I found out using solely a compound lever assembly to lower & raise casters on the bottom will not work. The entire carcass will pivot on the lower lever at 1 pivot point. Meaning, the carcass will tip forward or backward, especially if running over a power cord or floor obstruction.
I didnt want to give up on my compound lever all together. As my criteria for a mobile base is:
1.) all lower and raising operation to be done as i face the machine within arms length.
2.) not wanting to hunch over, or get on knees, kick something or “thrust” carcass forward or backward to set casters.
3.) casters raise up allowing base of carcass to settle.
4.) i do not want to pull a muscle to set casters down from too much torque, hence compound lever assembly.
5.) i do not want to trip over casters that jut out at the 4 corners.
6.) i simply wants an assembly i can lightly apply pressure and move a lever 6”-12” and be happy.
this will work. i just have to figure out the details :)
my second prototype retractable casters, up 1”. mind you, this is a total rough draft run to see how it works, so no funny talk about things not being level, or placement of hinges, etc :)
and now settled on carcass base with casters retracted:
with this configuration, the compound lever is only the actuary to push the caster plate downward into place, as the casters will be attached to a 2×4 going horizontal. i foresee a good many mortises and tenons to practice on, with haunches.
The problem i am encountering, is the vertical 2×4 piece that engages the caster plate. the caster plate is roughly at a 20degree angle as the carcass sits on the ground. the vertical 2×4 engages and then wants to bow out 1/8” – 1/4” as the caster plate becomes horizontal. This “seemed” acceptable, but i still do not like it. But cant figure out how to have the 2×4 vertical piece “slide” or “rock” across the caster plate.
i put my body weight on the carcass and with just small screws holding things together, it lifted the carcass and myself up 1”. i’ll be using nuts and bolts in a final assembly.
i can not extend out the casters, as i want them as close as possible to the leg framing structure. but i think they are at a ok distance from each other when i move the carcass around. these are 3” casters. if i went 5 or 6”, they would have to come closer and that would be too close, i think.