Designing spindle bearings and boxes. Thrust bearings. Ball bearings. Proper metal for boxes. The cast iron box. Early form of boxes. The cylindrical form. Thrust bearings for a light lathe. Experiments with different metals on high speeds.
Curved journals. The involute curve. The Schiele curve. Conical bearings. Adjustments to take up wear. Split boxes. Line-reaming boxes.
What Is a Lathe Spindle?
Lubrication of spindle bearings. The plain brass oil cup. The use of a wick. Oil reservoirs. Loose ring oilers. Chain oilers. Neglect of proper lubrication. Back gearing. Varying the spindle speeds. Triple gearing. Theory of back gearing.Login or Sign Up.High precision air bearing CNC lathe and grinder
Logging in Remember me. Log in. Forgot password or user name? DIY metal spinning lathe; re spindle bearings.
Posts Latest Activity. Page of 2. Filtered by:. Previous 1 2 template Next. Lee in Texas. DIY metal spinning lathe; re spindle bearingsPM. Can bronze bushings take the extra hp and rpm of a metal spinning lathe? I'd like to make one and I was thinking of starting with old lathe parts. It would be great to have a ready-made spindle rather than making a custom one. Tags: None. Lee, Just talked to my friend that rebuilds to antique auto headlights, who spins on a almost daily basis, 2 of the 3 spinning lathes he has from the 40's, have bronze bushings as spindle bearings.
He said that with these lathes, the spindle speeds are not that high, you have to keep the speeds low because the brass will work harden if spun too fast, and motor hp is in the hp range. These machines will spin up to 20" diameter starting size. Comment Post Cancel. I learned metalspinning from someone who'd been doing just that for nearly 50years. He says to prefer bronze bushes to rollerbearings and he very much dislikes ballbearings.
Roller- or ballbearings don't give as nice a finish as do bronze bushings, or so he says They also last a lot longer.
I have to say that personally I dont not have enough experience to notice any difference, but since he spent the last 50 odd years strapped to a lathe with an enormous leather belt Even at 72 he'd still do three or four sets of steel rims for oldtimers and a few silver vases and a batch of aluminium lampshades in a day's work.Spindle bearings must be properly lubricated to maintain a film of lubricant between the rolling elements and the bearing raceways.
There are several methods of lubrication used for spindles. Below you will see the different types and the advantages and disadvantages to each method of machine tool spindle bearing lubrication:. The majority of spindles are greased for life, meaning the only grease needed is that which is installed at the time of assembly.
Grease manufacturers have brought their formulas to the point that the lubricating oils and the agents that carry them are resilient enough to last longer than the bearings expected duty cycle.
However, bearing life can still be dramatically decreased by the introduction of outside influences such as coolant, high heat, metal chips, and grinding swarf—to name a few. Spindles that are not greased for life and require additional grease to be added are uncommon and typically low speed. Grease injected spindles allow for a small portion of grease to be injected into the bearings at a rate determined by the machine tool manufacturer.
This is commonly done with grease cartridges that are pneumatically controlled by the machine PLC. This allows for new grease to replace what is currently in the bearing and the ability to use different grease types in a spindle that may have a combination of angular contact bearings and roller bearings.
Oil lubrication is performed by external equipment and usually carried to the spindle via tubing. These systems use liquid oil, such as Mobil DTE light or equivalent, that is delivered to the spindle in a stream of air.
There are a few different delivery systems, each having its own characteristics:.
One of the first spindle oil delivery systems used for spindles was oil mist. This method uses compressed air to atomize the oil and carry it to the spindle. This oil laden air is pumped through the spindle flowing through the bearings. The system consists of an air regulator attached to a ventury. The ventury often has a clear bubble at the top with a tube that shows the frequency of the drops per minute.
For spindles, an average rate is 20 drops per minute dpm but can vary from 5 dpm to 80 dpm depending on the application. Too high of a rate causes heat and bearing skidding and too low a rate does not allow for enough of an oil film between the rolling elements and raceways.
Most manufacturers we recommend Bijur have a panel with the entire system installed on it. The pump contains the oil reservoir and is set to activate at predetermined intervals.
