How To Avoid Frame Adhesive Failure
Question
My fabric is not sticking to my frame. I am using a cyanoacrylate product on a 380 PW 34 fabric. What am I doing wrong?
Solution
Unfortunately, there is no one answer to your question. Several things can cause your adhesive to fail, whether you are using a cyanoacrylate, urethane or other type of adhesive. The following are some preventive measures you can take to avoid adhesive failure.
1. You must make sure the frame-gluing surface is not too smooth. (If you notice, new frames are sandblasted or roughened mechanically with a grider; this is done to improve adhesion.) Sometimes a rough (80 grit) sandpaper is needed to give the frame some "tooth" or area that the adhesive can grab.
2. On the other hand, your frames should be clean of old fabric, ink, oils, and excessive adhesive residue. Intimate adhesive contact to the frame is critical, especially under high tension. Adhesive-to-adhesive bonds are not as strong as adhesive-to-metal or adhesive-to-wood bonds. Frames can be cleaned (prior to applying new adhesive) with a debonder solvent, or a solvent like acetone to remove adhesive, inks, dirt, and oils.
3. It is also very important that you select the right adhesive viscosity for each particular mesh count. In your case, on a 380 PW 34, an adhesive with a low-viscosity of 100 centipoise would be recommended. A good rule of thumb is:
Trade grades of adhesive are also available that are 600 centipoise for use on mesh counts from 110 to 355. Some adhesive viscosities are denoted by LV (low viscosity) and HV (high viscosity). Proper selection will ensure that the adhesive will flow through the fabric and provide a good bond by bridging the gap between the fabric and the frame.
4. When using two-part adhesives that need to be mixed, (versus cyanoacrylate adhesives that do not), it is important to follow the manufacturer's recommendation for the proper mixing ratio. Failure to do so can cause problems with curing times and/or solvent resistance.
5. When you activate a cyanoacrylate adhesive with either the pump or aerosol type activator (this speeds drying time), keep in mind that it only takes a light misting to start the curing process. If you spray too much activator on the adhesive, you can cause the adhesive to turn white or "bloom." This can affect the adhesive's strength.
6. Likewise, beware of the old adage, "If a little is good, a lot is better," when it comes to applying the adhesive. You only need a thin coating of adhesive to adhere the fabric to the frame. If the adhesive layer is too thick, the activator may only cure the top portion, while the portion that is in contact with the frame is still wet and may not cure for a few more minutes. If you feel you need a thick layer of adhesive for solvent resistance, add a second layer after the first layer is fully cured.
7. Check to make sure your frames are not warped, and that the face of the frames are completely level. If your frame does not lie flat, this may cause the fabric to remain raised off affected areas of the frame surface after you pass these spots with the adhesive applicator. A quick remedy for this would be to add weights on the inside and/or outside of the frame during gluing to bring the fabric into intimate contact with the frame. A one-inch steel bar stock can be used for this purpose.
| Mesh Count | Recommended Adhesive Viscosity |
|---|---|
| 255 and up | 100 Centipoise |
| 255 and under | 1500 Centipoise |
| 110 to 355 | 300-600 Centipoise |