Billy,
I think you are referring to this video.
http://dtu.ifh.dk/Jokes/Film/web/snowtowcar.mpg.html

Tom

"billy ray" wrote in message
...
Who has the video of a rear bumper being ripped off while attempting to
pull
another vehicle out of the snow alongside the road?

I saw a link to it sometime in the last 6 months or so...

"cantrelm" wrote in message
.. .
Billy,
I think you are referring to this video.
http://dtu.ifh.dk/Jokes/Film/web/snowtowcar.mpg.html

This one's funny...
http://dtu.ifh.dk/Jokes/Film/web/topbike.mpeg.html

Well.... there is no Jeep in that one but it is a good illustration on the
strength of bumper supports..


"cantrelm" wrote in message
.. .
Billy,
I think you are referring to this video.
http://dtu.ifh.dk/Jokes/Film/web/snowtowcar.mpg.html

Tom

"billy ray" wrote in message
...
Who has the video of a rear bumper being ripped off while attempting to
pull
another vehicle out of the snow alongside the road?

I saw a link to it sometime in the last 6 months or so...

Richard J Kinch wrote:
Andrew VK3BFA writes:

could I
humbly suggest that a sticker saying "max towing weight 1,000lbs" be
put on the thing?

If it ever came down to a situation where someone would read it, and heed
it, then I might do something like that. For my personal use, why bother.
(On the other hand, I've never had much use for that steel punch stamping
kit, maybe I'll stamp it on there for that Canadian trip someday, heh heh.)

*******sigh******** I'm probably ****ing into the wind on this one, but
here goes anyway. Why not just do it, cover the situation where
"Someone Else" might be tempted to overload it. This is called
engineering. Plan for the worse.

This whole culture of Jeep hitches has me baffled. People insist on
putting class III hitches on a short-wheelbase soft-top vehicle that
dubiously purports even a minimal 2000 lb capacity. The guys who also have
the jacked-up suspensions, cheating death with their unstable aftermarket
mods, are the extreme version of this.

The rev head culture amazes me too sometimes. Driving to the local
shops in a 2 ton 4wd vehicle fitted out to blast through the Amazon
Jungle defies logic. But as long as they dont do anything to kill me,
they are welcome to it. So, by your logic, refusing to take even
minimal precautions against misuse is OK because "other people" do even
more stupid things. Do you write software this way?

THere is a kind of "impedance matching" optimization to this type of
design, and I believe I've approximated it for the intended application.

Written by a true, tunnel vision, engineer. A pity that the rest of
the world doesnt, or cant think like this.

Richard, you posted the design on this group. People responded. You
negate any feedback you receive. They are not personal attacks - at
least, not until you started responding in a silly manner.

One of the beginnings of maturity is recognising how little you know as
an individual. Intelligence is then finding the information you need to
overcome this. It is not just "Jeep trailer hitches" - its for the rest
of your life, and your life to date, as well. Think about this -
please - your life might start to get better and less confrontational.

Anderw VK3BFA.

Andrew VK3BFA writes:

Why not just do it, cover the situation where
"Someone Else" might be tempted to overload it. This is called
engineering. Plan for the worse.

I am an engineer.

I define engineering as the economical application of scientific
knowledge to a physical application.

To "plan for the worse" is not engineering, if the worst is not worth
planning for. It is spending too much on the biggest and baddest in the
catalog, which is the anti-engineering mentality of "I built it as
strong as possible, so I didn't have to think about it, nothing more
could have been done". You don't build a wooden crate when a cardboard
box will do, even though it won't stand up to a gorilla jumping on it.

Look, the item tows my boat, economically, and with some material
analysis, albeit casual. It does not fit the worst case, nor is it
intended to.

One of the beginnings of maturity is recognising how little you know
as an individual.

Ya gotta love Usenet. Posters simulating critical thought with
platitudes, without knowing who they are talking to.

Grumman-581 writes:

One thing that I noticed that I would at least re-engineer a bit was the
fact that it appears that his hitch plate does not have a backing plate
...

A (smaller) backing plate is only a glorified washer, good only against
shearing through the attachment point. The rest of the bumper will have
failed before that happens, so it adds nothing.

A larger backing plate would be tantamount to replacing the bumper with a
stronger cross-member, and at that point you might as well put on a frame-
mounted hitch instead of using the bumper.

Richard,

I like your definition of engineering. I guess I am a successful engineer,
because I worked for exactly six years, three months after I got out of
school, and I have been retired for eleven years since. I call that "the
economical application of scientific knowledge to a physical application".
Sure I could have worked for twice as long, had a couple heart attacks, and
there would be enough money for my widow, kids and grandkids to never have
to be afraid of poverty or hunger again. There is a parallel here, and
someday I am going to figure out what it is. Until then, you keep doing
what you are doing.

"Posters simulating critical thought with platitudes", I love this. Please
feel free to post here again, the next time you engineer something. ;^)

Earle

"Richard J Kinch" wrote in message
. ..
Andrew VK3BFA writes:

Why not just do it, cover the situation where
"Someone Else" might be tempted to overload it. This is called
engineering. Plan for the worse.

I am an engineer.

I define engineering as the economical application of scientific
knowledge to a physical application.

