XSlide begins as an extrusion of aluminium alloy with a straightness tolerance of half the normal commercial tolerance. Subsequent machining and lapping operations produce a very high degree of straightness and parallelism in the dovetail ways.
The size of the slide selected for a given application will depend on user requirements. The chart below provides maximum dynamic load capacities for each model for three different load positions.
Orientation: Up, Down, Left and Right
The reference position for linear UniSlide Assemblies is with the base down, the slider up, and the knob, if any, facing the user.
Using a 6262-T6 aluminium alloy extrusion which has a straightness tolerance of half the normal commercial tolerance, the subsequent machining and lapping operations are designed to secure a high degree of straightness and parallelism in the dovetail ways. There are essentially three types of deviation from straightness that can occur.
Referring to a UniSlide Assembly resting base down on a flat surface with its linear motion or longitudinal direction, X, there can be a departure from straightness in the upward direction, Z, which is designated as the bow error. There can be a deviation from straightness in the horizontal direction, Y, designated as horizontal run-out, or simply run-out. There can also be a twist in the direction of the slide, X. The upper limits for these three deviations from straightness as determined by our manufacturing processes are:
Bow* < 0.05mm per 300mm
Run-Out < 0.025mm per 300mm
Twist 1 mill radian per foot
*As installed, bow can be affected by the degree of flatness of the supporting surface and relative tension in the mounting screws.
Reduced straightness tolerances, in the order of one half of the nominal values above, are available. LG Motion will select, measure and certify UniSlide Assemblies for the customer at an extra charge of £25/100mm.
The standard aluminium alloy dovetail base and low friction polymer pads of the slider provide excellent performance as a bearing material combination. Unlike ball screw slide mechanisms, no lubrication is required. Under light to moderate loads, sideways play caused by wear during the first 30,000 cycles of operation will be approximately 0.00015 inches. Wear after that is reduced, to approximately 0.00125mm over the next 50,000 cycles. Sliders are equipped with adjustment screws to compensate for wear, if necessary. For harsh environments and/or a higher number of cycles, UniSlide Assemblies with hard coat anodized ways are available. For clean room environments we recommend electroless nickel plating.
The regular UniSlide Assemblies are made with Type 303 stainless steel fasteners. Lead screws are made of 303 stainless steel and are slightly magnetic. Where an exceptionally high degree of nonmagnetic character is required, LG Motion may supply plated brass fasteners and brass lead screws. Rotary tables have several essential steel ball bearing units. Electric motors are inherently magnetic.
For further information, please contact us.
Material substitutions for drive nuts, lead screws and thrust bearing are possible. Drive nuts are available in brass, oil-impregnated bronze, and, for high temperature or radiation applications, in Vespel. Bearings can be manufactured from Delrin. Brass lead screws are available in a limited pitch selection.
UniSlide linear and LG Series Rotary Tables can be used in a vacuum to 10-6 torr with modifications. We recommend substituting duPont Vespel® for the standard Delrin® AF drive nut in a high vacuum. We can clean the bearings and replace the standard lubrication with a high vacuum lubricant, however, we do not have clean room facilities for ultra-clean applications. In that case, we suggest the critical user reclean the assemblies. Check with us for pricing.
Normal temperature range is 40-250°F
The torque requirements of a light load on a horizontal assembly ranges from 20 to 30 oz.-in. and is affected by the pitch of the lead screw. When the maximum motor torque is converted into the direct (thrust) force in the direction of the lead screw axis, a figure designated as the maximum thrust load is obtained. This value is listed in the lead/translation speed tables. The maximum thrust load is limited by the lead screw thrust bearings design.
Protective Limit Switch Assembly
Protective limit switches are included to prevent any damage to the lead screw, drive nut at the end of slider travel, any User component that is mounted to the slide or where any damage to the User could result. This includes most applications except those with small stepper motors.
Catalogue lengths are those listed, but longer units are also available. In-between lengths are available on special order. All slides are manufactured by us, so if you require any modifications, just let us know – we’re here to help you.