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Old 01-01-2017, 08:07 PM   #1
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A Winter Project - Slide Opening, Frame Repair (Picture heavy)

Hi Fellow Sunliners,

I have a new winter project… This project is not a normal one, but hopefully what has been found and the repairs, can help others. Even if only parts of the repair process is applicable or to become aware of the issue can help others, it’s worth the time to show you this as there a lot of brands of larger campers made this same way. We are going to cover a lot during this project and I will try and keep it to a minimum, but this will be long detailed post. Read as your time allows.

During our last campout this year (late Oct) our slide room tore out the slide seal in one area and scraped the front slide roof when retracting. Infancy signs of this problem have been showing up for the last several years, but never enough to affect the opening and closing of the slide until now. After investigation over the last month, I now understand the problem which was somewhat of a shock to me as I’m in pretty good tune with looking for things like this.

The “symptoms” which started several years back have been, you could see that the slide seal outer flanges are not parallel to the camper seal flanges. Basically the slide is a true 90 degree corner rectangle but the camper no longer has a square cornered opening. By having lots of pictures…, I have concluded the problem started very late 2009 to mid-2010. However in the 2012, the problem progressed enough that I had to adjust the slide out of normal, lift the rear slide arm, to not affect the slide seal from getting yanked out when retracting. This worked for approx. 4 years until mid this year. I have been seeing the issue get much worse over the last year and I was out of slide adjustment to make it work correctly. The camper slide opening is now a parallelogram and leaning to the back to the point where a square slide room will not go through an out of parallel camper slide hole. Ah, not good.

I have had this out of parallel issue with both entry doors as some other forum members have. The door frame gets out of square and the door will not close. I have reset both entry doors over the years and in this case of the slide seals, I “thought” I had to pull the slide out and reset the camper flanges. The only thing at the time that seemed to make sense was the camper was leaning to the back from towing wind pressure over the years. Very slowly leaning ever so slightly and accumulating. It was an educated guess as nothing else seemed to explain the problem. Resetting the rear entry door frame in August of 2010 made the door frame true square again and it is still true square today. Well, at least with the condition of the camper as it is in today. The front door was reset in July 2014, as it too would not close right.

After Thanksgiving (2016), I started to drill down into the problem and was fully prepared to pull the slide out of the camper thinking the slide frame needed to be reset just like the entry doors. I started by documenting the issue and measuring just about all over the slide and the camper opening. From this, the true root cause came to light. The main camper frame rail under the slide is bent down. The frame is bent just behind the rear spring hanger as shown by pulling a string down the frame. The back of the camper is 3” lower than it should be. By jacking up the back of the camper frame 3”, the frame comes back to straight and the slide opening comes back to being square and true with the slide. The good news is, I do not have to pull the slide room out of the camper… I just need to correct the slide damage caused the retracting problem over the years and fix the frame. Both are doable and in process.

Here are some pictures to help show this. This first pictures are “before” the problem. Notice the gap between the slide flange and the camper flange. It is parallel like it should be. These pics are from the year we bought the camper.



This is the lower flange behind the rear left frame hanger. Notice there is no distortion of the lower flange.



Now a few pics of time line leading up to current day. No damage yet in these pics.
2-8-2009 no damage


5-10-2009 correcting lower flange bending. No frame damage




Now the start of damage. Picture taken on 12-11-2010 when adding rear shocks


4-15-2012. Top rear of slide. Gap 3/4"


4-15-2012. Top front of slide. Gap 1 1/8" Must adjust slide arms to shift slide to fit camper hole better. This creates a situation inside were we do not lift off the carpet as much


More on the next reply.
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Old 01-01-2017, 08:13 PM   #2
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Now to current condition, last month 12/2016. These pics shown the lower flange damage (deformation). The rust staining shows this is not new damage. This larger deformation occurred a while ago. To help explain this a little better, when an RV I shape profile frame bends from downward pressure (force), the lower flange distorts (buckles) and the web ( the center part) can also sometimes buckle and the top flange stretches. The heavier the damage like in a wrecked camper, the more the deflection in the web and lower flange. In researching this, I have found pics of wrecked campers online a lot worse. This damage I have is, what I will call, a mild case of deformation. I cannot see any deformation on the top flange or the web, only on the bottom flange.











Here is the slide to the slide opening in the current condition. The rear side. See the camper flange to the slide flange gap.


