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Posted by englee, on 2009-10-07 12:08:08
Magnetic tie-down set
I plan to use magnetic tie-down again in my next animation but have some questions.
Last time, I tried building a set with metal floor and covered by thin surface (don't remember what it is). The problem I had is that I can't pose my puppet with the foot about 3/4 inch above the floor. The metal surface will suck the foot to it right away. I either have to put the foot all the way up from the floor(like an inch) or all the way down.
I just wanna know what is the standard set building method for magnetic tie-down technique, and if you can pose the foot about 1/2 in above the floor?
(Link to my previous animation that got tremendous help from this awesome forum):
Posted by Nick H, on 2009-10-07 17:30:08
The way they did it at Cosgrove Hall (studio in Manchester, UK, makers of Wind in the Willows, Truckers, Fool of the World and the Flying Ship, The Pied Piper) was -
The magnet goes under the set floor. The puppet foot contains a steel plate, but no magnet. This way, the foot can go as close to the floor as you like, and it only sticks when you put the magnet in - just like a threaded tie-down.
Their magnets were tall cylindrical rare earth magnets, and so strong they needed a screw up the centre to push the magnet away until it was far enough to weaken the grip.
For my films, which usually have rough ground, I prefer actual bolt tiedowns - so I don't know where you would get magnets like that.
Posted by alex uranga, on 2009-10-07 18:38:42
Here's a link I found on stopmoworks http://www.kjmagnetics.com/ . Not sure if it has those magnets, but I guess it's worth a look.
Posted by LIOs Nephew, on 2009-10-09 18:25:23
Only works if surface miniature set/stage is basically FLAT. Use of flat [b]perforated[/b] sheet steel so magnet force flows through holes to better grab puppet feet. Also, holes in sheet steel can be used for back-up screw tie-down. About thickness of paper covering sheet steel. If covering too thick, less magnet force to hold feet. Best if puppet design has kinda BIG feet. Will not work for top heavy, tiny feet puppets. Also, armature tension kinda LOOSE. Feet can slide all over if armature too stiff as you're animating.
Can be pain in butt to make this type of sheet steel perforated animation surface. First, finding where to buy. Then, if big animation surface area, sheet steel needs support underneath so it will not bend in middle.
"Thank me" for giving everyone powerful learning moment (Being taught by Uncle LIO)
"[b]I'm just a Kid, so don't yell at me[/b]™" :P
Posted by grecodan, on 2009-10-09 11:47:54
Forgive me for being an old nanny for a moment, but a word of caution:
If you choose to use rare earth magnets, please be careful! Those suckers are strong! If you get a sufficiently large one it could quite easily crack a bone in your finger if your hand were to get between the magnet and, say, a refrigerator door or something.
Posted by Nick H, on 2009-10-09 18:48:21
I used perforated steel for a set floor once, and like Lio's Nephew says, it needed a lot of support to keep it from flexing. Particle board would work fine just sitting on the 600mm x 1200mm (2 ft x 4 ft) frame of the rostrum, with no support in the middle. But the steel needed a bit of framing under it every 200 - 300mm (8 to 12 inches). I kept finding those bits of framing were exactly where I wanted to put the robot's feet. A couple of times I moved the frame in the middle of a shot so I could put the tiedown in.
In this case, the look of the steel suited the set design so I didn't have to conceal it.
I didn't actually use magnets here - perforated steel works for both kinds of tiedowns. If I wanted a floor like that again, I'd put a sheet of particle board under the steel, since I'd be using my T-and-Slot tiedown system, and drill holes where I needed them. If it had to be magnets, I guess framing could have been placed under the ducting laying along the floor so the robot would naturally step over it.
Posted by Sasquatch, on 2009-10-12 12:25:51
That's a cool frame capture Nick, what film is that from?
Posted by Nick H, on 2009-10-12 19:44:06
That's from a comedy series called Daas Kapital. It featured DAAS, the Dough Anthony All Stars, a standup musical/comedy trio, and was set aboard a bottom-of-the-sea installation that was blown into space in the second series. One of the characters was spewing up foam balls in this episode - this is the ship's cleaner robot clearing some up.
A sample from another episode, with my little devil puppets, is in my "favourites" at Youtube. It won't make much sense by now - it barely did back then. But it was a hoot to work on. I designed and made props, and special costumes (like giant mutant cockroach, mermaid tail, Mr Potato Head suit where the wearer was impaled by the spikes on the ears, eyes, nose etc). On weekends I shot little animated inserts featuring Thulgor the monster in the pit, Ross the Cockroach, and the cleaner robot. Each show had less than a week to write, make everything, and record. I guess it could be described as a blend of cabaret and Red Dwarf, on 1/40th of the budget. Which shows - the performers were also the writers, so there was no time to refine it.
Posted by JET, on 2009-10-12 23:13:52
I just got 4 rare earth magnets, and they are too powerful. It is very easy to get my finger hurt. The size is 20mm diameter and 33mm tall. I think they are strong enough to support the foam latex puppets with the floor 5mm thick.