URGENT theatrical flat flying question- URGENT, ASAP!

jdsilverm

Member
Hey everyone,

I can't believe this happened, but it did: our standard bottom hanging irons don't fit the depth of the bottom of our theatrical flats. I did a thorough google and CB search, but I guess it seems no one has ever had this problem before (which I find hard to believe). I have included some pictures for your convenience, but basically our flats seemed standard, with the traditional 1x3s, 3-ply plywood fasteners, and 2.7mm Luaun top. But, when we attempt to put the bottom hanging iron on, the depth of the 1x3, plywood, and Luaun won't fit in! We've read everything about flat construction, ordered all the correct stuff from Sapsis Rigging, and have built everything solid. But we never expected this shenanigan since this is the only bottom hanging iron Sapsis (and other vendors) seem to offer, so we assumed they would fit the standard flat construction guidelines published everywhere!

Would anyone please assist us ASAP with ideas? Everything is already built and assembled. We thought of cutting a small piece of the Luaun off the top layer for just the tip of the hanging iron to go around, but it's still a mm or two thick. And all our plywood fasteners are screwed in and we feel it would jeopardize the integrity of the units to cut chunks of those away. What are some options?

Thank you so much in advance for your advice!

Jeremy

Here is a link to the sample photos:

https://photos.app.goo.gl/T6nXLz3pM7hYfFm59
 
Yep take off a layer of luaun. Then plane/sand the back to make it fit. Then thru-bolt it like usual.

Also your picture doesn’t work on my phone.
 
Amiers is right, but they can't see your photo, so they didn't see the plywood corner blocks that are causing your problem. The hanging irons will fit around 1x and luan just fine.

BMI says their hanging iron supports a max 1" rail. Looks like you've got at least 1 1/4" going on there.

To solve your problem, you gotta remove some wood. Easiest is probably going to be from the front, so buy your painters something nice and carve into the luan to make room for the hook. You'll have to take out some of the 1x as Amiers said, and you might find that easier with a chisel given your construction.

You could also bolt on some shackle plates.
 
I think oh hanger irons for typical flats with just muslin, and don't think of hard coverings when framing is flat vs on edge - "Hollywood" style flat. If the luan is glued, you simply don't need the corner blocks - the luan does that fine.

I'd probably use a router with a box bit the width of the hanger and hog it out on face. But a little chisel work would work.

So are traditional flat frames with corner blocks often hard covered? Seems redundant.
 
So are traditional flat frames with corner blocks often hard covered? Seems redundant.

I’ve built a few broadway style flats when space or aesthetics was a design factor, and I’ve definitely built more hard cover Broadway flats in my professional career than soft cover. Haven’t honestly used soft cover regularly since high school. What I have done much more regularly is built steel flats, skinned in luan, then stretched in muslin and dutched with white glue.

When built on face, without some corner blocks on the back a hard covered Broadway style flat will split and splay at those seams. You need something on the back to keep everything, well, flat.
I think that’s one of the big advantages of Hollywood style flats in that they eliminated the need and hassle of corner blocks/keystones. Well, that, and the fact they can be easily bolted together.

However, if you used some corrugated staples/wide crown staples/really long screws/biscuit joiner/mortise & tenon, THEN they’d be redundant.

OP, honestly, if the luan skin is properly glued and stapled on, I personally feel fine top hanging those flats. Just be sure to use #10 machine screw hardware and not drywall screws to attach them.
 
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Even though they're luan covered I wouldn't top hang them. 1) it's just not as safe, 2) the flat will tend to lean while if bottom hung it will be closer to straight up and down.
 
I prefer flat hanging irons since they are a bit more universal. I have a mixture of 1x3, 1x4, and a few other random sizes but most of them are Hollywood (edge framed with luan). I use flat irons (the strap kind with a forged D-ring) bolted through the rails near the bottom. That way I can use the same irons on all my flats.

I also have some like yours, but they have a square bend at the bottom. I cut off the return leg of the iron so that it is just a 90 degree bend, then drill a hole in the bottom. It still gives you the added safety of the steel under the flat, but doesn't discriminate on thickness.

So I have some of these for my hollywoods:
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And some of these for my Muslin, but I cut off the last bend

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Hey everyone. Thank you all so much for taking the time to reply. SO much great information, and resources I didn't think about in the first place.

Because some of our flats are heavy (but solid and very well built in case you were concerned) what we have decided to do is keep everything as is, but Dremel out the very edges of the 3-ply fasteners where the bottom hanging iron will go. Seems to be working well. Most screws will even get to stay in, OR, better yet, the hanging iron screws will take their place anyways!

It's obviously a pain in the butt and and a classic "live and learn" scenario, but it is what it is and we have to load-in tomorrow. Interestingly, literally every book we have read on the subject, from well-known names in the rigging/theatrical biz, never mention this concern. They all share how to build traditional Broadway-style stock flats, fly them with traditional hardware, etc. But no one mentions the fact to be careful adding up layers as they may preclude the bottom hanging iron fitting. Even in pictures all I see are 1x3s, 3-ply plywood fasteners, etc. Very weird.

Anyways, thank you all again. I'll try and post some pictures of our solution so perhaps we can be of help to anyone else facing this issue in the future.

J
 

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