Frame help

[angib]

Then there is also the issue of "galvanic action" between the dissimilar metals to deal with.

That doesn't seem to be a problem, in reality, only in theory.

If you wanted to drive your trailer up and down a salt water beach, then worrying about galvanic action might be sensible -though even then, just plain rusting of the steel components would probably be a bigger problem than galvanic corrosion.

[terryjones1]

Here are a couple frame ideas I came up with earlier on for lowering
the floor to gain headroom. Lowering the floor fore and aft of
the wheels wouldn't really present that much of a clearance
problem in my view.

[Click on pics for a larger view.]



and



Cheers,
Norm/mezmo

I do not see how raising the front height of the frame plus raising the back part of the frame (in back of axle) gives more headroom.
The headroom would be the same as if you just had a straight & level frame.
Headroom will depend upon how high you make the trailer.
If the idea is to park the trailer in the garage, then raising the frame, as you propose, does not help.
If you, however, have the drop frame start the drop in front of the axle (insted of in back of the axle), you can then have the inside clearance needed, depending on the amount of the frame drop, to truly add head room.

Look at the example of what I am talking about in Doug Hodder's TTT build
viewtopic.php?f=50&t=32236&hilit=sierra+nomad
Look at my build for another example.

[mezmo]

Hi Terry,

The point of my thoughts on the frames I drew, is to make the
'drop' floor go side to side and be of a larger area. I personally find
the step-over into the usual step-down well of a drop floor annoying -
even though the drop floor itself is beneficial.

I think you must be interpreting the drawings differently than what they
are meant to show. The higher levels of the frames in my drawings are
more or less where a usual straight frame level would be - that of course
is variable per build/builder. The lower levels of the frame, as drawn, are under
the usual straight frame level - thus stepping it down in effect.

I was thinking of more of about a '4in x2in' frame size member cross-
section size, better yet, using a "C" channel frame of that nominal
dimension, that you could inset the frame cross-members and floor
insulation within and then apply the floor plywood on top of that, or
if you choose, use a 2in-3in tall cross-member size, and all that can go within
the 4in "C" channel cross-section dimension and you can then gain a couple
inches of headroom that way. [I'm also envisioning using a smooth enclosed
underbelly and having nothing in the floor itself but structure and insulation.]
Frame member dimensions/weight are a personal decision in my view here. I
went with the '4in x 2in cross-section' size here as it'd be stiffer than a square
tube. I like the "C" channel as it is more versitle I think, plus you can rust proof it better
than a tube profile. Anyway, with one given length of 4in "C" channel you can
make two appropriately angled cuts, per the drop floor length and front and
rear upper lengths desired, then overlap them the appropriate length [above/under]
and weld them together. If gussets are required, add them. It's benefits are: Fewer
cuts and easier and longer welds than using mitre cuts and small pieces etc..
It's just a different approach to doing it.

If the ground clearance from the ground to the the bottom surface of
the enclosed smooth underbelly is say, 8in, and the total floor thickness is 4in,
and the interior headroom is 72in, and the roof thickness is 2in, then the total
trailer height is 86in, or 7ft 2in - probably about a foot shorter than the average.
I was not trying to specifically make a drop/stepped frame to make a trailer be
under the nominal 84in 'standard' garage door opening height, just a total lower
trailer height. Tweaking any of the example dimensions in this paragraph would
easily achieve under 84in if that was what was desired/needed. In general, a lower
trailer height helps decrease frontal drag, as more of the trailer is in the tow vehicle's
cross-sectional area, which has already 'punched' through the air.

What my drawings show is pretty much a variation on what you did for your build,
with just with a larger floor area for the dropped floor portion and using a larger
dimension cross-section steel to make the frame. My drawings also assume an
integral or under surface mounted torsion axle as a cross member and using an "up"
angle on the suspension arm holding the wheel spindle. Your pics seem to show you used
a "down" angle on that. All of that just depends on what one's final desired dimensions
for all of that are and the design. [I just went back through your build journal fast,
looking at the pics of what you did.]

So I hope I cleared this up for you. Feel free to ask any questions if you have them.

I really like your trailer and the thoroughness with which you approached the build.
You achieved outstanding results. It's a great rolling achievement, and an inspiration
to all of us fellow home builders.

Cheers,
Norm/mezmo

[Bogo]

Then there is also the issue of "galvanic action" between the dissimilar metals to deal with.

That doesn't seem to be a problem, in reality, only in theory.

If you wanted to drive your trailer up and down a salt water beach, then worrying about galvanic action might be sensible -though even then, just plain rusting of the steel components would probably be a bigger problem than galvanic corrosion.

Some of us live in places where they salt the roads...