I was installing a receiver hitch and the bolt holes didn't quite line
up. The retailer advised me to check the alignment of the brackets that
bolt on to the frame and the passenger side bracket was bent in a
little. So with some effort I managed to bend it back mostly straight
and get the hitch installed. My question is would this minor bending
weaken the metal or the welded joints? It's a Draw-Tite hitch and I
think it's 1/4" plate steel brackets. How much can you bend something
like that without negatively affecting the structural properties?

TIA

"Bruce B" wrote in message
...
| I was installing a receiver hitch and the bolt holes didn't quite line
| up. The retailer advised me to check the alignment of the brackets that
| bolt on to the frame and the passenger side bracket was bent in a
| little. So with some effort I managed to bend it back mostly straight
| and get the hitch installed. My question is would this minor bending
| weaken the metal or the welded joints? It's a Draw-Tite hitch and I
| think it's 1/4" plate steel brackets. How much can you bend something
| like that without negatively affecting the structural properties?
|
| TIA

That concerns me that you, with effort, could bend a hitch frame.
However, whether or not that's a bad thing depends on how much of what you
bent, or preloaded, is in the critical load path.

carl mciver wrote:
"Bruce B" wrote in message
...
| I was installing a receiver hitch and the bolt holes didn't quite
line
| up. The retailer advised me to check the alignment of the brackets
that
| bolt on to the frame and the passenger side bracket was bent in a
| little. So with some effort I managed to bend it back mostly
straight
| and get the hitch installed. My question is would this minor
bending
| weaken the metal or the welded joints? It's a Draw-Tite hitch and I
| think it's 1/4" plate steel brackets. How much can you bend
something
| like that without negatively affecting the structural properties?
|
| TIA

That concerns me that you, with effort, could bend a hitch frame.
However, whether or not that's a bad thing depends on how much of
what you
bent, or preloaded, is in the critical load path.

He said he said he "managed to bend it back mostly straight".
He didn't mention the use of heat, so I would guess there was no loss
of any heat treatment related strength in the metal itself. It depends
on the bracket and its design, stresses, etc.
In reply to the OP, theoretically the metal has been taken past its
elastic limit when bent, and again when straightened... there is a
theoretical weakening, but I'd guess it is unlikely to be of any
practical consequence. As to the welds; they're usually (should be)
stronger than the parent metal, so you should have even less chance of
weakening the weld area.

wrote:
carl mciver wrote:

"Bruce B" wrote in message
...
| I was installing a receiver hitch and the bolt holes didn't quite

line

| up. The retailer advised me to check the alignment of the brackets

that

| bolt on to the frame and the passenger side bracket was bent in a
| little. So with some effort I managed to bend it back mostly

straight

| and get the hitch installed. My question is would this minor

bending

| weaken the metal or the welded joints? It's a Draw-Tite hitch and I
| think it's 1/4" plate steel brackets. How much can you bend

something

| like that without negatively affecting the structural properties?
|
| TIA

That concerns me that you, with effort, could bend a hitch frame.
However, whether or not that's a bad thing depends on how much of

what you

bent, or preloaded, is in the critical load path.


He said he said he "managed to bend it back mostly straight".
He didn't mention the use of heat, so I would guess there was no loss
of any heat treatment related strength in the metal itself. It depends
on the bracket and its design, stresses, etc.
In reply to the OP, theoretically the metal has been taken past its
elastic limit when bent, and again when straightened... there is a
theoretical weakening, but I'd guess it is unlikely to be of any
practical consequence. As to the welds; they're usually (should be)
stronger than the parent metal, so you should have even less chance of
weakening the weld area.

Thanks for the answers. No heat was used to bend it. This is what the
hitch looks like:
http://www.etrailer.com/productdetai... from=2003&h=e

The piece on the right that bolts to the vehicle was basically toed in
(probably less than an inch). I straightened it by bolting the passenger
side of the hitch to the driver's side of the vehicle so the hitch stuck
out to the side and then pulled it from the other end until I felt like
it moved. With that much leverage it wasn't too hard to bend but I did
have to put my weight into it. It was still a little difficult to bolt
up but I got it done. Later I started worrying about what stress this
might have caused to the metal and if it could have weakened it enough
to cause it to fail under load. I don't believe that it did but I wanted
to run it by the experts. I'm not sure but I think the piece that was
bent is 1/4" plate mild steel, which I think could take some minor
bending without issue???

