Ramp door flex - hinge line - Page 3

trbomax · 04-12-2016, 07:14 PM

We didnt get the twisting, but our springs wer gone by july last summer,that was only 2 months of use. The springs all rattled when the door was up and went slack when the door was about a foot from being shut.It was all nancy and I could do to lift it off the ground and get it started closeing. FR (supposedly) put new springs on it this winter when they fixed everything else at the factory this winter. We wont be able to go pick it up (they would not transport it either way) untill may 1, then we can start the charade all over.

18CrewDually · 04-12-2016, 10:37 PM

I think I'd rather have the conventional cable roll up overhead spring like my car trailer has. Eliminate all that stress all together.

andy29847 · 04-19-2016, 01:02 PM

Quote:

Originally Posted by andy29847

I think I have figured this out. I took a good look at my new door, including pulling some of the hinge bolts out. The actual door does not extend to the bottom 2 bolts on the hinges. The bolts just pass through the aluminum channel that seals the bottom edge of the door. I am going to make some pieces to try an beef this up.

FWIW, I have a dialogue going with Forest River about ramp door construction and the resultant downtime for my camper over the past 1 1/2 year.

I said: My ramp door failed. The aluminum channel around the outside of the door came loose and water got into the door. Lippert paid for the replacement of the door.

Six months later, the new ramp door was failing. Lippert again stood behind their product and replaced the door. My concern is that the new door is built just like the old one. The engineering for the ramp door is poor. The hinges are short. The hinges do not have a reinforcing plate inside the door (to tie the 3 bolts together). Only one of the 3 bolts in each hinge goes through the actual door. the other 2 go through the aluminum trim piece at the bottom of the door.

Forest River said: I have read your email and I am sorry to hear about the issues you have experienced. It appears that the majority of your problems have been with parts that our suppliers have provided to us. Indiana is the RV capital in the states, the majority of manufactures in the area we all use the same suppliers. Unfortunately, parts will give out which XLR has no control over, so I am really sad that you would not purchase another XLR or recommend to your friends. It sounds like the vendors have stood behind their product and Forest River has taken care of the warranty that was turned into us.
On the ramp door I am waiting for more information from our supplier to find out when your last ramp door was replaced. I’ve been told that they have changed the way they are made and want to make sure that yours is one of the newer. As soon as I find out more information, I will get back with you.

Lippert comments from the engineers:

1. The hinges are very short (compared to the length of the door).
Print 264968 (both current and previous REV H) shows a hinge length of 86.75” with an inside-to-inside extrusion width of 87.75.

2. Only one of the 3 hinge bolts go through the actual door material, the other 2 go through the metal trim. The core extends into the extrusion cavity- the 2 bolts per leaf in question are designed to go through both the core and the extrusion.

3. Also, there appears to be no mechanical bond between the bottom aluminum trim and the side aluminum trim. By design, there is a structural key in each corner that bonds the door together using high strength structural adhesive.

These points all speak to the design of the door. If built to print and used as intended this door should perform as intended.

I replied to Lipperts statement: The number 86.75" that the engineer used must be referring to the width of the full hinge line (7 hinges - matching the width of the door). When I say the hinges are short, I and talking about how far up the door they extend.

I pulled out the 2 lower bolts on my hinges. The cavity between the holes in the aluminum was empty.

About the structural key bonded with high strength adhesive, I can't say yes or no on that. However, given that the doors are failing, and they start to flex as soon as they are used, whatever is in there is not doing the job.

To prove my point on number 2, I removed a bolt and sent pictures showing the bottom of the door is hollow:

Waiting to hear back from Forest River/Lippert now.

WolfWhistle · 04-19-2016, 01:37 PM

So the hinges are bolted to nearly nothing? Certainly nothing structurally sound. Maybe they're putting the hinges on the wrong side! Top instead of bottom. Lippert some day will be a derogatory term.
WW

trbomax · 04-19-2016, 02:16 PM

It already is a derogatory word around here.

18CrewDually · 04-19-2016, 04:48 PM

Quote:

Originally Posted by trbomax

It already is a derogatory word around here.