The bottom rear gap. 1 1/8”


The rear top. 5/8”


The front, the opposite out of parallel direction as the rear, just not as pronounced.


Here you can see the back corner is down compared to the front of the slide. The red line is following a piece of siding from the front of the camper up to the bend area at the front of the slide. From there the siding is tilting downward towards the back of the camper.




Notice the red line above the gutter rail



Here is the frame. It does not look that bent, but the rear overhang is 8 Ĺ feet from the rear hanger, so the bend does not have to be much. There is a string 13 ft 4 in. pulled tight from the before the front axle all the way to the end of the frame. It sags where the frame is bent. Which is only right behind the rear spring hanger.

Starts at front hanger


All the way to the back wall


At the bend area


If I hold the line to the bottom of the frame at the bend point (flat metal plate and C clamp), the frame across the axles is straight and from the bend to the back of the camper, the frame is straight. So I only have one area of damage. That and the fact it was not strong enough the first time.





More in the next reply
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Old 01-01-2017, 08:16 PM   #3
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Now to prove that the frame is the issue, I lifted the back left of the frame rail 3” and the slide opening now comes back to being parallel with the slide.

This square head is adjusted to the current condition. See the gold siding area as a line of reference to the square head (the black thing). This is the current out of parallel condition.


Now raise the frame 3” at the rear




And here is the top of the camper and the slide.
Roof line straight again - front to back


From from the back looking forward




Camper frame now straight across the bend area


The rear bottom slide flange area. Slide wall to camper flange: 2 3/4"


The rear top slide flange area. Slide wall to camper flange: 2 7/8" Only an 1/8” difference now.


So this shows you the problem.

If you are really into this, there are more pics here with word descriptions on many of the pics. Slide Out Of Square Slideshow by JBarca | Photobucket

This problem may be hard to believe, but sometime late 2009 to mid-2010 the main frame had just started to deflect behind the rear spring hanger. That was the beginning. Very subtle, but it started. Then over time, the bend slowly kept increasing. We call this “ratcheting” in the engineering world speak, sort of like bending a paperclip back and forth until it breaks. I know for sure, during mid 2010 we towed out across NYS on I-88 heading west to Cowanesque lake south of Corning NY. This I-88 at the time was brutal with pot holes. There was no escaping it, you were trapped in the right lane with truck traffic whizzing by in the left lane. There was 15 miles of this that even 50 mph I’m sure did not help this situation. I’m not sure if this is what started the problem or took it to the next level.

I have more yet to post, on the problem, the investigation and the fix, but it will come in the next few days.

Thanks

John
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Old 01-02-2017, 07:32 AM   #4
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Wow! Glad you'll be able to fix this! The Tweety frame sagged in the back too, to the point that if the front was level we were sleeping with our heads down enough to be uncomfortable. Not having a slide it didn't matter much, and of course that frame was much smaller. Good thing you have that nice big heated garage!
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Old 01-02-2017, 11:34 AM   #5
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Nice pics JohnB. Checking the pics of your jack stand, behind the rear axle, looks to be close to your bent flange. Since the stand has a "v" shape to it perhaps that started a bend to the flange??? When I have supported my frame I place a flat, straight, piece of metal to take stress from that flange. Even when using my small stands, which I use to take weight from parked position, I place reinforcing at the top of the stand and center the stand on the I-Beam.


At least you have a nice, big, protected area to repair your issues. thanks for the posts.
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Old 01-02-2017, 11:40 AM   #6
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I am using a old netbook with IE Eleven doing my online surfing. When I make a post in here I enter the post and hit submit. The page that reloads should have my post, but it doesn't. I have to hit "refresh", "F5", and that page reload shows my post. This happens on other websites so I know it must be my problem but I just had to tell about it. I know, information overload and out of place. Sorry!


Good luck with those repairs JohnB.
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Old 01-02-2017, 08:03 PM   #7
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Quote:
Originally Posted by Tweety View Post
Wow! Glad you'll be able to fix this! The Tweety frame sagged in the back too, to the point that if the front was level we were sleeping with our heads down enough to be uncomfortable. Not having a slide it didn't matter much, and of course that frame was much smaller. Good thing you have that nice big heated garage!
Hi Pam,

Yes, it is for sure nice to now have a barn big enough to work on the camper. We will have this all fixed up before the early spring camping weather arrives, well at least that is the plan.... well see.

