All frames flex

Wayne

Wayne

Administrator
Staff member
This crack in the wall started after about 10k miles pulling our trailer around the country. New Horizons builds their own chassis and they are stronger and heavier than any other RV frame. Every used New Horizons I've looked at has the same crack on the drivers side where the wall is narrow.

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You'd almost think they might handle it sortof like concrete. Pre-cut a slice through it and seal it.
 
Azjeff said:
Something different in the frame bracing? N/H has to be aware of it.
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Yes, NH is aware, all of their trailers skin cracks in the same place. They said they could make the frame stiffer, but they would have to add strength elsewhere. The frame needs to flex a bit or it would cause frame cracking somewhere else...
 
MSCH said:
definitely... and if that tape wont fix it this stuff definitely will. fast FWD to about the 45 second mark. ( FWIW got the be my favorite commercial ever)
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Why even bother with a roof membrane when we could go straight to Flex Shot?
 
Azjeff said:
I've been thinking of using 12" Eternabond tape to do the roof.
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I've read good and bad about using that to seal all the seams. Last I looked into it, it works great, but if/when it fails it is a nightmare to remove and redo.
 
I used it to seal the bubble skylights on an A-frame pop-up we had for a short time. It does work great and it seems the way to get it off is use heat to remove the top tape layer then more heat to soften the goo and scrape it off then use some solvent or just retape. Sold that pop-up long before I had to redo any tape.
 
Not serious about the 12" Eternabond. Hope this trailer is gone before a roof replacement is needed.
 
Azjeff said:
Not serious about the 12" Eternabond. Hope this trailer is gone before a roof replacement is needed.
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I'm pretty much on my last trailer.. I'm going to use the heck out of the Bighorn and next step is going to be to buy a vacation house somewhere up north... because I am going to do a reverse snowbird thing, go up north in the summer and drive slow..
 
Just watched a video by All About RVs about frame flex. Blown away by how the front overhang is attached on his Grand Design. Skip to 4:00 and see what he finds. At 6:00 you can see what is supposed to keep it all together, a lag into a bit of wood inside the thin wall tubing framework of the sidewall. Incredible. This guy is local to us but haven't run across him yet.
 
I found some pictures of our trailer frame after is was painted. You can see how New Horizons builds these chassis. They are very heavy duty.

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This shows the size of the gusset that spreads the stress out on the down post.

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when I look at any RV, first thing I think is how weak the frame looks in the area going up to the gooseneck..to me it doesn't look all that heavy duty... I doubt there is much done in the way of engineering and testing either.. one of those we have always done it this way..and we get away with it things.

compare it to a standard gooseneck...

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MSCH said:
when I look at any RV, first thing I think is how weak the frame looks in the area going up to the gooseneck..to me it doesn't look all that heavy duty... I doubt there is much done in the way of engineering and testing either.. one of those we have always done it this way..and we get away with it things.

compare it to a standard gooseneck...
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I talked to New Horizons about this design and questioned the strength. They told me that yes an engineering firm validated the design and the same design is used for their largest trailers, which weigh about 25k lbs empty. They have never had one crack. I believe the key is that the box spreads the stress out over much more distance than the standard gooseneck trailer.

The frame box beams are 8" with 1/4" walls and the I-beams are 12" webs with 1/4" thickness. These are not lightweight and certainly much heavier than what is normally used in the RV industry. The downside is that the frames are very heavy.

A couple more pictures of the design.

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Troy - he's the head welder, been making frames his entire career. Great guy.
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