By Susielou from Doncaster, UK
You can often get inexpensive remnants from places like Jo-Ann Fabric or other fabric stores, or in fabric departments in places like WalMart.
See if you have a local chapter of the Project Linus Blanket organization. My mother's group usually has a "blanket day" once a month at a church. Contact the head of the group and explain what you need. I'm sure they would be willing to let you come pick up their scraps at the end of their meetings or they could save them for you. http://www.projectlinus.org/
The single most important thing to keep in mind when looking for materials, no matter the source, is to keep the scale correct. Nothing ruins a miniature like something out of scale. There, now that soapbox can be put away and your actual question addressed.
Goodwill, etc. often have fabric bundled on the cheap, though most of my scraps for doll making (and miniature work) come from thrift store clothing as previously mentioned. I get beautiful scraps of wood; rosewood and teak are very common, metal and plastics from the local marinas. They're used in boat building. I've even snagged glue on occasion from them! Paint is now sold in "tester" cans at the hardware store, and is the perfect size for use with miniatures.
More than anything else, though, I use my imagination to think of ways to create what I need from found objects and materials. Always remember when creating miniatures that you don't need to make an exact replica (unless that's your specific intent), but rather need to make it LOOK like a replica. This paper or plastic or even stiffened fabric can often serve as wood, polymer clay is miraculous material from which to create anything from toilets and tubs to hairdryers and fruit! And you can paint the stuff with a alcohol-based marker, too!
Most of the posts have been for FABRIC material. For wood materials (for the making of mini-furniture, go to your local cabinet maker. My boyfriend is a cabinet maker specializing in custom work, and has to throw out scraps of wood all the time. These "leftovers" are great for making all sorts of things from window boxes, planters, scroll-saw cutouts, etc. We give the sawdust from solid wood, NOT plywood (plywood has glue which is toxic to animals), to friends who have pets which they use for pet bedding. Another friend uses solid wood shavings for his compost pile. Recycle, recycle, recycle!
Some of my best fabrics have come from clothes that I got from thrift shops and yard sales. The benifit is that you often get buttons and zippers, too. If you love a blouse then keep the body, making it into a vest, and use the sleeves.
You can often find remnents at Walmart and other craft shops as well.
Contact a ladies' tailor or someone who does alterations. They will have scraps and probably throw them away. The quilter's idea sounds good, too.
Try asking for material scraps on Freecycle.net. If you have friends or relatives who sew, ask them.
Yard and garage sales and a good will store is where you can get a lot of material items reasonably and can be cut up to smaller scale and make lots of doll house minis.
Find out where quilters or sewing bees are held to hopefully get mini pieces of fabric from them.
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