Out of level to make sleeping uncomfortable, ouhhhh. Yes, I am very sensitive to this too. I even have issues walking down an out of level camper. I can tell out of level with the body real easy.

H'mm, your T2753 had the newer style 6" I beam frame. I wonder if the older longer 7,000# class campers had that issue. When we had the 2004 T2499, 26 ft and some inches, we did not have that issues and we where on 5" channel iron. I'll keep track of this thought as I work through this problem we have. Thanks for mentioning it.

Thanks

John
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Old 01-02-2017, 08:48 PM   #8
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Quote:
Originally Posted by Jim-Bev-2363 View Post
Nice pics JohnB. Checking the pics of your jack stand, behind the rear axle, looks to be close to your bent flange. Since the stand has a "v" shape to it perhaps that started a bend to the flange??? When I have supported my frame I place a flat, straight, piece of metal to take stress from that flange. Even when using my small stands, which I use to take weight from parked position, I place reinforcing at the top of the stand and center the stand on the I-Beam.

At least you have a nice, big, protected area to repair your issues. thanks for the posts.
Hi Jim,

Thanks for the good words, and yes the new barn is a camper saver.... Doing this type of work outside is much more complex. I had to do it in the past but as one gets a little more senior, well inside sure helps...

The jack stand V you are mentioning, H'mm, you made me think hard about this one. Thanks for the suggestion. So I did some thinking and looking into this.

A few things, I'm sort of anal about supporting the camper with me under it. I have 2 sets of jack stands (4 each) 6 ton stands and 12 ton stands. In my case not so much for the weight, but for the stability of the stand. If all 4 tires are off the ground, it gets 4 stands. Either 12 tons of stands or 24 tons of stands. But that said, the 12 tons stands are newer, I did not always have them.

Here is the camper off the ground when I had to change the axles years back. 2 sets of 6 ton stands holding up 7,600# of axle area. The tongue jack was still used.




Other than safety, this also reduces the load per jack stand on the frame.

In these kinds of more complex camper problems, I always keep an open mind and listen to all sides of the story. So taking your thoughts I went out to the camper tonight and looked at the stands and the frame to see if the stands could cause the frame bend.

See here, the top arms of each stand. On mine I do not have a V per say, but have a round, does same thing holding a round axle etc, just it is not as deep as some of the V stands like I think you are mentioning.


The larger stands, that curve is so long that I have to use a plate on the stand like you were mentioning. I use a piece a 3 x 3 x 1/4 angle iron on each stand as the curve is almost the whole width of the frame. See here, this would be a problem with no plate:

Now to the 6 ton stands, here the curve is more shallow and on my frame, the lower flange is 2 13/16" wide. Pretty wide. I do not use the plate on these as I get good coverage without the plate.


But, keeping the open mind I looked at all 4 locations tonight on the camper to see if there was any trail of an off center/on an angle jack stand. In the 3 other areas I did not see any signs of bending.

So I put the 6 ton stand arm up in the damaged frame area. This pic does not show the angle well, but for the stand to create this much bend it would have to be a good angle. The base of the stand would have to be at an angle for the top to get this far tipped.


There is also an ear on my stands so in this case, the curved area cannot be over the heavy damaged area. And I have watched specifically all the time to not let the camper down on that ear as that might be an issue. I'm seeing that, in order to bend the flange with the stand, the stand arm needs to the at an angle to the camper flange to be able to push it. At our prior home, I had a concrete pad outside my workshop. The stand was always flat against the concrete. After thinking through this, I'm not seeing the stand can do this amount of damage. I have never had the camper on stands that was not on level concrete.

Now seeing this up close, do you still see that issue? If so, try and explain and I'll check it out.

To see how a really bad I beam RV frame can bend up, see this. I found this trying to see if I could find other failures on line. RV.Net Open Roads Forum: Travel Trailers: Bent Frame and breaks

That post is just the pics. The original poster is up a few replies. In this case the camper left the concrete (air under the wheels) and bounced back down. He never stated exactly what happened to have the camper leave the road, but this was the end result of it hitting the ground and a curb. Odd, he did not know at the time of the accident the frame was bent, that came a year later.... His insurance then totaled the camper. Point in showing this; This was to show how an these RV I shaped frame rails bend under load. Just this was mega times worse than mine.

Thanks for the thoughts, keep them comeing.

