step itself, are hidden on the other side of the step, and it's a hard reach through the inspection hole.

Is there a specific bucking tool that is used for this?
Chris
T. C. Downey
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Re: Bucking rivets for step

Post by T. C. Downey »

It's called a cherry max rivet
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48RagwingPilot
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Re: Bucking rivets for step

Post by 48RagwingPilot »

FWIW, years ago when I converted my C182 to a C180, I dealt with that very issue by using structural bolts and nuts. It worked out very well.
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jlwild
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Re: Bucking rivets for step

Post by jlwild »

I used structural screws with washer and nut inside fuselage on my 170. It took time and patience to start several of the nuts.
Jim Wildharber, Kennesaw, GA
Past President TIC170A (2010-12) and Georgia Area Representative
'55 170B, N3415D, SN:26958, O-300D; People's Choice '06 Kelowna, B.C., Best Modified '07 Galveston, TX, Best Modified '08 Branson, MO.
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n2582d
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Re: Bucking rivets for step

Post by n2582d »

I too think AN525 screws are the easiest way too go. But, if you want to pay for postage both ways you are welcome to borrow this bucking bar.
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Gary
c170b53
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Re: Bucking rivets for step

Post by c170b53 »

As Tom mentioned, I cheated and used Cherry max rivets
Jim McIntosh..
1953 C170B S/N 25656
02 K1200RS
bigrenna
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Post by bigrenna »

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170C
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Re: Bucking rivets for step

Post by 170C »

Two or three years ago I had to remove both of my boardingsteps due to cracks in a previous owner's welding job where the step portion meets the step strut. I went back with cherry max rivets and have had no problems since. My IA said neither of us had the patience or the will to torture our arms to buck the rivets.
OLE POKEY
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Jr.CubBuilder
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Re: Bucking rivets for step

Post by Jr.CubBuilder »

Thanks guys I'm looking at the options and talking to my mechanic as well. I confess I'm a bit stuck on the idea of using solid rivets for the look, but I suppose no one looks down there anyway.

2582D I may take you up on your offer. My mech said to come over and look at this collection of bucking bars, and that AN screws would probably be ok for this application.
Chris
Jr.CubBuilder
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Re: Bucking rivets for step

Post by Jr.CubBuilder »

How difficult are the CherryMax rivets to remove? I have no experience with them at this point. One of my concerns is that I'm a bit chunky and I may need to replace this again before I get a new plane 8O
Chris
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