"Bruce B" wrote in message
...
SNIP
| Thanks for the answers. No heat was used to bend it. This is what the
| hitch looks like:
|
http://www.etrailer.com/productdetai...=2381&year fr
om=2003&h=e
|
| The piece on the right that bolts to the vehicle was basically toed in
| (probably less than an inch). I straightened it by bolting the passenger
| side of the hitch to the driver's side of the vehicle so the hitch stuck
| out to the side and then pulled it from the other end until I felt like
| it moved. With that much leverage it wasn't too hard to bend but I did
| have to put my weight into it. It was still a little difficult to bolt
| up but I got it done. Later I started worrying about what stress this
| might have caused to the metal and if it could have weakened it enough
| to cause it to fail under load. I don't believe that it did but I wanted
| to run it by the experts. I'm not sure but I think the piece that was
| bent is 1/4" plate mild steel, which I think could take some minor
| bending without issue???

I'd say you're fine. What you've described seems to me to be well
within what I define as preload.

carl mciver wrote:
"Bruce B" wrote in message
...

SNIP

| Thanks for the answers. No heat was used to bend it. This is what the
| hitch looks like:
|
http://www.etrailer.com/productdetai...=2381&year fr
om=2003&h=e
|
| The piece on the right that bolts to the vehicle was basically toed in
| (probably less than an inch). I straightened it by bolting the passenger
| side of the hitch to the driver's side of the vehicle so the hitch stuck
| out to the side and then pulled it from the other end until I felt like
| it moved. With that much leverage it wasn't too hard to bend but I did
| have to put my weight into it. It was still a little difficult to bolt
| up but I got it done. Later I started worrying about what stress this
| might have caused to the metal and if it could have weakened it enough
| to cause it to fail under load. I don't believe that it did but I wanted
| to run it by the experts. I'm not sure but I think the piece that was
| bent is 1/4" plate mild steel, which I think could take some minor
| bending without issue???

I'd say you're fine. What you've described seems to me to be well
within what I define as preload.

Thanks much.

"carl mciver" wrote in message
nk.net...
"Bruce B" wrote in message
...
|
| The piece on the right that bolts to the vehicle was basically toed
| in (probably less than an inch). I straightened it by bolting the
| passenger side of the hitch to the driver's side of the vehicle so
| the hitch stuck out to the side and then pulled it from the other
| end until I felt like it moved. With that much leverage it wasn't
| too hard to bend but I did have to put my weight into it.

I'd say you're fine. What you've described seems to me to be well
within what I define as preload.


Preload is elastic deformation ONLY (i.e., the "spring" in metal; it would
return to it's previous shape if the load is removed). Since Bruce actually
bent the metal, it experienced plastic deformation (i.e., the metal was
permanently deformed), which is no longer in the realm of "preload".

That said, I don't think there will be a problem. The biggest problem Bruce
would have to worry about would be metal fatigue if the part was repeatedly
bent. I suspect this will not occur once the hitch is bolted tight to the
frame.

But I am curious why Bruce didn't return the obviously defective hitch.

- Michael

DeepDiver wrote:
Preload is elastic deformation ONLY (i.e., the "spring" in metal; it
would
return to it's previous shape if the load is removed). Since Bruce actually
bent the metal, it experienced plastic deformation (i.e., the metal was
permanently deformed), which is no longer in the realm of "preload".

That said, I don't think there will be a problem. The biggest problem Bruce
would have to worry about would be metal fatigue if the part was repeatedly
bent. I suspect this will not occur once the hitch is bolted tight to the
frame.

But I am curious why Bruce didn't return the obviously defective hitch.

