Selecting and using the best abrasive for each metalworking application is not difficult, but understanding what to use and how to use it to maximize productivity in your metalworking shop requires some research.GRASSLAND Abrasives Cutting wheel.
Selecting the right abrasive and using it correctly in metal fabrication applications and welding can play an important role in maximizing productivity and reducing costs.Still, in today’s tight deadlines, manufacturers tend to use whatever abrasive is convenient, regardless of which abrasive is best for the application.Some may even ignore some basic rules of grinding safety.The result can be reduced finished product performance, increased grinding and finishing costs, and reduced productivity.
It is important to realize that abrasive products come in various grades and some manufacturers designate them as good, better and best (this is the scheme used in the table in this article, in descending order: 1=best, 2=better , 3 = good).
Metal fabricators who measure total grinding results and want to achieve the lowest total cost in their application use the best abrasive products for most of their work, while using mid-grade products for high productivity applications where only abrasive cost is important.End users who want the lowest initial cost may opt for a premium abrasive, but should be aware that such an option may not be economical in the long run.
Fabrication and welding shop owners interested in determining total grinding results can work with their abrasive suppliers to test and compare various grades of abrasive and alternative products from different manufacturers.This on-site testing can reveal relative abrasive costs based on price and wear rate, and can even measure overall worker productivity based on worker wages.The relative abrasive cost can then be added to the operator cost to determine the total grinding cost.Such tests often show that the most advanced (and best) abrasive products generally last longer, work faster, make the most of workers’ time, and generally offer the most cost-effective option.
The first step in processing a weld is grinding to remove it as much as possible .The amount of work required for this step depends on the hardness of the material, the type of weld, the skill of the welder, and several other factors.In most cases, using an angle grinder is the most economical way to remove weld beads.For this application, the abrasives used on these tools can be fiber discs, flap discs, or smaller versions of these products for better control or handling of smaller work envelopes.
Fiber discs remove excess material from flat and contoured surfaces with a fast initial removal rate.Some hints:
Flap discs are suitable for removing heavy welds and excess material while providing a long service life:
Whether using flaps or fiber discs, high-performance ceramic grain abrasives work best when powered by angle grinders rated at over 1,200 watts.
The second step is to remove the scratches created in the first step and set the directional scratch pattern of the final product.During the disassembly step, it is important to be below the rotating scratch pattern produced by the grinder.If this pattern is not completely removed, deeper wear marks may appear when trying to develop a finer finish.The abrasive that reaches this stage, a No. 3 polish, is a regular 100 or 120 grit belt of the desired size for the part
For applications requiring a size 4 to 8 finish, scratch depth, pattern and direction are generally uniform across the product surface.To achieve such a finish, it is common practice to use an abrasive with the same linear scratch pattern as the one used in the previous step, starting with a medium-grit non-woven tape or wheel.
When the final product does not require a uniform directional scratch pattern, a rotary tool can do the job after soldering.In this case, the two abrasives of choice are premium nonwoven uniform grinding wheels or nonwoven surface dressing discs.Surface mixing discs conform to contours and provide lower stock removal rates and finer finishing capabilities.
Controlling the use of the disc at a 10 to 15 degree angle prevents random scratch patterns.Coarse grade discs provide mixing capability to prepare the surface for coatings such as polishing or paint.
It may be advantageous to switch to a nonwoven product as soon as possible during the mixing process.For example, deburring, blending and trimming can be done with one nonwoven product to reduce the number of discrete steps.Nonwoven products also provide a controlled, continuous finish while reducing the potential for undercutting and gouging.Nonwoven product types also provide a cooling effect to minimize the chance of warping or discoloration.Finally, it runs quieter with less vibration.
Post time: May-17-2022