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Safety Wiring my prop

Doubtful

I used 65-foot lbs. and easily removed the nuts several times. My guess is 100's have also used the same torque specs. Most OEMs allow for plenty of safety margins to their specs. You need to have a properly calibrated torque wrench and allow for the added length of the shorter prop wrench used. It's good you got your prop back on. Where did 47 come from?
 
I used 65-foot lbs. and easily removed the nuts several times. My guess is 100's have also used the same torque specs. Most OEMs allow for plenty of safety margins to their specs. You need to have a properly calibrated torque wrench and allow for the added length of the shorter prop wrench used. It's good you got your prop back on. Where did 47 come from?

It depends on the bolt size, 1/2" is 65 ft-lbs, 7/16" is 47. I've got the smaller bolt. Numbers are from the prop manual. 65 was shown on the single page insert for my prop. Here is the excerpt.

Torque and safety wire the propeller hub bolts. Refer to data
sheet for torque (dry, non-lubricated) values (65 ft-lbs for ½”
hardware or 47 ft-lbs for 7/16” hardware). Safety wire the prop bolts
in pairs with 0.32” stainless safety wire after installation

For what it's worth, 47 certainly seems like plenty of torque and I'm not using the same torque wrench as I did for the initial installation. I believed a used the less accurate needle style wrench initially, I'm now using a click type wrench and am using it properly. I just looked at the notes I made for the initial install, although it didn't state what I used for a number, I did have problems getting a wrench on 4/6 bolts and only torqued 2, I used a wrench to roughly match the torque on the others. I'm sure that wasn't what I was supposed to do, but it's what I did and it would have been because of the size of that needle style wrench. Looking at the data sheet that came with the prop and the poorly written manual, I have little doubt that I would have used the 65 from the data sheet. The torque instructions and values are only shown under the single piece bulkhead instructions and I have the 2 piece.
 
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I would recommend you keep an eye on the torque by rechecking occasionally (25hrs), you also overstressed the threads in the crank lugs by over torquing by approx 40% :eek:
IMO you should have replaced the crank lugs. Pretty hard to throw rocks at WW for your troubles.
 
I would recommend you keep an eye on the torque by rechecking occasionally (25hrs), you also overstressed the threads in the crank lugs by over torquing by approx 40% :eek:
IMO you should have replaced the crank lugs. Pretty hard to throw rocks at WW for your troubles.

I have no problem throwing rocks at WW, the only reason I would have used the incorrect torque is because that's what they told me to do on the data sheet that came with the prop. The prop manual doesn't even mention tightening the bolts, let alone torque and wire, for the two piece rear bulkhead installation (it does for the one piece, the only place you'll find 47 in the manual). The manual also shows only 65 ft-lbs for the 50 hour inspection. Then when they had the prop for teardown they didn't even look at the roll pins, despite replacing them being listed on their website as part of the teardown, along with complete disassembly of the prop. There is no way they should have missed a sheared roll pin. Then it took them more than 2 months to get me the right parts to fix the issue. While I'm quite happy with the prop itself and WW did eventually get it right, don't list me as remotely satisfied with their service or feeling like I hold the primary responsibility for my troubles.

As far as the suggestion to replace the crank lugs, that may well be the correct thing to do. It was my engine builder/AME who did the reinstall yesterday with my assistance. He was aware of the likely over-torque. He did have a good look at the lugs but didn't say anything about them. I'm not sure how I would check the torque without removing the safety wire, but I will at the very least check that the safety wire is still taut and in place properly.
 
I have no problem throwing rocks at WW, the only reason I would have used the incorrect torque is because that's what they told me to do on the data sheet that came with the prop. The prop manual doesn't even mention tightening the bolts, let alone torque and wire, for the two piece rear bulkhead installation (it does for the one piece, the only place you'll find 47 in the manual). The manual also shows only 65 ft-lbs for the 50 hour inspection. Then when they had the prop for teardown they didn't even look at the roll pins, despite replacing them being listed on their website as part of the teardown, along with complete disassembly of the prop. There is no way they should have missed a sheared roll pin. Then it took them more than 2 months to get me the right parts to fix the issue. While I'm quite happy with the prop itself and WW did eventually get it right, don't list me as remotely satisfied with their service or feeling like I hold the primary responsibility for my troubles.

As far as the suggestion to replace the crank lugs, that may well be the correct thing to do. It was my engine builder/AME who did the reinstall yesterday with my assistance. He was aware of the likely over-torque. He did have a good look at the lugs but didn't say anything about them. I'm not sure how I would check the torque without removing the safety wire, but I will at the very least check that the safety wire is still taut and in place properly.

