My dilema

I did poorly when it came to math... I now regret not trying harder





I need to make a special purpose 25 foot trailer which can not appear
heavy duty.

Typically a 15,000 pound capacity trailer would have 6" C Channel
(frame) with 6" Junior I Beams (cross members) spaced 18" apart.

I am proposing that we use 4" square tubing for the entire frame
structure with cross beams spaced at 12"

Is this frame as strong as "typical" or stronger.

An additional thought: several manufacturers do what they call fold
back trailer tongues... essentially they double the beam from directly
in fron of the tires to the tongue...




--
anderson2624

"anderson2624" wrote in
message m...

My dilema

I did poorly when it came to math... I now regret not trying harder





I need to make a special purpose 25 foot trailer which can not appear
heavy duty.

Typically a 15,000 pound capacity trailer would have 6" C Channel
(frame) with 6" Junior I Beams (cross members) spaced 18" apart.

I am proposing that we use 4" square tubing for the entire frame
structure with cross beams spaced at 12"

Is this frame as strong as "typical" or stronger.

An additional thought: several manufacturers do what they call fold
back trailer tongues... essentially they double the beam from directly
in fron of the tires to the tongue...



If your metalwork can't look heavy-duty- make sure your lawers do. Not
a good thing to whip together without proper engineering. Not bashing you at
all. Honestly- Trailers are so dangerous it's scary seeing a hooptie looling
one near me in the car in traffic. I get WAY in front of him.... I'd rather
take a speeding ticket than a body bag any day.

Rob


Rob

On Mon, 4 Feb 2008 08:30:58 +0000, with neither quill nor qualm,
anderson2624 quickly
quoth:


My dilema

I did poorly when it came to math... I now regret not trying harder





I need to make a special purpose 25 foot trailer which can not appear
heavy duty.

It's against the law to cheat the DMV, boy. g Besides, any
inspector worth his salt could instantly tell that your "toy" was
built to carry a tank or two by looking at the springs and frame.

--
Our greatest glory is not in never falling, but in getting up every time we do.
-- Confucius

A 15,000 pound capacity trailer is not one to start out doing
calculations on. Too many point loads, too many flex loads, too many
fatigue loads, too many off center loads. You ask if you can use 4"
square tubing; there are lots of 25' and larger special purpose trailers
made with 4" tubing, go to any boatyard with the 22' and larger boats.
Can you make one that fits your needs from 4"? Who knows.

You posted earlier, no one here wants to touch your question. None of us
wants to stick our collective necks out for that big a project. Too many
unknowns, too much of a safety risk.



anderson2624 wrote:
My dilema

I did poorly when it came to math... I now regret not trying harder





I need to make a special purpose 25 foot trailer which can not appear
heavy duty.

Typically a 15,000 pound capacity trailer would have 6" C Channel
(frame) with 6" Junior I Beams (cross members) spaced 18" apart.

I am proposing that we use 4" square tubing for the entire frame
structure with cross beams spaced at 12"

Is this frame as strong as "typical" or stronger.

An additional thought: several manufacturers do what they call fold
back trailer tongues... essentially they double the beam from directly
in fron of the tires to the tongue...

On Feb 4, 12:30 am, anderson2624
wrote:

Is this frame as strong as "typical" or stronger.
--
anderson2624

6" C channel @13#/ft is ~20% stronger than 4" x 1/2" wall at 23#/ft.

"Rob Fraser" FraserRacing"AT"RobFraser.Net wrote


If your metalwork can't look heavy-duty- make sure your lawers do. Not
a good thing to whip together without proper engineering. Not bashing you
at all. Honestly- Trailers are so dangerous it's scary seeing a hooptie
looling one near me in the car in traffic. I get WAY in front of him....
I'd rather take a speeding ticket than a body bag any day.

Rob

I agree, except when I see some nitwit on the highway, I usually try to keep
them in front of me so I can keep an eye on them. Unless there's enough
space that I can kick it up to 85 and get far enough ahead to be safe. I
speed up to pass semis, after having three lose caps while right behind
them, or beside them. Easy to do with the turbo Cummins.

Trailers take so much flexing. Over every bend and sway and pothole and
driveway entrance. Even the good ones stress out and fail.

Anyone towing ANYTHING needs the trailer to be from two to three times the
capacity of the weight being towed. Just my opinion after seeing a lot of
them in the ditch and into abutments, guardrails, and other motorists. I
have met morons at the gas station that say their F150 will tow a 10,000#
trailer just as well as my Dodge. And they got some three story seven slide
out trailer hooked to it. IIRC, my Dodge is rated at 14,600, and 10,000 is
about all I'd want to hook it up to.

