A good quality roll slitter / rewinder is an integral part of many manufacturing processes. Roll rewinders and slitters are used to convert long rolls to shorter rolls or wide rolls to narrow rolls. It is because of these machines that we have access to products like duct tape, racing stripes, scotch tape and countless other rolled products.
If you use a roll or lathe slitter or a rewind slitter you probably already know the importance of a sharp slitter blade or knife. A dull or dirty slitter blade will produce more drag, more heat and will place an extra strain on your slitting or rewind machine. Most importantly, dull slitter blades produce poor cuts which can result in an inferior end product or in many cases a ruined roll.
It is often hard to determine if roll slitting or rewinding problems are caused from a dull blade or from other issues. Before having your blade sharpened or replaced check it to see if there are any nicks or burrs that may be affecting your cut. A nick or burr can tear the edge of the material as the blade passes each time. Since the blade will pass through the material hundreds of times during a cut the resulting problem is often disguised and difficult to diagnose.
Also, take some adhesive remover such as goo gone or goof off and apply it to the slitter knife blade and then wipe that off with a clean cloth. Adhesive build up on a blade will create excessive drag and give you poor cuts. Adhesive can also be removed by taking a razor type knife with a holder and running it along the edge of the blade while you manually turn the slitter blade. I normally spray some WD 40 or PAM on the blade before using the razor. It is sort of like removing decals from glass with a razor blade. I normally do this and then apply some adhesive remover and then wipe down.
Keeping your blade lubricated while cutting can also cut down on slitting problems. Depending on what you are slitting it is sometimes helpful to wipe the blade down with a thin coat of PAM. This keeps adhesive and other contaminants from sticking to the blade and keeps it lubricated. A misting system should do the same thing if your machine is equipped with one. We use a product called Kool Mist which is mixed with water and sprayed on the blade periodically.
Wobbly material or loosely wrapped rolls can also cause slitting problem. If the roll bounces around while spinning you can get double cuts or angel hair on the edge of the roll. The same thing can happen if the roll is loosely wound. Make sure it it tight.
If you have tried these steps and continue to get bad cuts or believe your blade is dull you can try sharpening it on your own with a hand held knife sharpener or sharpening stone or you can remove the blade from the machine and send it in for sharpening. If you do not like mailing items, keep in mind that many local machine shops will sharpen blades for you which will prevent you from having to send the blade in. Also, it is a good idea to have a duplicate or extra blade so that your machine is never down. While one blade is at the sharpening shop the other can continue working. If you are lucky enough to have an automatic blade sharpener built in to your machine then just make sure it is adjusted correctly and keep an eye on how large your blade is. As it is automatically sharpened it gets smaller over time and will need to be replaced at some point.
There are several places to get blades. If you can get them straight from your machine manufacturer that is probably the safest way to go. Other companies also sell blades and will often have you copy and fax a picture of your blade to them so they can determine the size. This way you keep the blade and save at least some shipping. They will also need to know whether your blade is a single or double bevel.
The lifespan of your blade will depend on what you are slitting with your roll slitter. Some materials have little effect on the edge and some have a drastic effect. A good replacement plan will minimize down time and will assure quality cuts everytime which is the ultimate goal of roll converting.
If you need rolls slit or converted you can go to our Roll Slitting site.
We have compiled some sources for new slitter blades and blade sharpening. Here they are :
Carolina Knife - Supplier of slitter blades. Will also sharpen blades or do custom work.
Valley Grinding - Blade Sharpening Service for all types of industrial slitter blades.
Federal Knife Company - Blade Sharpening, New Blades. Service for all types of slicer, slitter and cut off blades and knives.
Google Local Search for Machine Shops - A local machine shop can also sharpen blades. Use the search box below to find a machine shop near you. Just type in machine shop and your city and the two letter state designation. (example - machine shop Pensacola FL)
Webpages To Help You Find Other Converting Equipment
Finding Used/Rebuilt Roll Slitters - Used and Rebuilt Single Knife Log Slitters / Slicers.
Finding Used/Rebuilt Rewind / Slitters - Used and Rebuilt Rewinder / Slitters
Slitter Blades - New or Sharpened - Places to find new slitter blades or have them sharpened.
Finding Used/Rebuilt Roll Rewind Slitter Combo Machines - Used and Rebuilt Slitter Rewinders.
Some popular brands of rewind roll slitters are Smart Slitters (Genesis), Slitters International, Duesenbury/Dusenbery, Judelson/Judelshon, Lever, Kidder, Tidland, Schmutz, Cameron, Cooper, and ALS Slitters. These companies produce machines ranging from 600 pounds to several tons.