Trailer Axel / Physics Puzzler
 

So the axels that we have are torsion axels (no springs). They will just
attach
directly to the underside of our trailer. The thing is, it's not just a
straight
across axel. Well, the axel goes straight across, but coming from the
center of the axel is a 6" arm that goes back to the spindle. In other
words,
the tires are off-set 6" behind where the axel is.

For a picture go to this web sire (really an Adobe PDF document)
and see page 5 (the 2,300 lb to 3,500 lb Torflex axel).
http://www.redneck-trailer.com/pdf/A/810torflex.pdf


PUZZLER: Does the axel "balance" the weight over the
axel or over the wheels? .

Put another way: Say we had a rectangular frame 20 feel long and
it was perfectly balanced at the 10 point. (No boat or anything on
it yet.) So a straight across axel put at the 10' point, it'd basically
balance. But with our axels, where the wheels are off-set 6"....do
we put the AXEL at that 10' point or do we have the
WHEELS at that 10' point.

Our current thinking is that it's the wheels. It's pretty hard to test
because of the weights involved and we have to weld the axels on
(not bolt 'em) so we'ld like to get it right the first time.

Gary

Trailer Axel / Physics Puzzler
 

QLW wrote:
I've never built a trailer using torsion axels but I like the concept. I
wonder how to design a 2 axle system to achieve equalization? I'm thinking
a rotating sub-frame would be required. I have built several single axle
trailers with trailing arms and coil over springs that worked well but were
a lot of work to build.
IMHO, the balance point will be over the CL of the wheels.

"Gary Warner" wrote in message
...

So the axels that we have are torsion axels (no springs). They will just
attach
directly to the underside of our trailer. The thing is, it's not just a
straight
across axel. Well, the axel goes straight across, but coming from the
center of the axel is a 6" arm that goes back to the spindle. In other
words,
the tires are off-set 6" behind where the axel is.

For a picture go to this web sire (really an Adobe PDF document)
and see page 5 (the 2,300 lb to 3,500 lb Torflex axel).
http://www.redneck-trailer.com/pdf/A/810torflex.pdf


PUZZLER: Does the axel "balance" the weight over the
axel or over the wheels? .

Put another way: Say we had a rectangular frame 20 feel long and
it was perfectly balanced at the 10 point. (No boat or anything on
it yet.) So a straight across axel put at the 10' point, it'd basically
balance. But with our axels, where the wheels are off-set 6"....do
we put the AXEL at that 10' point or do we have the
WHEELS at that 10' point.

Our current thinking is that it's the wheels. It's pretty hard to test
because of the weights involved and we have to weld the axels on
(not bolt 'em) so we'ld like to get it right the first time.

Gary





Yes you are correct, the wheels are the pivot point, not the rubberised
section & cross beam (it's sorta like the spring hanger, if you had
them:-)) It wouldn't matter if the torsion fittings attached just behind
the coupling or just ahead of the extreme rear, the trailer & it's load
still pivot around the wheels.

K

Trailer Axel / Physics Puzzler
 

I've never built a trailer using torsion axels but I like the concept. I
wonder how to design a 2 axle system to achieve equalization? I'm thinking
a rotating sub-frame would be required. I have built several single axle
trailers with trailing arms and coil over springs that worked well but were
a lot of work to build.
IMHO, the balance point will be over the CL of the wheels.

"Gary Warner" wrote in message
...

So the axels that we have are torsion axels (no springs). They will just
attach
directly to the underside of our trailer. The thing is, it's not just a
straight
across axel. Well, the axel goes straight across, but coming from the
center of the axel is a 6" arm that goes back to the spindle. In other
words,
the tires are off-set 6" behind where the axel is.

For a picture go to this web sire (really an Adobe PDF document)
and see page 5 (the 2,300 lb to 3,500 lb Torflex axel).
http://www.redneck-trailer.com/pdf/A/810torflex.pdf


PUZZLER: Does the axel "balance" the weight over the
axel or over the wheels? .

Put another way: Say we had a rectangular frame 20 feel long and
it was perfectly balanced at the 10 point. (No boat or anything on
it yet.) So a straight across axel put at the 10' point, it'd basically
balance. But with our axels, where the wheels are off-set 6"....do
we put the AXEL at that 10' point or do we have the
WHEELS at that 10' point.

Our current thinking is that it's the wheels. It's pretty hard to test
because of the weights involved and we have to weld the axels on
(not bolt 'em) so we'ld like to get it right the first time.

Gary

Trailer Axel / Physics Puzzler
 

QLW wrote:
I've never built a trailer using torsion axels but I like the concept. I
wonder how to design a 2 axle system to achieve equalization? I'm thinking
a rotating sub-frame would be required. I have built several single axle
trailers with trailing arms and coil over springs that worked well but were
a lot of work to build.
IMHO, the balance point will be over the CL of the wheels.