YMMV. And probably does.

Steve

Define 'stronger'?

Mechanical Magic wrote:
On Feb 4, 12:30 am, anderson2624
wrote:
Is this frame as strong as "typical" or stronger.
--
anderson2624

6" C channel @13#/ft is ~20% stronger than 4" x 1/2" wall at 23#/ft.

On 2008-02-04, Mechanical Magic wrote:
On Feb 4, 12:30 am, anderson2624
wrote:

Is this frame as strong as "typical" or stronger.

6" C channel @13#/ft is ~20% stronger than 4" x 1/2" wall at 23#/ft.

4" by 1/2" wall tubing is a little bit heavy...

i

On Feb 4, 12:30 am, anderson2624
wrote:

4" by 1/2" wall tubing is a little bit heavy...

i

i,
Yep, sure is, but still weaker.

To get a 20% increase in "strength" a 4" square bar will do it. At
53#/ft.

However the added total gross capacity of 3000# will be offset by the
added weight (2000#) resulting in a net gain of 1000#.

I didn't say it was a good idea, just answering the question.

And it would be as floppy as a wet noodle. No stiffness.

Mechanical Magic wrote:
On Feb 4, 12:30 am, anderson2624
wrote:
4" by 1/2" wall tubing is a little bit heavy...

i

i,
Yep, sure is, but still weaker.

To get a 20% increase in "strength" a 4" square bar will do it. At
53#/ft.

However the added total gross capacity of 3000# will be offset by the
added weight (2000#) resulting in a net gain of 1000#.

I didn't say it was a good idea, just answering the question.

On Feb 4, 11:55*am, "SteveB" wrote:
"Rob Fraser" FraserRacing"AT"RobFraser.Net wrote



* *If your metalwork can't look heavy-duty- make sure your lawers do.. *Not
a good thing to whip together without proper engineering. Not bashing you
at all. Honestly- Trailers are so dangerous it's scary seeing a hooptie
looling one near me in the car in traffic. I get WAY in front of him....
I'd rather take a speeding ticket than a body bag any day.

* * * * * * * *Rob

I agree, except when I see some nitwit on the highway, I usually try to keep
them in front of me so I can keep an eye on them. *Unless there's enough
space that I can kick it up to 85 and get far enough ahead to be safe. *I
speed up to pass semis, after having three lose caps while right behind
them, or beside them. *Easy to do with the turbo Cummins.

Trailers take so much flexing. *Over every bend and sway and pothole and
driveway entrance. *Even the good ones stress out and fail.

Anyone towing ANYTHING needs the trailer to be from two to three times the
capacity of the weight being towed. *Just my opinion after seeing a lot of
them in the ditch and into abutments, guardrails, and other motorists. *I
have met morons at the gas station that say their F150 will tow a 10,000#
trailer just as well as my Dodge. *And they got some three story seven slide
out trailer hooked to it. *IIRC, my Dodge is rated at 14,600, and 10,000 is
about all I'd want to hook it up to.

YMMV. *And probably does.

Steve

Excellent points Steve.

A suggestion for the group...when you see a dangerous towing situation
you first get out of the way and next you point it out to the police.
A situation like this is as dangerous to the driving public as a drunk
driver.

Many GOOD welders that I know will NOT touch a trailer simply for the
litigation risks it incurs...smart guys.

TMT

On Feb 4, 2:30*am, anderson2624
wrote:
My dilema

I did poorly when it came to math... I now regret not trying harder

I need to make a special purpose 25 foot trailer which can not appear
heavy duty.

Typically a 15,000 pound capacity trailer would have 6" C Channel
(frame) with 6" Junior I Beams (cross members) spaced 18" apart.

I am proposing that we use 4" square tubing for the entire frame
structure with cross beams spaced at 12"

Is this frame as strong as "typical" or stronger.

An additional thought: *several manufacturers do what they call fold
back trailer tongues... essentially they double the beam from directly
in fron of the tires to the tongue...

--
anderson2624


I need to make a special purpose 25 foot trailer which can not appear
heavy duty.


Care to tell us WHY the trailer cannot appear to be heavy duty? ;)

TMT

"Ignoramus31218" wrote in message
news
On 2008-02-04, Mechanical Magic wrote:
On Feb 4, 12:30 am, anderson2624
m wrote:

Is this frame as strong as "typical" or stronger.

6" C channel @13#/ft is ~20% stronger than 4" x 1/2" wall at 23#/ft.

