A
turntable project, one of my favorite subjects. The reason I came to this site two years ago was I was seaking advice on building a
turntable for a production of Les Mis. I had never built one before. The best advice I can give is to do your research.
Talk to people who have built turntables, revolving stages or revolves as they are known. Look into many designs and plans and decide which best fits your budget, time frame and resources.
I found a few really good sources for design information. Two books: Technical Design Solutions for
Theatre, Volume 1 & 2 - by Sammler & Harvey - Focal Press. (available at Amazon.com) They have several articles on
turntable construction and drive systems. I also found a great paper written by Dan Ports, a Music and
Theatre Arts student at MIT on the design of a drive
system:
http://ocw.mit.edu/courses/music-an...effects-spring-2004/assignments/drkp_proj.pdf
I used this paper as the basis of our drive
system. The nice thing about a chain drive
system like this is the rotation is not limited. We did not use his plan for the plywood
turntable construction, it was for an 20' diameter
turntable which is not easily adapted to the 24' size we needed. However, this may well work for you. Ours was something of a hybrid design. As far as cost, we built a 24'
turntable with a motorized chain drive mechanism and the surrounding
deck for ~$5000. I bought the 2HP motor on a close out sale from Graingers for about half the cost of a new one. The speed reducer was purchased on eBay for $150 which is 1/4 the cost of a new one. The 68 fixed casters we used were $1100 new. The lumber was purchased locally through a commercial yard.
A few hints: Use the best grade of plywood you can afford. Plywood used for roof sheathing for instance is relatively inexpensive but often has a rough surface that will generate noise while moving over the casters. This type of plywood also
bows easily when the humidity & temperature changes. "A" grade plywood is often 2X (or more) the cost of sheathing but it is very smooth and very stable. We used 4" ball bearing casters with
polyurethane wheels. This is a good balance between load capacity and the soft wheel surface to minimize noise. We mounted the casters on plywood strips on the
stage floor with the wheels up. This allowed us to
level out the casters with shims to compensate for the uneven floor. Our musical director was understandably concerned about noise when the
turntable was moving during the performance. He was very happy the
turntable could bearly be heard in the pit while moving.
The load capacity must also be a prime concideration. I learned (the hard way) many years ago when the director says there will be 20 actors on the
turntable you had better plan for twice that many. We used three overlaping layers of 3/4" plywood to construct the
turntable. I am very glad we did when we had the entire 50 + chorus on the
turntable for the epilogue.
The
turntable we built moves at 1rpm which may sound slow but when you consider the actors have to walk on and off the moving
turntable during the performance it still takes some getting used to. That speed worked well for us for Les Mis. We set up the scenes behind the action
downstage then rotated the actors and
props into position during the scene change.
If you have a limited budget (£1000) you may concider renting a
turntable. There is a company in the UK called (oddly enough) The Revolving
Stage Company that rents turntables for shows and concerts you may want to look into:
The Revolving Stage Company
We were very fortunate to have an adequate budget and best of all we have a great group of adult volunteers that have been doing set construction for many years. Many have stayed on years after their children have graduated.
I wish you luck with this project, it will be a challenge but well worth it. Please keep us informed on your progress.