Basic Information about Stretch
- Stretch in the width direction is greater and easier to manipulate than stretch in the length.
- Stretch is not uniform with all colors and is greater with lighter colors than with darker ones with less dye penetration.
Grain and Nap
- Please consider the direction of the design when cutting patterns, such as with NYTEK® Products like MOCCASIN, BABY OSTRICH, CANE, etc.,
- The nap of NOVASUEDE® is a non-directional design.
- Trim excess selvages to prevent them from showing through the cover or creating bunching or wrinkling.
- Add notches to eliminate gathering of selvages under the cover.
Wrinkle Removal and Moisture
- Remove wrinkles by pulling the excess cover taut in all directions. Mist steam or water on the back of the cover to assist in this process.
- If excessive wrinkles are present, check for correct pattern size, accurate orientation of the patterns in relationship to the stretch of the goods, proper fillers and a correctly sewn cover.
- Use foam to provide enough support to keep the cover filled for a tight look.
Bagging Prevention: Moisture and Humidity
- Moisture will absorb into the micro-fiber matrix of NYTEK® products, especially NOVASUEDE®, resulting in expansion and greater elasticity similar to natural leather.
- To prevent bagging, the cover needs to be exposed to an adequate amount of humidity, the cutting patterns should be properly sized and the cover needs to be pulled tight. Be sure to use adequate and appropriate cushion filling materials.
- NYTEK® products should be exposed to humidity before and after being cut to allow for expansion as their micro-fibers absorb water. If the shop is not climatically controlled to regulate humidity, steam the cover well both during pattern development and upholstering. Correctly fitting the patterns and placing the cover properly in an expanded state will negate the effects of humidity in the future. All excess bagging or stretch should be eliminated at this time.
Why Bagging Occurs After Upholstering
- The covers were sewn and/or applied loosely in low humidity conditions. Bagging occurs after the cover sets for a few days and the temperature and humidity have increased dramatically.
- Bagging also can occur if the cushion breaks down. NYTEK®, like leather, is not totally elastic. It should be properly supported to prevent puddling. Puddling is a special type of bagging or sagging that occurs on the chair seat. It is a mark remaining after the sitter rises, but the chair’s foam does not recover. The material on the chair now looks too big because the cover is not properly supported, e.g., like a director’s chair. The upholsterer needs to properly support the cover the material with foam or springs to prevent this.
- The backside of NYTEK® products tend to grab or cling to foam.
- Apply a thin layer of spun polyester fiber batting over the foam to reduce drag.
- Spray slickeners can be used to reduce drag and are available through most upholstery supply houses. Avoid slickeners containing silicone that can disburse small particles into finishing areas. Some shops are reporting success using talcum powder on exposed foam surfaces. Steaming or misting water onto the back of the cover also may help. Excess wrinkles should be pulled out while the cover is expanded.
- Majilite can add a backer to NYTEK® products to provide a slicker surface during the manufacturing process. Contact Majilite for feasibility and pricing.
- Specify appropriate cushion filling materials.
- The back of the cover tends to cling to foam so placing something between the cover and the foam will reduce this problem.
- If the cover creeps on the cushion during sitting, it will resist returning to the proper position if it is restricted from sliding freely. Add a layer of spun polyester fiber batting to remedy this problem.
- Avoid bonded polyester batting, which sets at low temperatures and doesn’t spring back quickly, and shows unattractively through the covers.
- Foam quality also is a factor in the performance of the cushion; 3 lb/ft3 HR foams achieve the best results. 1.8 lb/ft3 foams are frequently used as a cost-saving measure but they must be able to fill out the cover and retain the shape of the cushion.
- There are a number of products designed to be used as cushion fillers. As with natural leather, any bunching or wrinkling of materials under the cover may telegraph through and be visible on the surface. NYTEK® products also can be backed with a variety of materials.
- Vent cushions for proper functioning.
- Air exchange should occur quickly and freely when the cushion is used so air does not become trapped, which prevents the cushion from functioning properly. A poorly vented pillow will seem hard when it is first sat on and will usually be noisy as it expends the trapped air. After someone leaves the seat, a poorly vented cushion will appear deflated and take time to recover.
- Include air evacuation holes or panels when constructing cushions or pillows to allow for the free movement of air caused by the compression and expansion of foam.
- Add a complimenting breathable fabric in the zipper boxing for double-faced cushions. Many manufacturers only face one side of the cushion and use a complimenting fabric for the bottom and back, which should negate any airflow problems.
- Loose pillows have a tendency to slide. NYTEK® products like FINESSE® have a smooth finish that will slide freely against itself or a similar surface.
- Using a complimenting cover that has more grip or friction on the underside of the cushion and/or the deck of the seat should restrict this. Cushion ties are frequently used on loose pillow seat construction. Other NYTEK® products like NOVASUEDE® are naturally resistant to sliding. Someone slipping out of the seat is symptomatic of underlying problems with the cushion construction and/or the relationship of the pitch between the seat and back.
Staple Cutting of Material
- This can occur if the plunger extends beyond the tip of the staple gun when it is discharged during a tight pull or bridged cover.
- Try eliminating any bridging of the cover and regulate the air down on the gun. The staple plungers on the staple guns also can be trimmed shorter so they are flush or just shorter than the nose of the gun.
Regulating With Heat or Steam
- Carefully make adjustments with heat or steam after upholstering. Spun polyester fiber batting used in cushion padding will melt easily if exposed to heat. Adhesives used in prepping may also release under heat.
- High temperature heat guns should be used carefully and sparingly to shrink small wrinkles out of the cover. Experiment with pieces of scrap first. Steam may be most effective when applied to the backside of the cover to give it more stretch prior to application, making it easier to pull tightly.
- Holes and cuts cannot be repaired. To avoid future problems, use experienced operators to work on complex designs.
- Re-upholstering involves the same skills as general upholstering and the same cautionary measures should be followed.
- Expedient short cuts will produce unsatisfactory results. This can include trying to upholster over existing covers, not refurbishing or replacing worn or broken down padding or fillers, not carefully inspecting the job for foreign materials, not removing old tacks or staples, and not repairing substrate materials.
- Back vertical panels with Majilite’s lightweight polycotton sheeting backer or foam/tricot backer. They help provide stability and prevent sagging in humid conditions. Stapled covers should be pulled down as tightly as possible. Steaming the cover first is recommended.
- If the operator wants to glue the cover to the panel, please refer to the section on DIRECT LAMINATION and/or the section on PANELS AND WALLCOVERING that appears later in this guide.
- Expose cushions to humidity to prevent bagging.
- Apply slickeners and a thin layer of spun polyester fiber to prevent drag.
- Use proven techniques in cushion construction.
- Include air evacuation holes or panels when constructing cushions or pillows.