To "plan for the worse" is not engineering, if the worst is not worth
planning for. It is spending too much on the biggest and baddest in the
catalog, which is the anti-engineering mentality of "I built it as
strong as possible, so I didn't have to think about it, nothing more
could have been done". You don't build a wooden crate when a cardboard
box will do, even though it won't stand up to a gorilla jumping on it.

Look, the item tows my boat, economically, and with some material
analysis, albeit casual. It does not fit the worst case, nor is it
intended to.

One of the beginnings of maturity is recognising how little you know
as an individual.

Ya gotta love Usenet. Posters simulating critical thought with
platitudes, without knowing who they are talking to.

Richard J Kinch wrote:
Andrew VK3BFA writes:

Why not just do it, cover the situation where
"Someone Else" might be tempted to overload it. This is called
engineering. Plan for the worse.

I am an engineer.

I define engineering as the economical application of scientific
knowledge to a physical application.

Nah. Thats cost accounting. Design and manufacture something with the
minimal cost and effort that will just do the job with no margin for
error. When it fails, refer to "Definition of Engineering" and blame
the customer for their lack of knowledge.



One of the beginnings of maturity is recognising how little you know
as an individual.

Ya gotta love Usenet. Posters simulating critical thought with
platitudes, without knowing who they are talking to.

Sorry, wasnt aware I was talking to "an engineer". I apologise. Please
forgive me for my ignorant comments.

Andrew VK3BFA.

If you get in an accident and someone gets hurt.
only then, is when it really counts. You may get charged.
I've seen hitches like yours and it was bent all to hell.
Don't be stupid/cheap, pay the 150 fricken dollars for a proper hitch
and be safe! This is NOT Microsoft where failures are sorta O.K.
Dag nab it.

Andrew VK3BFA writes:


Why not just do it, cover the situation where
"Someone Else" might be tempted to overload it. This is called
engineering. Plan for the worse.


I am an engineer.

I define engineering as the economical application of scientific
knowledge to a physical application.

To "plan for the worse" is not engineering, if the worst is not worth
planning for. It is spending too much on the biggest and baddest in the
catalog, which is the anti-engineering mentality of "I built it as
strong as possible, so I didn't have to think about it, nothing more
could have been done". You don't build a wooden crate when a cardboard
box will do, even though it won't stand up to a gorilla jumping on it.

Look, the item tows my boat, economically, and with some material
analysis, albeit casual. It does not fit the worst case, nor is it
intended to.


One of the beginnings of maturity is recognising how little you know
as an individual.


Ya gotta love Usenet. Posters simulating critical thought with
platitudes, without knowing who they are talking to.

FrankW writes:

You may get charged.

Debunked earlier in this thread.

Richard J Kinch wrote:

FrankW writes:

You may get charged.

Debunked earlier in this thread.

Ok, now you are just being plain stupid sir.

You can be 'sure' if something happens and that home made hitch lets go
and your trailer goes off and kills someone you will be charged.

Even in good ol Florida.

Your 'debunk' said nothing at all and I looked.

It was a BS smokescreen link that didn't cover the law about the
structure of the attachment point or cover carrying a load too big for
the hitch or vehicle.

Mike
86/00 CJ7 Laredo, 33x9.5 BFG Muds, 'glass nose to tail in '00
88 Cherokee 235 BFG AT's
Canadian Off Road Trips Photos: Non members can still view!
Jan/06 http://www.imagestation.com/album/pi...?id=2115147590
(More Off Road album links at bottom of the view page)

Richard J Kinch proclaimed:

FrankW writes:


You may get charged.


Debunked earlier in this thread.

Rebunked. And even more happy instance, you can have your heinie sued
off even if you weren't cited for excessive carelessness and wanton
stupidity.

Mike Romain writes:

You can be 'sure' if something happens and that home made hitch lets go
and your trailer goes off and kills someone you will be charged.

Still bunk.

Simply driving, nothing is going to "happen" with this hitch. In a
collision, the violation and/or liability is with the driver at fault for
the collision. Not with the hitch or its owner.

"Home made" has *nothing* to do with it.

Read the law. I cited it earlier. Florida makes absolutely no specific
technical requirements for hitches, only that you have "sufficient strength
to pull all weight towed" and that you have safety chains or other 49 CFR
devices. You can tow with overcooked spaghetti if it has "sufficient
strength".

People tow cars with rope and granny knots every day. Nothing illegal about
it.

Thank God I live in Georgia, and it is illegal to tow with " ropes an granny
knots ". Up here you get ticketed for not have a proper hitch. Just goes
to show you that the Transplanted Yankees in Florida have had there brains
fried too long out in all that sun!!!!

Richard being as how you have a Ph.D. I am going to assume you know the
difference between ignorant and stupid. Well you can't say that you are
ignorant, as too many people in here have tried to educate you on this
matter, so what choice does that leave us with to describe you?

Tom


"Richard J Kinch" wrote in message
. ..
Mike Romain writes:

You can be 'sure' if something happens and that home made hitch lets go
and your trailer goes off and kills someone you will be charged.

Still bunk.

Simply driving, nothing is going to "happen" with this hitch. In a
collision, the violation and/or liability is with the driver at fault for
the collision. Not with the hitch or its owner.

"Home made" has *nothing* to do with it.

Read the law. I cited it earlier. Florida makes absolutely no specific
technical requirements for hitches, only that you have "sufficient
strength
to pull all weight towed" and that you have safety chains or other 49 CFR
devices. You can tow with overcooked spaghetti if it has "sufficient
strength".

