caliper location

How to keep the Cessna 170 flying and airworthy.

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Buckeyejim
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caliper location

Post by Buckeyejim »

My 170A has the brake calipers located to the rear of the gear leg, but I recently
saw a picture of a 170B that has them on the front of the gear leg. Surely that
wasn't changed between models. Which is correct?
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edbooth
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Re: caliper location

Post by edbooth »

Buckeyejim wrote:My 170A has the brake calipers located to the rear of the gear leg, but I recently
saw a picture of a 170B that has them on the front of the gear leg. Surely that
wasn't changed between models. Which is correct?
Rear of the gear leg was the standard location on all 170's. They would work the other way also, but very hard to fit the wheel pant attach bracket if you wanted them. You must realize that there have been so many changes and modifications to these 60+ year old planes, they would fill a large book..... Some of them approved, some of them, who knows..???
Ed Booth, 170-B and RV-7 Driver
Buckeyejim
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Re: caliper location

Post by Buckeyejim »

I wonder why someone would mount the calipers on the front? If these old planes could only talk!
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Bruce Fenstermacher
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Re: caliper location

Post by Bruce Fenstermacher »

Buckeyejim wrote:I wonder why someone would mount the calipers on the front? If these old planes could only talk!
Your brakes and likely all you've seen are modifications from the original Goodyear brakes they came with. So depending on how they were modified, determines front or back. As far as brake operation, there is not difference. Goodyear calipers where behind, and that is where the brake line runs so if you took a poll you probably going to find more aft than forward.
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cessna170bdriver
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Re: caliper location

Post by cessna170bdriver »

Buckeyejim wrote:I wonder why someone would mount the calipers on the front? If these old planes could only talk!
Mine are on the front because I switched from crosswind landing gear and kept the hoses. The routing just worked better with the calipers on the front. Also, they’re in a convenient location to reach down and give them a rattle on preflight.
Miles

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bat443
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Re: caliper location

Post by bat443 »

If you install the dual piston Cleveland wheel cylinders with the FA Dodge STC the kit installation instructions call for installing them forward of the axle.

Tim
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mit
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Re: caliper location

Post by mit »

Golly I wonder why they put them on the front in the later years?
Tim
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GAHorn
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Re: caliper location

Post by GAHorn »

There is a belief by some that by placing the calipers forward they present the back of the caliper to deflect grass and debris instead of allowing those to possibly enter between the brake linings and the disc.
I operate off grass (with aft-mounted calipers) and it appears to me that the gear-leg and axle do similarly. (But, I also operate with original fairings which protect the brakes pretty well.) I doubt it makes any difference from a performance standpoint.
The forward position (in the 3-point stance) provides slightly more ground-clearance and may offer a bit of protection for the linings in the form of "slinging" off of water, etc. from the disc.
'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. ;)
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4583C
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Re: caliper location

Post by 4583C »

gahorn wrote:There is a belief by some that by placing the calipers forward they present the back of the caliper to deflect grass and debris instead of allowing those to possibly enter between the brake linings and the disc.
I operate off grass (with aft-mounted calipers) and it appears to me that the gear-leg and axle do similarly. (But, I also operate with original fairings which protect the brakes pretty well.) I doubt it makes any difference from a performance standpoint.
The forward position (in the 3-point stance) provides slightly more ground-clearance and may offer a bit of protection for the linings in the form of "slinging" off of water, etc. from the disc.
Like this???
C703271A-E9F4-4708-B4E7-5AF9C56365B8.jpeg
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GAHorn
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Re: caliper location

Post by GAHorn »

That's a great illustration, Paul! ... but I believe if you look closely (in person as the pic doesn't allow as much detail) you'll see that the axle mowed the grass and the wheel rotation brought the grass "around" to jam between the brake caliper and the surrounding disc/axle assy. more than actually jam any into the disc-lining area. A C-180 landed out here at my place and I noticed the grass was bunched up on his forward-mounted brake-caliper also, but the owner commented that it usually blows back off in-flight. I don't know how well that might clear-out on the rear mounted calipers as personally I operate with fairings and they keep the calipers clear. You or someone else will have to tell us about that.
'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. ;)
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170C
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Re: caliper location

Post by 170C »

Paul, did Del forget to tell you that 83C isn't to be used to rake hay on the ranch? :mrgreen:
OLE POKEY
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170C
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Re: caliper location

Post by 170C »

No Paul, you can't claim your plane as agricultural equipment for a tax write off. :D
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wabuchanan
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Re: caliper location

Post by wabuchanan »

IMG_0036.jpg
Mine came with pants and front mounted calipers when I acquired it.

Now you tell me I can't write off agricultural use? Shoot........ :?

thumb_IMG_0130_1024.jpg
1950 170A N5776C SN:19730
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c170b53
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Re: caliper location

Post by c170b53 »

I don't know..looks like a very efficient mower to me!
Jim McIntosh..
1953 C170B S/N 25656
02 K1200RS
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GAHorn
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Re: caliper location

Post by GAHorn »

Just a thought while we're on the subject with pics already posted... The brake lines can be subject to damage on unimproved surfaces unless the brake lines are routed behind the landing gear spring/strut for protection. On rear mounted calipers this is easy as long as the hose-lengths are carefully measured when mfr'd. On forward mounted calipers the best way IMO is to route them over the landing gear spring/strut rather than under if at all possible.
Hiding them behind the spring also reduces aerodynamic drag.
'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. ;)
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