4" by 1/2" wall tubing is a little bit heavy...

i

A "little"? That would be as heavy as 5" drill pipe. Why not just use
SOLID? Or railroad rails?

Steve ;-)

Too_Many_Tools;1210418 Wrote:
On Feb 4, 11:55 am, "SteveB" wrote:-
"Rob Fraser" FraserRacing"AT"RobFraser.Net wrote


-
If your metalwork can't look heavy-duty- make sure your lawers
do.. Not
a good thing to whip together without proper engineering. Not bashing
you
at all. Honestly- Trailers are so dangerous it's scary seeing a
hooptie
looling one near me in the car in traffic. I get WAY in front of
him....
I'd rather take a speeding ticket than a body bag any day.-
-
Rob-

I agree, except when I see some nitwit on the highway, I usually try
to keep
them in front of me so I can keep an eye on them. Unless there's
enough
space that I can kick it up to 85 and get far enough ahead to be safe.
I
speed up to pass semis, after having three lose caps while right
behind
them, or beside them. Easy to do with the turbo Cummins.

Trailers take so much flexing. Over every bend and sway and pothole
and
driveway entrance. Even the good ones stress out and fail.

Anyone towing ANYTHING needs the trailer to be from two to three times
the
capacity of the weight being towed. Just my opinion after seeing a
lot of
them in the ditch and into abutments, guardrails, and other motorists.
I
have met morons at the gas station that say their F150 will tow a
10,000#
trailer just as well as my Dodge. And they got some three story seven
slide
out trailer hooked to it. IIRC, my Dodge is rated at 14,600, and
10,000 is
about all I'd want to hook it up to.

YMMV. And probably does.

Steve-

Excellent points Steve.

A suggestion for the group...when you see a dangerous towing situation
you first get out of the way and next you point it out to the police.
A situation like this is as dangerous to the driving public as a drunk
driver.

Many GOOD welders that I know will NOT touch a trailer simply for the
litigation risks it incurs...smart guys.

TMT

It is nice to have a source for good opinions. My question was a
serious question which did not suggest that a trailer should be built
in a manner which would result is an unsafe situation for anyone. The
trailers which haul heavy equipment use 6 or 8 inch C channel. Carry
21,000 plus pounds. If anyone who responded was serious the responce
should have been this is something I do not know anything about and you
would be in good company as The National Highway Traffic Safety
Administration (sets forth trailer requirments) and the National
Institue of Standards and Technology ( metals, and composites) each a
government agency does not address or enforce the construction of a
trailer frame. Every comment I have read has some merit with the
exception of those who go off subject. Report a violator... big
problem it will do no good if no law has been broken. nitwit on the
highway...
I like that one... 2 nitwits one doing 85 mph in turbo cummings and the
other having some resolveable trailer problem... proper engineering...
I went that route, however, the answer was not 4 6 or 8 inch C channel
it was what is placed upon the C channel and the type of steel which
took me to carbon content which led to manufacturers of steel which led
nowhere. wanna buy steel fine... want us to talk about hardness or
brittleness consult an engineer.
So we have flex... stress... the best engineers do not know how to
resolve it... remember the plane in Hawaii... skin peeled right off...
today F-16's grounded flex stress... Guys I entered this site very
serious and learned this is not a place to get useful advice.
as for FraserRacing... "I'd rather take a speeding ticket than a body
bag any day.l" You speed and put me in a body bag... or some other
"innocent" in a body bag. For all of the interest I
say......thank you




--
anderson2624

"anderson2624" wrote in
message m...

Too_Many_Tools;1210418 Wrote:
On Feb 4, 11:55 am, "SteveB" wrote:-
"Rob Fraser" FraserRacing"AT"RobFraser.Net wrote


-
If your metalwork can't look heavy-duty- make sure your lawers
do.. Not
a good thing to whip together without proper engineering. Not bashing
you
at all. Honestly- Trailers are so dangerous it's scary seeing a
hooptie
looling one near me in the car in traffic. I get WAY in front of
him....
I'd rather take a speeding ticket than a body bag any day.-
-
Rob-

I agree, except when I see some nitwit on the highway, I usually try
to keep
them in front of me so I can keep an eye on them. Unless there's
enough
space that I can kick it up to 85 and get far enough ahead to be safe.
I
speed up to pass semis, after having three lose caps while right
behind
them, or beside them. Easy to do with the turbo Cummins.

Trailers take so much flexing. Over every bend and sway and pothole
and
driveway entrance. Even the good ones stress out and fail.