People tow cars with rope and granny knots every day. Nothing illegal
about
it.

On Mon, 30 Jan 2006 20:12:12 -0800, Lon
wrote:
Richard J Kinch proclaimed:
FrankW writes:

You may get charged.

Debunked earlier in this thread.

Rebunked. And even more happy instance, you can have your heinie sued
off even if you weren't cited for excessive carelessness and wanton
stupidity.

Rebunked agreed - There's nothing wrong with the design of the hitch
plate you made itself, it looks plenty strong for the intended
purpose, but the structural integrity of the bumper you /attached it
to/ is a complete unknown.

Since the Feds stopped requiring bumpers to survive 2-1/2 and 5 MPH
crash tests car and light truck bumpers are pretty much beauty items
only, and some (especially the ones not designed as a trailer hitch)
are virtually stamped from tissue paper and then chromed. You
admitted it yourself that they're made to crumple - and you can't
count on strength in towing from a known weak structure.

I would strongly suggest you go get a proper receiver hitch made
that is tucked under the car, and remove the drawbar whenever you
aren't using it - and if you do get hit in the rear, that tissue paper
bumper will be the item hanging out there to get hit and try to absorb
the forces. (Not.) But hey, it's your liability, not mine.

Nothing will likely happen to you legally now, the cops don't go
around inspecting people's trailer hitches on a whim - until the hitch
fails.

If and when it fails while on a public street or highway, and the
trailer wanders off and kills someone or does some serious property
damage, they are going to send out an officer (local or state,
depending) to investigate and write the reports. And if the LEO sees
a mangled mess on the back of the car that let go, they'll probably
(as the old saw goes) "throw the book at you".

The Officers can easily reconstruct the accident scene - there are
trained Major Accident Investigation Teams that do nothing but this,
every day. They figure how fast everyone was going, do the math on
the forces involved on the bumper in the accident, and prove that the
weak link was the hitch that let go. They can prove that a properly
designed hitch would have held under 2X to 4X (or more) of the forces
involved in that incident - so whoever made that hitch is at fault.

In California, this would be one of the brickbats in said book:

http://www.dmv.ca.gov/pubs/vctop/d13/vc29003.htm

Hitch, Coupling Device or Connection, or Tow Dolly

29003. (a) Every hitch or coupling device used as a means of
attaching the towed and towing vehicles shall be properly and
securely mounted and be structurally adequate for the weight
drawn. The mounting of the hitch or coupling device on the
towing and towed vehicle shall include sufficient reinforcement
or bracing of the frame to provide sufficient strength and
rigidity to prevent undue distortion of the frame.

(b) The drawbar, tongue, or other connection between the towing
and towed vehicles shall be securely attached and structurally
adequate for the weight drawn.

(c) The raised end of any motor vehicle being transported by
another motor vehicle using a tow dolly shall be secured to
the tow dolly by two separate chains, cables, or equivalent
devices adequate to prevent shifting or separation of the
towed vehicle and the tow dolly.

Amended Ch. 708, Stats. 1983. Effective January 1, 1984.

Yes, you are in Florida - but most vehicle codes are similar.

-- Bruce --
--
Bruce L. Bergman, Woodland Hills (Los Angeles) CA - Desktop
Electrician for Westend Electric - CA726700
5737 Kanan Rd. #359, Agoura CA 91301 (818) 889-9545
Spamtrapped address: Remove the python and the invalid, and use a net.

cantrelm writes:

... people in here have tried to educate you on this matter ...

They have educated me as to their casual opinions in conflict with concrete
experience. Normal Usenet flux.

I'd be surprised if as you assert Georgia doesn't allow towing with rope.
But I couldn't find the relevant statute, maybe you can:

http://www.legis.state.ga.us/cgi-bin/gl_codes_detail.pl

The link below is to a page in the Florida Fish and Wildlife
Conservation website. I will assume, with the known limitations therein,
that it may be taken as an 'official" publication

Please see paragraphs 4 & 5 in section 1
Please see paragraph 5 in section 2
Please see illustration 2
http://www.boat-ed.com/fl/course/p2-4_trailering.htm

You hitch design may be legal in Florida.... assuming that you can get the
data from the DC engineering departments for "the weight rating of the
bumper. "

However the factory manual shows the only approved (by DC) methods of
attaching a towbar. In my XJ manual it is section 13 pages 7 & 8.

Does someone have a Wrangler manual that can check and post the appropriate
pages in the Frames & Bumpers section?


"Richard J Kinch" wrote in message
. ..
cantrelm writes:

... people in here have tried to educate you on this matter ...

They have educated me as to their casual opinions in conflict with
concrete
experience. Normal Usenet flux.

I'd be surprised if as you assert Georgia doesn't allow towing with rope.
But I couldn't find the relevant statute, maybe you can:

http://www.legis.state.ga.us/cgi-bin/gl_codes_detail.pl

I agree fully with Bruce.
The 3/8" x 4" angle is plenty sturdy enough. That is not what everyone is
complaining about. It is the 3/32" sheet you have attached it too that is
not strong enough for a load.....Remember that a chain is only as strong as
its weakest link and the weakest link hear is the 3/32" stock bumper!

