Lippert frames
Been towing for 30 years, but never heard of a Lippert frame. Seems like most of the comments are negative.
So, what is a Lippert frame?
So, what is a Lippert frame?
Forum Discussion
JBarca wrote:
I cannot find these thin H shapes "yet" in any hand book, but they do make them for the Manufactured Housing market. They call them MH beams or thin I beam. Here is one mill that makes them. So far that is the only mill I can find them on the web that does. I'm sure there are more, just I have not found them.
http://www.swvainc.com/housing.html
You will notice they offer a 10 x 8#/ft and a 10 x 9#/ft which I have and it has an area moment of inertia of 35.5 in.^4th.
Thanks for posting that link. Interestingly I think we have done some business with those guys in the past on something. I don't remember all of that stuff but my estimator will. I doubt you'll find any info on those MH beams in any bible, either printed or the net version. To me those are custom pieces. Maybe not so if you're a manufactured housing builder, but the website also seems to indicate they'll run those to order. I've got a fab guy I use for small stuff who used to be one of "the guys" at American Bridge. If it was made in the last 100 years and has published info he'll have it, or know where to get it lol. That's if he has not keeled over lately as he's about 85 but still going at it...I think.
On a side note reading through the company history, those WV guys may have been the inventors of the micro mini mill. Back in the day there were many here around Pittsburgh, not so much now days.
In the last few years I can not bring myself to believe Lippert would still be using those. I can see 03 or even 2010, but with what they have acquired and have become in the in the last 10 years since they bought up everyone and everybody, who was into frames....almost,...I'm skeptical. I know they did a major outlay a few years ago for continuous welding equipment, read that in a trade pub.
It's neither here nor there, but I once had a long conversation with a broker over drinks about what Lipperts buyers look for when they go out shopping materials.....I won't go deeply into it, but will just say they apparently go looking for what others are not looking for, if you get my drift.- John, I noticed something made out of wood attached to your frame. It appears to be able to swing down. What is that?
- Also, Arctic Fox uses the rolled MH beam too. Or they use too.
Ralph Cramden wrote:
Here is why I think you're mistaken and the 10" high frame rail in your picture is a machine welded piece, and not a conventional hot rolled member. They make hot rolled H shapes (we call them a wide flange or W) or I shapes (A Jr / I, or S), only in specific readily availible sizes and weights. Going by your picture the flange width is roughly 2-1/2" wide. I determined that by comparison to the two fittings installed on the black tank. One is 1-1/2", the other 3".
There is no H or I which is hot rolled that a company like Lippert could buy from a hot mill, that would be those dimensions in a 10" height. It simply does not exist unless its a custom hot rolled shape and cost would not typically allow that.
In your picture you have a 10" height, a 2-1/2" flange width, and a 1/4" thickness both at flange and web based on the measurements you took.
Here is what you can get from a hot mill.
There are a couple dozen made with a 10" size in a wide flange, but none including the lightest which is a W10X12(lbs per ft), has a flange width smaller than 3.960 inches. Then they go up from there. The only size in a wide flange that has anywhere close to 1/4" average thickness at both flange and web is a W10X15, with a 4.00 flange width. The web is .230 and the flange is .269
There are only two readily available sizes in a Jr/I/S with a 10" height.
S10X25.4 or 10.000X4.661, The flange is 4.661 wide, and the thicknesses are flange .491 / web .311
S10X35 or 10.000X4.944, The flange is 4.944 wide, and the thicknesses are flange .491 / web .594
That's why I think your main rail is an engineered / fabricated / machine welded shape. That is unless Lippert is having hot rolled shapes custom made at great expense, or own a hot mill and making their own. Not sure why they would want to. The size is not available unless its fabricated. Maybe I'm wrong.
Hi Ralph,
There was a period of time when Lippert was able to get hot rolled MH beams. They might still be able to, I don't know. I have one made in Nov. 2003 and Hunting Dog's has one too although his is a little heavier than mine.
