Finishing FAQs

What type of finish is best for metal?

There is a general description of each designated finish values (0 through 8). These descriptions can be found in the chart to the left. These descriptions will vary throughout the industry. There is no specific value to any of these numbers. The most accurate way to quantify the finish you require is to target a measurable surface roughness.

How is surface roughness measured?

Surface roughness can be measured in both standard (µin) and metric units (µm). The most common tool used to measure the surface roughness of a part is a profilometer. 99% of the time, an Ra measurement is all that is required; in more specialized applications, other measurement types are available (see table on right). A profilometer measures the topography of the surface of a part by dragging a stylus perpendicular to the scratch direction. The resulting measurement value is the measured surface roughness of the sampled area.

Wet and dry machines both process the material in the same way; but wet machines add a coolant that is sprayed onto a part as it is processed. 

Dry Machines are often the preferred choice because they are generally less expensive to purchase and often have a longer life.  Relative to wet machines, there is a much greater risk of fire. Also, unwanted warping due to heat friction, and multiple footprints can result. 

Note: WE HAVE SEEN MANY BUILDINGS GO UP IN FLAMES FROM NOT CHOOSING WET GRINDERS FOR THEIR BUSINESS.

Wet Machines include a filter unit that also pumps coolant on the part, and usually include a drying unit that removes the coolant from the part as it exits the machine. Difference includes one footprint, longer belt life and a finer finish than with dry machines. Although sometimes bits of metal dust and water can collect and turn into a sludge that clogs the machine, as long as the grinder is cleaned every once in a while then there shouldn’t be a problem.

For information on machines, visit our Timesavers page.

What is Manual Grinding?

For small-grade applications, manual grinding of metal can be performed by using a file. However, in most metal fabrication operations grinding is executed with a grinding machine. Metal grinding with a handheld grinder or a stationary grinding machine with industrial grinding wheels or belts are two forms of grinding in metal fab. A portable grinder might be used instead of a grinding machine in hard to reach areas or when larger metal parts will not fit on a machine grinder. Learn more about our manual grinders here.

Paint Adhesion / Roughing

Generally a single head belt running a coarse abrasive.

Grained Finish

Between 1 and 4 Belt Heads (# of heads dependent on customers budget and throughput)

Brushed Finish

Mixture of 1-3 Belt Heads followed by 1 or 2 Brush Heads

Random / Non-directional

No linear lines (Disc or Rotary Brush)

Target Surface Roughness

1 to 4 heads (generally all belt heads, but may add a brush at the end depending on the customer requirements). These applications usually have a target Ra or MicroInch value.

what is the standard finishing type?

There is no standard finishing type. If you look at the table above, the descriptions that best suit the purpose of your material finish

how fine of a finish is timesavers capable of giving?

Based on the table above, Timesavers machinery is capable of finishing anywhere from a #3 to a #7 finish on most parts. A #8 finish may require the use of buffering compounds, which would be applied to the part and then buffed on another machine or by hand.

HOw long does a Timesaver Last?

It varies on how well you maintain the machine - but typically, a good lifespan for these machines fall around 10 years or so. We’ve had customers with much longer lifespans, too - and support and service is always readily available for all of our customers.

i have a plastic molding that needs to work well with an adhesive, will a timesavers machine work?

This is a seemingly uncommon question that we come across fairly often. Certain machines can rough the surface of plastic well enough to provide a good mold for adhesives. Although it’s not necessarily what Timesavers machinery is built for, it can be used in certain applications like this. Please contact us if you are doing a similar task, as our technical specialists will be better able to assist you.

can you deburr non-flat parts with a rotary brush?

Using a belt with a non-flat or rounded metal part may lead to some serious issues. If the vacuum surface at the base of the machine cannot fully grasp a part, then when the rotary brush moves over the part it will throw it and may very well damage both the part and the entire machine.

what is the best way to grind stainless steel?

If you’re looking for deburring of a next-level quality, then we’d recommend purchasing pre-polished stainless steel sheeting. That way the finished metal will have less burrs and a much smoother finish.