Shaved V Ground Edge Cutting Rule

Ground edge
Shaved edge

What do we mean by shaved and ground edge cutting rule?

The terms shaved and ground edge when applied to cutting rule relate only to the way in which the cutting rule is manufactured. In the article, we look at the difference between that process and determine which is best to use during your production run.

Shaved Edge

What is Shaved Edge Rule?

For Shaved Rule, the method of production uses a series of hardened solid tool tips to shave away the excess steel in order to create the cutting profile. After shaving the edge profile, you are left with a precision smooth HQ surface on the bevel of the rule. The finished shaved product is very sharp and most suited to the accurate Die cutting of paperboard products.

The shaving process is a much faster operation than grinding the profile on to the blade, which is a slower additional process.  

What are the benefits of Shaved Edged Rule?

Rules can be manufactured in a range of body and tip hardness’s depending on the substrate being Diecut. Typically, shaved rules aided by a decarburised layer in the blade can achieve a slightly tighter radius bend without cracking at the tip of the cutting blade. This  lends itself to the manufacture of Boxes and cards

Options for shaved blades will be through hardened or Tip hardened product, Centre Bevel (CF), Long Bevel (CFDB) and Side Bevel blades (SFDB) Differing bevel angles, from Standard 53° bevel or 42° bevel which enables  lower pressure cutting on auto platen machines.

When should Shaved Edges Rule be used?

Shaved rules are usually used to cut Corrugated boards, Folding Box Board (FBB) etc            The majority of supermarket food packaging, pharmaceutical cartons, Greetings Cards and Point of Display stands will have been produced using rules that have been manufactured using the shaved rule process. To make tough (recycled) substrates less susceptible to dusting Bohler can apply coatings to the blade, these will aid friction free cutting and certain coatings will enhance the life of a blade.

Ground  Edge

What is Ground Edge Rule?

A Ground edge rule must also go through the same process of edge shaving, but it then undergoes a secondary process of a series of precision grinding wheels, which grind vertically to finish off the sides of the profile edge.

What are the benefits of Ground Edged Rule?

The results of this process are to leave the cutting tip with a microscopic saw like finish which is extremely sharp, sharper than a shaved edge blade and suitable for cutting plastic type materials.

Rules can be manufactured in a range of body and tip hardness’s depending on the substrate being Diecut, and because of the blades sharp qualities a ground rule is a given when cutting plastic type substrates.

When should Ground Edges Rule be used?

Typically PET (Polyethylene terephthalate) and recycled PET (RPET) are easily cut with a ground edge rule. There are no discernible visual differences between RPET and Virgin PET material, clarity of product is excellent with both substrates safe for direct food contact.     So you will typically see Thermoformed (vacuum formed) products like Clam packs and blister cards manufactured using Ground edge rule Technology in the dies. A packaging manufacturer may also use Ground Edge blades when cutting Laminated or foil board (metallic polymer) packaging.

Several options are available for these blades. Tip hardened product Centre Bevel (CF), Long Bevel (CFDB) and Side Bevel blades (SFDB). Body and tip hardness would generally be higher to give good stability and longevity when cutting tougher substrates. Other applications would be cutting Rubber, plastics, Gaskets materials and some laminated substrates.

Bohler have a range of Shaved and Ground Die Cutting Rule products available in their latest catalogue. For more information on the bohler range of Ground & Shaved rule, please contact the sales office on 01254 671875.

7th November 2017, 17:01