IMM 2/99

I am wondering if anyone has information on a tool/apparatus that separates molds at the parting line (either an In-house design or bought from a vendor). We currently use pry bars and pipe clamps to separate the mold halves. The tool would have to be able to accommodate molds that weigh 2000 to 3000 lbs and be somewhat adjustable. I have looked on the internet but have been unsuccessful. We need to separate the mold for maintenance and to change name plate inserts If anyone can help, it would be greatly appreciated.

By far, the fastest, best, and safest method is an overhead crane and a scissor that will pick up and balance the mold. Then, if the guide pins and bushings are aligned, it will open without much pounding. The way you are doing it now, mold on its side, is the slowest way. If your table is not flat and not harder than the mold base, it will dig in and increase your stress level. They sell scissors at any good overhead crane supplier, and you can use them to pick up many things, not just molds. Make it easy, and good luck.
-R. McDonald, Model Mold & Machine Co. Inc., Indianapolis, IN, (317) 926-1505.

Our shop works on sheet metal stamping dies along with plastic injection molds. We have a hydraulic parallel lifting device that is used to separate sheet metal die halves. The unit has four hydraulic cylinders that operate dependently with each other. These cylinders are placed between the die halves at each of the four corners. The hydraulic unit then pushes the die halves apart evenly, regardless of any uneven weight distribution that may exist. We have considered adapting the plastics molds with external lifting points that would facilitate the use of the die separator. The actual unit is called a Hyla-lift from Hylatechnik. This can be purchased from IC Fluid Power Inc. in Perrysburg, OH. The phone number is (419) 872-9609.
-M. Nelson, Maytag, Newton, IA, (515) 787-5214.

Here is a method I've used with great success on a 2700 lb. 24-by-30-inch tray mold. When preparing to tear down a run, leave the press clamp open and lift out each half separately. There is less risk of damage than when using pry bars to split the mold out-of-press. A good set-up person can rehang the halves independently in less time than you'd think. Knockout bars go in first, then the A half, using the locating ring to align it for bolt up. The B half must be guided in to the A half using the pins and bushings and nudged ever so gently in to full closure with the machine's clamp. Depending on the mold, pry bars might be required to make adjustments as you go but never at the parting line. This really works!
-W. Ovre, W.I. Ovre and Sons, Morton, MN, (507) 697-6121.

The Bermer Built Lift Tong provides a straight vertical movement when used with a mechanical lifting mechanism such as a crane. It is used to simulate mold openings, prevent bodily injury, and eliminate costly mold damage. The device utilizes the clamping slots of standard mold bases. They are manufactured in three standard sizes: 17 inches, 1100-lb limit; 24 inches, 3300-lb limit; and 30 inches, 4400-lb limit. The size represents the maximum mold width the lift tong is designed to handle. Bermer Tool and Die has been manufacturing this lift tong for 30 years. We experienced the same problem as the reader. This product was designed after a very expensive optical mold was damaged while assembling the two halves for shipment
-P. Grudzien, Bermer Tool and Die Inc., Southbridge, MA, (508) 764-2521.