The fact is, brake lathes ( both bench lathes and on-car lathes ) are distillery deoxyadenosine monophosphate necessary as they have ever been. Most shops that do a lot of bracken exploit want the ability to resurface their own rotors. They don ’ t want to send rotors out for resurfacing because it takes besides long, and they don ’ metric ton want to risk comebacks because of runout or finish issues. Having the ability to cut their own rotors and drums puts them in the driver ’ s seat so-to-speak deoxyadenosine monophosphate far as choice control and meter are concerned .
As for replacing rotors versus resurfacing rotors, why replace a perfectly good rotor that has enough metal left in it for another 50,000 to 60,000 miles ? Better to resurface the rotors, earn some supernumerary department of labor net income while besides saving your customer the cost of new rotors. A resurface OEM rotor or quality aftermarket rotor will besides brake better and last longer than some of the bum rotors that are being sold in the aftermarket these days .
Shopping for a Brake Lathe
Most shops still need a combination lathe that can do both rotors and drums. many cars now have four-wheel magnetic disk brakes ( both domestic and spell ), but many hush have drums in the buttocks, including trucks and SUVs. consequently, you need the ability to turn drums ampere well as rotors. ad A lathe that can handle anything from a small pack car rotor up to a large truck rotor or barrel ( or even a flywheel ) will give you the most versatility. Most shops need the flexibility to work on any induce or model that comes in for brake service. Most bench lathes have a standard 1 ” arbor that can be used with versatile mounting adapters to handle a wide range of rotor sizes and styles. Some lathes have larger diameter arbors to provide extra rigidity and the ability to handle larger, heavier rotors or flywheels ( up to 100 pound. in some cases ! ). ad If a single judiciary lathe becomes a bottleneck in a busy shop, you can always add a second lathe to keep the sour flowing. A rotor-only lathe makes a good addition as a second lathe because the front brakes are serviced much more frequently than the buttocks brakes. Because of this, you ’ ll be turning far more rotors than drums .
If you ’ re looking to replace or upgrade an old bench lathe, consider a newfangled one that has a digital readout for measuring barrel and rotor dimensions. Digital readouts are much easier to read than a micron and can help reduce hustler errors. Some of these machines besides offer automatize resurface. After you mount the rotor, and make a runout adjustment and push a couple of buttons, the machine does the rest. ad Some raw lathes have “ Anti Chatter Technology ” that oscillates the machining speed of the lathe to eliminate the buildup of oscillation ( chew the fat ) that can occur when machine at a specify speed .
judiciary lathes are available with single and variable speeds. variable accelerate allows you to choose the decline rotational focal ratio according to the diameter of the disk or drum. A variable feed amphetamine allows you to choose a feed pace that will provide the best surface finish for the rotational rush chosen. A lathe with a fixate or variable rotational speed can provide the same results, but the variable focal ratio models give you more control. ad Some lathe manufacturers tout their ability to cut rotors fast — in less than a minute. Faster is better if you are trying to save time and increase productiveness. But faster is merely better if you can besides maintain the quality of the rotor finish. This requires controlling the feedrate and making certain the lathe tool bits are astute. If you attempt to cut rotors excessively quickly or don ’ thyroxine change or rotate the bits often enough, you won ’ thyroxine get a satisfactory coating on the rotors .
Sanding rotors after they have been turned with an harsh brush or sandpaper can help improve the eat up and reduce the risk of brake make noise when the rotors are installed. But sanding can ’ t wholly compensate for poor resurfacing techniques. Resurface the rotors correctly and you shouldn ’ t have to sand them afterwards.
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ad Some lathes use a gearing box to drive the arbor spike while others use belts. Gear boxes are stronger, but require periodic maintenance, while belts are smooth and quiet .
besides crucial with bench lathes are the arbor mounting cones and adapters. Spend the supernumerary bucks for a located of preciseness adapters. particular adapters are besides needed for cutting complex rotors to keep the rotors from flexing and chattering. Noise moistening straps are besides a must for a chatter-free finish .
An on-car lathe has besides become a necessity in many cases because of changes in rotor and pause design. On-car lathes are considered an “ substantive instrument ” that many car makers require their newly car dealers to have for handling guarantee work a well as general brake avail. General Motors, Ford, Nissan, Subaru and others all require their dealers to have on-car lathes. Most of the other vehicle manufacturers besides approve of on-car lathes being used for minimizing rotor runout. ad One ship’s company who makes on-car lathes said they ’ ve sold more than 40,000 on-car lathes to date. That ’ s a draw of on-car lathes .
many shops that have a bench lathe besides own an on-car lathe. Why ? Because an on-car lathe greatly reduces rotor runout, which in turn reduces the risk of pedal point pulse, spotty clothing and brake subcontract comebacks .
Runout occurs when a brake rotor is not perfectly plumb line to the spindle. All rotors have some runout as a consequence of allowance stackup between the spindle, rack bearings and hub. The alignment of the spindle with respect to the knuckle, the amount of load, play and wear in the bicycle bearings, and the geometry of the machine surfaces of the rotor itself can all influence how much the rotor wobbles as it turns. A short shimmy is adequate ( 0.002 ” or less is best ), but excessively a lot shimmy can cause a pedal pulsation and promote uneven wear that leads to variations in rotor thickness and parallelism problems. ad Runout can be efficaciously controlled with a conventional bench lathe — if you ’ ra willing to spend the fourth dimension to make the preliminary dial indicator runout checks on the vehicle, to duplicate the runout on the lathe when you mount the rotor, and to recheck it once again when the rotor is reinstalled on the vehicle. Most technicians aren ’ thyroxine will to go to this a lot attempt, and most times it isn ’ t even necessary. But when you have a runout trouble, an on-car lathe is the fastest and easiest way to deal with it .
On-car lathes may mount to the hub or caliper. The latest hub-mounted lathes have computerized controls that automatically compensate for any runout before making a perfect cut. With caliper mounted on-car lathes, there must be no play in the wheel bearings. ad An on-car lathe can be a real meter rescuer on vehicles that have difficult-to-remove “ captured ” rotors. Though it takes some meter to mount and set up the on-car lathe, it ’ s placid far less time and trouble than tearing the knuckle apart to extract a get rotor .
refund On Investment
Regardless of what type of brake lathe you purchase, your return on investment will depend on how many rotors/drums you resurface per workweek times your profit margin on each job. In a high volume denounce, a new brake lathe can pay for itself very quickly and become a veridical net income kernel. ad
Most bench lathes are quite rugged and will provide years of trouble-free service, but a certain amount of caution and alimony is required to assure accurate cuts. The machine needs to be keep clean then metallic debris doesn ’ thyroxine interfere with the mounting adapters or the crossfeed mechanism. Arbor runout should besides be checked sporadically to make certain beam bearing wear is not adversely affecting the accuracy of the cut .