It produces enough pressure to activate the injector cartridges in the mixing block. The mixing block produces a finely metered drop of oil, usually between. The oil drop is then pushed down the wall of the tubing to the bearings by a steady stream of air. This system requires the oil lines be run very close to the bearings, unlike oil mist systems. This method lubricates the bearings through holes in the inner races of the bearing. Oil is pumped through the shaft, through the bearing, and then recovered by a vacuum system.
Hydrostatic bearings and hydrodynamic bearings are fluid film bearings that rely on a film of oil to create a clearance between the moving and stationary elements. Hydrostatic bearings employ a positive pressure supply that maintains clearance between the rotating stationary elements.Login or Sign Up.
Logging in Remember me. Log in. Forgot password or user name? Spindle bearings for sheldon lathe, anyone have any part numbers? Posts Latest Activity.
Page of 1. Filtered by:. Previous template Next. My sheldon lathe has developed a vibration problem. Cuts that I used to take easily smoothly now cause a horrendous vibration that vibrates anything setting on the lathe right ont othe floor. It is a WS56P, 11" lathe. I have tried tightening down every screw, bolt, fastener that I can find, I have used a brand new carbide bit and get the same vibration. I have sharpened my HSS bits to razor sharpness, same vibes.
This just started recently after I built a tool for pulling bearings off rear axle diff. The tool was made without incident, but since has developed the 'vibe". Does this sound like bad spindle bearings? How do I check them? I can grab the spindle and try to move it up and down, a la how wheel bearings are checked, but I get no discernable movement. Should I put my dial indicator on the spindle nose L00 taper mount while attempting to move it? Actually, that sounds like a smart thing to do.
Anyway, my local driveline shop can get me any bearing and race that timken makes. Does anyone have a timken part for my sheldon? I'd really like to have the new bearings on hand when I pull the old ones out. Any other brands of bearing I should consider?Metalworking usegroup. I was primarily interested in any potential changes needed for an HLV-H, and in clarifying some questions I had about certain statements which were not clear to me, but the details and clarifications he gave me seem to be applicable to most of the original list of Hardinge products.
These changes are incorporated in the procedure below. This is not a difficult process, but it does require an understanding of basic machining and maintenance techniques. The main intent is to give the reader the level of confidence needed to do the job himself. Please note that this is written with the later "two bearing" design in mind.
Some older Hardinge lathes, such as the HLV-B, use three bearings on the spindle — an angular contact pair on the front and a less expensive ball bearing at the rear.
In this design, all of the axial force on the spindle is absorbed by the front bearing pair. That is, they act as a thrust bearing as well. The rear bearing is designed in such a way that it is captive along the spindle but the outer race floats inside the bore of the headstock. On that spindle, it is a pain because there are two locking ring nuts at the extreme left end that hold the entire stack of inner races and spacers tight on the spindle.
These nuts are a castellated affair that is recessed inside the headstock casting, and requires a special wrench to be fabricated, while the later nuts are conventional pin types.
Hardinge does improve their designs as they go! A couple of tapered wooden framing shims are useful for getting the plastic types off. It has two small Allen screws diametrically opposed.
Loosen them up and tap the cover with a soft hammer. It should come loose. Put an Allen wrench in one of the screws and pull while you are tapping. On the HLV machines, it will be necessary to remove the gearbox casting on the left end to gain needed access to the spindle.
The drive pulley is now exposed. Open motor compartment, and remove the nut from the elevator screw on the motor plate. If the lathe has an electric brake, remove the two cap screws holding it down and get it out of the way.
The variable speed drive yoke floats free. Push the axle towards the tailstock. The remote speed control units like the HLV-H have a motor driven jackscrew that you can raise the yoke with.
Pushing the axle as far to the right as possible allows the axle to come completely out of the left bearing, leaving a gap big enough to slip the flat belt out. Once the belts are removed, check the disk bronze center for slop They can be bored and bushed if needed.
Using a couple stiff wire hooks, lift the secondary flat belt from the spindle pulley, and holding your tongue in the proper corner of your mouth, pull it out the top of the headstock the rear opening or end, as appropriate. Note that on earlier models of the HLV-H, you must also remove the reverse tumbler gear to get the belt entirely out of the machine.
