The left flap on my 170A has a crack, about 2 - 3 inches long that was previously stop-drilled 4 times. It is located on the shear webbing/U-channel right at the inboard hinge. Over the past year, the crack hasn't propagated any further past the last stop-drill. I've been real conservative on flap speeds and limited only to 30 deg. Hopefully this has helped to keep the loads down to a minimum. But now it's time to fix it so I can stop worrying about it.
I've been keeping an eye out for a good used flap, but haven't found any. My IA has suggested having the flap rebuilt, as he thinks putting a doubler on may be more work and more expensive than having it rebuilt/painted. He has suggested Airframe Components by Williams, Inc. in IN. I hope to get an estimate from them tomorrow. Anybody use them, or have a good control surface rebuilder in the Midwest?
I'm also curious if anyone has seen this kind of cracking before? The picture is taken with the flap full down; flap hinge on the right.
Thanks!
Mike
Cracked Flap
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- Mschwarzkopf
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Cracked Flap
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Mike Schwarzkopf
'51 C170A - N1471D
'51 C170A - N1471D
- Mschwarzkopf
- Posts: 44
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Re: Cracked Flap
Quick update...
$1700 estimate from Airframe Components with primer only. Another $750 for paint!
Yeah, we'll be doing this ourselves.
$1700 estimate from Airframe Components with primer only. Another $750 for paint!
Yeah, we'll be doing this ourselves.
Mike Schwarzkopf
'51 C170A - N1471D
'51 C170A - N1471D
- cessna170bdriver
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Re: Cracked Flap
Have you called Del Lehmann at Mountain Airframe for an estimate to repair or rebuild?
Miles
“I envy no man that knows more than myself, but pity them that know less.”
— Thomas Browne
“I envy no man that knows more than myself, but pity them that know less.”
— Thomas Browne
- Mschwarzkopf
- Posts: 44
- Joined: Sat Oct 17, 2015 2:55 am
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Re: Cracked Flap
OMG, are they going to gold plate the flap at that price ? Maybe 250 dollars not painted .
- GAHorn
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Re: Cracked Flap
My wings were rebuilt by Williams in IA and they appear good.
But my flaps were poorly done and corrected by Del, who did a masterful job.
But my flaps were poorly done and corrected by Del, who did a masterful job.
'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.
50th Anniversary of Flight Model. Winner-Best Original 170B, 100th Anniversary of Flight Convention.
An originality nut (mostly) for the right reasons.

- Mschwarzkopf
- Posts: 44
- Joined: Sat Oct 17, 2015 2:55 am
Re: Cracked Flap
Talked to Del today, what a gracious gentleman. $1200 with new skins if needed. If I were going to send it out, I would use him.
I started working on it today. Drilled out about 100+ rivets. Hopefully get the U channel separated this weekend, but with guests in town, not likely
I started working on it today. Drilled out about 100+ rivets. Hopefully get the U channel separated this weekend, but with guests in town, not likely

Mike Schwarzkopf
'51 C170A - N1471D
'51 C170A - N1471D
- DaveF
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Re: Cracked Flap
Guests? I've found 'em useful for bucking rivets.
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