axle

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learjetpilot
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axle

Post by learjetpilot »

I recently replaced my wheel and brake assembly with a cleveland conversion kit. The wheel and brake assembly that was on it was a cleveland assembly but the kit was for a 172l. Now the cotter pin holes on the axle and the nut don't line up well enough. The axle is gold colored. Anybody have any thoughts about that. O, I have wheel pants on the wheels.
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Bruce Fenstermacher
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Re: axle

Post by Bruce Fenstermacher »

When you say the cotter pin doesn't line up well I assume you are saying you can't spin the axle nut far enough on to the axle to open the hole in the axle to except the cotter pin. In other words then new wheel seems to be to thick.

If this is the case after assuring there is nothing stopping the bearing from sliding onto the axle and seating properly I would then look at the bearing races in each wheel to see that they are properly seated. If they are not seated all the way in in effect you have made the wheel wider. If you find nothing there the last thing left would be to measure and compare the width of the new wheels at the bearing races with the old and see if in fact the new wheels are wider.

Somewhere along the line you will see why you can't line up the cotter pin hole.

Of course you could have the wrong axles but I'm not sure if Cessna had different length axles. The color gold is probably the cad plating and I don't think tells us much.

I don't see way, after assuring that the wheels are the correct width and and the axles are correct everything is assembled correctly, new cotter pin holes couldn't be drilled. It would be my last resort.
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c170b53
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Re: axle

Post by c170b53 »

Bruce I think you're on the money about the build-up. 49A Can you tell what type of axle you have Solid, hollow, steel? If it has a gold colour then it might be a solid aluminum type with a anodized surface /treatment. If so there will be no room at the axle end centre bottom relief for hole enlargement and as a basic rule, myself, I would avoid adjusting the cotter pin hole. I think I would follow Bruce's suggestion to carefully inspect the assembly.
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Indopilot
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Re: axle

Post by Indopilot »

After all the review and depending on how much adjustment is needed I would dress the nut contact surface before attacking the axle. That is the adjustment recommended in a torque situation involving a castleated nut. Flat even surface with sandpaper and figure 8 movements to evenly dress the contact surface. Shouldn't take more than one or two evenings while watching America's got talent. :lol:
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Bruce Fenstermacher
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Re: axle

Post by Bruce Fenstermacher »

Yes Brad I didn't think about dressing the back or contact surface of the axle nut if it is close but just a bit tight.
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ronjenx
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Re: axle

Post by ronjenx »

I'm always willing to learn, so point me in the right direction.
I've been working on aircraft for 37 years (mostly military, some GA) and have never come across this method, making the nut thinner by any amount, to adjust a nut's cotter pin alignment. Adding or taking away washers, maybe; but not taking material off the nut. It hits me as an unsafe practice.
Can you provide a quote that says this is acceptable?
learjetpilot
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Re: axle

Post by learjetpilot »

I should have been more clear about the holes lining up. The nut that is on the axle is for wheel pants. When I tighten the nut down enought to prevent wheel woble the cotter pin hole on the nut goes a bit past the hole on the axle. This prevents me from getting the cotter pin through both holes. I must back off the nut to insert the cotter pin, but then the wheel wobles. I purchased new axle nuts and will install them today. They are not the kind that will secure wheel pants.
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Bruce Fenstermacher
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Re: axle

Post by Bruce Fenstermacher »

What you need is a washer or thin spacer between the nut and the bearing so the nut is set a bit farther out on the threads and the hole lines up. As big as the axles are these might not be easily found.

Have you tried just swapping the nut from one side to the other? You might find a good compromise for both sides.
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Bruce Fenstermacher
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Re: axle

Post by Bruce Fenstermacher »

ronjenx wrote:I'm always willing to learn, so point me in the right direction.
I've been working on aircraft for 37 years (mostly military, some GA) and have never come across this method, making the nut thinner by any amount, to adjust a nut's cotter pin alignment. Adding or taking away washers, maybe; but not taking material off the nut. It hits me as an unsafe practice.
Can you provide a quote that says this is acceptable?
As for dressing the nut I'm sure Brad and I know I'm not talking about removing any great amount of material. A thousands maybe which depending on the nut design may not even remove any thread material that would have been engaged in the axle thread. This would be a fine adjustment of course and probably rarely do any good and another solution found. So I'm not surprised you haven't seen it. Can I quote a source, no I can't, Maybe Brad could. But I think this like a lot of mechanics techniques comes under common mechanical sense. I'll bet you have learned a lot of mechanics techniques over 37 years that are not documented procedures somewere.
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ronjenx
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Re: axle

Post by ronjenx »

N9149A wrote:
ronjenx wrote:I'm always willing to learn, so point me in the right direction.
I've been working on aircraft for 37 years (mostly military, some GA) and have never come across this method, making the nut thinner by any amount, to adjust a nut's cotter pin alignment. Adding or taking away washers, maybe; but not taking material off the nut. It hits me as an unsafe practice.
Can you provide a quote that says this is acceptable?
As for dressing the nut I'm sure Brad and I know I'm not talking about removing any great amount of material. A thousands maybe which depending on the nut design may not even remove any thread material that would have been engaged in the axle thread. This would be a fine adjustment of course and probably rarely do any good and another solution found. So I'm not surprised you haven't seen it. Can I quote a source, no I can't, Maybe Brad could. But I think this like a lot of mechanics techniques comes under common mechanical sense. I'll bet you have learned a lot of mechanics techniques over 37 years that are not documented procedures somewere.
That's what I was applying when I questioned this technique. There are just too many other ways to adjust for cotter pin alignment. Shaving down (even a little) a castellated nut isn't something I would choose to do.
The axle in question doesn't have two options for cotter pin alignment? The axles on my brother's 170 have two sets of holes, slightly out of phase with the nut's castellations. The nut is never more than 1/2 castellation from a good cotter pin hole.
Last edited by ronjenx on Sat Aug 01, 2009 7:23 pm, edited 1 time in total.
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mit
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Re: axle

Post by mit »

In Alaska we would just throw away the wheel pants! :lol:
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dlinsley
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Re: axle

Post by dlinsley »

Check the dust seal washers, the outside washer has a slightly smaller ID. If it is installed on the inside it will cause the cotter pin holes to not line up.
HA
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Re: axle

Post by HA »

if you're thinking of filing something to fit where before that wasn't needed, something probably isn't assembled correctly. and it will be something simple probably, like the washers in the wrong order or something.

try swapping the axle nuts L to R and see if you gain anything that way, too.

I've seen a spacer on the axle behind the wheel too, look for one of those (std Cleveland part I think) that may need to be thinner/thicker? sometimes they were needed to prevent interference with brakes etc.
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GAHorn
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Re: axle

Post by GAHorn »

The nuts would only have to be tightened an additonal ONE-HALF turn to accomodate the next opportunity to insert a cotter. This should be well within the allowable torque for bearings and wheels. (Answer: Tighten the nut more......aft er you have confirmed you have the correct conversion kit and correct parts for your model aircraft.)
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Joe Moilanen
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Re: axle

Post by Joe Moilanen »

I'm hoping you didn't really mean a HALF turn George.....(:

Joe
gahorn wrote:The nuts would only have to be tightened an additonal ONE-HALF turn to accomodate the next opportunity to insert a cotter. This should be well within the allowable torque for bearings and wheels. (Answer: Tighten the nut more......aft er you have confirmed you have the correct conversion kit and correct parts for your model aircraft.)
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