170B Flap Skin Abrasions

[N2868C]

I have been noticing that I have developed definate linear scratches along the top of the flap skin, where it contacts the top rear wing skin, when the flaps are in the retracted position. Initially, I was planning to put some clear anti-chafe tape along that area, mush the same as many RV builders do. Then, while chatting with my neighbor, who has a Cessna 150 Aerobat, he showed me the fix that Cessna incorporated into his airplane; a nice row of little rubber, or plastic bumpers that prevent the flap from coming in contact with the wing skin. What a great idea.

My flap rollers are in good shape with no wear or slop.

Has anyone noticed this problem on their 170B? And, has anyone incorporated Cessna Fix. My neighbor has extra new bumpers, if I need them!

Tom

[GAHorn]

The Cessna fix is a good one. Their service kit that comes with the buttons has detailed instructions, but it's a simple matter to drill the holes and snap the buttons into place.

[N2868C]

Hey gahorn!

Thanks for the prompt reply. I'm going to do it, but I think that I will search out the Cessna service kit, so that I drill all of the holes in the right spot.

What a great group!

Tom

[n2582d]

Cessna 100 Series Service Manual 1962 & prior

Par. 7-18 INSTALLATION OF NYLON PLUG BUTTONS

a. The Model 150 has 11 plug buttons in each flap. All other models have 12. The plug buttons are installed in the top of the flap (see fig 7-3) 7/8" fwd of the edge of the corrugated skin. All dimensions given are to hole centers.
b. Put flap down . Measure 2-1/2" outbd of the inbd end of the flap and mark a hole center 7/8" fwd of the corrugated skin edge. Proceeding outbd, mark a hole center every 6" until all 12 hole centers (11 on 150) are marked. Last hole center should be aprox 1" (2" on 150) from the outbd end of flap.
c. Using a #17 drill bit (.173) drill a hole @ ea location marked. Deburr all holes and clean shavings from within the flap.
d. Install S-1093-1 nylon plug buttons

[GAHorn]

Thanks, Gary. And for those really picky folks.... use a Q-tip or a fine water-color brush and dab a bit of alodine inside each hole after you de-burr it to retard corrosion at the fresh metal surface. (not too much... you want the alodine to be covered by the button head so it'll be invisible.)

[Robert Eilers]

A little ball of adhesive gasket material in the right place also works.