I cannot find these thin H shapes "yet" in any hand book, but they do make them for the Manufactured Housing market. They call them MH beams or thin I beam. Here is one mill that makes them. So far that is the only mill I can find them on the web that does. I'm sure there are more, just I have not found them.
http://www.swvainc.com/housing.html
You will notice they offer a 10 x 8#/ft and a 10 x 9#/ft which I have and it has an area moment of inertia of 35.5 in.^4th.
Huntingdog's frame is closer to a 10" x 13.2#/foot with an area moment of inertia of 50.6 in.^4th. His vintage is stronger and the one he ended up with was a good one. I wish mine was that heavy, close to 42% stronger given the same steel. He has a higher GVWR on his camper then mine too. Mine is only 10,000#. Dog's is 11,500#
Here are some rusted pics of mine. I have since cleaned that rust off and painted it after my repair and these are all I had on my web server that sort of showed the radius. They are rolled.
Here is a closer one of the radius
These beams are for sure thin. They do make them from HSLC steel in the 50ksi yield range. In order to help them not deflect, they are welding beads on the top flange to heat/shrink in some positive camber at the rear hanger area to help the overhung loads keep the beam straighter. This have been ongoing in the industry for a long time.
If you ever find a handbook of these, please let me know.
To the topic of Lippert frames, in my case Sunline used them as a subcontractor. They had an east coast plant near their factory and they use to make products for Skyline too I think back in the day. And as far as subcontractors go, if the firm hiring them accepts poor quality that is problem 1. In my case my frame was not made that bad although I had issues they could not weld hangers on in the correct location. They just plain screwed up. If all the big RV manufacturers are accepting poor quality they are paying for, in my book they are as bad as the ones who made it.
Hope this helps
JohnHuntindog wrote:
As for your other pic showing a person welding and stating he is not a robot... That is true. But it is also true that he is NOT welding a 3 piece I beam together.
If you're so quick to criticize at least direct that criticism at the right person - me. I posted that pic, not RC, but nowhere did I say that person was welding a frame, it was merely in response to JCR-1 who said he thought all welding was now done by robots, which is clearly not the case.Ralph Cramden wrote:
A couple of seemingly small observations.Huntindog wrote:
I do not know what "rolled" means. I DO know what welded looks like. I have seen that on many TTs.
I DO NOT have a welded frame rail frame.
It is what I consider to be a "normal" I beam.
Simply put there are two methods used to make a structural shape. Hot rolled or cold rolled. Specifically in relation to an H or I which are a complex shape, there are two ways to make them. Hot rolled is steel goes in one end of a plant, and an I or H comes out the other. Its then shipped to a fabricator who cuts it, drills it, fabricates it.
The other way to make an H or I, is you take 3 pieces of plate or sheet, and weld them together. That's it, two options. You can cold roll a C, or an angle, or a Z or a bar, and a lot of other shapes, but you can not cold roll an H or I. Those are the simple versions. This Article explains it better than I can.
All of that said I am not saying an engineered/machine welded member is a bad thing, as I have built a couple million square feet of pre-engineered industrial facilities. Almost every beam, frame or column, and almost every structural element in one, is engineered and made from machine welded shapes. We have hung some overhead cranes from them at times. Its all about it being engineered correctly.
I don't know how one can say "I DO know what welded looks like. I have seen that on many TTs. I DO NOT have a welded frame rail frame."
Frankly if the equipment used to weld those 3 pieces together is maintained and set up correctly, you're not going to be able to tell visually as that weld will be smooth as a babies rear end. I've seen a few of those machines at some of the fabricators that actually can grind the welds as part of the process, and once painted you need to no what you're looking at to tell. But it can usually be determined simply by "size".
Here is why I think you're mistaken and the 10" high frame rail in your picture is a machine welded piece, and not a conventional hot rolled member. They make hot rolled H shapes (we call them a wide flange or W) or I shapes (A Jr / I, or S), only in specific readily availible sizes and weights. Going by your picture the flange width is roughly 2-1/2" wide. I determined that by comparison to the two fittings installed on the black tank. One is 1-1/2", the other 3".