But hey that is okay..... I just hope you sleep well after that bumper rips
through and your trailer and angle hitch go veering off and hurt
someone......

Get over yourself and stop being such a cheapskate! You seem to take pride
in your cheapness and stupidity.......

Tom


"Bruce L. Bergman" wrote in message
news
On Mon, 30 Jan 2006 20:12:12 -0800, Lon
wrote:
Richard J Kinch proclaimed:
FrankW writes:

You may get charged.

Debunked earlier in this thread.

Rebunked. And even more happy instance, you can have your heinie sued
off even if you weren't cited for excessive carelessness and wanton
stupidity.

Rebunked agreed - There's nothing wrong with the design of the hitch
plate you made itself, it looks plenty strong for the intended
purpose, but the structural integrity of the bumper you /attached it
to/ is a complete unknown.

Since the Feds stopped requiring bumpers to survive 2-1/2 and 5 MPH
crash tests car and light truck bumpers are pretty much beauty items
only, and some (especially the ones not designed as a trailer hitch)
are virtually stamped from tissue paper and then chromed. You
admitted it yourself that they're made to crumple - and you can't
count on strength in towing from a known weak structure.

I would strongly suggest you go get a proper receiver hitch made
that is tucked under the car, and remove the drawbar whenever you
aren't using it - and if you do get hit in the rear, that tissue paper
bumper will be the item hanging out there to get hit and try to absorb
the forces. (Not.) But hey, it's your liability, not mine.

Nothing will likely happen to you legally now, the cops don't go
around inspecting people's trailer hitches on a whim - until the hitch
fails.

If and when it fails while on a public street or highway, and the
trailer wanders off and kills someone or does some serious property
damage, they are going to send out an officer (local or state,
depending) to investigate and write the reports. And if the LEO sees
a mangled mess on the back of the car that let go, they'll probably
(as the old saw goes) "throw the book at you".

The Officers can easily reconstruct the accident scene - there are
trained Major Accident Investigation Teams that do nothing but this,
every day. They figure how fast everyone was going, do the math on
the forces involved on the bumper in the accident, and prove that the
weak link was the hitch that let go. They can prove that a properly
designed hitch would have held under 2X to 4X (or more) of the forces
involved in that incident - so whoever made that hitch is at fault.

In California, this would be one of the brickbats in said book:

http://www.dmv.ca.gov/pubs/vctop/d13/vc29003.htm

Hitch, Coupling Device or Connection, or Tow Dolly

29003. (a) Every hitch or coupling device used as a means of
attaching the towed and towing vehicles shall be properly and
securely mounted and be structurally adequate for the weight
drawn. The mounting of the hitch or coupling device on the
towing and towed vehicle shall include sufficient reinforcement
or bracing of the frame to provide sufficient strength and
rigidity to prevent undue distortion of the frame.

(b) The drawbar, tongue, or other connection between the towing
and towed vehicles shall be securely attached and structurally
adequate for the weight drawn.

(c) The raised end of any motor vehicle being transported by
another motor vehicle using a tow dolly shall be secured to
the tow dolly by two separate chains, cables, or equivalent
devices adequate to prevent shifting or separation of the
towed vehicle and the tow dolly.

Amended Ch. 708, Stats. 1983. Effective January 1, 1984.

Yes, you are in Florida - but most vehicle codes are similar.

-- Bruce --
--
Bruce L. Bergman, Woodland Hills (Los Angeles) CA - Desktop
Electrician for Westend Electric - CA726700
5737 Kanan Rd. #359, Agoura CA 91301 (818) 889-9545
Spamtrapped address: Remove the python and the invalid, and use a net.

Richard,

I will respect that you have made all the proper calculations on your boat
and trailer weights and have for your education know the strength parameters
and limitations of the Jeep Wrangler bumper attachment system.

That being said many of the people replying to you have years or decades of
practical experience and many, myself included, have seen vehicles with
their rear bumpers twisted or pulled off by what they were towing.

Imagine, if you will, a scene we all hope will never happen where you are in
a courtroom with your spreadsheet defending your calculations and
workmanship. The county prosecutor then calls a representative from Reese,
Hidden Hitch, Valley, etc and asks them to display all the hitches they
manufacture that fit the Wrangler.

The will come in on carts, of course, as they weigh in at 20+ pounds. The
drawbars themselves are 3/4 inch steel the crossbars 1.25 or 2 inch steel
pipe or tube, and the attachment plates while only 1/4 inch thick are 4-6
inches wide and attached by 1/2 inch grade 5 or 8 bolts. He will then pick
up what is left of your bumper and twist it in his bare hands.

Are you wrong in an engineering point of view? No, but the jury is going to
send you to prison anyway because they won't understand why the industry
standard is 10x and yours wasn't.

Then you get to go home and explain, again, to your bride why her youngest
child died. All the spreadsheets in the world won't convince her it was
unforeseeable and unpreventable..

Please do not let your professional pride prevent you from installing a
hitch that is vastly in excess of your requirements. There are 6 listed on
eBay at this moment with bids of less than $30. (search term: Wrangler
hitch)

"Richard J Kinch" wrote in message
. ..
cantrelm writes:

... people in here have tried to educate you on this matter ...

They have educated me as to their casual opinions in conflict with
concrete
experience. Normal Usenet flux.

