Fake Full size Lightweight I-Beams/ Girders?

[SgtFang]

I just had a great decorating idea, but I need to come up with a cheap way to make lifesize girders/ support beams. The straight sections should be fairly easy, but I want the ends to flare out into 2' arcs that go on the ends/ corners.

any suggestions?

Thanks!

-Sarge

 

[booger_viper]

I've seen them done pretty convincingly before out of wood boards (don't know dimensions) and then dowel rods implanted to be the bolts.

It's really the panit job that does it and the ones I saw had a nice fake rusting painted on them.

 

[SgtFang]

Yeah, the straight, flat parts shouldn't be an problem at all, but I'm stuck for a material to do the curved, flat part under the arc. It needs to be about 1/2" thick, but able to follow the curve on the undersides of the end pieces.

I just re-read that and it sounds confusing even to me- I'll try to put up some quick drawings later to show what I mean. :wacko

-Sarge

 

[PTK]

i think i might know what you mean.....like where the straight parts of the I beam intersect isn't a sharp 90 degree corner, but more beveled like this

what i would do is build the I beam out of wood then get a piece of flat plastic (like styrene, but more towards the thicker side like .060 or .080) make sure the edge of the plastic is a perfect 90 degrees (and make sure your I beam is pretty perfect too) then cut out the negative shape of how you want your bevel/transition to be, then get some bondo, smear it along the corner, and scrape your plastic template over that to shape it

some tips/pointers:
to save time and money if the bevel is more than .25", glue a strip of wood in the corner to take up some of the space so you don't have to fill the entire area with bondo
bondo kicks pretty fast so do smaller sections instead of trying to do it all at once
maybe have a spray bottle with acetone handy, apply your bondo, swipe it with the plastic, clean off the plastic, then give the bondo and the plastic a fine mist of acetone and re-drag the plastic to get a smoother finish (note: too much acetone will leave the surface of the bondo a little tacky but its not a big deal)
you can also mix up your bondo, throw it in a sturdy ziplock bag, shake it until it gathers in the corner of the bag, then snip the tip of the corner off and use it like a pastry/icing bag to apply the bondo faster and more consistently before you swipe it
be careful, some types of plastic disolve with acetone, and some will even get a little soft with continued exposure to the resin in bondo

hope that helps......and if you were talking about something completely different then i just wasted my time

 

[SgtFang]

Here we go-

I want to make a few of these going across the ceiling of my Jules Vernian style library.

Most of it will be a cake walk, but the red part is throwing me- I can't think of anything thick enough that will still be easy to form that curve with, that will still paint up like old steel.

-Sarge

 

[SgtFang]

Here's a VERY quick sketch to show how they will go on the ceiling-

-Sarge

 

[CGClone]

Hey Sarge,

Could you not get some of the pink 1.5 inch thick sheets of house insulation boards at Home Depot? They sell a coating for that, I will dig up the links for you tomorrow. Or some modeling boards, but thats very expensive.

Just a thought.

 

[acerocket]

Beams like those are usually welded from sections of flat plate. If you wanted to do it in wood, the straight sections would be easy from plywood, etc. For the curved sections, how about the flexible form boards concrete masons use? Or, if they are not size prohibitive, you could soak and bend thinner sections of something like 1/8 or 1/4 pine and bend over a form to get your curve, then glue together to get the desired thickness.

 

[patsmear]

Use real Girders....ya pansy!


Pat

 

[stapleton13]

You can get fiber board, and cut it into strips Then soak it in water for a day or so. It gets very easy to bend. You can then clamp it to a form, and let it dry for the curve. Also I have seen welds made with a hot glue gun.

Hope this helps give you ideas.

 

[SgtFang]

For the curved sections, how about the flexible form boards concrete masons use?

That sounds intriguing! Tell me more! Do you know the trade name for it so I can ask about it next time I got to Lowes?

You can get fiber board, and cut it into strips Then soak it in water for a day or so. It gets very easy to bend. You can then clamp it to a form, and let it dry for the curve. Also I have seen welds made with a hot glue gun.

Hope this helps give you ideas.

I've never used fiber board, I'll ask about it next time I'm out. :thumbsup

Could thick masonite be soaked and formed? Or would it just get all swollen and deformed?

