FIRST SEMESTER - THE PROCESS MACHINE TYPES
Fourslide, Multi-side, Rotary Slide, Linear slide. These are all terms thrown about to describe a type metal fabricating machine that processes metal in the form of wire or strip. But no matter what name you hear, all these machines have one thing in common. They use cam driven slides to punch and bend metal. Each of these types of machines has strengths and weaknesses. It is probably the weakness of one machine that spurred the development of another. First let’s start with the basic layout of a fourslide or multi-slide? A fourslide or multi-slide has four basic machine sections. They are the Straightening, Feed, Press, and Forming sections. No matter which of the different types you look at you will find these machine sections. Our explanation of the sections will be based on the layout of the horizontal fourslide or multi-slide machine. These machines have four shafts around their periphery connected by miter gears that transmit the necessary motion to the various machine components.
STRAIGHTENING SECTION
Material for a fourslide or multi-slides whether strip or wire is packaged in coils.
The straightening section of the machine is where the raw material enters the machine and is pulled through a set of rollers to remove the coil set from the wire or strip that is being processed. Removing the coil set is critical to producing a consistent part.
FEED
The feed section moves the raw material through the fourslide or multi-slide. It pulls the material through the rollers and pushes it into the press and forming sections. Although the feed components of all manufacturers are slightly different they all work on the same principle of a cam actuated grip. The feed body rides ride back and forth on a slide. On the forward stroke the material is gripped and pushed forward into the press and forming areas. On the return stroke the grip is released and the body moves back to begin the cycle again.
PRESS
Next the material enters the press section of the machine where the initial work is done. The press section operates in a manner similar to a conventional punch press and performs most standard press operations. The big difference is that in the case of a horizontal bed machine the press runs in a horizontal direction instead of a vertical. The press area is where most of the notching, piercing, coining, shearing is done. Die construction for slide forming is very similar to that of dies for punch presses. The main difference and a disadvantage to horizontal press machines is that the die slugs do not fall out of the die due to gravity as they do in a vertical stroke press. The die designer must come up with ways to control the exit of the slug from the die. Some of these include blowing the slugs out with air, sucking them out with a vacuum and gripping them and then pushing them out
FORMING SECTION
Finally the material enters the forming section that is made up of a cutoff unit, forming slides and the king post sometimes called the head. The cutoff unit is located between the press section and the front forming slide. It cuts or separates the blank from the strip at the completion of each feed stroke. The material ends can be cut off straight or shaped. In the case where the end is shaped scrap is produced. We’ll discuss various cutoff end designs a little later. While the blank is being cut, separated from the strip, it is held by the front tool against the center tool in the forming section.

cut off unit

FORMING SECTION CONTINUED
The forming section is where 4 or more cam driven slides, riding in channels cut into the bed of the machine, bend the blank into the final form

Each slide is advanced by a cam mounted on a camshaft. The cam is individually timed to strike and form the blank around the center form or center tool, which is held in the kingpost. The most common motion for a slide is to advance, dwell, and retract. Using a cam with multiple lobes the designer can advance and retract the slide a number of times during one forming cycle. The tooling is mounted to a tool holder that is then mounted to the slide.

FORMING SECTION CONTINUED
To give the machine more versatility, in addition to the horizontal motions, there are two vertical motions called the form lifter and stripper. The form lifter can perform bending in the vertical plan or it can be used to move the center tool up or down for two level forming. The second vertical motion is the stripper and this is used to positively eject the part from the center tool.
Next let’s look at an advanced tooling sequence which will give you an idea of what a fourslide, multi-slide is capable of.
Now that you have the general concept of a how a fourslide, multi-slide works let’s take a look at the major types I mentioned earlier. All these different type of machines fall into a category call slide forming.

FOURSLIDE – originally this term was used to identify a machine that used slide forming technology to bend wire or strip but did not have a press section. In the 40’s the main producers of fourslide equipment came out with machine designs that did have press sections and at that time the term 4-Slide became a generic term for horizontal slide forming machines with four slides. Today a fourslide typically refers to the machines manufactured by the Nilson Company now owned by US Baird. The Nilson fourslide is a horizontal bed machine with four slides arranged in a 90° pattern. The main advantage of this design is an open forming area. Disadvantages include; the size of the press section is fixed, the die can only punch from front to back and the machine has a closed, restricted bed space. There is also a vertical model that takes up less floor space and solves the problem of ejecting slugs from the die.
MULTI-SLIDE – this term is a trademarked name of the US Baird Company’s design. It is a horizontal bed machine with 4 slides in a 90° pattern. Advantages are that it has an open press area that will accommodate longer dies or multiple dies, the dies can be setup to punch from front to back or back to front (this allows one to orient the burr), the open bed also gives the user space for adding a tapping unit. Disadvantage is the limited space in the forming area.
ROTARTY SLIDE MACHINE – manufactured by European and Asian companies it is a vertical machine that can have as many as 10 forming slides. The slides fit into slots located along the radius of a large ring gear built into the bed of the machine. Advantage is that it allows the designer to position the slides to strike the part at the optimum angle, simplifying the tooling. Disadvantages are the machine’s limited die capacity and tool setup can be complex and lengthy.
LINEAR SLIDE MACHINE – This is also a vertical machine that has several opposing slides arranged in a linear pattern. This is a very versatile machine and what it lacks in press area can be made up by using the opposing slides. These types of machines are typically dedicated machines due to the complex setups. Each type of machines has its advantages and disadvantages and it is the part design and the ingenuity of the tool designer that determines which is the best fit. Not sure which is right for your stamping or wire form? Contact the engineers at wm dudek mfg and they can help.