I'd be surprised if as you assert Georgia doesn't allow towing with rope.
But I couldn't find the relevant statute, maybe you can:

http://www.legis.state.ga.us/cgi-bin/gl_codes_detail.pl

Jeep Wrangler Owners Manual.

I have one and it states:

"Trailer Towing Requirements:
Class I Hitch (Light Duty) for towing trailers with a Gross Trailer Weight
of up to and not exceeding 2,000 lbs. (907kg).
2.5L, engine with 5-speed Manual or any 4.0L engine / transmission
combination.
CAUTION!
Do not use a bumper mounted clamp-on tow bar on your vehicle. The bumper
face bar will be damaged."

Nuff said!

Tom



"billy ray" wrote in message
...
The link below is to a page in the Florida Fish and Wildlife
Conservation website. I will assume, with the known limitations therein,
that it may be taken as an 'official" publication

Please see paragraphs 4 & 5 in section 1
Please see paragraph 5 in section 2
Please see illustration 2
http://www.boat-ed.com/fl/course/p2-4_trailering.htm

You hitch design may be legal in Florida.... assuming that you can get the
data from the DC engineering departments for "the weight rating of the
bumper. "

However the factory manual shows the only approved (by DC) methods of
attaching a towbar. In my XJ manual it is section 13 pages 7 & 8.

Does someone have a Wrangler manual that can check and post the
appropriate
pages in the Frames & Bumpers section?

Nobody will claim you need 1/2" steel for your hitch. However, engineering
is usually about designing in safety margins to ensure people don't get
hurt. Your tyres are engineered to take a much greater load than is applied
by your Jeep, for example.

So the rest is philosophy ; given it won't fall off in an ideal situation -
how much of a safety margin are you prepared to begrudgingly spend your
cents on ? I guess the answer is "less than anyone else".

Dave Milne, Scotland
'91 Grand Wagoneer, '99 TJ

"Richard J Kinch" wrote in message
. ..
I am an engineer.

I define engineering as the economical application of scientific
knowledge to a physical application.

To "plan for the worse" is not engineering, if the worst is not worth
planning for.

billy ray writes:

No, but the jury is going to
send you to prison anyway because they won't understand why the industry
standard is 10x and yours wasn't.

Nonsense. FS 316.530 is a "noncriminal traffic infraction."

Yeah, horrible accidents happen. The weak-hitch-equals-death analysis
makes a pleasant fictional scene, but unconvincing as to reality.

Bruce L. Bergman writes:

They figure how fast everyone was going, do the math on
the forces involved on the bumper in the accident, and prove that the
weak link was the hitch that let go. They can prove that a properly
designed hitch would have held under 2X to 4X (or more) of the forces
involved in that incident - so whoever made that hitch is at fault.

Baloney.

The (Florida) law requires a hitch to be of "sufficient strength to pull
all weight towed thereby". There is no "proper design" beyond that. The
performance in a *collision* is of no legal significance. The liability is
strictly with the at-fault driver(s).

By your "proper design" theory, you could be sued for driving a Hyundai
instead of a Humvee. It's your fault you got hurt riding in a tinfoil car,
not that somebody rear-ended you.

You can beef up your vehicle to take a meteorite hit, but it will be no
more or less liability in a collision.

Richard,
I also note upon looking at the setup again, that the safety chains would
attach to the same piece of metal that the hitch resides upon. If the weak
link here is the strength of the bumper material, having the chains attached
to the frame will help.

A while back in the thread, Mike painted a scenario where you might be
rear-ended and the trailer tongue shoots through the Jeep's tub. I have
actually had this happen to me. I have a pop-up camper towed by a Sienna.
While waiting to make a left turn, a van hit the back of the trailer hard.
Both the other van and the trailer were totaled. The tongue was indeed
pushed into the back of the Sienna and the force vector was straight in line
with the car's direction and also upward a bit. The upward tilt of the
hitch ball surprised me a bit, but there it was. I had to unbolt the whole
hitch and drop it to disconnect the trailer from the ball, as it was buried
up in the upper bumper. The combination of the Class 2 hitch and then the
frame of the Sienna absorbed it all, about $2500 worth of fixed damage to
the Sienna. I speculate that if I had an equivalent of this hitch design,
it would be likely that the trailer tongue would, in its upward vector,
pierce the rear of the tub and head for people in the seats.

At least safety chains attached to the frame instead of the part that is
(connected to at least) part of the failure might mitigate this. The chains
need to be of plenty of girth as well.

In other words, if the bumper is the weak point, and the chains are attached
to the metal attached to the bumper, the chains provide zero additional
help. They would only help if the trailer jumps off of the ball. I
advocate attaching them to the frame.
Tomes


"Richard J Kinch" wrote in message
. ..
Here is my design for a bumper-mounted Jeep Wrangler TJ trailer hitch:

http://www.truetex.com/jeep_trailer_hitch_bracket.htm

You aren't likely to convince him. He 'thinks' he is edUcated so he
knows better.

I had some short blond in a large pickup ram into my utility trailer 3
times at a red light before I got out to see what the hell she was
doing. She was so short, she couldn't see the trailer and just couldn't
understand why she couldn't get closer to me.

That one wrecked a 'legal' trailer hitch and the tongue spear also
wanted to come up over the bumper. My bumper was a 'real' one so the
tongue didn't punch through it.