The manual will show you the short procedure for that. Using a pin wrench, remove the nut called a "spindle nut" in the Hardinge HLV-H parts manual - see drawing below holding the spindle pulley to the spindle. Tricky part here - sometimes the spindle pulley comes out very easily.
You can sometimes use the flat end of a crowbar, from the motor compartment, to free the pulley. Careful where you put it!Learn something new every day More Info Lathes are used to cut, shape and machine wood or metal, and come in a wide variety of configurations and sizes.
The bits, or cutting toolsmay be integrated into the lathe, fitted as an accessory or hand-held. The lathe spindle is, consequently, the part of the machine that makes it a lathe. The lathe spindle ordinarily consists of a plate or disc either mounted to a shaft or with an integrated shaft, and incorporating a chuck configured to grasp the particular stock to be turned. The stock to be worked using the lathe is placed end to end, usually horizontally, above the lathe bed, with one end inserted into the spindle chuck and the other into the freewheeling tailstock located at the opposite end of the bed from the spindle.
The spindle and tailstock are maneuvered toward each other thus jamming the stock. The lathe is started and the spindle begins to rapidly rotate. Next, the cutting bits are engaged with the stock and the turning of the material is accomplished through the stationary bits cutting and shaping the material that is being held and spun by the spindle.
Chapter VI. Lathe Design : The Spindle Bearings, The Back Gears, And The Triple Gear Mechanism
In all modern lathes, the lathe spindle axlewith its attendant gearing, bearings, adjusting screws, and, in many cases, its motor, is contained in the headstock.
Essentially, the headstock is a housing that protects the enclosed machinery from contamination and damage. The headstock housing also protects the operator from injury due to improper operation or a malfunction of the machine. Metal lathes, those that are used to precisely machine metal stock in high volume operations, are large machines and will, by necessity, have sizable, heavy-duty spindles that are turned by electric motors. Such heavyweight spindles are better able to withstand the hefty stresses and strains consistent with machining metal stack.
Metal-working lathes are available for the home or small shop as well, but only used for very low-volume, light-duty applications, since the spindles and bearings which take the brunt of the stress in the machining process are considerably downsized. A woodworking lathe and its lathe spindle need not be so large or sturdy, thus, except for high-volume production machines, such smaller lathes are generally suitable for a home workshop.
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Thank you for helping to improve wiseGEEK! View slideshow of images above. Watch the Did-You-Know slideshow. Follow wiseGEEK. Did You Know? Excessive neural activity has been linked to a shorter lifespan; meditation could help quiet an overactive brain.For critical applications these bearings are stocked as universally ground duplex pairs with standard preloads and as single row bearings. Duplex pairs can be mounted back-to-back, face-to-face or tandem depending on the loading expected.
Due to high speeds, these bearings usually require phenolic retainers, which have either a stepped or cylindrical pocket design. Ceramic ball bearings have been proven to last up to 5 times longer than conventional steel ball bearings and lower operating temperatures help extend lubricant life.
CNC Mill Spindle: Bearings, Belt Drive, VFD, ATC, and Design Notes
Cylindrical rollers distribute loads across a broader surface allowing for high radial load capacity and higher speeds. Single row and double row cylindrical bearings are used primarily for precision machine tools. Precision radial bearings support axial loads in a single direction. They are high rigidity and have a high load capacity. This type of bearing is used for applications requiring high running accuracy and tight dimensional tolerances. Use of nonmetallic retainers such as phenolic can help to achieve higher speeds.
Ball screw support bearings are designed to provide maximum axial rigidity and improved feeding accuracy for use with precision ball screws. They are high accuracy angular contact thrust bearings which are superior to combinations of standard angular contact bearings or arrangements of radial and thrust bearings for ball screw applications. This type of bearing can accommodate axial loads in both directions, and are done in a separable design. Double direction bearings can handily high axial forces and have a high rigidity.
Request Quote 0. Unit of Measure:. Pump Make:. Pump Model:. Outside Dimension:. View Diagram. Cylindrical Roller Ball Bearings Ball Bearing Description Cylindrical rollers distribute loads across a broader surface allowing for high radial load capacity and higher speeds. Ball Screw Support Ball Bearings Ball Bearing Description Ball screw support bearings are designed to provide maximum axial rigidity and improved feeding accuracy for use with precision ball screws.
Ball Bearing Categories Inch Metric.