Frame is shot. We were going to leave tomorrow...

[redbarron55]

Here is an example of concentration stress and cracking especially starting at HAZ (heat affected Zones) .
The ideal would be to have the stress gradually spread over a wide area.
The reinforcement concentrated the stress on one place.
It looks like you can weld and I would suggest replacing the front of the frame.

[John in Santa Cruz]

Originally Posted by Stephen_Albers

Actually, your frame problem is quite common in small trailers. Their frames are not strong enough for boondocking. The internals rust from the inside out, like automobiles do. The frame flexing also often pops rivets and cracks shell moldings too.
Your first step is to decide if you are satisfied rolling down a paved highway from one over-priced RV slum to another or whether you want to boondock. Plan A requires a new factory frame. If boondocking is your goal, then your existing trailer can be seam welded unto a boondock frame that is strong enough to take the anticipated loads. This frame will also be corrosion-proofed internally to preclude rust. Specialty firms can build a boondock frame for you. If you want a referral, message me privately.

just curious, what range of costs for these sorts of custom frames?

[redbarron55]

I made the repairs and modifications to my Scamp without removing the whole floor (at that time, later I did replace the entire floor, adding fiberglass cloth epoxied top, bottom and sides)







[IMG]]https://www.fiberglassrv.com/forums/members/43511-albums1685-picture9772.jpg[/IMG]



Your problems are based on several things.
1. Lack of "fish" plates that spread the stress over a larger area than the HAZ.
2. Probably existing cracks in the bends and the carry through ends on either side of the door.
3. IF you boondock then this frame was never intended to do this. By the way, looking at the cracks there is little or no rust internally and even the edges are not very rusty, indicating that this crack at least is fairly new.

This and the other cracks are directly caused by the heat affected areas at the welds.
To prevent this "fish" plates need to be added to at least the sides of the frame and better all sides. If welded look carefully for undercutting and it is a good idea to "normalize" the weld area by heating to dull red with a "rosebud" gas welding tip.
I added a pretty heavy duty crossmember to help carry the loads from one side to the other and give a place to weld a little more structure for the front bath I added.





Look at the added bracing to the front of the carry through that makes the door opening. THIS is the area that starts the problems with flex and the attaching points cracking and adding to the flex. The flex here is what hastens the cracking at the bend on the driver's side.
On my trailer I added a second tube under the frame where the lower tube ends in front of the driver's side axle attach carrying it past the cross member and tapering it to the main frame (replaced). I did not add the closing plate like you did out of laziness.

Again, good luck.

[Mike Magee]

Originally Posted by Bryan L.

... I could also buy the Scamp frame and have someone local beef up the frame before install, although the original lasted over 25 years without too much issue so could just call it good...

So, the Scamp shells are good for maybe a hundred years, but the frames are good for 25... LOL


This reminds me of an old joke. The dentist tells he patient, "Sir, I have good news and bad news. The good news is, your teeth are fine! Unfortunately the gums will have to come out.

[ZachO]

I'll also apologize because I'm about to contribute to thread creep...

This isn't meant necessarily as a direct challenge, but...since when did the idea of our frames not being built to stand up to dirt roads become fact? Since just this thread? I've never heard this before but now it's being stated with confidence by two people.

I'm willing to accept that it's true, given some factual basis for the concept other than somebody just saying it. It's clear that frame issues are common, so I don't doubt this could be the case, but where does this info come from? I take my trailer down pretty crazy roads...either my frame is "better", or I'm about to start seeing these kinds of issues.

[WizWid]

Originally Posted by ZachO

I'll also apologize because I'm about to contribute to thread creep...

This isn't meant necessarily as a direct challenge, but...since when did the idea of our frames not being built to stand up to dirt roads become fact? Since just this thread? I've never heard this before but now it's being stated with confidence by two people.

I'm willing to accept that it's true, given some factual basis for the concept other than somebody just saying it. It's clear that frame issues are common, so I don't doubt this could be the case, but where does this info come from? I take my trailer down pretty crazy roads...either my frame is "better", or I'm about to start seeing these kinds of issues.

Most dirt roads are better than I10 across the South Coast. - so I have say it has no basis in fact.
Everything in moderation as your mother used to say......