X2. They have quite the extensive book of excuses. Talk about working harder to get out of work instead of just doing it correctly the first time.

andy29847 · 05-09-2016, 04:04 PM

Lippert sends me this info through Forest River: The two bottom bolts in the door-side hinge leaves do go through hollow section of the extrusion, and the single top bolt goes through the core, so his pictures show the accurate design scenario. Sorry for the confusion.

hahaha - glad I could help them understand their product.

trbomax · 05-09-2016, 05:03 PM

AH---Ha!!! So contrary to what some people have tried to post,there is ,in fact,a CORE!!! I didnt think I had the only one!

andy29847 · 05-09-2016, 06:19 PM

I think the door is a plywood and foam sandwich surrounded by aluminum extrusions. Not sure what you mean by "core".

trbomax · 05-09-2016, 07:30 PM

In a laminated structure such as this,the "core " is the "filler" that is between the outer and inner shell.If it is structural,the core should be bonded to the shell. This is the same principle as a common "I" beam as used in out trailer frames.In an I-beam the part betwewen the top and bottom flanges is called the web. from a structural atandpoint, the web does the same thing as the core.I tdoes not allow the flange or shell to bendin an axis perpendicular to it(flange or shell) because it keeps them from moveingin a plane that is parallel to them.This is called deflection.Most people just call it bending.This is why fiberglass boat hulls have plywood or foam or end grain balsa between the inner and outer bottom.It helps to eliminate flexing,which is what the plywood core does in our ramps.Unfortuneatly,I doubt that the is any bonding in our ramps.If there was,there would be very little flexing.

WolfWhistle · 05-09-2016, 08:04 PM

It is my understanding that the ramp is constructed with 1/16" fiberglass bonded to about 1/4" (7/64"?) Plywood and 1" of Styrofoam. The vinyl anti-skid is glued to the foam. The foam appears to be in two pieces. Besides the aluminum trim you can see there is a hidden extruded aluminum channel around the perimeter only. At least that is my ramp. WW

trbomax · 05-09-2016, 08:46 PM

There has to be something more dense than foam under the non skid. If it were just foam it would have tire tracks from compression in very short order,and the frameing would print thru.Also if it IS foam,why the hell does it wiegh 500#?

andy29847 · 05-10-2016, 05:46 AM

Here is what I believe a cross section of the door would look like:

FWIW, I think the door skin is as Wolf Whistle said, "constructed with 1/16" fiberglass bonded to about 1/4" (7/64"?) Plywood." The skin is glued to the foam to make a sandwich (I like the sandwich analogy better than the I-beam analogy). The door sandwich is lined around the edge with the aluminum extrusion. Per the Lippert Engineer, the aluminum extrusions are joined at the corners with a "glued in key".

I don't have an issue with the door construction. My problems are the way the door is hinged and the springs used at the hinge line to make the door easier to raise and lower.

Using springs at the bottom of the door exerts tremendous pressure on a small section of the door. The pressure is enough to distort the door when it is new. The distortion gets worse with use.

Contributing to the problem is the fact that the hinges are very short.

chpence1 · 05-10-2016, 11:09 AM

I would have thought that spreading the springs force across a broader surface area would have been considered in their design. Or was it just planned failure.

northstar1960 · 05-10-2016, 04:38 PM

Quote:

Originally Posted by chpence1

I would have thought that spreading the springs force across a broader surface area would have been considered in their design. Or was it just planned failure.

After awhile you'll learn the LCI is the same as POS

andy29847 · 05-10-2016, 05:01 PM

I don't think you can blame everything on Lippert. XLR doesn't seem to know or care about the problems customers are having with parts supplied by auxiliary manufacturers. The XLR rep I have been talking to acts like I am the first person ever to have issues with their ramp door. Even worse, they are still using the same door on new trailers. Here is picture of the ramp door for a 2016 toyhauler listed on RVtrader for 106,000.

Tims29hfs · 05-10-2016, 06:22 PM

I only have two springs on my door (2017 29 hfs hyperlite) others have more, either the two springs are real strong or the door is real light. I'll keep an eye on it see what happens. With only two springs it seems to be putting a lot of stress in a smaller area.

andy29847 · 05-10-2016, 06:59 PM

I removed one of 6 springs. My door still goes up and down easily with 5 springs. I'd like to take another one off but it get complicated. The lower half of the hinge is attached with security torx head bolts. That is some interesting decision making to use security torx head bolts on 1/2 of a hinge.

northstar1960 · 05-10-2016, 07:10 PM

Forest river does play a big part in this by the fact they know of issues and do nothing and or keep using the same supplier . LCI is still POS and FR should should look elsewhere and or have them redesign the ramp door . but we both know as long as they get away withh it nothing will change only a few warranty issues will not force them to fix . would need failures on a majority of doors

andy29847 · 05-11-2016, 02:31 PM

I took 2 more springs off this morning. The door come with 6 springs. I am now down to 3. The door still is easy to raise and lower. With 3 springs, the door will go all the way to the ground when opened. Note that the 3 springs are on hinges where I add a piece to spread the load of the spring. I have a lot off confidence that this door will not fail like the others.

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