John
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Old 01-02-2017, 10:49 PM   #9
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Hi John,

Quite a situation. Do you think some of it could have been prevented if you stored it with the scissor jacks down, and some frame support near the axles? I know the concern with putting the jacks down is if a tire goes flat, it would bend the opposite way, but if an extra set of jacks/stands were put in the middle, would that eliminate that concern?

I'm sure this same thing explains the common cracks above the entry doors.

When I put the new scissor jacks on the '97 this fall, I did note that the C channel frame seemed quite thick. I would say the bottom of the C channel felt more like 3/16", vs. what seems like 1/8" on the 286 and your 310.
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Old 01-03-2017, 09:32 AM   #10
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JohnB, It seems you have researched my idea and it seems to not be related. I guess I am just anal about how my unit is being jacked. when getting bearings greased they use a air operated jack and I now have the service guy trained to put reinforcing on top of that jack. Maybe I'm being unreasonable but I bet I'm not the only customer that is that way, LOLOL!


My reasoning was that the jack used in a weakened point on the frame because of the slide and lesser body support started a weakened point for stress to do further damage. If it happens on other units without slides then I'm seeing ghosts. Now, the real problem is fixing the problem and not so much why. I bet you have it reinforced enuff to not happen again.
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Old 01-03-2017, 10:04 AM   #11
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JohnB, To add to my idea of the weakened I-Beam. The bottom, horizontal, web of the I-Beam is for horizontal stresses, not vertical. The "V" top on the jack puts weight on the outer tips of the horizontal web and that puts the vertical weight at the center of the "V" where the vertical I-Beam web meets the jack has and no support. Why that hasn't made every jack point damaged, I have no idea (maybe the extra weight of the slide), but it does make me think about that one spot. Maybe more stress at that point versus the others.


Also, why did the beam show stresses at that one point, mid-point of the frame, and not closer to the spring mounting point where stresses would be transferred?


Whatever the problem I would reinforce the bottom of the I-Beams for future jacking.


Now I'll stop confusing the problem, LOLOL!
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Old 01-03-2017, 05:18 PM   #12
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A Winter Project - Slide Opening, Frame Repair (Picture heavy)

JohnB, maybe I missed it, but is you're frame a C frame or an I- frame? I think I see a C frame but not certain?

I, like Sunline Fan, recently drilled some holes in my 1996 T-1700 C-frame for jacks and was surprised at the thickness of the metal. Particularly in the corner.

Just curious, good luck.
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Old 01-03-2017, 05:40 PM   #13
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A Winter Project - Slide Opening, Frame Repair (Picture heavy)

Also, that frame in the link you posted looks like junk from the get go to me. Yours isn't destroyed like his, I don't think.
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Old 01-03-2017, 06:00 PM   #14
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JohnB, I finally got the link to the other damaged frame you posted to open (different computer). Notice how that stress is closer to the spring hanger bracket? Also, notice the bottom flange has twisted two ways. One side down and another side up. Your frame seems to be bent up on both sides and further away from the spring hanger bracket. Those pictures do show weight stress on that I-Beam, for sure, since even the main web of the beam is twisted. Your stresses are different, to me, and the reaction of that stress stops closer to where you placed your jack stand instead of at the place that stress should end, at the hanger bracket.


Guess I'm like a dog with a bone now. Sorry
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Old 01-03-2017, 11:16 PM   #15
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Hi Jim,

I picked up your 3 posts. I'm a little short on time tonight but I will leave with these thoughts. I am not seeing the conclusions you came to, "just yet" anyway. You have a few things a little mixed up, but again making me think on this harder, so thank you. Being open minded, in this kind of problem of machine based failure analysis I try and prove myself right or wrong with data.

Tomorrow I will do some calculations on where there jack stand is located which does happen to be right behind the rear axle spring hanger most of the time where the flange deformation is. I know the axle weights and I know the distances from the axle to the stand. I can calculate the downward force of the camper on the stand and try and back into: Can the weight of the camper create enough stress in the lower flange to bend the flange in the curved area of the stand support arm?

There is one thing that you may be missing. I have reinforced the outside area of the lower flange "before" any flange damage started showing up in late 2009/ early 2010. This was done as a preventive measure to stop the frame web cracks that have come with this design of an RV I shape frame rail. Not only Sunlines, but all large heavy campers with this style frame. It is now a known documented problem on the older campers and even some new ones. In 2003 when mine was built, the problem with Lippert frames was not yet understood, now it is. Lippert even sells a fix for this on their web site.... I did the fix a little different. There is a piece of 1/4" flat bar 24 inches long split equally on both sides of the hanger welded on to add support to the lower flange and stop the twisting of the hanger when you turn the camper. Wheels scrub in the turn of a tandem axle setup and stress the flange.