Mike
86/00 CJ7 Laredo, 33x9.5 BFG Muds, 'glass nose to tail in '00
88 Cherokee 235 BFG AT's
Canadian Off Road Trips Photos: Non members can still view!
Jan/06 http://www.imagestation.com/album/pi...?id=2115147590
(More Off Road album links at bottom of the view page)


Tomes wrote:

Richard,
I also note upon looking at the setup again, that the safety chains would
attach to the same piece of metal that the hitch resides upon. If the weak
link here is the strength of the bumper material, having the chains attached
to the frame will help.

A while back in the thread, Mike painted a scenario where you might be
rear-ended and the trailer tongue shoots through the Jeep's tub. I have
actually had this happen to me. I have a pop-up camper towed by a Sienna.
While waiting to make a left turn, a van hit the back of the trailer hard.
Both the other van and the trailer were totaled. The tongue was indeed
pushed into the back of the Sienna and the force vector was straight in line
with the car's direction and also upward a bit. The upward tilt of the
hitch ball surprised me a bit, but there it was. I had to unbolt the whole
hitch and drop it to disconnect the trailer from the ball, as it was buried
up in the upper bumper. The combination of the Class 2 hitch and then the
frame of the Sienna absorbed it all, about $2500 worth of fixed damage to
the Sienna. I speculate that if I had an equivalent of this hitch design,
it would be likely that the trailer tongue would, in its upward vector,
pierce the rear of the tub and head for people in the seats.

At least safety chains attached to the frame instead of the part that is
(connected to at least) part of the failure might mitigate this. The chains
need to be of plenty of girth as well.

In other words, if the bumper is the weak point, and the chains are attached
to the metal attached to the bumper, the chains provide zero additional
help. They would only help if the trailer jumps off of the ball. I
advocate attaching them to the frame.
Tomes

"Richard J Kinch" wrote in message
. ..
Here is my design for a bumper-mounted Jeep Wrangler TJ trailer hitch:

http://www.truetex.com/jeep_trailer_hitch_bracket.htm

I know, Mike. It's just that the safety chain placement was left out of
this discussion and then I started to think about it when Bill posted about
chains. It does sound like he is married to this design; maybe better chain
placement, heavy chains **and correspondingly heavy hooks** (I forgot that
part) might mitigate things....

That is a story of yours there that made me laugh in an 'oh fine' kind of
way. I can just imagine that happening. "Will you stop that already??"
Interesting that your trailer tongue had an upward vector like mine did.
Thinking about it further, I am now betting that just about any trailer
crash will do this as the hitting vehicle will be higher than the trailer
frame, pushing down the trailer rear and thus raising the tongue spear.
Gotta have a system that can control this.

It is not just what you are towing, it is also covering what another
person's mistake can do.
Tomes

"Mike Romain" wrote in message
...
You aren't likely to convince him. He 'thinks' he is edUcated so he
knows better.

I had some short blond in a large pickup ram into my utility trailer 3
times at a red light before I got out to see what the hell she was
doing. She was so short, she couldn't see the trailer and just couldn't
understand why she couldn't get closer to me.

That one wrecked a 'legal' trailer hitch and the tongue spear also
wanted to come up over the bumper. My bumper was a 'real' one so the
tongue didn't punch through it.

Mike
86/00 CJ7 Laredo, 33x9.5 BFG Muds, 'glass nose to tail in '00
88 Cherokee 235 BFG AT's
Canadian Off Road Trips Photos: Non members can still view!
Jan/06 http://www.imagestation.com/album/pi...?id=2115147590
(More Off Road album links at bottom of the view page)


Tomes wrote:

Richard,
I also note upon looking at the setup again, that the safety chains would
attach to the same piece of metal that the hitch resides upon. If the
weak
link here is the strength of the bumper material, having the chains
attached
to the frame will help.

A while back in the thread, Mike painted a scenario where you might be
rear-ended and the trailer tongue shoots through the Jeep's tub. I have
actually had this happen to me. I have a pop-up camper towed by a
Sienna.
While waiting to make a left turn, a van hit the back of the trailer
hard.
Both the other van and the trailer were totaled. The tongue was indeed
pushed into the back of the Sienna and the force vector was straight in
line
with the car's direction and also upward a bit. The upward tilt of the
hitch ball surprised me a bit, but there it was. I had to unbolt the
whole
hitch and drop it to disconnect the trailer from the ball, as it was
buried
up in the upper bumper. The combination of the Class 2 hitch and then
the
frame of the Sienna absorbed it all, about $2500 worth of fixed damage to
the Sienna. I speculate that if I had an equivalent of this hitch
design,
it would be likely that the trailer tongue would, in its upward vector,
pierce the rear of the tub and head for people in the seats.

At least safety chains attached to the frame instead of the part that is
(connected to at least) part of the failure might mitigate this. The
chains
need to be of plenty of girth as well.

In other words, if the bumper is the weak point, and the chains are
attached
to the metal attached to the bumper, the chains provide zero additional
help. They would only help if the trailer jumps off of the ball. I
advocate attaching them to the frame.
Tomes

"Richard J Kinch" wrote in message
. ..
Here is my design for a bumper-mounted Jeep Wrangler TJ trailer hitch:

http://www.truetex.com/jeep_trailer_hitch_bracket.htm

If the OP uses safety chains he will wrap them around the bumper. I don't
know how many times I have seen this type of "design". Safety chains are
designed to cover operator error, in case the part that goes over the ball
pops off, from not being tightened enough or from a shock load it can't
stand. They are not designed to mitigate weaknesses in the actual hitch
"design".

