Details for Economy - Do’s and Don’ts
Fig. 8. Projecting portions of sections, in general, should no exceed their thickness. A 7 to 9 degree draft is usually needed to separate the production pieces from the mould and may be provided my the manufacturer even where 90 degrees is shown on the drawings.
The intersection of the unexposed or back side with the formed sides should not come to a feather edge in the mould. This can be avoided by using a shoulder as shown in Fig. 9.
The preferred section shown in Fig. 10 can be efficiently produced from a one-piece face pattern. The alternative section must be drawn across a multi-piece pattern after each casting due to no mould draft, resulting in higher costs and compromised quality.
Use standard building stone anchors whenever possible. Where relieving angles cannot be positioned to carry the load, threaded or adjustable inserts can be employed (Fig. 11).
Allow enough space in the masonry wythe to make curved pieces straight on the back. This need no apply to copings and similar sections where the major unexposed side is flat at the masonry bed joint.