There are several types of glue available for basting. Some of them are formulated especially for the quilting industry and some of them are manufactured for other uses. There are advantages and disadvantage of each that I will discuss in the paragraphs below. With the use of these products thread basting is eliminated.
One product is called Roxanne's Glue Baste-It! It comes in a small bottle with a long neck applicator so a small dot of glue can be placed on the fabric. The instructions recommend a small controlled dot of glue be placed 1/2" from raw edges of fabric. It will hold firmly until fabric is wetted. Once your appliqué project is glue basted you will be able to stitch needle turn appliqué quickly.
Acid free glue stick is available in the school supply section of most variety stores. Glue sticks are priced very reasonable. These are put up in a plastic tube that is similar to lipstick. There are several brands available and you will have to experiment and decide which brands you prefer. Be sure to buy a brand that is washable.
Some glue sticks say they are permanent yet washable. In this case the permanent refers to using them in scrap booking or other paper uses. If you use them on fabric and the glue is washable, it will wash out of your quilting or appliqué project even after it is dry.
A swipe of the glue stick on the fabric or freezer paper will hold the fabric in place until it is wet.
Store your glue sticks in the refrigerator, preferably in an airtight container or a zipper seal bag. When one glue stick gets gooey from using, place it back in the refrigerator and use another glue stick that is cold. Continue rotating glue sticks until you have finished basting your entire project.
I prefer glue stick that is white and dries white. Some glue sticks are purple but dry clear. Many quilters use this product but I prefer not to risk having some of the purple color remain in my fabric after glue basting.
Elmer's School Glue
School glue is water based and it washes out completely. It is readily available at most variety stores and now there are even applicator lids that can be purchased. They are compatible with the school glue bottles. You would fine the applicator lids at your local quilt store or hobby and craft store.
Temporary Adhesive Spray is available in an aerosol spray can. Temporary adhesive spray is repositionable. After 2-5 days the glue will disappear leaving no residue. This type of spray should be used if you are going to work on your project within a few days.
Basting Spray will hold indefinitely until it is washed out. It needs to be washed to completely disappear. The aerosol sprays can be a little messy to use as when applying them there will be an "over spray". You either need to protect your spraying surface or you will need to do some clean up when you are finished basting. Most basting sprays clean up with soap and water.
Whatever product you choose, you will need to wash the glue out of your final project. When I finish an appliqué block, I usually soak the finished block in a small basin of warm soapy water. In a few minutes the glue has softened and the block is ready to be rinsed and hung to dry.
Fusible Interfacing For Piecing
Watercolor artists have been using fusible interfacing to assist in piecing for several years. Fusible interfacing is available with a one-inch or two-inch printed grid depending on the brand you purchase. This grid interfacing is available at fabric stores, superstores, and your local quilt shop. If you buy pre-printed interfacing you won't have to draw the grid yourself.
If you cannot find interfacing with the grid you can make your own by using your acrylic ruler and a permanent marker or a ball point pen -- anything that will write clearly on the interfacing.
This interfacing is the grid is printed on the non fusible side. Sometimes if you are working on a dark surface the printed lines do not show through adequately. A good way to overcome this would be to place a large sheet of white paper under your fusible grid. Also remember if you are drawing your own grid you will also want to draw on the non fusible side.
To design your watercolor, the fusible grid interfacing is placed fusible side up on the table. The watercolor fabric squares are placed in a pleasing manner. When the design is completed, slip a bath towel under the interfacing and iron right on the table to tack the fabric pieces in place. Once the pieces are tacked, you may then move your piece to the ironing board for a more complete fusing.
The printed interfacing grid is already printed in one inch or two inch increments. That being the case you will want to cut your watercolor squares slightly smaller or a scant two inches. Once the fabric is fused it will be easier to fold the fabric to stitch.
Sewing the grid
The interfacing backing with the fabric pieces are then folded with the fabric right sides together and stitched on the machine. After stitching all seams in one direction, the seam allowances are clipped where the fabric butts together. Then the fabric is folded -- again with right sides together -- and the squares are stitched together in the opposite direction.
One drawback of using fusible interfacing I have noted. Fusible interfacing has a directional stretch that will make your piece slightly rectangular. On a fairly large piece you will find a square is not square but slightly rectangular. I simply made adjustments in the borders and didn't mind that one direction was slightly larger than the other.
The interfacing is left in the project permanently so it would definitely need to be machine quilted and not hand quilted. There is a stiffness left by the fusible glue and the additional layer of interfacing but if you are simply making a wall quilt the extra stiffness wouldn't be significant.
Another watercolor landscape artist uses tear away stabilizer for the same purpose. Tear away is not marked with a grid but can be easily marked with your acrylic ruler and a ball point pen. The theory is the same. You mark your grid -- she recommends 2 1/4" and cutting fabric squares at 2". Because the tear away is not fusible you will need to use acid free glue stick -- the kind used for paper -- to glue the squares down.
You don't need a lot of glue for this process. Simply swipe the glue stick along the stabilizer and place your squares. If you need to iron your squares it will be OK. The heat from the iron won't hurt the glue or fabric.
These squares on the tear away stabilizer are folded and stitched in the same way as with the fusible. Stitch with a short stitch -- about half of what you would usually piece with. This will help in tearing the stabilizer away. After sewing all seams in one direction the stabilizer is removed from the seam allowance only. The project is refolded and the opposite direction and the rows are stitched. Again tear away the stabilizer in the seam allowance but leave the stabilizer in the main part of the quilt until the borders are added. Then tear away the remaining stabilizer behind the squares. Any small amount of glue residue on the fabric will wash out the first time your project is laundered.
Recently some new patterns and booklets were released using a quilter's grid printed on point. They contain instructions to piece nine patch or other simple patterns using a fusible interfacing grid. Again you do not remove the fusible interfacing and would have the bulk and thickness remaining. This concept might be useful for some patterns. Most of the patterns presented looked simple enough to piece without drawing a grid on the interfacing and having that extra step.
The tear away stabilizer method has some real possibilities as it can be torn away and would not be left in the quilt. When fusible interfacing remains in the project it would affect the softness and drape of the quilt.