BRM Official Blog

Wolfram Manufacturing Inc. makes machined metal parts with complex geometries and fine finishes. Like other job shops, the Austin, Texas manufacturer doesn’t want to send out parts for surface finishing and deburring. When lead times are short and profit margins are tight, outsourcing this work doesn’t make good business sense. Yet many metal fabricators need to meet tight tolerances every time..     

Anodizing imparts a wear-resistant coating to cylinders. This electrochemical process permits the use of lightweight aluminum instead of heavier metals, but anodizing increases surface roughness. Moreover, anodizing increases a cylinder’s outer diameter (OD) while decreasing its inner diameter (OD). These changes in surface quality and dimensions can interfere with parts mating and sealing.     

High-nickel, iron, and cobalt alloy steels are difficult to machine.  These superalloys expose cutting tools to so much stress, strain and heat that tool edges can begin to lose their hardness. When that happens, heavy burrs won’t break off cleanly and work hardening may occur. As Metalworking World magazine explains, outsourced surface finishing may seem like the only option – but that's not the case.

Planar honing imparts a fine finish to flat surfaces like sliding guideways, machined metal parts that support linear motion. Traditionally, machine tool sliding guideways were made of hardened cast iron and fabricated with cubic boron nitride (CBN) milling tools and grinding. As Grinding & Surface Finishing magazine explains, however, there’s another way to improve sliding guideway surface finish.  

The Pontiac Firebird Trans Am was an iconic muscle car with a reputation for speed and flair. In 2002, the Trans Am’s final year of production, Pontiac powered its pony car with an 8-cylinder, 16-valve, 5.7-liter, 347-cubic inch engine called the LS1.

Even today, restoring this all-aluminum engine block is a labor of love. As ls1tech.com, an automotive website, a mechanic shared a story that’s familiar to many do-it-yourselfers (DIYers). For surface finishing cylinder walls, there’s no substitute for BRM Flex-Hone® tools.

Bearing bores are engine components that house the main bearings, mechanical elements with grooves for passing oil to feed-holes in the crankshaft. For optimum engine performance, bearing bores or tunnels must meet tight tolerances and have an oil-retaining surface finish. 

Line boring with a rigid hone is the right choice for bores that are out-of-round or that require significant material removal. To impart an oil-retaining final finish, however, automotive experts like MSB Tuning in Queensland, Australia recommend the “world’s best cylinder bore” – the BRM Flex-Hone® tool. 

Engine cylinders need a substantially smooth surface finish that’s free from cut, torn, and folded metal. Yet cylinder walls can be so smooth that engine performance suffers.

Over time, the up-and-down movement of pistons creates an overly smooth surface finish. Piston rings skate along cylinder walls and fail to seat and seal properly. The “glaze” that forms can also prevent engine oil from adhering properly.    

The solution to these challenges is the Flex-Hone® tool from Brush Research Manufacturing (BRM). This Made in the USA glaze-breaker hone removes burrs, deglazes cylinder walls, and improves surface finish at the same time. That’s why bloggers like The Bug Boys use BRM Flex-Hone® tools for engine rebuilds.

Camaro brake valves can confound even experienced mechanics. Part of the problem is that some of these valves are known by more than one name. For example, metering valves are sometimes called pressure regulator valves or hold-off valves in different GM publications. 

At Muscle Car Research, an on-line automotive community, a mechanic described a successful metering valve rebuild for a 1970 Chevrolet Camaro. To impart the ideal cylinder surface finish, the brake mechanic used a ball hone – a tool that’s better known as the BRM Flex-Hone®. 

Made in the USA by Brush Research Manufacturing (BRM), the Flex-Hone® tool has its share of nicknames. Yet no matter what you call this flexible honing tool, you can improve cylinder surface finish by following some basic guidelines. 

Porsche wheel cylinders support braking in sportscars that pack plenty of power. In classic cars like the Porsche 356, these cylinders have pistons that are connected to brake shoes. If a wheel cylinder lacks the right surface finish, however, more than just piston ring sealing can suffer.       

At the Porsche 356 Registry, an on-line community, the owner of a Porsche 356B asked for advice about honing brake cylinders. A few users suggested honing stones, but a German mechanic recommended the Flex-Hone® tool from Brush Research Manufacturing (BRM).

“I use this tool,” the Porsche mechanic explained. “This works better than all others.”

Honda D-series engines once powered compact cars like the Honda Civic. These four-cylinder aluminum engines were fuel-efficient and lightweight, but could be modified with high-compression pistons for increased power and performance.

At D-series.org, an on-line community for Honda enthusiasts, the owner of 1991 Honda Civic explained how he bought a 1.5L D-Series engine after the original powerplant “died”. The engine rebuilder inspected each cylinder and then asked for advice.

“Everyone said that good honing will take care of the rust and anything else left in the bore,” he said. To finish the cylinder walls, the DIYer used the BRM Flex-Hone® tool. The mechanic admitted he “had some doubts” about flexible cylinder honing, but using the tool made him a believer.