Questions about platforms

[motek]

Hello everyone,

After having a lot of questions answered from other posts, I've recently joined with a need for some answers about my platform situation:

1) I built some platforms using some plywood top pieces and 2x4's for frames that were a little warped. Due to some scheduling problems, the lumber was stored outside for 2 days and it snowed. I brought it all inside, stacked it up flat and weighed it all down for a week; When I went to build them they seemed to be mostly straight. After building the frames and putting the tops on, some platforms do not sit exactly flat on the floor. They are for a traveling play and we are putting the platforms together to make decks.

Are these platforms a total loss? Will they be flat enough to walk on once I leg them up? Any advice for my situation?


2) I will be using two carriage bolts per 2x4 leg on these 2x4 framed platforms. The legs will be 15 inches and 31 inches. What is the best way to put legs on to ensure the leg is perpendicular to the top piece? Flip over the platform, clamp, then drill? Which directions should I clamp? Any tips?


Thanks everyone,

Motek

 

[Footer]

For a touring type of show, your not going to be happy with carriage bolts. Over time (3 or 4 in/outs) they are going to loosen up a pretty good amount. I would suggest with either building a small studwall that the platform will sit on (it can loose pin hinge on/off) or buying something like this TheatricalHardware.com Leg-a-Matic.

For the 15" leg, you should be fine to just attach the leg. For the 31" leg, you are going to have to brace that leg. It can be as simple as a 1x4 at a 45 on both sides of the leg. Otherwise, that platform is going to wobble. If you use the legomatic hardware that might prevent having to do a brace.

As far as the warping goes.... I would say leg up the platforms and shim the legs to make it level. Odds are the floors you are performing on won't be perfect either. Now, if you have to shim more then 3/4" you might want to consider a rebuild. It really just depends on how bad the warp is.

 

[motek]

Hi Footer,

Thanks for replying!

Re: warping - I'll leg em up and see how it goes, hopefully I won't have to shim too much. I may attach shims to the bottom of the legs if I need to.

About the leg-o-matic hardware - we can't afford those - I'm gonna make the holes 3/8" so bolts will be real snug, I hope they wouldn't be that loose after 4 load-outs.

Small studwall - what is that? Like a long rectangular box?

More info: - there are 10 platforms total, six platforms of the 18"inch height (typo on last post) and four of the 3' height. Two decks of three platforms each (the lower level) and two decks of two platforms each (the higher level)

I also meant how to secure the legs while I drill the bolt holes, not which type of legs to use - what's the best way to have the legs held still while drilling holes for the bolts?

Thank you again for the advice.

- Motek

 

[motek]

Also, I will be doing side bracing for the longer legs as outlined in the other articles about platform on the site.

 

[Footer]

A good old C-clamp is what I usually use to hold the legs in place. You might want to make a jig piece and use that to drill all your holes that way any leg can fit any platform.

A studwall is a what is used to build walls in many homes and buildings. It contains vertical 2x4's with a 2x4 top and bottom piece.

It is quickly being adopted in the theatre world to use as a structural support for platforming systems. It is a very efficient way to quickly lay down a deck and is extremely strong. They can quickly be attached to a platform and require less bracing, if any, then a traditional leg.

 

[motek]

Wow, the studwall solution seems really good and fast. Would you need to modify the top plate, or does the top plate just rest along the crosspieces of the platform frame? Does the loose-pin hinge go on the top plate to the frame?

Also, would you replace all legs with two studwalls per platform?

Thanks so much for the help, I have to build these on Wednesday so I'm trying to figure out what legging system to use, so I can plan ahead as much as I can...

 

[kicknargel]

I concur that studwalls are the way to go. The problem with carriage bolts is not so much the tightness of the hole, but that after a few uses the square part of the bolt head won't have anything to grip and the bolt will spin in place. Your strike will turn into what I call "carriage bolt hell."

 

[motek]

Wow, I'm really glad I joined and started a thread. I also really wish I had consulted controlbooth sooner, could have done it correctly from the start.
I'll have to return all those carriage bolts and wingnuts I just bought.

Anyways, so I think I will be doing the studwall system now... I guess you don't even need a frame for the platforms if you use studwalls. The frame seems a little redundant now.

Also from this article
http://www.hstech.org/howto/carpentr/plats/mpplats6.htm
It says studwalls can be better for large decks.

