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  #31  
Old 11-19-2015, 04:33 AM
todehnal todehnal is offline
 
Join Date: Jan 2005
Location: Kentucky Lakes area in KY
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I don't think that the step is being abused when getting in. I think it may be happening when exiting. With the above procedure, you won't see the step, and you will gracefully feel for it, as you gently lower your first exit foot down to it. We use, and like this method.
Tom
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  #32  
Old 11-19-2015, 04:57 AM
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joedallas joedallas is offline
 
Join Date: May 2010
Location: Spring Hill Fl
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Default Vans Review

Ken You are correct
That is why I said (Design the step based on good engineering practice )
And in post #18 - I said (I will not install my steps until van's have finished their review )
I think that the design is on the light side of safety ( the cutout for a flat surface is a question in my view )
I have not seen any photos of the failure or do I have any idea of the number of affected steps.
I think that there are 500 or more sets of steps sold and it would be a expensive to replace them all,
However to keep building all the new steps the same may not be prudent in my view.

And as I stated in post #24 Special instruction for getting in and out of a aircraft is ludicrous.

This is not the way to handle a design deficiency, if there is one
My View

Joe Dallas





Quote:
Originally Posted by rvbuilder2002 View Post
There is a huge difference between a structure being designed to take a specific load, and what can happen as a result of many many load cycles spread out over a period of time.
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Last edited by joedallas : 11-19-2015 at 04:59 AM.
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  #33  
Old 11-19-2015, 06:59 AM
novipilot novipilot is offline
 
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Location: Novi, MI & Venice, FL
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Once again I am reminded of the words a professor used in a Fatigue of Weldments class that I was taking - "Welds are instruments of the devil". Estimating the fatigue life of a welded structure is among the most difficult tasks in engineering.
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  #34  
Old 11-21-2015, 11:42 AM
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gblwy gblwy is offline
 
Join Date: Jun 2007
Location: Perth, Scotland
Posts: 494
Default Another short step!

Thanks for the reminder about exiting backwards. I have exited forwards many times, I thought gently, certainly not jumping on the step.

Recently the step failed when I was climbing in. Not a complete separation but a bend which caught me by surprise. I got the step welded and have purchased a replacement as a spare.

I weigh less than 200 lbs, on a good day ;-)

Cheers...Keith
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  #35  
Old 11-21-2015, 04:57 PM
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joedallas joedallas is offline
 
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Location: Spring Hill Fl
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Do you have a photo of the bad step

I would like a review it



Joe Dallas


Quote:
Originally Posted by gblwy View Post
Thanks for the reminder about exiting backwards. I have exited forwards many times, I thought gently, certainly not jumping on the step.

Recently the step failed when I was climbing in. Not a complete separation but a bend which caught me by surprise. I got the step welded and have purchased a replacement as a spare.

I weigh less than 200 lbs, on a good day ;-)

Cheers...Keith
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  #36  
Old 11-23-2015, 08:16 AM
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gblwy gblwy is offline
 
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Sorry no pic. In fact the step was painted black so would be difficult to see the fracture.

Cheers...Keith
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  #37  
Old 11-23-2015, 04:12 PM
Bob Kibby Bob Kibby is offline
 
Join Date: May 2008
Location: Arlington, Texas
Posts: 127
Default Step Weldament Failure Upate

Van?s replied to my step weldament Failure Feedback Form with an acknowledgement that ?the step has a propensity to crack over time?. Also, that Van?s has an open project looking into the issue but no timeline for the release of a new step. It was Van?s recommendation that I install another step of the current design in the interim.
I received my new replacement step weldament on 11/20/15. The new unpainted step has two small round bumps on the exterior in line with the U-channel on each side of the weldament which extends about 1 ? inches beyond the point where my step failed. These bumps may be evidence of tack welds to hold the components in position for final welding or the bumps may be spot welds to weld the lower part of the step to the channel extension. The consensus of my experts is that these are spot welds intended to weld the lower part of the step to the channel to distribute the loads over the full cross section of the step rather than the partial cross section where the failure occurred. Examining the interior of my failed step below where the step fractured you can see and feel two small bumps of discolored metal protruding from the interior surface. On the exterior of the channel that extends below the fracture (the channel was cracked but stayed with weldament part of the step) you can see a couple of small spots where the metal has been melted but without any significant penetration. These observations suggest that these areas were intended to be spot welds (2) on each side of the channel but did not penetrate the channel enough to fuse the two parts together.
I talked to Van?s Tech Support last week and was told there were no spot welds on the step. On 10/17/15 I sent Van?s 2 photos of my failed step. The exterior spot weld bumps did not show up well since the step was painted. The 2nd photo of the interior of the step clearly showed 2 rough discolored circular areas of heated and melted metal that supported the spot weld explanation. On 11/20/15, I sent Van?s a photo of the unpainted replacement step with the two exterior bumps clearly visible and asked for an explanation.
I received an answer to my 10/20/15 e-mail from Van?s today (11/23/15) confirming that the bumps on the step weldament are spot welds and are intended to penetrate into the channel. The spot welds on my failed step did not penetrate into the channel so that confirms what my experts have been telling me. Since there is no way for me to determine if the spot welds have penetrated the channel (on the new step and old passenger step) we plan to Rosetta Weld each of the 4 areas on each step weldament where the suspect spot welds are evident. This will insure that the parts are welded together and that the loads are distributed to the entire cross section of the step. The Rosetta welds may not be the final answer to the step failures but it goes a long way toward making sure that weld penetrates the channel and loads are distributed as intended.
Bob Kibby ?N712BK?
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  #38  
Old 11-23-2015, 05:41 PM
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joedallas joedallas is offline
 
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Location: Spring Hill Fl
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Default Quality control ?"

Bobbie
I looked at the photos you sent me.
and I think you have a good grip on the problem.
This needs van's attention soon.
I think the welding process needs more checks and testing.
So many things can affect the quality of a weldment.

This may only be a problem on some of the weldments
Quality control ?"

MY View

Joe Dallas
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  #39  
Old 11-27-2015, 10:33 PM
gossend gossend is offline
 
Join Date: Dec 2011
Location: Georgetown, Texas
Posts: 184
Default Pix available?

Bobbie. Any chance you could put those pix up here so we can compare to ours? Thanks!
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  #40  
Old 11-28-2015, 06:28 AM
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joedallas joedallas is offline
 
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Default Photo

Bobbie

If you want I will post it

Joe Dallas
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