There is no H or I which is hot rolled that a company like Lippert could buy from a hot mill, that would be those dimensions in a 10" height. It simply does not exist unless its a custom hot rolled shape and cost would not typically allow that.
In your picture you have a 10" height, a 2-1/2" flange width, and a 1/4" thickness both at flange and web based on the measurements you took.
Here is what you can get from a hot mill.
There are a couple dozen made with a 10" size in a wide flange, but none including the lightest which is a W10X12(lbs per ft), has a flange width smaller than 3.960 inches. Then they go up from there. The only size in a wide flange that has anywhere close to 1/4" average thickness at both flange and web is a W10X15, with a 4.00 flange width. The web is .230 and the flange is .269
There are only two readily available sizes in a Jr/I/S with a 10" height.
S10X25.4 or 10.000X4.661, The flange is 4.661 wide, and the thicknesses are flange .491 / web .311
S10X35 or 10.000X4.944, The flange is 4.944 wide, and the thicknesses are flange .491 / web .594
That's why I think your main rail is an engineered / fabricated / machine welded shape. That is unless Lippert is having hot rolled shapes custom made at great expense, or own a hot mill and making their own. Not sure why they would want to. The size is not available unless its fabricated. Maybe I'm wrong.
My Flanges are 2 3/4" wide, not 2 1/2"
And what you are stating is a but weld is not.
It is a cambering weld.
As for your other pic showing a person welding and stating he is not a robot... That is true. But it is also true that he is NOT welding a 3 piece I beam together.
I can find ZERO evidence that my frame is a so called welded I beam. And I have been into the underbelly for insulation, Heat tape and wiring upgrades.
If it were a welded I beam, and it was done so perfectly that it is impossible to tell by looking at it.... That would make it a pretty good one. IOW....Why gripe about it?- Look inside the tongue area for a sticker.
- From my AISC manual, a W10x15 has 1/4" web and flanges, but the flanges are 4" wide. That could be cut to width pretty easily with a plasma cutter though.
Ralph Cramden wrote:
Great info. and analysis!
Simply put there are two methods used to make a structural shape. Hot rolled or cold rolled. Specifically in relation to an H or I which are a complex shape, there are two ways to make them. Hot rolled is steel goes in one end of a plant, and an I or H comes out the other. Its then shipped to a fabricator who cuts it, drills it, fabricates it.
One thing I've noticed in the rolled beams is that in longer trailers, they aren't one continuous length. They're a couple of lengths with the ends butt welded together. It's done so well it's hard to see it and looks too good to be done by Lippert. Is there a maximum shipping length and it is actually done by Lippert or is it done by the supplier? These welds don't ever seem to be a problem and I would think are critical to be done properly. I've never seen or heard of a structural beam in a building not being one continuous length.
The 3-piece welded beams are usually on ultralite TTs and are easy to spot at an RV show or on a dealers lot by running a finger along the weld or looking it it. But just why do they use these beams? Are they lighter than an equivalent dimension rolled beam? I would expect a rolled beam would have a higher grade/strength for an equiv. dimension and maybe cost more per foot? But then the cost of welding 3 pieces of flat steel together to make a beam has to be costly and labor intensive. The 6" welded I-beams we had on a previous TT might as well have been made from rubber they flexed so much.
Cold rolled beams are hot rolled beams that undergo further processing and improves tolerances and appearance and would cost more so doubt they are used in any RV frames. Flat steel is hot rolled tho. and is what the welded beams would be made from (the finish is smoother on them). I don't think cold rolling improves the strength and any difference in strength would be from different grades of steel used.LVJJJ wrote:
Still have not heard if my Trail Cruiser is built on one, or how do you identify one?
In 2006 we bought a new 2007 RVision C21RBH TrailCruiser which we owned for a couple of seasons, eventually got rid of it because I hated having to deal with tenting but also because it was exhibiting a mold / mildew smell in the small front storage compartment and because the tires were wearing unevenly - perhaps an axle issue, perhaps a frame issue, I can't say. I don't recall who made the frame but if you own a 2005 it's a little late to be concerned about it now. ;)