So, if I already have the platforms built with 2x4 frames, I've gotta figure out how to attach the platforms to the studwalls... any ideas on that?

Thanks everyone.

 

[Van]

Depending on the load you will be putting on these platforms you could probably get away with your stud walls being made from 1x4. as a matter of fact I prefer to make my platforms from 1x4 when building "traditional" types platforms. When using stud walls, or pony walls or knees walls < all these terms are sort of interchangable in a theatrical setting> it is important to add a diagonal piece of 1x4 material to add shear strength. You can assembly these systems a couple of ways. you can put the platform upside-down them lay the stud wall along the "stiles" of the platforms. Then using screws just put a screw every couple of fit thought the bottom of the top plate into the rail . Depending on the application you can sometimes just assemble the the stud walls on the stage then simply set the platforms on top of them with no real connection, just relying on inertia to keep them in place. This is not reccomended for plat forms that are danced or run on as the start and stop may cause the platforms to slip sideways off of thier supports.

 

[kicknargel]

I guess you don't even need a frame for the platforms if you use studwalls.

You absolutely have to frame the platforms--the studwalls are only acting as legs. The platforms should still be framed with 2x4 (on edge) around the perimeter and with internal joists no more than 2' on center (so there is no opening in the framing larger than 2' x 4'). The joints in the framing must be good and strong, as must be the connection of the 3/4" plywood deck to the frame. As mentioned, the studwalls require adequate diagonal bracing in both directions so they cannot "fold" like a parallelogram.

Not to be insulting, but I think I must recommend that you seek in-person assistance from someone experienced and qualified in the field.

 

[motek]

Thanks for helping, gentlemen - I have really learned a lot. Nicholas, I agree that there is nothing better than live help. I have been leaving no question unasked, so I'm sure I am sounding like a complete beginner. And compared to you all, I know that I am. Nonetheless, I did a lot of research online and still felt the need to ask some of these questions; I hope that this thread will be useful to other forum users in the future. I have not used studwalls before; nor have I done a traveling show - thank you for putting up with my questions.

Anyways - I will be switching to studwalls made out of 2x4's, using diagonal crossbracing as mentioned, with the top plate screwed to the 2x4 framing of the platforms.

This image shows the basic design I am going with:

Is it okay for the studwalls to be going on the three crosspieces as indicated? 12 screws per studwall (4 per plat)? Will these last through a couple shows? I suppose we can always move the screw holes if they loosen up.

Also, for assembly, we can attach the studwalls while the lower height platforms are upside down and then flip, but I am betting we will need to crawl under the 3 foot high platforms to screw upward, because there won't be a good way to flip those.

Either way I know this will be a lot faster than putting 120 bolts on 60 legs and ending up with "carriage bolt hell" after a few shows... so glad I avoided that!

I think that I am getting closer to not needing to ask any more questions regarding this - hopefully my slightly bowing platforms will make it through - thanks guys.

 

[kicknargel]

Looks OK to me, just make sure to run diagonal bracing between the studwalls (up and down on your picture) as well as within each one.

 

[Van]

Thanks for helping, gentlemen - I have really learned a lot. Nicholas, I agree that there is nothing better than live help. I have been leaving no question unasked, so I'm sure I am sounding like a complete beginner. And compared to you all, I know that I am. Nonetheless, I did a lot of research online and still felt the need to ask some of these questions; I hope that this thread will be useful to other forum users in the future. I have not used studwalls before; nor have I done a traveling show - thank you for putting up with my questions..

That's exactly why we do what we do here ! So keep asking!

Anyways - I will be switching to studwalls made out of 2x4's, using diagonal crossbracing as mentioned, with the top plate screwed to the 2x4 framing of the platforms.

This image shows the basic design I am going with:

Is it okay for the studwalls to be going on the three crosspieces as indicated? 12 screws per studwall (4 per plat)? Will these last through a couple shows? I suppose we can always move the screw holes if they loosen up.

Also, for assembly, we can attach the studwalls while the lower height platforms are upside down and then flip, but I am betting we will need to crawl under the 3 foot high platforms to screw upward, because there won't be a good way to flip those........

That diagram is an excellent example of how it shoud be done. Again, however, I'll state that you can save money and weight by constructing your stud walls from 1x4 but if you have 2x on hand more power to ya. Oh and screw the 16" centers for studs go for 18 or 24" o.c. again saves weight, and more simply isn't needed for most scenic construction.