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Hello, this is my first post on a very interesting site with an amazing mix of items in the gallery. I didn't realise that PM could be used in so many ways, I'm particularly impressed with the furniture that is created by the cartonnistes in Paris.
Besides newspaper, brown paper etc have many people used say glassfibre tissue or fine hessian/scrim cloth as a material (;-) to use.
Just wondering if their is a shortcut to creating a hard surface rather than building up numerous layers of paper? Or using say a combination of two materials? I may have to go away and experiment but it would be interesting to hear other peoples experiences.
TIA
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Well i have no idea about glassfiber but usually when I want a solid surface a take a lot of towel paper and mix it with white glue (no water) but not to much or it will give a hard to manage consistence. I wet the tip of my fingers with water so they dont stick while I give the shape i want to the piece. It will still take some time for you may need to let it dry before you can continue with other parts, I hardly use the layer method anymore only for the final surface I have found this method more effective for it gives you a harder surface in much less time and effort. Hope it helps you. I know i said a lot of towel paper but it depends for what you want it.
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Rags, thanks for the reply.
I don't want to create a shape with PM I just want to cover a surface, I'm not that creative yet!. I have a cut the shape of racing motorbike out of foam it's approx 4' long x 3' high and 12" deep and want to make it hard wearing (for use as a seat in a boys room). Would you recommend dipping full sheet of kitchen towel into the glue or would you cut strips and laminate it that way?
TIA
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Well Ive never done something that big before, kind of a newbee on all this, but if somebody is going to sit on it definetly needs to be something much more stable than paper.................it would help if i could see how it is. Got a pic, maybe I can show me dad he is good with structures and stuff.
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Here is photo of the bike, the actual one would be a little deeper.
or
http://i121.photobucket.com/albums/o209 … GPseat.jpg
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Wow, Foamcutter . . . that is one big and neat armature. Is it from polyurethane? The 'Hollywood' site you link to is interesting. I'll spend some more time looking at it.
I am using foamed board quite a lot recently, though on a much smaller scale than yours. The material I use is a different formulation and is used for insulation in buildings.
The method I have evolved, which is working incredibly well, is to form the armature with saw, rasp, file and sandpaper. Then coat it with slightly diluted PVA, which seals the surface. I then apply a fine pm mix that dries as hard as stone. You can look at the recipe in Martin Favreau's article or email me your telephone number and I can talk you through it. I lay this at about 2-3mm thickness.
I suppose a question would be - how strong is the foam in its own right? Does it need any reinforcement in order to take a person's weight?
If it is only surface cover you want, then paper layering, with strong kraft paper and PVA to about six layers, should be OK. With either of these methods you would not need fibreglass mat etc.
DavidO
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Dopapier, thanks for your comments and information.
I'm lucky that I have access to a CNC machine that cuts polystyrene foam, that's the reason the shape is so neat. It won't cut polyurethane unfortunately.
I think we are going to have to do some experimentation with paper, material etc, I was hoping to pick a few brains and learn from others before we make the same mistakes. Most of the items we work on are large, a friend has just completed a pair of cupids (in foam) about 24" long and covered them in a single layer of tissue paper. This was just to cover the foam and not for strength. That why I searched for pm and came across this forum/site. I will post photos when I see them this weekend.
As for strength, people are constantly surprised how strong foam can be.
This chair is just raw foam just painted with emulsion and it will easily take my 80kg weight, I can even jump on it. Ok, foam doesn't suit thin spindly legs BUT it might with pm, we will have to wait and see.
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Impressive stuff. Actually, I meant polystyrene. I also found you on the product design site so can see what you are skilled in.
I think you may find that one of the paper methods will work for giving strength to the chair legs but, as you say, you will need to experiment.
A laminate of alternating kraft and bond paper to at least six layers can be very tough. Use carboxy methylated cellulose mixed to a workable paste (or next best wallpaper paste), with about 25% PVA. One of our sages, Sue (catperson) would not use PVA but I always do. Try it out!
DavidO
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Cheers David.
We have both PVA and wall paper adhesive in the workshop already. I will have to make time and play around a bit. The chair isn't a "to do" project, the bike seat is hanging around now for months so I'll give that a try first. I do a small scale to start and see what works best.
Toughness is relative to the substrate, foam is relatively soft so I tend to use the finger nail test to see if I can indent the surface. We will see how pm works.
Thanks again for the information.
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Here is an image of a cupid as promised.
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That's a very effective Cupid. Presumably the wings are not based on foam?
We'll be very interested to know how you get on with the surface laminates.
DavidO
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The lady that made the cupid used wire to form the wings. She was quite ruthless when working with the foam armature, the cupid was decapitated with a hand saw and the head repositioned. The PM covers join.
Will post the results of the laminating tests when I get finished painting shamrocks for St. Patrick's day.
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