Beveled blades

In the rod-blade coater unit a rod is mounted at the end of the blade. This coater behaves more like the beveled blade coater than a flexible blade... 

Variable slits are used more commonly than fixed slits. There are two types available unilateral or bilateral. Both involve the use of beveled blades attached to micrometers that allow the blades to shift a specified distance, although unilateral slits have only one movable blade the other is fixed. Bilateral slits are preferred over unilateral slits because a constant center line is maintained with the former whereas that using the latter continuously changes as the slit width changes. Variable slits are more expensive but are more convenient for routine analysis. With constant use, the micrometer mechanism and blade edges become worn, resulting in a decrease in sensitivity and reproducibility. This is not considered a major problem in analytical work unless a precise knowledge of the slit widths is imperative. 

The ends of the knives can be square, beveled, or rounded. If the end is square and parallel to the web, if the upstream face is perpendicular to the web, and if there is a fixed gap between the end of the knife and the web, then the wet coverage is exacfly one-half the gap. On the other hand, if there is a low angle in a converging section of the knife or of the blade, leading up to a tight gap, as there is for many knives and for all bent blades, then strong hydrodynamic forces build up and tend to lift the knife or blade away from the web. This forces more fluid under the knife or blade, so that the coated thickness is greater than half the gap. 

Cutter blade length extends beyond the material stream width on either side of the stream and volume of the cutter is sufficient to ensure all material taken into sample can be contained in the cutter body. Cutter blades are parallel, and are beveled to a sharp edge in the case of linear-motion traverse. For rotary-motion sample cutters, sharp edges of the cutter blades are radial to the center point of rotation. 

Figure 6.2. The crystalline habit of lactose a-hydrate. (A) Prism, formed when velocity of growth is very high. (B) Prism, formed more slowly than prism A. (C) Diamond-shaped plates transition between prism and pyramid. (D) Pyramids resulting from an increase in the thickness of the diamond. (E) Tomahawk, a tall pyramid with bevel faces at the base. (F) Tomahawk, showing another face which sometimes appears. (G) The form most commonly decribed as fully developed. (H) A crystal having 13 faces. The face shown in F is not present. (I) A profile view of H with the tomahawk blade sharpened. (From van Krevald and Michaels 1965. Reprinted with permission of the Journal of Dairy Science 48(3), 259-265.)...

Bevel.—Bevels for ascertaining and forming surfaces, not at a right angle with some certain line, can be had from one dollar upward in. price. The four inch is very good size. The blade ie held in position by a screw, which forms part of the joint on which the blade turns. Shown in Fig. 3. 

Grade AA try-squares have the iimer and outer edges of the blade bevelled. All working surfaces of the blade and stock are lapped, finely ground or polished to the accuracy specified for each grade. 

The contents of the little pan are now allowed to flow into the pot, and soon after the required quantity has been crutched in, the revolving shaft is stopped, and the crutch raised out of the pot, which is then wheeled away to make room for a second pot, and is then drawm. up close to a frame, and its contents allowed to pour out by raising an iron gate situated near its base. Fig. 8 represents the crutching pot with its gate A raised by the lever B and at Fig. 7 is a drawing of the steam crutch, in which its several blades are shown. The bevel wheels above indicate its connection with the usual shafting. 

All portable, power-driven circular saws having a blade diameter greater than 2 inches shall be equipped with guards above and below the saw base plate or shoe. The upper guard shall cover the saw to the depth of the teeth, except for the minimum arc required to permit the base to be tilted for bevel cuts. The lower guard shall cover the saw to the depth of the teeth, except for the minimum arc required to allow proper retraction and contact with the work. When the tool is withdrawn from the work, the lower guard shall automatically and instantly return to the covering position. 

Although it may sound like these terms can be used interchangeably, they do have different meanings. The bevel angle is the tilt of the saw blade from vertical on the table saw, while the miter angle is the horizontal angle. Typically the maximum bevel on a miter saw is 45 degrees. 

Prepare 2.25% Bacto agar (Difco) in H O. Pour the agar into lOO-mm plastic petri dishes, approximately 7-mm thick, and cut 2.0-2.5-cm blocks with a razor blade. Cut a 45 bevel on the side on which the embryos will be aligned. This helps to view the embryos more clearly. 

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