See here. These pics are from 5-10-2009 "before" I started seeing the problem.




This pic was from when I was adding the rear shock absorbers at a later date. The reinforcing plates were already on then. Also look where the jack stand is in this pic, way back. That time I needed more room inside to drill the shock mount holes. There is no frame bend in that area as this pic shows the location of the stand with no added flange support.


The point I'm making about this is, that added support really beefs up the lower flange on the outside. Odds are high it is so strong I could lift the camper at that location off center on the flange and never bend that flange on the outside as the reinforcement is there. This helps the jack stand not flex the lower flange or bend it when it is in the normal location I use.

But again, the inside does not have this reinforcement and that is the area of heavier frame damage. So since your doggie would let go of that bone....LOL, I will do the stress calculation on the inside flange and see if the weight of the camper at that location could bend the inside flange. My gut says no, but the data will prove me right or wrong....

You seemed to be saying the frame damage was not behind the hanger. I'm not understanding what you are saying. The damage "is" right behind the rear axle hanger. There is a small ripple on the outside and a large bugger up on the inside that starts exactly at the end of the rear axle hanger. THe inside deformation is approx 6 to 8" long. See here again

The outside. See the small ripple up of the lower flange. It stops at the added reinforcement. The ripple is maybe 3" long








The inside: Larger frame damage


You can see here, the damage starts right at the rear hanger and bend up.




The RV I shape frame top flange from the end of the rear hanger to the back of the camper is in tension with the camper load on top of it. It is a cantilevered beam in this case. The web, the top part is in tension, the lower part compression. The center is neutral. The lower flange is in compression. On this I shape frame rail of all equal thickness parts, (lower flange, web and top flange, ) the lower flange will buckle in compression when the beam is bending down "far enough". It has to buckle bad enough to start the web section buckling. In my case, the overload was not large enough to cause this. And the added reinforcement on the outside of the flange actually helped that part of the lower flange not deflect as much which is why it is not bent as much.

At the rear hanger of the frame, the frame is very stiff as the spring hanger support is there. The weak point in the frame is just behind the rear axle hanger. The long length of the camper overhanging creates a very long lever prying down and the stress accumulates its maximum moment force just behind the rear hanger. The frame has to be strong enough to take the stress or bend.

My current thoughts are I had a series of mini overloads of force on the slide side from the dynamic loads towing down the highway and hitting a bump, pothole etc. with the weight of the camper. To add to this, that area could of been stressed by all the flexing of the long frame until I added shock absorbers to it. After every bump, I could see the long camper in my rear view mirror, flex up and down 6 cycles until it settled out. Once I added shocks, I only get one cycle. The camper was made in Nov 2003, I added shocks in Dec 2010. For 7 years it ran with no shocks. Think bending the paperclip back and forth, those 6 cycles every bump for 7 years. Granted I did not own the camper until Oct 2007 and I did not think it had a lot of mileage by the prior owner and sat on the dealer lot over a year trying to sell it before I bought it. But we used it a lot between 10/2007 and 12/2010. In hindsight, this long camper should of had shocks from day 1. While it itself did not cause the main problem, it do not help it.

Think on that, I'll be back with more on the jack stand.

Thanks

John
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Old 01-04-2017, 12:04 AM   #16
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Originally Posted by Sunline Fan View Post
Hi John,

Quite a situation. Do you think some of it could have been prevented if you stored it with the scissor jacks down, and some frame support near the axles? I know the concern with putting the jacks down is if a tire goes flat, it would bend the opposite way, but if an extra set of jacks/stands were put in the middle, would that eliminate that concern?

I'm sure this same thing explains the common cracks above the entry doors.

When I put the new scissor jacks on the '97 this fall, I did note that the C channel frame seemed quite thick. I would say the bottom of the C channel felt more like 3/16", vs. what seems like 1/8" on the 286 and your 310.
Hi Jon,

Thanks for the thoughts. I looked at this and no, the jack stands down would not have prevented this. I'm not seeing the problem when the camper is standing still. As fyi I have 3 sets of stands on the camper now. And, on my weight camper, I do not think they will hold the entire weight and not deform them. They could hold some of the weight, but not all. My camper is too heavy.

