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  #11  
Old 09-25-2018, 10:06 AM
iamtheari iamtheari is offline
 
Join Date: Nov 2017
Location: ND
Posts: 196
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Quote:
Originally Posted by rvbuilder2002 View Post
These bearings can tolerate no side load without there being a large increase on friction.
That is the reason for the emphases on using shims and it is likely the cause of your friction as well.
Thanks for your posts above. I'll hope for the best with shims and report back. Shouldn't take more than a month or two of dropping washers and cursing my lot in life.
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  #12  
Old 09-25-2018, 12:09 PM
Tom Martin Tom Martin is offline
 
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It sounds like there should be no issues with this bearing, if, as Scott mentions, it is installed properly. The fact that this tightness has been discussed on this list by folks who are conscientious likely means that there is a good chance that someone might get it wrong.
I have been fixing machinery for over 50 years, building and maintaining RV/Rockets for 25 of those years and I always think of how I am going to fix moving parts when they need to be fixed. I often add extra inspection holes as things that are easy to be inspected will likely be inspected more often.
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Last edited by Tom Martin : 10-03-2018 at 01:05 AM.
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  #13  
Old 09-27-2018, 10:41 PM
iamtheari iamtheari is offline
 
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With one side completely loosened, there is much less friction on the control column. There are visible gaps on both sides so I will have to get some shims in there. I am still working on honing my ability to use The Force to hold the washers and shims in place while inserting the bolt.

However, I wanted to post because there still is some friction with only one side torqued down. If I lift the control column all the way up (full back elevator direction) and let go, it will stay there. If I push down to overcome the stiction, it will drop all the way down easily.

My guess is that I'll need shims on both sides and I'm really going to wish I had magical powers for this process. It was frustrating enough putting those bolts and washers in just once.
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  #14  
Old 09-27-2018, 11:38 PM
n982sx n982sx is offline
 
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Location: Chicago, IL
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Quote:
Originally Posted by iamtheari View Post
... I am still working on honing my ability to use The Force to hold the washers and shims in place while inserting the bolt.
My trick, take a small drill bit thinner or the same thickness as the washer and super glue the last washer to the flat end of the drill bit. You poke it in and the bit will snap right off.

It may still take a try or two but it will be much easier.
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  #15  
Old 09-28-2018, 12:27 AM
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RV-14E RV-14E is offline
 
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Quote:
Originally Posted by n982sx View Post
My trick, take a small drill bit thinner or the same thickness as the washer and super glue the last washer to the flat end of the drill bit. You poke it in and the bit will snap right off.

It may still take a try or two but it will be much easier.
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  #16  
Old 09-28-2018, 08:38 PM
iamtheari iamtheari is offline
 
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Well, I spent an hour on it tonight, mostly dropping washers and cursing. With two thick washers and a shim on the outboard side and a thin and thick washer on the inboard side, the copilot side of the control column is as tightly shimmed as it can get. So I torqued it down and loosened the pilot side to isolate the copilot side bearing. And it is very sticky, just like my original situation.

This is the most frustrating part of the build so far. Mostly because I spent an hour of very tedious work and cannot see any results at all and have no idea why I don't have any results. I hope someone can help me out before I completely lose my mind. Thanks everyone!
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  #17  
Old 09-29-2018, 02:20 AM
mturnerb mturnerb is offline
 
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Quote:
Originally Posted by iamtheari View Post
Well, I spent an hour on it tonight, mostly dropping washers and cursing. With two thick washers and a shim on the outboard side and a thin and thick washer on the inboard side, the copilot side of the control column is as tightly shimmed as it can get. So I torqued it down and loosened the pilot side to isolate the copilot side bearing. And it is very sticky, just like my original situation.

This is the most frustrating part of the build so far. Mostly because I spent an hour of very tedious work and cannot see any results at all and have no idea why I don't have any results. I hope someone can help me out before I completely lose my mind. Thanks everyone!
I had the same situation - spent many hours trying every possible combination of washers/shims I could: finally discussed at length with my tech counselor. He advised me to replace the standard bolt/locknut with a drilled bolt/castle nut/cotter pin: having a bit less torque keeps the bearing from binding. I settled for this compromise since at some point you have to move on....
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  #18  
Old 09-29-2018, 05:56 AM
BillL BillL is offline
 
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Using feeler gauges to determine the last thickness needed is one method of positively determining the shim needed. If an even # of .030 shims don't fit the bill then you can always machine a spacer the exact length needed or Make your own shim the proper thickness.

Be sure to get washer holders or make them. This process is used for other pivot bearings as well. Gluing the majority of the washers/shims together is a major positive step in the final assembly, so only one is left to be inserted with the holder. Leaving the .063 one separate is most easy. Proper technique and this whole process is easy and straight forward.
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  #19  
Old 09-29-2018, 06:46 AM
mturnerb mturnerb is offline
 
Join Date: Apr 2015
Location: Ponte Vedra, FL
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Quote:
Originally Posted by BillL View Post
Using feeler gauges to determine the last thickness needed is one method of positively determining the shim needed. If an even # of .030 shims don't fit the bill then you can always machine a spacer the exact length needed or Make your own shim the proper thickness.

Be sure to get washer holders or make them. This process is used for other pivot bearings as well. Gluing the majority of the washers/shims together is a major positive step in the final assembly, so only one is left to be inserted with the holder. Leaving the .063 one separate is most easy. Proper technique and this whole process is easy and straight forward.
The challenge isn't just the overall shim thickness. I don't know how the -14 compares to other models, but I found that some of the issue is how one side moves when the other is tightened. I can't tell you how many times I tightened one side, all was good, carefully followed the shim process on the other side and found stiffness. I tried carefully alternating sides as I tightened them etc. Just never found the exact perfect combination. (And I did try making custom shims, using feeler gauges etc.)
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Last edited by mturnerb : 09-29-2018 at 06:49 AM.
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  #20  
Old 09-29-2018, 09:23 AM
smash smash is offline
 
Join Date: Apr 2013
Location: Fair Oaks,CA
Posts: 52
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I had a problem getting the control column to move freely. When built correctly, there is almost no friction and mine was sticky no matter how I adjusted the shims.

I discovered that while back riveting the bearing bracket assembly, I had accidentally positioned the backing plate under the bearing and slightly marred the bearing surface. I didn't realize this until I tried shimming and could not get the assembly to move freely.

The solution was painful- I had to remove the cover rib to gain access to the bearing bracket assembly and then disassemble it. When I removed the bearing, it was stiff when I tried to move it with my fingers and on closer examination I found some scoring on the bearing surface.

Remove the control column and try moving the empty bearing with your fingers- it should move absolutely freely with no catching.

Here's my build log writeup: http://www.smashsrv-14build.com/2016...ishing-up.html
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