Technically speaking, you do not have true Ackerman steering unless the
outside wheel does not turn to as sharp an angle as the inside. This is
the way to make the two steering casters move to the different radius
turns.

As long as the distance from the tongue pivot pin to the drag link is
the same as the distance from the caster pivot to it's drag link hole
AND the drag link is straight to start, you will have decent turning but
not exact turning.

there are a couple ways to get the correct geometry: first is to make
the pivot points for the caster draglinks offset from the line of travel
to the INSIDE. The offset angle and length are both critical. You can
also move the drag link center point forward(?)to get close but not exact.

dave wrote:
I hate swivel casters on one end of a dolly when the load is real
*heavy*. they're ok when the load is light but when the dolly is HEAVY,
it's OK going straight in one direction, but IMPOSSIBLE to get turned
around unless you either jack up one end of the cart and turn the
steering casters by hand OR you "have a spare mile or so" of room to
maneuver. and space availability in my garage is 'far less than optimal'

so I want to convert some 'normal' swivel casters (have tons of 'em) to
'ackerman steer' casters. I need two stout acker-dollies: one to hold my
dialarc (with other stuff piled on top of it) and another dolly for my
500 lb table saw.

-----------------------------
anybody here ever tried this?
-----------------------------

I'm pretty sure it can be done by welding 'ackerman ears' to the tops of
the forks of 'normal' swivel casters. a little bizarre, perhaps, but
workable. put it this way: the geometry seems to work in the mockup I
made (and illustrated) he

http://bubba.hostrator.com/ackerman_...rs_conversion/

comments invited :-)

thanks,

toolie dave

ps-I'm familiar with the 'running gear' miller sells for this welder,
with its' a
href="http://freemanracing.com/home/components/com_virtuemart/shop_image/product/ca2435dd117737d6bee9ae138f447dbf.jpg""kid's
wagon" type steering/a, and I think this ackerman-mod idea is better.
I realize having swivel casters with "no trail" would be better, but, I
might cut mine and reweld them "straight-forked", OR just "leave the
forks like they are now", but with their newly-attached ears. well, let
me know :-)

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