As for the first article, we’ve tackled the usual problems of Punch and Dies. Now, we’re going to give you tips for the proper maintenance of your punch and die to help you avoid these kinds of problems.
If you’re daily routine includes these kinds of task namely fixing broken pads, welding damaged die section after the dowel falls out of the upper half and replacing pilots that have pierce holes in a progressive die, you’re doing some die repair.
The common cause of die problems are poor die design, improper setup procedure and maintenance and lastly the tool design. Through proper maintenance like cleaning the die, inspecting for loose dowels and lubricating the components, you can be sure that your tool can last longer than usual. Preventive maintenance should be addressed regularly to reach the optimum capability of your punch and die.
Sharpening your Punch and Die
When the punch is making too much noise than you think it should, the best conclusion to that is your die isn’t sharp enough to punch the material. Here are some guidelines when sharpening cutting sections, buttons and pierce punches.
Grind the proper cutting shear
- Angular ground on the cutting section helps to reduce the cutting force and helps the die to quiet down. Proper cutting shear reduces the shock loading of the die and press, it prolongs the life of the press and the die.
Using the Right Grinding Wheel
- If you’re grind tool steel sections such as D2, M4 and powered metal, you’re actually grinding small carbide pools. Carbide is a very hard metal to cut and when cutting carbide, use a wheel that breaks down and does not load up in the process of grinding. Heat is also a problem when grinding in the die section that causes softening and cracking of the die section or punch. To avoid this kind of problem, use a flood coolant method that will help your die section as cool as possible.
Punch and Dies usually overheats from time to time. If you’re experiencing this kind of problem, make sure to follow these tips to avoid overheating.
- Lubricant are used to decrease the friction that builds up heat. Make sure to put some on your tools and if lubricant isn’t a choice or slug pulling occurs:
- Use more than one punch at the same time with the same size in the sequence of your work. By rotating the punch, there will be a longer time for the punch to cool down before it can be used again.
- The best way is to take some time for the tool to rest. Stop the press for a while from time to time or alternate the punches in doing the work to avoid overheating.
Cleaning and Inspection
Cleaning and inspection of your punch and die should be one of your regular routine to avoid punch and die problems. Here are some tips for you on how you should do it.
Look for Galled Die Section
Inspect the tool for wear plates and Cam surfaces.
Regrind and Fit as necessary
Inspect the die to make sure all the safety guards are in place. Also, lubricate all necessary mating die surfaces.
Clean the debris such as slug, silver and lubricant build up from the dies. After cleaning, make sure to dry the die to make sure it will not rust.
Look for dull or cracked, chipped and dulled die section and replace as needed
Make sure that cutting punches are secure in their retainers
Look for loose Fastener
Check all screws and make sure they are tight enough. Don’t forget to look for missing dowel pins in your tools.
Determine or look for the problem why did the spring broke. If the springs are close to being destroyed, replace immediately to avoid unnecessary problems with your punch and die.