I you are concerned about the lugs, run a a good quality tap trough them. If no shavings come out, the threads have not been deformed and not likely to be compromised. If you get a bunch of metal chips, the threads have deformed and should be considered compromised. Threads are not usually the weak link and the bolt shank is what becomes compromised from a moderate over torque (too much stretch weakens the material, the amount is based upon the alloy used). Severe over torques can and will deform threads before the bolt shears, again depending upon the alloy.

Larry
 
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I you are concerned about the lugs, run a a good quality tap trough them. If no shavings come out, the threads have not been deformed and not likely to be compromised. If you get a bunch of metal chips, the threads have deformed and should be considered compromised. Threads are not usually the weak link and the bolt shank is what becomes compromised from a moderate over torque (too much stretch weakens the material, the amount is based upon the alloy used). Severe over torques can and will deform threads before the bolt shears, again depending upon the alloy.

Larry

I’m pretty sure I know what the answer would be if you ask Lycoming or Hartzell about overstressed lugs.
Anyone that has stripped a bolt/nut assy understands that both items get replaced due to deformed threads.
And as far as verification of torque by checking safety wire, we’ll let’s just say that’s not a good indicator of torque.
Not knowing the size fastener and the appropriate torque value is on you/installer, a good case of “you don’t know what you don’t know”.
You even posted the quote above from the manual stating size hardware/torque requirement.
 
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I’m pretty sure I know what the answer would be if you ask Lycoming or Hartzell about overstressed lugs.
Anyone that has stripped a bolt/nut assy understands that both items get replaced due to deformed threads.
And as far as verification of torque by checking safety wire, we’ll let’s just say that’s not a good indicator of torque.
Not knowing the size fastener and the appropriate torque value is on you/installer, a good case of “you don’t know what you don’t know”.
You even posted the quote above from the manual stating size hardware/torque requirement.

Well I'm going eat some crow here. I just came back from putting the spinner back together and I checked the data sheet. It lists both bolt sizes and the appropriate torque. The manual still doesn't show it properly, the part I quoted that showed the 47 number was for the one piece bulkhead which I don't have. I'll never really know if I over-torqued the bolts, but if I did, I'll have to own most of the blame. Doesn't absolve WW for the poor service though.

I did apply some torque seal before putting the spinner back on. As for the suggestion of running a tap in, I did that, although I didn't run it deep. It didn't produce any metal and wasn't particularly easy or hard to do.

In any case, my plane is fully assembled and ready to fly now. I ran out of daylight today, I've been grounded for 5-1/2 months, my first flight back is going to be in very good VFR daytime conditions. That may be tomorrow afternoon.
 
WW Overhaul

After reviewing what WW performs in their overhaul, I can understand why the OP is a little disappointed. They do "say" the perform a lot of replacements in their normal tear-down. If they performed everything, they documented my guess is would be pretty expensive: (Walt welcome to chime in what you think the charge would be since you know the time and material charges better than most)

Whirl Wind Standard Tear-Down Inspection Service
Our standard, base rate tear down inspection service includes the following parts and labor:

The propeller is completely disassembled. All components are thoroughly cleaned and inspected for wear and / or fatigue
All o-rings are replaced (blade, hub, oil tube and piston)
Cylinder gasket is replaced
Ball bearings and separators (where applicable) are replaced
Roll pins are replaced
Pitch link bushings are replaced
Blade snap rings are replaced (when required)
Pin bases are inspected for fatigue (Magnaflux)
Pin base bolts are replaced (where applicable)
Counter weight hardware is replaced (where applicable)
All necessary hardware is replaced
Blades are shimmed as required (new shims may be necessary)
Propeller is statically balanced

I had mine "rebuilt" because the airframe was in Ohio and spitting grease at 250 hours. I think letting it sit in paint exaggerated the separation of the grease and after 5 months there must have been pockets of light weight grease that came out. This issue is a well-documented problem in many prop manufactures and I think WW now is using a grease that will not separate as easily. Bottom line is they charged me a fraction of the costs of a normal overhaul even though it was clearly out of warranty. I did not expect them to perform a major teardown and did not pay them for this, so no roll pins where exchanged.

It would be interesting to hear what others are paying for their teardowns (and if all the documented replacements are performed) I accepted there would be some additional costs along the way for this prop. I wanted an all-composite prop, and the alternative was going to Hartzell with the costs almost double a WW and at that time could not have it painted. I have been extremely pleased with my WW. Everyone comments how smooth it is and I like that the smoothness very much. It also looks great.
 

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