I was going to return it but when I called the retailer it sounded as if
this wasn't uncommon. Though I can't imagine why a manufacturer wouldn't
correct this if it was common. I didn't even know it was bent until the
guy I talked to told me what to look for and how to fix it. It was
ordered so shipping back and forth would have been quite a hassle and
fixing it seemed like the best option. Stressing the metal didn't occur
to me until later but I think it will be fine. Everyone I've asked so
far didn't think there would be any problem. It is bolted in place and
won't be bent any further.

Bruce B wrote:
Though I can't imagine why a manufacturer wouldn't correct this if it was common.

Because if it costs money today, most manufacturers don't want to do it. "Let the next
management group deal with my failures tomorrow or let the former customer sue my now defunct
business"

As long as you didn't in fact bend the car/truck to match the
receiver...
It COULD happen, depending on the frame/sub-frame, e.g. a unibody or
flimsy sub frame might give before the hitch bracket. OTOH, a full
sized truck probably has enough steel to act as a good anchor to permit
being bent against.

In my understanding of your problem, you're just experiencing a move of
the metal on the horizontal plane, not the vertical plane. Since the
load on the hitch should be on the vertical plane (by and large) any
stressing and loss of capacity on the vertical plane via the adjustment
on the horizontal plane should be minimal. There might be some
discussion as to whether or not you bent the frame of the hitch at the
base of the legs that run front-to-rear of the vehicle or if you bent
them at some mid-point. I would say this to you, whatever stresses you
have applied to the material are along the horizontal plane where load
is less applied by the towed unit than if it was vertical plane.
Furthermore, these things are manufactured with a certain tolerance;
e.g. if the hitch is capable of handling 500 Lbs. tongue weight it
won't FAIL at 500 pounds, it might fail at 700 or 800 pounds; 500 is
just the "rated capacity"; i.e. what it can handle safely. So, 1) you
have some room on the numbers to play with and 2) we're talking failure
at maximums; if the hitch you installed is a Class III or whatever that
might only be rated for 300 pounds tongue weight (rated, not *failure
weight* and all you ever do is haul around a law mower trailer that
tops out at 180 pounds tongue weight then, you're fine.

Ultimately you have to do what you feel best with. Even as picky as I
am, I'd not sweat it.

Seriously, I sweat the details (and it works well for me), but this
sounds like you're being obsessively obsessive. It'll be fine You
think not, take a trip to some rural areas and see what the yahoo's are
using to tow stuff.

--HC

HC wrote:
In my understanding of your problem, you're just experiencing a move of
the metal on the horizontal plane, not the vertical plane. Since the
load on the hitch should be on the vertical plane (by and large) any
stressing and loss of capacity on the vertical plane via the adjustment
on the horizontal plane should be minimal. There might be some
discussion as to whether or not you bent the frame of the hitch at the
base of the legs that run front-to-rear of the vehicle or if you bent
them at some mid-point. I would say this to you, whatever stresses you
have applied to the material are along the horizontal plane where load
is less applied by the towed unit than if it was vertical plane.
Furthermore, these things are manufactured with a certain tolerance;
e.g. if the hitch is capable of handling 500 Lbs. tongue weight it
won't FAIL at 500 pounds, it might fail at 700 or 800 pounds; 500 is
just the "rated capacity"; i.e. what it can handle safely. So, 1) you
have some room on the numbers to play with and 2) we're talking failure
at maximums; if the hitch you installed is a Class III or whatever that
might only be rated for 300 pounds tongue weight (rated, not *failure
weight* and all you ever do is haul around a law mower trailer that
tops out at 180 pounds tongue weight then, you're fine.

Ultimately you have to do what you feel best with. Even as picky as I
am, I'd not sweat it.

Seriously, I sweat the details (and it works well for me), but this
sounds like you're being obsessively obsessive. It'll be fine You
think not, take a trip to some rural areas and see what the yahoo's are
using to tow stuff.

--HC


You're right, I tend to be overly obsessive. Thanks for your answer. It
was bent only in the horizontal plane and the main piece that runs
across the back of the vehicle was not bent at all. Just the bracket
that bolts to the vehicle and it wasn't really a noticeable bend. I
think I'll let it go and move on to the next thing to obsess over ;-)