Wagon Brakes with stem casters....

I'd like to screw a stem caster into a wagon brake where the threaded rod goes. I've done this for a few lighter weight set pieces and its never worked out exactly right- but, in my defense, I hadn't had enough R&D time nor time to work out any kinks or concerns. Basically think along the lines of the 'workbench caster' that Rockler
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(and others) make that when a lever is pressed down, the caster engages, and when its lifted, the caster lifts allowing the legs or supports of whatever piece to touch the ground. I'm looking to have units that when the wagon brake/stem caster piece is engaged, the platform (or whatever) roles, and when you disengage the piece, your platform sits on its legs.
Has anyone tried this? Surely I'm not the first (if so... patent pending;):legalstuff:;)). Anyone smarter than me that has ideas as to why this wouldn't work? The downfalls I come up with on paper/in my head is that this puts a lot of shearing stress on each stem. If one stem is activated before the others, the platform/unit is lopsided until the other stems are activated, which might cause things to inadvertently roll. Deactivation may drop the unit too quickly, causing loud bangs and whatnot. Locking the wagon brake in its 'down' position versus making it easy/quiet/painless to unlock and set the unit down.

I've used the model in the picture before, but they stick out too much from the platform and are just visually distracting (as much as that shiny wagon brake or bright red or blue caster...)
I'm just looking for any suggestions, if anyone's gone down this road before.

Community and High School TD/Designer. Budget, resources and time always a top concern. Safety is in there somewhere, too...
thanks in advance!
 

DRU

Active Member
It is overall easier to brake a wheel than to remove a wheel, which is why braking a unit is more common than popping it on and off wheels. The unit stays put on the wheels instead of raising and lowering when the wheels are removed. All the issues you listed are definitely concerns.

Depending on the size of the brake, the stem might be too long and too narrow that when force is applied laterally to the brake, it bends. When that happens, you'll need to replace the brake. A larger diameter brake would help, but at increased cost. You could also add a support to the brake to brace against the lateral loads, but that would most likely be a custom made part that would add to cost and time.

Lifting also requires more force. Lifting the unit is requires more than applying a brake to stop lateral motion.

My biggest worry would be the brakes disengaging and dropping the unit off the wheels while moving. I can see it causing a chain reaction and damaging the stage or unitor people on or nearby.

I have used pneumatic pancake cylinders to both lift on casters and brake wagons. They have the same problems as wagon brakes, but they are more compact, have a shorter extention distance and thicker rods (stems) that help with the lateral force. They also cost a pretty penny. Braking, again, was the quieter and overall safer method of the two.

How big of a unit are you trying to do this with? Smaller stuff is fine, especially units where people aren't jumping on and off while in motion. If it was a bigger unit, like a wagon, I would shy away from casters on brakes. Taking time to tune the wagon brakes to brake will be less of a headache in the long run.
 

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