Earle

"Tomes" wrote in message
ink.net...
I know, Mike. It's just that the safety chain placement was left out of
this discussion and then I started to think about it when Bill posted
about
chains. It does sound like he is married to this design; maybe better
chain
placement, heavy chains **and correspondingly heavy hooks** (I forgot that
part) might mitigate things....

That is a story of yours there that made me laugh in an 'oh fine' kind of
way. I can just imagine that happening. "Will you stop that already??"
Interesting that your trailer tongue had an upward vector like mine did.
Thinking about it further, I am now betting that just about any trailer
crash will do this as the hitting vehicle will be higher than the trailer
frame, pushing down the trailer rear and thus raising the tongue spear.
Gotta have a system that can control this.

It is not just what you are towing, it is also covering what another
person's mistake can do.
Tomes

"Mike Romain" wrote in message
...
You aren't likely to convince him. He 'thinks' he is edUcated so he
knows better.

I had some short blond in a large pickup ram into my utility trailer 3
times at a red light before I got out to see what the hell she was
doing. She was so short, she couldn't see the trailer and just couldn't
understand why she couldn't get closer to me.

That one wrecked a 'legal' trailer hitch and the tongue spear also
wanted to come up over the bumper. My bumper was a 'real' one so the
tongue didn't punch through it.

Mike
86/00 CJ7 Laredo, 33x9.5 BFG Muds, 'glass nose to tail in '00
88 Cherokee 235 BFG AT's
Canadian Off Road Trips Photos: Non members can still view!
Jan/06 http://www.imagestation.com/album/pi...?id=2115147590
(More Off Road album links at bottom of the view page)


Tomes wrote:

Richard,
I also note upon looking at the setup again, that the safety chains
would
attach to the same piece of metal that the hitch resides upon. If the
weak
link here is the strength of the bumper material, having the chains
attached
to the frame will help.

A while back in the thread, Mike painted a scenario where you might be
rear-ended and the trailer tongue shoots through the Jeep's tub. I
have
actually had this happen to me. I have a pop-up camper towed by a
Sienna.
While waiting to make a left turn, a van hit the back of the trailer
hard.
Both the other van and the trailer were totaled. The tongue was indeed
pushed into the back of the Sienna and the force vector was straight in
line
with the car's direction and also upward a bit. The upward tilt of the
hitch ball surprised me a bit, but there it was. I had to unbolt the
whole
hitch and drop it to disconnect the trailer from the ball, as it was
buried
up in the upper bumper. The combination of the Class 2 hitch and then
the
frame of the Sienna absorbed it all, about $2500 worth of fixed damage
to
the Sienna. I speculate that if I had an equivalent of this hitch
design,
it would be likely that the trailer tongue would, in its upward vector,
pierce the rear of the tub and head for people in the seats.

At least safety chains attached to the frame instead of the part that
is
(connected to at least) part of the failure might mitigate this. The
chains
need to be of plenty of girth as well.

In other words, if the bumper is the weak point, and the chains are
attached
to the metal attached to the bumper, the chains provide zero additional
help. They would only help if the trailer jumps off of the ball. I
advocate attaching them to the frame.
Tomes

"Richard J Kinch" wrote in message
. ..
Here is my design for a bumper-mounted Jeep Wrangler TJ trailer
hitch:

http://www.truetex.com/jeep_trailer_hitch_bracket.htm

"Richard J Kinch" wrote in message
.. .
Yeah, horrible accidents happen. The weak-hitch-equals-death analysis
makes a pleasant fictional scene, but unconvincing as to reality.

I'm a pilot, I've written embedded avionics software for commercial
aircraft, and I've written telemetry software for the Space Shuttle... I
have a MS in CS with a minor in EE... I guess that kind of classifies me as
an engineer... If there is a way that one small thing can go wrong and end
up killing someone, it definitely will sooner or later... A weak hitch could
result in a minor wreck developing into something much worse... Maybe the
initial fault of the wreck might be someone else's, but a poor design on
your part could definitely be argued as contributing to the severity of an
accident... At the very least, you might end up with damage to your vehicle
on a minor accident that you wouldn't with a more structurally sound bumper
/ hitch attachment point... Personally, I think that you should go with a 2"
receiver hitch since it gives you a lot more options for attachments other
than just a trailer hitch... Cargo carriers, bike racks, etc... Design it
right and you have a good attachment point for tow hooks so that you can get
extracted from places that you shouldn't have gone without a winch...

On Wed, 01 Feb 2006 16:39:25 GMT, "Tomes" wrote:

That is a story of yours there that made me laugh in an 'oh fine' kind of
way. I can just imagine that happening. "Will you stop that already??"
Interesting that your trailer tongue had an upward vector like mine did.
Thinking about it further, I am now betting that just about any trailer
crash will do this as the hitting vehicle will be higher than the trailer
frame, pushing down the trailer rear and thus raising the tongue spear.
Gotta have a system that can control this.

