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Specifications

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Anvil Set

This sturdy machine is cast in a good old-fashioned foundry in Stoke-on-Trent, which is one of only a few capable of the required substantial sustained pour from the crucible in order to produce the stiff ribbed frame needed with a 600mm deep throat for these machines. Featuring a useful working throat depth of 24 inches (610mm), it has a large 7.8 inch (200mm) diameter top anvil cut from a huge chunk of EN16 machine steel, it’s 2.75 inch (70mm) wide face is scalloped out on each face to reduce inertia, and aid hand movement, for those tight corners. Five lower anvils are supplied 2.75 inch (70mm) with the machine. All are precision CNC cut from machine steel, from an almost flat, to a very tight curve, and come with a tray for easy access to the desired profile.
These are;
· R400 (15.7”) with a contact area or blow width of 12.0mm
· R300 (11.8”) with blow width of 8.5mm
· R200 (7.8”) with blow width of 7.2mm
· R100 (3.9”) with blow width of 6.35mm
· R50 (1.9”) with blow width of 4.0mm
This machine features a unique adjustable anvil cradle, allowing perfect alignment of the contact patch or blow, reducing panel marks, allowing good stretch overlaps, while reducing the need for any further planishing.

how to use it

The design is simple, with few moving parts. The most significant part of the machine is the frame usually made of cast iron. The Frame is "C" shaped and the gap from the anvils to the rear of the C is called the throat, The design objective is for this structure be very stable, sturdy and extremely rigid.

The parts used to do the shaping are fixed at the open end of the frame. A flat-faced, hard steel wheel, or its other name “anvil” is fitted at the top of the frame. This is mounted on an axle with strong roller bearings.

The lower rollers, often called anvils, also have axles and roller bearings. These are smaller in diameter than those of the top wheel. They have a curved surface, each of them different in its profile to suit the requirements of the panel to be manufactured. The anvils are mounted in a strong steel yoke which is moved vertically by turning a large steel hand-wheel located at the bottom of the machine, or in some cases the use of a foot-wheel allowing the operator better support of the panel whilst he or she is working the panel.

This control wheel is attached via a coarse screw thread. The yoke or cradle sits on top of this screw and moves up and down with it as it is turned.

It takes several different passes of the panel between the upper and lower anvils to achieve a high crowned curve in a metal panel.

To produce the required curve in the panel the operator uses slight pressure on the metal as it passes between the anvils; just enough so the metal doesn’t skip or slip through the wheels. Too much pressure will produce marks in the surface of the work and spoil the panel.

The first few passes of the metal panel through the wheel will indicate if the pressure setting is correct and, more importantly, if the anvils are aligned. These anvils have what is commonly known as contacts, lands, or blows; this is an area on the anvil that is slightly flattened out to reduce marks in the stretching process.

To begin, the operator inserts the metal panel into the wheel and adjusts the yoke to achieve the correct tension as described above. Then the operator moves the metal panel through the wheel in a gentle, smooth, back-and-forth motion. As it is passed through the wheel the panel takes its compound shape.

How the metal is moved through the wheel is very important. Each pass of the metal through the wheel must be close enough to the previous one so they will overlap slightly; this is known as tracking. This effect can be seen on the reverse of the panel, where the contact or patch area of the anvil in use is clearly seen in lines. If the passes do not overlap on each pass the metal will stretch unevenly, and the surface will be irregular leading to extra work to get the required standard of finish.

The panel must also be moved from the operators right-to-left, (or left-to-right) without missing any section of metal and each track must be parallel to the previous one. The wheels press the metal in a long line, and the aim is to move evenly so all of the metal is stretched evenly. To learn to “track” correctly takes time and patience, and when first staring out it feels akin to riding a bicycle backwards.

If a panel requires more shape on one side than the other, the number of wheeling passes determines the degree to which the material stretches and therefore the amount it curves. The process of wheeling, gradually reduces the panel thickness on each pass so there is a finite amount of curve that can be achieved whilst maintaining an acceptable thickness of the material being worked.