"Gary Warner" wrote in message
...

So the axels that we have are torsion axels (no springs). They will just
attach
directly to the underside of our trailer. The thing is, it's not just a
straight
across axel. Well, the axel goes straight across, but coming from the
center of the axel is a 6" arm that goes back to the spindle. In other
words,
the tires are off-set 6" behind where the axel is.

For a picture go to this web sire (really an Adobe PDF document)
and see page 5 (the 2,300 lb to 3,500 lb Torflex axel).
http://www.redneck-trailer.com/pdf/A/810torflex.pdf


PUZZLER: Does the axel "balance" the weight over the
axel or over the wheels? .

Put another way: Say we had a rectangular frame 20 feel long and
it was perfectly balanced at the 10 point. (No boat or anything on
it yet.) So a straight across axel put at the 10' point, it'd basically
balance. But with our axels, where the wheels are off-set 6"....do
we put the AXEL at that 10' point or do we have the
WHEELS at that 10' point.

Our current thinking is that it's the wheels. It's pretty hard to test
because of the weights involved and we have to weld the axels on
(not bolt 'em) so we'ld like to get it right the first time.

Gary

Out of curiosity, how does one place the axle? Is it at the centerpoint?
I think you'd want it a bit forward of the centerline. I built a box
trailer some years ago, and was advised to have the axle forward of
center under the box. I knew why at the time, but I've since forgotten.



--
Email sent to is never read.

Trailer Axel / Physics Puzzler
 

On Mon, 26 Jan 2004 01:23:21 -0500, "Gary Warner"
wrote:


So the axels that we have are torsion axels (no springs). They will just
attach
directly to the underside of our trailer. The thing is, it's not just a
straight
across axel. Well, the axel goes straight across, but coming from the
center of the axel is a 6" arm that goes back to the spindle. In other
words,
the tires are off-set 6" behind where the axel is.

For a picture go to this web sire (really an Adobe PDF document)
and see page 5 (the 2,300 lb to 3,500 lb Torflex axel).
http://www.redneck-trailer.com/pdf/A/810torflex.pdf


PUZZLER: Does the axel "balance" the weight over the
axel or over the wheels? .

Put another way: Say we had a rectangular frame 20 feel long and
it was perfectly balanced at the 10 point. (No boat or anything on
it yet.) So a straight across axel put at the 10' point, it'd basically
balance. But with our axels, where the wheels are off-set 6"....do
we put the AXEL at that 10' point or do we have the
WHEELS at that 10' point.

Our current thinking is that it's the wheels. It's pretty hard to test
because of the weights involved and we have to weld the axels on
(not bolt 'em) so we'ld like to get it right the first time.

Looking at the specs and not knowing the exact weights involved
(boat/motor and trailer frame), my opinion would be a tad forward of
the wheel's centerline, but with reservations. I have a suspicion
that if you did some basic experimenting, you would find the weight
transfer somewhere between the wheel and axel - more likely towards
the axel than the wheel, but again, not knowing the weights, I can't
say for sure.

Later,

Tom
S. Woodstock, CT
----------
The years will bring their Anodyne,
But I shall never quite forget,
The fish that I had counted mine
And lost before they reached the net.

Colin Ellis, "The Devot Angler" quoted
in A. R. Macdougall, Jr's "The Trout
Fisherman's Bedside Book" (1963)

Trailer Axel / Physics Puzzler
 

"QLW" wrote in message ...
I've never built a trailer using torsion axels but I like the concept. I
wonder how to design a 2 axle system to achieve equalization? I'm thinking
a rotating sub-frame would be required. I have built several single axle
trailers with trailing arms and coil over springs that worked well but were
a lot of work to build.
IMHO, the balance point will be over the CL of the wheels.

"Gary Warner" wrote in message
...

So the axels that we have are torsion axels (no springs). They will just
attach
directly to the underside of our trailer. The thing is, it's not just a
straight
across axel. Well, the axel goes straight across, but coming from the
center of the axel is a 6" arm that goes back to the spindle. In other
words,
the tires are off-set 6" behind where the axel is.

For a picture go to this web sire (really an Adobe PDF document)
and see page 5 (the 2,300 lb to 3,500 lb Torflex axel).
http://www.redneck-trailer.com/pdf/A/810torflex.pdf


PUZZLER: Does the axel "balance" the weight over the
axel or over the wheels? .

Put another way: Say we had a rectangular frame 20 feel long and
it was perfectly balanced at the 10 point. (No boat or anything on
it yet.) So a straight across axel put at the 10' point, it'd basically
balance. But with our axels, where the wheels are off-set 6"....do
we put the AXEL at that 10' point or do we have the
WHEELS at that 10' point.

Our current thinking is that it's the wheels. It's pretty hard to test
because of the weights involved and we have to weld the axels on
(not bolt 'em) so we'ld like to get it right the first time.

