1/16" x 5/8" Type 3 groove pin

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Vertical
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1/16" x 5/8" Type 3 groove pin

Post by Vertical »

Need two of these for my trim tab actuator rebuild.

I can't seem to find a source. Anyone have any ideas?

Thanks!
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n2582d
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Re: 1/16" x 5/8" Type 3 groove pin

Post by n2582d »

Preferred Air Parts has some. Search "1/16X5/8". Verify the diameter of the pins you're removing. It looks like there is some discrepancy between Cessna SE73-25 and various C-172 IPC's. The Service Letter calls for 1/16" X 5/8" Type 3 Groov Pins. This is the same as Cessna p/n S2637-4Z10. The C-172 IPC's list 3/32" diameter pins (3/32 X .625 TYPE3) which crosses to Cessna p/n S2637-6Z11. You might be able to get a couple of samples for your project directly from the source -- Groov Pin Corp.

Back in October 2006 Cessna Pilots Association had a well-written article on rebuilding the actuator. PM me if you're interested in getting an emailed copy.
Gary
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Vertical
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Re: 1/16" x 5/8" Type 3 groove pin

Post by Vertical »

Thanks of the reply. I'll ping Preferred Air Parts.

Yep, I'm using SE73-25, and have confirmed that the pins in my outer housing are 1/16". I learned this after I mistakenly ordered the groove pins Mcfarlane sells, which are the 3/32 variety.

My 1955 170b actuator also only has two pins total in the outer housing (one on each end). All other diagrams and references I have seen note four (two per end). -Wondering if that's a known deviation or maybe std on the 170's?

I also considered drilling out the holes to 3/32", but figured it might be better to avoid the risk of a costly mishap, and track down the smaller DIA pins.
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n2582d
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Re: 1/16" x 5/8" Type 3 groove pin

Post by n2582d »

For what it’s worth, the CPA article calls for using a strap wrench to hold the housing to prevent deforming it. Not having a strap wrench, I drilled a 3/4” (?) hole lengthwise through a short 2 X 4. The wood was then cut lengthwise, splitting the hole in half. Like a hotdog in a bun, the housing can now be safely clamped in a vise between the two wood halves.
Gary
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Vertical
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Re: 1/16" x 5/8" Type 3 groove pin

Post by Vertical »

Good call. Thanks.
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