Tire wear

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8474
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Re: Tire wear

Post by 8474 »

Thats interesting, my calipers are mounted on the aft side.
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8233
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Re: Tire wear

Post by 8233 »

8474 wrote: Wed Aug 19, 2020 8:30 pm Thats interesting, my calipers are mounted on the aft side.
A lot are on the front side due to wheel extenders. Even if they had been removed, a lot of folks didn't move the calipers. My airplane was like that when I bought it.
David Freeland - CFII
1972 Bellanca Super Viking and 1946 Cessna 120
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Re: Tire wear

Post by 8474 »

Ok, that makes sense.
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Re: Tire wear

Post by cubrath »

8474 wrote: Wed Aug 19, 2020 8:30 pm Thats interesting, my calipers are mounted on the aft side.
Good point. It’s been wrecked more than once, when they put it back together they probably put the axles, along with the shims back on upside down causing the toe out.

Last owner had it for years, can’t imagine how many tires they went through! The new tires I just put on were already showing wear on the inside in the first five hours.

Any disadvantage of having the calipers on the front? Should I swap them to the back??

Thanks for all the input guys!
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Re: Tire wear

Post by 6643 »

I recall the installation instructions for the STC specify mounting them on the front. I also recall that the reason is to keep them out of the weeds. That said, I've seen them both ways; mine have always been on the back. No problems to date.
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Re: Tire wear

Post by 8233 »

6643 wrote: Thu Aug 20, 2020 7:46 am I recall the installation instructions for the STC specify mounting them on the front. I also recall that the reason is to keep them out of the weeds. That said, I've seen them both ways; mine have always been on the back. No problems to date.
When I bought the carbon fiber wheel pants, I had to move my to the aft due to the way they are made.
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1972 Bellanca Super Viking and 1946 Cessna 120
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Re: Tire wear

Post by a64pilot »

I’ve done the Production test flight on many Crop Dusters, and aligned many, many gear.
A tail wheel airplane is slightly more stable with some toe out, the reason is if for example you land in a cross wind with one wheel down, if it’s slightly toed out then that wheel will pull slightly to its side bringing the high wing down.
If it’s toed in, then the tendency will be for the wheel to pull towards the center of the aircraft, and aggravate the wing high condition.
It’s not unsafe, just a little more stable toed out than in. I’ve had them be toed in so bad that on a wheel landing the aircraft would “crow hop” like the brakes were dragging.

You really can tell a lot by pushing the aircraft forward and backwards, if toed out the gear will spread slightly when pushed forward and will tuck in when pushed backwards. The reverse of course toed in.

We would use “grease plates” which was nothing more than two pieces of aluminum plate with grease between them, that way the gear would relax and you could measure the toe in or out by putting a long straight edge against the wheel, a long straight edge makes any toe in or out readily apparent.

We always had an argument that we needed to align them with the tail up in flight attitude, but it didn’t seem to matter.
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