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  #1  
Old 09-26-2018, 04:32 PM
Stockmanreef Stockmanreef is offline
 
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Default Section 40a-08: Axle alignment

So it looks like I have plenty of toe in with the axle alignment. Left side is 2.7 mm (1.5 degrees) and the right is 4.5 mm (2.5 degrees). Assuming I did the measurement correctly. That is $150 to shim the axles, since I will need 5 shims. Another hidden cost. Should Van's be responsible for this cost? Another hidden cost. Plus, after reading another thread about this issue, does the washer need to be shimmed as well. And will the bolt slide through when canted out 2.5 degrees?

what are people typically getting?

I talked to Vans and they said 2.5 degrees is the upper end of the angle.

Thanks
Ken
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  #2  
Old 09-26-2018, 08:18 PM
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RV-14E RV-14E is offline
 
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Quote:
Originally Posted by Stockmanreef View Post
So it looks like I have plenty of toe in with the axle alignment. Left side is 2.7 mm (1.5 degrees) and the right is 4.5 mm (2.5 degrees). Assuming I did the measurement correctly. That is $150 to shim the axles, since I will need 5 shims. Another hidden cost. Should Van's be responsible for this cost? Another hidden cost. Plus, after reading another thread about this issue, does the washer need to be shimmed as well. And will the bolt slide through when canted out 2.5 degrees?

what are people typically getting?

I talked to Vans and they said 2.5 degrees is the upper end of the angle.

Thanks
Ken
Forgive me for suggesting, but it might be worth measuring once more, from the beginning of the process, just to make sure you didn't accidentally overlook something in your initial measurement. Another pair of eyes could help. A feeler gauge can more accurately measure the gap.

I had toe-in on both sides: 0.32° on the right and 0.1° on the left. I shimmed the right side down to toe-in 0.07°. It'd be interesting to see what it is now after accumulating some hours.

The picture below doesn't have the thread taped down as outboard as it can go.


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Last edited by RV-14E : 09-26-2018 at 08:25 PM.
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  #3  
Old 09-26-2018, 10:49 PM
Bavafa Bavafa is offline
 
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I agree with E. Aligning the wood block is a bit tricky and if it is not parallel with the flat part of the axle, it skew the measurement.
Hint, if you donít mind. Create a jig but gluing a piece of wood to the tip of the block in such way that it can sit flat on top of the flat part of the axle. This way you can clamp it in place and know that is parallel and it becomes repeatable.
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  #4  
Old 09-27-2018, 03:34 AM
mturnerb mturnerb is offline
 
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I used the gear legs themselves to check alignment: clamped straightedge to each gear leg, measure distance at the same point on each side (fore/aft). Had to find the math to calculate the angle (sin-1 O/H). In my case, over an 8 inch distance, the difference was less than 1mm: sin-1 of 1mm divided by 25.4mm/inch divided by 8 inches is .28 degrees - this is the total for both wheels (toe-in) or .14 per wheel, which is acceptable to me. (Given how close the total angle is to maximum acceptable, I didn't try to determine individual sides' toe-in)

I don't recommend this as the standard method but could be used to confirm or check your other technique: I'm using Beringer brakes which came already bolted up to the brake/axle assembly - makes it hard to clamp a reasonable size straightedge to the axle - and I didn't want to remove all the already assembled/torqued bolts to check alignment, plus I think it's pretty easy to introduce an error using the clamping technique as noted by Mehrdad.
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Last edited by mturnerb : 09-27-2018 at 03:38 AM.
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  #5  
Old 09-27-2018, 08:45 AM
Stockmanreef Stockmanreef is offline
 
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I will measure again. I am using thicker string than E shows in his picture. The other issue with the measurement is that the axles have an 8.5 degree downward deflection. So when the string is tight it does not run along the entire block of wood I have taped to the axle. So in the picture E attached, the string still is along the back edge of the block. Mine is way off.
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  #6  
Old 09-27-2018, 08:57 AM
Bavafa Bavafa is offline
 
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Hi Turner,
I used your method of long straight edge to confirm my finding and it confirmed the same result. With my jig, since it made it easy to repeat the test to get the errors out, I tested it multiple times including swapping the wood block from L to R and I still came up with the same results.
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  #7  
Old 09-27-2018, 09:17 AM
mturnerb mturnerb is offline
 
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Quote:
Originally Posted by Bavafa View Post
Hi Turner,
I used your method of long straight edge to confirm my finding and it confirmed the same result. With my jig, since it made it easy to repeat the test to get the errors out, I tested it multiple times including swapping the wood block from L to R and I still came up with the same results.
I meant to convey that I was agreeing with you in that the alignment is tricky. Sorry if it sounded critical when I meant to convey the opposite.
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  #8  
Old 09-28-2018, 10:38 PM
Jake14 Jake14 is offline
 
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The simple method I used to check toe-in with the airplane on the ramp (wheel pants off):

1. stretch a length of dental floss tightly between the aft-most point of both main gear tires. The floss should be the same height off the ground at both wheels.

2. Hold a carpenters square horizontally and press one side of the square against the brake disk on one side, with the other arm of the square pointing inwards. Slide the carpenters square backwards until it touches the floss

3. Keeping the carpenters square pressed against the brake disk and touching the floss, measure the gap from the floss at the other end of the carpenters square and compute the angle.

Seemed to work ok, but comments are welcome :-)
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Last edited by Jake14 : 09-28-2018 at 10:42 PM.
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