On 5/20/2014 9:33 AM, Gramps' shop wrote:
I need to load a riding mower onto the bed of my truck. Considering using 2x12s for the ramps, braced at the midpoint. Can they handle this?

I have the same situation with an atv. I have a pair of atv ramps made
out of aluminum that I bought for another truck, then got a Dodge 2500
which has a substantially higher bed height. The ramps work, but I am
about at a 45 when going up them. They have transverse rods, so the
tires don't slip. Your two by's won't have anything to prevent side slip.

When loading and unloading, I look for a berm, or a hill, or somewhere I
can put the wheels in a recess to reduce the incline. For a riding
mower, I don't know what your torque or gear reduction is, but they are
made for going in a straight line, and not for climbing slopes. You may
have a problem getting it to climb a steep ramp.

If it was me, this is how I would do it: A lot is being said about this
and that, and I think some of the most important parts are being
ignored. I would put a side guide on each side if each board, like a
piece of flat bar that would keep the wheel from going off. I would put
some expanded metal on top of the board for traction. Or that non slip
stuff that comes in 4" wide pieces. Use contact cement to put it on. I
would put some type of hook type device, or chains to hold the tops of
the boards steady on whatever they will go on, either tailgate or bed.
A piece of reinforcement angle under the two by wouldn't hurt.

You are not going to find out how this will all work until you use them.
You will have wet tires, grass, water, and smooth wood. You will have
tires that have smooth surfaces, meant to treat grass kindly, and not to
climb. If you have any shift in the boards, or one of the wheels slides
to the side, you are going to be in a hairy spot with the mower half way
up the ramp. Getting off is going to be iffy, whether or not the
machine will stay on the ramps or crash to the ground. Mowers have
decks and all sorts things sticking out, not like atv's that have a lot
of clearance on them, so there are lots of things to grab hold of while
you are going up and down the ramps. You will have to do some tests to
make sure when you reach the breakover point that the deck and all will
not scrape on the tailgate edge.

You are loading a heavy machine on an incline. The traction is a
question. The stability is questionable.

With all said, the most important thing you can do in your loading and
unloading process is to look for a spot that will give you the least
angle for the boards. Make them as long as the bed of the truck,
utilizing length to reduce angle.

I have loaded atvs hundreds of times. Sometimes with factory ramps, and
sometimes with rocks we rounded up. We have had about a dozen times
when someone gets antsy, and drives them off the trailer with no ramps,
about an 18" drop, and they survived with all teeth and bones intact.
ATVs are meant to climb. We (I) have not had one come off a ramp yet,
but we use special aluminum ramps made for that or factory fold downs.
Have you considered buying a pair of industrially made ramps? About
$300 new, a lot less used.

If you will be using this regularly at a spot that you know is stable,
and you know how it will act, you could probably just get by with a
couple of two bys. If you are going to use it under a different set of
circumstances every time, you will need a good solid set of ramps that
will cover most any situation.

Be safe. If you get half way up that ramp that ramp, and things go
squiggly, you are going to be in a VERY dangerous spot. VERY. What you
are proposing is simple in principle, but then reality takes over, and
**** happens.

Let us know what you do and how you do it, so we can apply the
knowledge. And laugh at the funny stories, or maybe commiserate until
the casts come off.

Steve