Need shape-able foam board blocks..anyone have experience w/ this ?

I am looking for the best shape-able foam material......I have been looking around on the net......I am finding allot of stuff....But was wondering if anyone played w/ any of this stuff before ? and what did they use and where to get it........I will be mounting the Roadster body soon to the chassis....Then will take a bunch of measurements and remove the chassis from the table, but will mount the body to the table as if it were still on the chassis...I was thinking of shaping the nose out of foam blocks until I was happy w/ the shape......Then make an all aluminum nose for the body per the shape.......shape the foam, maybe make a wooden buck and start forming the aluminum.....I have a way to go before I get to this, but need to stay ahead and on top of things, would like to buy what I will be using....Thanks, Littleman

 

Check around the construction industry. The current fad involves foam shapes with stucco over them to put a little detail in the homes.

Charlie Stephens

 

My Friend made this buck/mold form for me.
polyisocyanurate foam insulation sheet.
aka, thermasheath. 1 1/2" thick sheet from homedepot or lowes.
glues up with hot melt glue, shapable with rasp and takes plaster paste fill. We then primered it, waxed it, gelcoat and then resin and mat.

John

 

You could use the pink or blue foam that they use under cement. Gorilla glue and clamps to glue pieces together to make a big block of it. Then you can use a saw and 80 grit sand
Paper to form it from there. I use it all the time to make molds for boat parts. I will snap a pic of some molds I made for a wet exhaust for a boat I built.

 

Look for polyurethane foam blocks. 12lbs density should work well for hand forming. These foams can be made yourself with 2 part urethane liquids and poured in a mold of a box, just watch that it can handle the heat the foam produces at it sets.

 

I've done very similar to this. Works good and not expensive or time consuming.

 

Have you ever seen the foam pillars and trim they put on buildings before they stucco?
I use to work by a place that made that stuff ….. They start w huge blocks of foam just like you need.

 

Aircraft Spruce in California supplies foam for making composite airplanes and has a variety of foams suitable for what you need. They sell most of their stuff by mail order so shipping the foam won't be a problem. They also have a lot of other neat stuff that can be used on rods and their catalog is free.

 

We ( Terry Hegman and myself) used foam to shape the top for my roadster . I found the foam at McMaster -Carr catalog , it was in 4x4 sheets 4" thick which I glued together to get the right thickness. After shaping we made a cut down the center , and then moving outward , made 2 more cuts . we then used that profile to mark the plywood that would become the buck. I don't have any pics of the foam or buck , but here's a few of the fabricated top . Good luck with your project .

 

I've used a lot of blue foam for shaping RC airplane wings and fuselages. Sands really easy, is durable, you can lay glass/kevlar/carbon up over it if needed.

Get a snap blade knife for roughing out the shape and a few sheets of drywall sanding screen to clean it up. Then if you really need to get it smooth use lightweight drywall spackle to fill in any of the minor voids. You can get it perfectly smooth and ready to pop a few parts from.

PM me with any tech questions. I have a ton of links I can send to you.

NAES

 

This is a good place to go....http://www.fibreglast.com/category/Foam

 

Sign foam is easy to work with and will retain it's shape.

Available at any commercial sign supply house.

 

When I did the body mods on my roadster ,I went to a florist and got this green foam.. It was cheap,mst of it was cutoffs from a larger sheet.. Don't have a clue as to the type/designation,but it hotglued & sanded great.. Formed it with 80 grit paper ..

 

If you are looking to fabricate a hammer form, I would skip the foam step and go right to building the wooden form. Foam is a great way to form fiberglass or carbon fiber. But that does not sound like what you want to do.

 

What he said, urethane foam or a variation of it is what many of the other suggestions are also referring too.

 

I love the top on this car! You guys did an outstanding job building that.
Dave, they have you covered. I have done the same in the past, messy, but a great timesaver!

 

Thanks for all the ideas !........I did research this prior...but was wonder if anyone messed w/ this here...nothing beats real world experience.......Thanks again, Littleman Dave

 

Often called Oasis, or floral foam.

 

Make your own foam in shapes you make out of plywood and lined with wax paper. I use high expanding spray foam in the can from Home Depot. Different expansion rates. If it expands 2x then fill the shape 1/2 full and it will expand. I think there is a 10x can.

 

I had a similar dilemma recently. Found out that you can stack sheets of waffle board (OSB) with Gorilla glue between each layer and clamp it altogether. When its dry, you can sand, disc, cut it into any rough, very strong, shape and hammer your heart away as you shape the metal around the form you create.... Its tough and not easy to destroy. Make the form blocks in sections, mirroring one half to the other. Hammer your metal. Stitch weld the center line when you get it formed the way you want. I would not use foam. Too Dang'd light. Try a test piece out of OSB. Think you'll be surprised!
Hope this helps. Let us all know which way you decide to go! Happy New Year!

 

Forgot to mention, using a disc grinder is fast way to whittle it down using coarse disc's. The OSB will sand to a very fine finish with finer sanding disks. I had some really tough curves to deal with and after I got the form finished up, I heated my metal sheet and laid it over the form. It smoked, but held up nicely and I hammered my metal, occasionaly heating it with a torch to keep working. Not too hot, or you will get a fire!!!! I was making a dashboard.

 

You might want to check some of the model railroad sites, they use foam extensively for landscaping. Try the "Trains" site for their model railroad magazine for tips on cutting and shaping. Many use a hot wire that the heat and cutting speed is controlled by a transformer.

Good luck with your project.

 

I was only going to use the foam to get the shape desired and it gives you a graet idea of what it will really look like..then make a wooden buck of the same shape to form with.......I could make a wire form as well...I have made small parts this way...just never something this large...Thanks again for the all the info offered...Littleman Dave