[redbarron55]

Remember that the trailers that have frames cracking are older and many have a lot of miles on them.
There have been a fair number of owners report cracking and repairs here because they have found and repaired cracks in their frames and that is the only reason.
If an I mean IF the frame cracks it will be at the bends and on either side of the door.
The trailer does not have to be a dirt road boondocker either.
But many of these trailers are 25+ years old, but when the cracks were found they had been present for a while.

[Dan-NS27]

Yeah, door side on my frame was cracked and repaired with a fish plate. Driver side still looks good but I'm looking to replace the frame to something a little more sturdy.

[Bryan L.]

That's some nice work! I did pull out the front bench tonight to see what I'm working with. I'm not quite sure I have the skills to do what you did, (although an angle grinder can hide a lot of mistakes!) but I may try.

I was noticing the plates that had been welded on to yours in that exact same bend. This is too common a problem for Scamp to continue building like that, in my opinion. Thanks for the great pictures.

Originally Posted by redbarron55

I made the repairs and modifications to my Scamp without removing the whole floor (at that time, later I did replace the entire floor, adding fiberglass cloth epoxied top, bottom and sides)


Look at the added bracing to the front of the carry through that makes the door opening. THIS is the area that starts the problems with flex and the attaching points cracking and adding to the flex. The flex here is what hastens the cracking at the bend on the driver's side.
On my trailer I added a second tube under the frame where the lower tube ends in front of the driver's side axle attach carrying it past the cross member and tapering it to the main frame (replaced). I did not add the closing plate like you did out of laziness.

Again, good luck.

[Bryan L.]

This frame has seen mostly interstate at 75 mph in the eight years that I’ve owned it. I've done some sketchy roads here and there but just don't know what caused this issue.

Originally Posted by ZachO

I'll also apologize because I'm about to contribute to thread creep...

This isn't meant necessarily as a direct challenge, but...since when did the idea of our frames not being built to stand up to dirt roads become fact? Since just this thread? I've never heard this before but now it's being stated with confidence by two people.

I'm willing to accept that it's true, given some factual basis for the concept other than somebody just saying it. It's clear that frame issues are common, so I don't doubt this could be the case, but where does this info come from? I take my trailer down pretty crazy roads...either my frame is "better", or I'm about to start seeing these kinds of issues.

[k corbin]

Zak, you know what this is all about. It is about frustration, about looking for a bad guy to pin your troubles on.

It is simply human nature of anyone who has not been a student of physics and engineering to assume that the final event in a lifetime of stress on a structure must be the one and only contributing event that created the failure of the frame.

That dirt road broke my frame... yes indeed it did, along with thousands potholes in paved roads. Oh and what about those long stretches of highway under construction, washboard roads? And those high curbs you came off of? And years of rust?

Nope it was the dirt roads, they are the only cause, the rest of that stuff is just normal wear and tear, it never did the frame any harm.


That last straw was the only one responsible for breaking the camels back.

[redbarron55]

The thing that cracks the frame is the very slight bending that takes place at every little dip and wiggle.
The existence of a stress riser that concentrates the stress until there is a very very small crack that widens with every new dip, bump and wiggle until the member has a crack running through it.
The culprit is the millions of small bends in any long piece of metal especially at the already failed bend (done in manufacturing) where micro cracks probably already exist from the time the tube was bent to make the frame.
If the frame were painted and cured before bending you would probably see cracking in the paint t start with.
The metal is stretched on the outsides and where the tube is crimped and compressed on the inside.
This bend is the start of the failure. It is also unsupported and twists with every bounce and jiggle as well.
Failure is designed into this method of fabrication.

[ZachO]

Yes, it's all true.

I agree that these frames are not truck frames. While our trailers may be more built to last than some other designs, they still cut a lot of corners, or make compromises. It probably makes perfect sense for weight and for how most people use their trailers to keep the frame light-duty. Maybe that'll be a feature you can add on to some trailers in the future from the factory. Heavy duty frame.

It was definitely that last girlfriend, and her only, that gave me the gray hair though

[Mike Magee]

Originally Posted by ZachO

Yes, it's all true.
It was definitely that last girlfriend, and her only, that gave me the gray hair though

And you learned too late, since no new girlfriend can make that gray go away....

[ZachO]

I know!

I'm sure I'll find no sympathy here. It's only a few gray hairs, luckily. But I have officially started going gray.

[redbarron55]

Far better to turn gray than loose!