I have to do one of these. Two halves of the Western Hemisphere on Gemini plastic. What is your method? Thanks, Jack
[ March 24, 2002, 08:13 AM: Message edited by: bronzeo ]
Posted by TransLab (Member # 470) on :
How large is the sphere?
Posted by bronzeo (Member # 1408) on :
36 inches
Posted by Monte Jumper (Member # 1106) on :
Is it so detailed you couldn't mask cut and spray?
I've strip patterned images like this before and used "Spraylat" as a mask...even if you took the time to hand layout the continents I would think you'd be way ahead of the game.
Seems like your asking for disaster here...But then bending vinyl onto compound curves has never been one of my favorite things to do...not even on a good day!
Posted by Ken Henry (Member # 598) on :
Hi Jack. I haven't actually done one of these, but my thought is if you attempt to apply a flat, 2-dimensional map to a 3-dimensional surface, you'll get so much distortion from stretching, that the map will become unrecognizable.
What I'd try is to break down the map into hexagonal shapes, and apply these individually. The pattern on a soccer ball, or a geodesic dome kind of arrangement. Each individual hexagon would be subject to far less distortion than 1 large map. You'll probably need the assistance of someone who has a strong mathematical aptitude, to work out the correct formula for determining the proper size of the hexagonal shapes, to give the proper coverage.
I could be wrong on this, but that's how I'd approach the problem. Hope it gives you a start toward a solution though.
Posted by Marty Happy (Member # 302) on :
Hi Jack,
I once did a three-colour logo overlay on one of those bubble fronts for a trailer. It took recutting and reapplying 3 times before I got it right and even then I wasn't completely happy because there were still slight wrinkles in the vinyl. I know I'm not being helpful here but determining where and how much to stretch is a trial and error proposition at best. Lining up overlays wasn't easy either but at least the elements were smaller and easier to work with. I couldn't see a way of using application fluid either because at least part of the graphic had to grip well in order to stretch/conform another area. I ended up applying, lifting a corner/section, stretching, applying again, back and forth over and over until it looked right and conformed to the compound curve.
If I had to apply vinyl to another bubble front or anything with a severe compound curve I would allow a LOT of time and charge accordingly or keep the graphic simple without a single large element that would stretch across a large area. If the graphic/logo had large single elements or colour(s) I would almost certainly project and paint it.
Sorry this does not really help but this is what I learned from my one attempt at something sphere-like. I would certainly be interested if someone had a brilliant solution to this question. Maybe a shrink wrap vinyl!(LOL)
Posted by Signs by Shawn (Member # 426) on :
I can't think of the name of the stuff, but there is a brush on mask that is used for lighted faces, you brush it on and it dries to a consistancy of soft silicone, I would brush this on, let it dry, draw my image with a permanant marker, cut with an exacto, (it removes fairly easily) then lightly blast the area to be painted to give it some bite, blow out excess sand, clean with rapid remover, or rapid prep, and then paint. Make sure to remove the mask before the paint is thouroughly dry to prevent any rough lines from paint pulling with mask, and then clear the whole thing with frog juice or dupont clear...
Shawn
[ March 24, 2002, 10:20 AM: Message edited by: Signs by Shawn ]
Posted by Stephen Deveau (Member # 1305) on :
Jack
This might work if you had longitude and latitude lines and cut in sections to apply.
I don't know as I have never tried this myself.
But I am with Monte on using spraylat mask,cut,and spray.
Good Luck! Posted by roger bailey (Member # 556) on :
Bronzeo, I had a call a few years back from a guy(Tom VanSant) who took the first photos of earth(miles from above). His problem (like yours) was getting a 6ft. sphere covered with this photo(outragious pixel count).
He cut the film in slices(like the lines of lattitude)pointed at top(north pole,and bottom(south pole),wide in the middle(at the equator).
This sphere was part of a very eloberate computor animation system(showing changes on earth,such as weather),worth upwards of $60,000.00. It had to be "right".
He used Rapid Tac of course !!
Hope this made sence, I'm up and off to the airport at 5:a.m. this mornin.
Roger Posted by Ken Henry (Member # 598) on :
Hi again Jack. Having re-thought this problem, I now think that if you first determine your equatorial circunference, (c = Pi x Diameter ) that will give you the longest dimension that your map has to be. Since you're only doing a hemisphere, you would half that number. If you have a distortion module, you could divide that map into 4 sections, and use those divisions as "meridians". Using your North & south poles as compass points, you can then determine the arcs that will be 1/4 of the distance from the equator to the respective poles. ( 1/4 of 90 degrees = 22 1/2 degrees ) You can now calculate the circumferences of the arcs, with the pole being a value of zero. having those dimensions, and using your distortion module, you should be able to make the proper distortions necessary to assemble this global hemisphere using 16 pieces for the top half, and 16 pieces for the bottom portion. This way, you should be able to recreate this globe with a minimal amount of map distortion. Your individual portions should resemble a trapezioid with the top & bottom lines curved in a convex or concave manner, the length of the top line, matching to and being equal to the lenght of each corrosponding bottom piece that you will be matching up to.
I hope that I've managed to explain this concept in a way that you can understand, and I also hope that it helps you out.
Posted by Brad Ferguson (Member # 33) on :
Cut and spray. Use Gripmask or Spraylat. I'm partial to the pink version.
Brad in Kansas
Posted by BRIAN CAISSIE (Member # 2673) on :
This might help? spere wraping Posted by Robb Lowe (Member # 2121) on :
Do you really need to do the whole thing? What about getting the globes molded in blue and use green or edge-printed HP vinyl? A little heat and a flexible squeegee, you should be set.
Posted by roger bailey (Member # 556) on :
Yes Brien, thats exactly what I (so un-articuletely) was trying to explain to Bronzeo !
Great job !!
Roger Posted by Mike McCloud (Member # 766) on :
wouldn't it be lots easier to just find somebody who still knows how to run something without electricity hooked to it and have them hand letter the thing? It's a 2-3 hour job. Keep it simple..........do it right..........
Posted by bronzeo (Member # 1408) on :
Actually Mike, I think I could probably handle that, but felt that vinyl might look better on this application. I had thought about the mask and spray for eveness, but realized their would be hundreds of little pieces of mask to get off without smearing and in a very short time. All the lat and longi lines need to appear.
I had viewed a post a couple of weeks ago where someone had wrapped the entire nose of a police car which had much tighter bends than the globe. I believe that they had used a heat gun with critical temp. I feel that if I get distortion, it will be on the larger continents and to the will be stretched out slightly. If that is the case I should be able to trim it back to its original shape pretty well. What is the spraylat, as I might find other uses for it? I notice several recommending it for a spray mask. Wouldn't I have to use Gripflex a like material for the paint on the plastic sphere? Thanks, everone for try to figure this one out for me. Jack
Posted by Talisman (Member # 1869) on :
Hi Jack,
Just thoughts...
You could paint the whole sphere ocean blue. Then edge print the individual continents and place them one by one with minimal distortion.
Now the longitude and latitude lines… a fine striping brush and a really steady hand
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