Custom Trimming Machine

The client manufactures rubber products for a variety of different markets. The products are dip moulded and during processing require trimming to form a continuous nick free edge for future processing. This trimming was previously being carried out as a manual operation requiring skill and time. As customer demand for the rubber products increased it was proving difficult to meet demand and to control cost.

The client asked HPDL to design and build a custom machine that could accurately and repeatedly trim a variety of different dip moulded rubber product sizes and types. HPDL prepared a dimensional audit of each rubber product and used this to inform the design of mandrels on which each product would be placed for trimming. The sizing of the mandrels was proved by preparing 3D printed parts which were spun in a lathe to determine optimum speed and stretch factors. Based on this data HPDL devised a concept design for the trimming machine in 3D CAD and reviewed it with the client. 

The finished design is an automated cutting machine utilising two separate drive mechanisms, one for controlling the path of the cutters and another for controlling the rotation of the mandrels. The two drive mechanisms are controlled and operated by a custom-built control module.

With the overall design agreed, HPDL investigated the practicalities of cutting the rubber products by building and testing a number of different cutter blade assemblies. This included testing to evaluate cutter wear and blade bearing wear. This process required specialist material hardening and grinding commissioned out of house to achieve extremely hard wearing and durable parts.

HPDL built the trimming machine and tested the machines capabilities with a proving trial that informed improvements for safety and usability. This exercise allowed us to refine the operating and maintenance instructions and instruct the software engineer in how to set up the control module and integrate the safety interlocks. 

HPDL produced a detailed SOP (Standard Operating Procedure) document for the trimming machine and handed over the machine in person as well as giving a training course. 

The end result is a custom trimming machine that delivers a speedy, cost effective, precise and safe cutting solution.