-Sarge

 

[Tiki]

That is too funny - I've been puzzling over a similar idea - but I am more along the lines of big beams of wood to make my office look like it is in an old ship. Same deal though - how to get the curved top piece. In past home improvement projects I've had great success ripping a bunch of perpendicular cuts along the length of the board you want to bend. Dont cut all the way through - just 3/4 of the way through. THen you press it in place (with the cuts facing in to the bend). The cut lines can be easily filled with bondo - or you can make your girders "double walled" so you won't see the back of the bent board. Hope that all made sense!

Also should add that the "tenament" set for spawn had a ton of fake I-beams with massive bolts. They were all fabricated out of plywood with a thick and heavily textured layer of paint over them to simulate a pitted rust texture. The art dept. molded one massive bold end with a huge nut on it, cast a ton in rigid foam, and glued them all over the plywood i-beams. With the texture, rust color, and nuts/bolts they looked fantastic! Too bad the movie sucked

 

[exoray]

With a little hot water/steam and a form you should be able to bend a good furniture/marine grade 1/4" plywood without any issues, around the radius you show... Soak the piece in the tub in hot water and place in the form and let dry...

Or visit a real lumberyard (you are going to want to get the better plywood here anyway) and inquire about flexible or bendable plywoods, they do exist for just this purpose... You might find them calling it "[SIZE=-1]wacky wood" or [/SIZE]"wiggle wood"

If you need it bigger/thicker then then laminate several sheets, and glue them...

 

[RGPFX]

Here we go-

I want to make a few of these going across the ceiling of my Jules Vernian style library.

Most of it will be a cake walk, but the red part is throwing me- I can't think of anything thick enough that will still be easy to form that curve with, that will still paint up like old steel.

-Sarge

I'd use Sintra (PVC sheet) It comes in a number of thickness from plastics suppliers, glues and sands and cuts easily, and takes paints with no problem. Unlike wood, there is no grain to deal with, but edges do have a slightly pebbly texture if you look very closely.

RGP

 

[Snowflake]

definitely go for sintra, you can use 2 or 3 3mm thick sheets glued toghether (sanding the edges is fairly easy)... it holds bondo, fiberglass, resin, paint... everything very well!

 

[RGPFX]

definitely go for sintra, you can use 2 or 3 3mm thick sheets glued toghether (sanding the edges is fairly easy)... it holds bondo, fiberglass, resin, paint... everything very well!

If you heat it with a blow dryer, you could probably bend 1/4" or thicker, no problem!

 

[Great_Bizarro]

Sintra or pvc sheet will work You can heat in hot water too if you don't want to risk starting it on fire.

 

[acerocket]

That sounds intriguing! Tell me more! Do you know the trade name for it so I can ask about it next time I got to Lowes?



I've never used fiber board, I'll ask about it next time I'm out. :thumbsup

Could thick masonite be soaked and formed? Or would it just get all swollen and deformed?

-Sarge

Don't know the exact name of the form boards, but they are usually 1/2" wide or so and 6-8" tall. They usually have slits cut about every foot about 3/4 of the way deep. It didn't dawn on me that you could make them yourself by cutting slots in the back of your wood. Easily fillable with bondo as Tiki mentioned in his post.

I think masonite would fall apart if soaked.

 

[Gigatron]

If these beams are not structurally integral to the room/house (i.e. just decorative), why not just make them from large blocks of foam?

Contact RileysReplicas and ask him wher he gets his large blocks of carving foam. Get the blocks, carve them to shape, give them a quick overlay of fiberglass (like the repair stuff you get in autoparts stores) for rigidity, then paint them to look like rusty iron.

There's no need to make this tons more difiicult with bending jigs and steam rooms.

-Fred

 

[FETTCLONE]

For those of you looking for a wooden material to make curves I suggest snake ply, sometimes also called wiggle ply. It's essentially plywood made with the core woodgrain running in one direction and the other layers running perpendicular to it. When the outer layers bend along their grain the core layer supports them (because its grain runs opposite) enough to allow bending but not breakage. It comes in either direction (bending parallel to the 8' side or bending along the 4' side of a 4' by 8' sheet. There are many thicknesses available. The thinner the sheet, the tighter the inside curve you can make.

Or, just cut a bunch of bending kerfs as mentioned earlier. This is more of a quick-fix, "it's worth spending a few bucks to save the time and effort" suggestion. Might be worth looking into for some of you.