Wagon casters

bobgaggle

Well-Known Member
I just saw the most recent tour of My Fair Lady at the Kennedy Center in DC. I got to go on a backstage tour of the show and noticed the wagons they use to move scenes on and off. Naturally they used a tracked deck with a cable system to move the wagons, but I couldn't figure out what kind of wheels they were using. Of course we weren't supposed to touch anything, but as the group moved forward I couldn't resist. I lagged behind and gave the thing a shove. Needless to say it sailed like a ghost 7 or 8 feet across the stage before the cable jerked it to a stop (and I probably fouled it up in the motor too :(

But I have no idea how they got that thing to be so silent and so low to the ground (it was 2" max off the deck) Anyone know how to do this?

Air cushion?
Uber soft rubber wheels?
Mag Lev?
The Force?
 
Hmmm Good question. Don't think it would have been air casters, as they require a constant supply of air when lifting, and you certainly don't leave big wagons lifted when tours are comming through. Were the wagons tracked with a rail on the stage? In that case I say it was probably dual or right angle roller ball casters. Or maybe, since it's a big show they have the money to buy really good ball bearing casters, unlike us schmucks in the Non-Profit world who get by on rollerskate wheels and 1/4" bolts.
:mrgreen:
 
It's been 25 years since I've spec'd casters, are Darnells still the Rolls Royce of the industry?
 
Total height (not clearance) of the wagon was 2". I've been googling like mad and I can't find anything. The wagons just had two knives in the track (on in front and one in back) to which the cable was attached.

Doing a bit o' research on UHMWPE...is it really low friction?
 
Last edited:
It's been 25 years since I've spec'd casters, are Darnells still the Rolls Royce of the industry?

Yes, they are. Dunno if the name has changed since you spec'd though, the full name is now Darnell-Rose but I just call the casters Darnells.

Ooohh...2" total thickness...now I really want to know what the deal is here!
 
so what defines low weight? would it glide with a desk on the wagon? a few people? only a folding chair?
 
If you don't have a copy of Technical Design Solutions for Theatre buy volume one and look pages 210-214 because there is a very well written write up of several different plastics that can be used as guides.

Using the Formula F=UN where F is the amount of force to start movement, U is the coefficient of static friction and N is the weight of the object being tested

UHMWPE has a U value of .17

you can do the rest of the math to figure out how much weight you can apply and still only need to give it a good shove.
 
I just got it for Christmas. It's Excellent so far.
 
The big issue with UHMW or UHMD PE< Ultra High Molecular Weight or Ultra High Molecular Density, Poly-Ethyline> is Expense! The stuff should be should as a High value commodity on the stock market, or maybe used as a currency base like gold. It is very cool stuff, and fun to work with as you can route, cut, Lathe, and machine it just like Wood and Metal combined.
 
It's funny you mentioned that book!I just ordered both volumes and rigging book, they should be here in a week:)
 
nah i've seen it in canada...it's like polo but with blades attatched to the hooves
 
you all have an uncanny knack for getting off topic...isnt' there a area for that somewhere on this site?!!?!?!?! ;)
 
Sorry Aaron, but I had to say this, I saw a license plate today that sayed
"horse hcky"
 

Users who are viewing this thread

Back