Gary


Your current thinking is correct, if all things equal, AND if you
didn't consider the torsion of the spring. Again, if you put the wheel
at the center of gravity of the boat, it will be balanced. Trouble is,
when this is done, will the boat's C.G. be at the C.G. of the trailer?
See, you could load the boat on the trailer, and the CG of the boat
could be far enough behind that the tongue has a negative load.

Trailer Axel / Physics Puzzler
 

"Gary Warner" wrote in message ...
So the axels that we have are torsion axels (no springs). They will just
attach
directly to the underside of our trailer. The thing is, it's not just a
straight
across axel. Well, the axel goes straight across, but coming from the
center of the axel is a 6" arm that goes back to the spindle. In other
words,
the tires are off-set 6" behind where the axel is.

For a picture go to this web sire (really an Adobe PDF document)
and see page 5 (the 2,300 lb to 3,500 lb Torflex axel).
http://www.redneck-trailer.com/pdf/A/810torflex.pdf


PUZZLER: Does the axel "balance" the weight over the
axel or over the wheels? .

Put another way: Say we had a rectangular frame 20 feel long and
it was perfectly balanced at the 10 point. (No boat or anything on
it yet.) So a straight across axel put at the 10' point, it'd basically
balance. But with our axels, where the wheels are off-set 6"....do
we put the AXEL at that 10' point or do we have the
WHEELS at that 10' point.

Our current thinking is that it's the wheels. It's pretty hard to test
because of the weights involved and we have to weld the axels on
(not bolt 'em) so we'ld like to get it right the first time.

Gary

Seems to be a pretty good explanition and info on page two of the PDF
you link to unless I am reading the thing wrong. Otherwise, I think
the best bet would be to call them and ask them to clarify for you.
Scotty

Trailer Axel / Physics Puzzler
 

Harry Krause wrote in message ...
QLW wrote:
I've never built a trailer using torsion axels but I like the concept. I
wonder how to design a 2 axle system to achieve equalization? I'm thinking
a rotating sub-frame would be required. I have built several single axle
trailers with trailing arms and coil over springs that worked well but were
a lot of work to build.
IMHO, the balance point will be over the CL of the wheels.

"Gary Warner" wrote in message
...

So the axels that we have are torsion axels (no springs). They will just
attach
directly to the underside of our trailer. The thing is, it's not just a
straight
across axel. Well, the axel goes straight across, but coming from the
center of the axel is a 6" arm that goes back to the spindle. In other
words,
the tires are off-set 6" behind where the axel is.

For a picture go to this web sire (really an Adobe PDF document)
and see page 5 (the 2,300 lb to 3,500 lb Torflex axel).
http://www.redneck-trailer.com/pdf/A/810torflex.pdf


PUZZLER: Does the axel "balance" the weight over the
axel or over the wheels? .

Put another way: Say we had a rectangular frame 20 feel long and
it was perfectly balanced at the 10 point. (No boat or anything on
it yet.) So a straight across axel put at the 10' point, it'd basically
balance. But with our axels, where the wheels are off-set 6"....do
we put the AXEL at that 10' point or do we have the
WHEELS at that 10' point.

Our current thinking is that it's the wheels. It's pretty hard to test
because of the weights involved and we have to weld the axels on
(not bolt 'em) so we'ld like to get it right the first time.

Gary

Out of curiosity, how does one place the axle? Is it at the centerpoint?
I think you'd want it a bit forward of the centerline. I built a box
trailer some years ago, and was advised to have the axle forward of
center under the box. I knew why at the time, but I've since forgotten.

If a standard type of axle, and if placed at the c.g. of the trailer,
it would be in equalibrium, ie: balanced. If placed aft of the
centerline, it would have tongue weight, if forward, when you unhooked
the tongue, it would rise. Now, if using the torsion springed axle,
where there is a lever arm all of this goes out the window, because
the spring torsion, depending on which direction the wheel arm is
pointing, will either try to raise the tongue, or lower the tongue.

Trailer Axel / Physics Puzzler
 

Thanks all for the replys.

I will call the company and ask them too, but I always like
the comments and thought processes I get here.

Trailer Axel / Physics Puzzler
 

"Harry Krause" wrote:

Out of curiosity, how does one place the axle? Is it at the centerpoint?
I think you'd want it a bit forward of the centerline. I built a box
trailer some years ago, and was advised to have the axle forward of
center under the box. I knew why at the time, but I've since forgotten.


I'm not an expert (obviously) but our thinking is: We experimented
with the trailer WITH the boat on it to find a point that is just BACK
of the true center of gravity. A single axel placed right AT the center
of gravity would give essentiall no tongue weight. Moving the single
axel back just a little gives some tongue weight.

In our case we are putting tandem axels. So one axel will go forward
of the point we found and the other back of that point by the same
distance.