I had a similar thing happen to me. I was stopped at lights
( 4th/5th vehicle in line ) when there was a teriffic thump at my
back. Got out to find trailer drawbar was bent like an inverted V
and jammed on to towball. Tailgate and rear floor all mashed. I
was hit by a brand new Ford Focus, 84km on the clock, which was hit by
a Toyota Tarago which was hit by a Mazda ??? ( all stopped ) which was
hit by a Holden Crapadore which did not stop when he should have done.
Fortunately the only injury was bruising to a passenger in the Focus.
The Focus was probably a write off, mashed bonnet, radiator,doors
jammed etc. Not much damage to other vehicles as they all drove off.
None to my Patrol, as I have a 3500kg rated Reece tow hitch fitted to
it, which is fully used when I have a mini excavator and a small
tractor on the car trailer. Damage repair quote & cheque for my
box trailer was $486. I bought 100 x 50 box tube and a new hitch for
$150 and welded on a new ( much better , stronger ) drawbar, hit the
tailgate & floor with a BFH and, other than time spent on repair, am a
free trailer + $36 ahead as it only cost $300 when I bought it (used).

Moral - good gear saves damage.

Alan
in beautiful Golden Bay, Western Oz, South 32.25.42, East 115.45.44 GMT+8
VK6 YAB ICQ 6581610 to reply, change oz to au in address

Grumman-581 writes:

If there is a way that one small thing can go wrong and end
up killing someone, it definitely will sooner or later...

Definitely will? On my car? Possibly, but not definitely. Probability is
something often misconstrued.

I can see reasonable scenarios that a weak hitch is *beneficial*. Strong
enough for towing, but if your rig gets t-boned behind you, it breaks away
without further involving the tow vehicle.

Mike Romain proclaimed:

You aren't likely to convince him. He 'thinks' he is edUcated so he
knows better.

Yeah, sometimes one can almost appreciate why there are liability
lawyers that at least sometimes help educate such fools.

On Thu, 02 Feb 2006 19:08:50 -0800, Lon wrote:
Mike Romain proclaimed:

You aren't likely to convince him. He 'thinks' he is edUcated so he
knows better.

Yeah, sometimes one can almost appreciate why there are liability
lawyers that at least sometimes help educate such fools.

Sad thing is, if anything ever does happen with his homemade hitch, this
thread will be exhibit A.

Dave Hinz writes:

Sad thing is, if anything ever does happen with his homemade hitch, this
thread will be exhibit A.

Sadder to live in fear of liability and lawsuits. The law is on my side.

On Fri, 03 Feb 2006 15:57:31 -0600, Richard J Kinch wrote:
Dave Hinz writes:

Sad thing is, if anything ever does happen with his homemade hitch, this
thread will be exhibit A.

Sadder to live in fear of liability and lawsuits. The law is on my side.

OK, well, good luck with that, and I hope that an "I told you so"
situation never comes up. Because seems to me that "I know and I don't
give a ****" is worse, to a jury, than "I didn't know".

Good luck.

Dave Hinz writes:

OK, well, good luck with that, and I hope that an "I told you so"
situation never comes up.

Thanks. I don't expect it will. Feel free to gloat if it does. No doubt
you'll be there, subpoenaed as a plaintiff witness.

"Richard J Kinch" wrote in message
.. .
Thanks. I don't expect it will. Feel free to gloat if it does. No doubt
you'll be there, subpoenaed as a plaintiff witness.

Hell, it doesn't seem like that many years ago that you would see trucks
with bumpers made out of railroad rails or 4-6" diameter pipe... Considering
the fact that railroad rails can weigh up to 155 lbs per yd, that made for a
bit heavy bumper....
http://www.allmetalssupply.com/railroad_rail.htm

I even remember seeing one made out of a railroad tie at one time...

You are definitely going the other way in your design... Have you considered
possibly just replacing the stock bumper with something more sturdy? Even
if I wasn't towing anything, I would want to replace the factory bumper...
Bumpers should be able to withstand backing into something at a slow speed
without any damage to them... Perhaps make yourself a bumper out of 4" steel
I-beam? Here's the weights and dimensions for various sizes...
http://www.aceindustries.com/243AmStdShapes.htm

All you would need to do is create a couple of brackets to mate with the
existing factory attachment points... You could either weld a receiver hitch
adapter underneath the I-beam or just drill a few holes and mount a plate
similar to what you current have, but without the bend... I would put the
I-beam in an orientation so that it looked like an 'I' instead of a 'H'...
The mounting brackets would be welded to the inside channel of the I-beam
and as such, supported on 3 sides, making the weld fairly sturdy...

http://www.aceindustries.com/243AmStdShapes.htm

This would still be a fairly cheap solution... Not owning a TJ, I'm not
familiar with the attachment points for its bumper... It is my professional
opinion that one should design for at least as great as the weakest link in
the existing system... Basically, there's no need to put a bank vault door
on a room that has sheetrock walls...

Grumman-581 writes:

Have you considered
possibly just replacing the stock bumper with something more sturdy?

This is a long thread. Earlier, I explained why that is not a good idea.

I want a sacrificial bumper to spare the frame in a moderate collision.
The stock TJ bumpers are cheap and easily replaced. (Ridiculously easy;
I've done it. Ridiculously cheap because of all the aftermarket adding-on
yielding surplus stock bumpers on eBay.)

A bumper made of, say, 4 x 4 x 1/4 steel box beam would survive a moderate
collision, but leave you with a bent frame.