Fibral non-woven abrasive material can be converted into endless belts. The bulk and openness of the fibral backing requires additional adhesive, additional drying time, lower pressure and lower press temperatures than standard coated abrasive belt making techniques.

Backing Preparation

• Cut belts to desired angle - Recommend 55°, 67°, or 80° bias angle.

• Abrade nap from non-abrasive side - Recommend 80 grit abrasive belt or flap wheel.

Suggested Adhesive Formulation

Note: Typically, the adhesive has 20% solids.

	ADHESIVE FORMULATION	WEIGHT	VOLUME
Resin:	Sheldahl A0455 or A0651	100 parts by weight at 20% solids	100 volumes
Curing:	Desmodur® RE or RFE	11 to 15 parts by weight	8-10 volumes

Suggested Adhesive Preparation for Backer and Tape Coating

Generously apply primer to scuffed area of backer and edge of butt. NOTE: It may be possible to spray the backing with multipass but it will require some dilution and experimentatioin by the fabricator.

Coating the Tape

When using a brush or roller, apply a liberal amount.

When using a tape coater, the following coating gaps are recommended for Sheldahl splicing tapes.

T1880, T1882	0.012" to 0.016" plus tape thickness
T1886, T1878	0.022" to 0.026" plus tape thickness

Allow adhesive on backer and tape to dry approximately 30 minutes.

Pressing

Press pad plastic panel or webbing are required on the grit side.

Place pre-tacked belt in bonding press with a release sheet/pad configuration to prevent bonding to the heated bars.

Suggested Press Cycle

Time:	7 to 12 seconds
Temperature:	From room temperature to 150°F (65.6°C)
Pressure:	Low pressure required. Recommend 1000 to 2000 psi

Adhesive Sources

Sheldahl A0455/A0651 Sheldahl Technical Materials 1150 Sheldahl Road Northfield, MN 55057 507/663-8000

Desmodur® RE or RFE Manufactured by BAYER Available Worldwide

Tape Source

Sheldahl Technical Materials

Trouble Shooting

Excessive Hinging

• Fabricator may want to consider some process to fill the gap in the belt ends with adhesive.
• Use stiffer tape, i.e., T1886.
• Wider tape can inhibit hinging and adds shear strength.

Splice Distortion

• Excessive temperature, pressure or retained solvent will curl or distort the splice area.

The above recommendations are based on preliminary evaluation of a coarse grit product. As more information and products become available, Sheldahl will update its suggestions.

Product data is for informatioin only and may vary dependent on individual products and processes. Sheldahl does not guarantee, nor will it accept obligation or liability based on the use of this data. All data subject to change without notice.

Top