I am trying to confirm the grade of steel the frame is made out of. Right now the most current thoughts are this is ASTM A36 hot rolled steel. I have done stress calculations using A36 and when the camper is standing still, there is not enough stress in the frame to allow it to permanently bend. Again assuming this is A36 steel. If it is some steel weaker than that, it changes a lot of things.

And yes, the standard weight channel iron frame has a thicker flange on it then these 10" tall I shape frame rails. From what I have found, these I shape frame rails are made for the manufactured housing industry and the RV industry. They are not anything like a real structural I beam or wide flange beam that are used in buildings and other structural areas. The RV industry is trying to create the lightest weight frame rail that can hold just enough load. That's the trick, just enough.

The latest thing now on larger 5th wheels is the new 12" frame. That make this thinner I shape able to carry more weight by the added 2", but they still have to keep it from twisting left to right which is a lot of where the flanges come into play and how many and where the cross supports are on the frame.

Cameo and the older Sunnybrooks use to use (they may still do) stacked tube frames welded together in place of the I shape. That does create a good frame member, however the talk from the I shape crowd says they twist over time and crack the welds holding the 2 tubes together...

Here is a very biased video of a trailer frame builder comparing tube to I shape. But it does show the way the rail distorts. They are in the pro tube crowd. This is a very unfair test as there is no left to right supports on the I shape and they do not talk about thickness and weights of steel. The weak link in this RV I shape can be the left to right support and the very thin upper and lower flange.

https://youtu.be/nIl6RYewN8Y

Thanks

John
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Old 01-04-2017, 12:12 AM   #17
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Originally Posted by johnnybgood View Post
JohnB, maybe I missed it, but is you're frame a C frame or an I- frame? I think I see a C frame but not certain?

I, like Sunline Fan, recently drilled some holes in my 1996 T-1700 C-frame for jacks and was surprised at the thickness of the metal. Particularly in the corner.

Just curious, good luck.
Hi johnnybgood,

The frame is an RV I shape. The top and bottom flanges and the web are all equal thickness and parallel. No tapered flanges like traditional I beams for added strength.

What I have is called a 10 x 9. Meaning 10" tall and 9 lb per foot of running length. The flanges are 2 13/16" wide and 0.168" (3/16" nominal) thick as is the web.

You will not find this thin I shape rail in most any standard industry steel catalog. I finally found one steel mill who makes it. There may be more, just it is hard to search on them as there is not a normal name for these very thin I shapes.

Here is the one steel mill I found. Products - Manufactured Housing Beams - Steel of West Virginia

Thanks

John
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Old 01-04-2017, 05:54 AM   #18
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Lurker jumping in. Looks like you may already know this based on your background, but just wanted to throw this information out in case it does help. On mobile, so apologies for formatting. Throwing in the technical version because it's shorter and sounds like you'd already understand it, but glad to translate for others who'd like if I can get a chance at a keyboard later.

From your photos, that looks like inelastic flange local buckling. That looks almost certain. Your measurements of the flange also show it has a width to thickness ratio of 16.74, which confirms this is possible, the limit on how slender a flange can be to avoid this is a ratio of about 9.2 for this material.

There are some repair methods for this type of failure that have been studied and have predictable results, like this: https://www.omicsgroup.org/journals/the-repair-method-of-damaged-hshaped-steel-members-and-experimental-study-on-recovery-after-repair-2165-784X-S3-008.php?aid=80300

However, that method is for a building, and should be modified for a trailer. If you box to the top flange on your beam, you'll probably get a fatigue failure in your top flange at the end of the weld. Your best bet is a reinforcement that looks just like the one on the outboard flange, as that keeps the welds below the neutral axis and out of the tension zone.

Chuck
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Old 01-04-2017, 06:52 AM   #19
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JohnB, While you aren't doing anything, LOLOL! ....... Looking at the bent, inside flange we can see how the bend is from the spring hanger toward the rear of the TT. It is not so evident from which direction it started. From hanger to the rear? Or from the higher, larger, bend at the rear and then extended towards the front and the hanger. (scratching head) ...... All that math!! Whew!!!!


Good thing Rome wasn't built in a day, huh?


Jim
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Old 01-04-2017, 07:29 AM   #20
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Chuck, That is heavy information. Japan and their quakes have surely bent lots of steel.
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