Anyone towing ANYTHING needs the trailer to be from two to three times
the
capacity of the weight being towed. Just my opinion after seeing a
lot of
them in the ditch and into abutments, guardrails, and other motorists.
I
have met morons at the gas station that say their F150 will tow a
10,000#
trailer just as well as my Dodge. And they got some three story seven
slide
out trailer hooked to it. IIRC, my Dodge is rated at 14,600, and
10,000 is
about all I'd want to hook it up to.

YMMV. And probably does.

Steve-

Excellent points Steve.

A suggestion for the group...when you see a dangerous towing situation
you first get out of the way and next you point it out to the police.
A situation like this is as dangerous to the driving public as a drunk
driver.

Many GOOD welders that I know will NOT touch a trailer simply for the
litigation risks it incurs...smart guys.

TMT

It is nice to have a source for good opinions. My question was a
serious question which did not suggest that a trailer should be built
in a manner which would result is an unsafe situation for anyone. The
trailers which haul heavy equipment use 6 or 8 inch C channel. Carry
21,000 plus pounds. If anyone who responded was serious the responce
should have been this is something I do not know anything about and you
would be in good company as The National Highway Traffic Safety
Administration (sets forth trailer requirments) and the National
Institue of Standards and Technology ( metals, and composites) each a
government agency does not address or enforce the construction of a
trailer frame. Every comment I have read has some merit with the
exception of those who go off subject. Report a violator... big
problem it will do no good if no law has been broken. nitwit on the
highway...
I like that one... 2 nitwits one doing 85 mph in turbo cummings and the
other having some resolveable trailer problem... proper engineering...
I went that route, however, the answer was not 4 6 or 8 inch C channel
it was what is placed upon the C channel and the type of steel which
took me to carbon content which led to manufacturers of steel which led
nowhere. wanna buy steel fine... want us to talk about hardness or
brittleness consult an engineer.
So we have flex... stress... the best engineers do not know how to
resolve it... remember the plane in Hawaii... skin peeled right off...
today F-16's grounded flex stress... Guys I entered this site very
serious and learned this is not a place to get useful advice.
as for FraserRacing... "I'd rather take a speeding ticket than a body
bag any day.l" You speed and put me in a body bag... or some other
"innocent" in a body bag. For all of the interest I
say......thank you




--
anderson2624


Mr. Anderson.

Speeding to get in FRONT of you was the point of the body bag.I don't
want a trailer coming loose at highway speed and wiping me out. I buy my
trailers by companies that are designed by bonded ENGINEERS and insured
companies. I drive like a grandpa on the road. I drive like a racer on the
track. Just contemplate buying a trailer that will absolve you of any
lawsuit and the fact you would have to live with the fact someone could die.
I am a certified welder and engineer (B.S. U of I) and I flat out refuse to
work on trailers, hitches etc. just for the reason of liability. Sure, a lot
of it is easy money but not worth it in the long run. You might find a semi
truck repair joint near you and they would be able to properly address your
concerns I bet.

Respects,

Rob Fraser

On 2008-02-07, Rob Fraser FraserRacing wrote:

Mr. Anderson.

Speeding to get in FRONT of you was the point of the body bag.I don't
want a trailer coming loose at highway speed and wiping me out. I buy my
trailers by companies that are designed by bonded ENGINEERS and insured
companies. I drive like a grandpa on the road. I drive like a racer on the
track. Just contemplate buying a trailer that will absolve you of any
lawsuit and the fact you would have to live with the fact someone could die.
I am a certified welder and engineer (B.S. U of I) and I flat out refuse to
work on trailers, hitches etc. just for the reason of liability. Sure, a lot
of it is easy money but not worth it in the long run. You might find a semi
truck repair joint near you and they would be able to properly address your
concerns I bet.


Rob, this was interesting to read. Since you obviously know a lot
about welding, and also have seen my trailer, I am curious about your
opinion. Would you think that my trailer will hold up to normal use
under the rated limit of 5k lbs gross? Any particular weaknesses that
you noticed? I do realize that we were busy with the Bridgeport then.

i

railroad rails are not considered good for structural purposes like this.
Every time a train wheel rolls over them, they get strain hardened making
the rail very brittle.

--
don paolino
"SteveB" wrote in message
...

"Ignoramus31218" wrote in message
news
On 2008-02-04, Mechanical Magic wrote:
On Feb 4, 12:30 am, anderson2624
m wrote:

Is this frame as strong as "typical" or stronger.

6" C channel @13#/ft is ~20% stronger than 4" x 1/2" wall at 23#/ft.

4" by 1/2" wall tubing is a little bit heavy...

i

A "little"? That would be as heavy as 5" drill pipe. Why not just use
SOLID? Or railroad rails?

Steve ;-)