SRI international: Abacus drive Edit Robotics engineers at SRI International in Silicon Valley have developed the first new rotary transmission design since the invention of the Harmonic Drive gear. Learn more: Zero backlash high gear ratio. From Tracked_vehicle#Variable_speed_drive_shaft SRI’s Abacus drive has beads that roll in and out of a groove with a variable diameter. This causes the beads to effectively change their diameters depending on where in the groove they are, resulting in the same kind of cycloidal motion that you see in Harmonic Drive gears, but with less backlash(zero) than a harmonic drive and much less complex manufacturing.

diy Edit

Magazines Edit

HONING TECHNIQUES, by Bob Paule. Try honing your cylinders instead of lapping them.

worm gears Edit squaring off a one cm disk, it is orthogonally aligned against a back plate that mounts flush between the chuck jaws. 13min. by max runout

Drilling small holes Edit Accupro - 1/2 Inch Shank Diameter Straight Shank Micro Drill Chuck Adapter and Chuck 1/64 to 5/32 Inch Drill Chuck Capacity from micro drilling small holes without breaking the drill bit by Joe Pieczynski

Max runout channel Edit part.5 on making gears in workshop. n part 5 of our series on automating the gear making process, we build a device to measure the gears we have made so far, improve the process and make some new gears. Shows mechanism for testing depth of gear teeth. plastic shredder.

Drill center hole Edit I am going to try to lift substantially more weight with a wiper motor than the last try with a belt drive.


The Concentric Maxi Torque keyless hub-to-shaft connection system. ,, Engineers at Custom Machine and Tool Co., Inc. found that fasteners used to connect components to high speed shafts had to have lower intertia and create fewer vibrations. We also knew that component alignment, accuracy, holding ability and runout became critical at higher speeds. When no other company could offer a compact bushing for shafts less than an inch in diameter, CMT was up to the task. We decided to design, build and patent one.

Tracked platform Edit Pivot platform uses slew bearing.

Wheels Edit

Knife edge bearings Edit

shaft coupling Edit Key shaft to spline shaft coupling method. Connecting a motor to a gearbox in a precise manner with an alignment plug. Linked from,

suppliers Edit

Tubing, chromed rods Gears , pulleys Worm gearbox Tamiya pan/tilt platform 20kg

“ServoBlocks”, n.d.

“Slip Ring 6x2A (6 Wires, 2 Amps) 4A Available | eBay”, n.d. “Toothed Timing Pulleys and Belts”, n.d. $1.50 pack of 50 and bevel $1.7 for one. Steel shaft pack of 50 2mm diameter for worm gear $1.2 Bevel gears for gates

Gear hobbing Edit

See Machine design. Links on making exact worm gear and matching worm wheel for telescope star tracking. Download zipped files on taper, pitch calculations for gear hobbing.

Chris Heapy Edit

Claudio Grassi Edit

Myfordboy Edit

Planetary gear Edit

Mrpete222 Edit grinding a tool bit.

Hour glass Edit (Scan design with laser scanner and reproduce 3d printer) Kinematics’ patented hourglass design is unique because it can withstand a survivability load that is four to nine times greater than loads carried by typical slewing drives. The special hourglass shape of the drive allows more teeth to be engaged at one time, enabling much higher torque endurance. Our technology delivers a stronger and more durable drive so your equipment can perform longer and more reliably.

plastic ball bearing Edit xiros Free from maintenance and lubricants, suitable for extreme environments

Xiros plastic ball bearings from igus are designed for applications where the use of grease or lubricants is prohibited. The food and drinks industry, in particular, bans the use of such substances altogether. The design of igus xiros ball bearings is the same as conventional steel bearings, consisting of an inner and outer race, a cage and a number of balls; the only difference being that the races and cage are made from igus tribological polymer materials. These plastic materials are self-lubricating and thus negate the need for lubricants. 3d printing ball bearings 0 printing gears 1 printing house

Worm gear Edit Description

Ok, once you have an involute gear library AND a trapezoid thread library, you can easily make the simplest of worm drives, i.e. the non-throated kind.

Like all worm drives, the gear advances by one tooth for each revolution of the screw but with non-throated ones, there is only a single point of contact at any one time, and so torque and wear capabilities are limited.

UPDATE: As I pointed out in the comments, AFAIK a trapezoidal profile for the worm screw is all you need to match the worm gear's involute.

To make them mesh, all I did was to make sure that: 1. the pitch is the same (distance from crest to crest), 2. the pressure angle of the gear is equal to the angle of the sides of the screw profile, 3. the distance between screw and gear is equal to the gear's radial pitch plus the screw's mid-profile radius, and 4. the twist on the gear is equal to the gear's pitch radius divided by the screw's mid profile radius, with a sign depending on the screw's handedness.

Many methods have been used for control of backlash in geartrains. George W. Michalec's book Precision Gearing: Theory and Practice, published in 1966, has a good description of many different methods. Most have disadvantages such as increased size, weight, and cost. Examples are split, spring-loaded scissor gears and the use of auxiliary geartrains. from

ball screw Edit

moved to Machine design

Bearing numbering Edit

674ZZ Shielded Ball Bearings 4mm x 7mm x 2.5mm 10 Ball Bearings 674ZZ Shielded Ball Bearings, the inner diameter is 4mm, outer diameter is 7mm and the width is 2.5mm, Bearings are made of Chrome Steel.

This 608ZZ shielded 8x22x7 miniature ball bearing is a single-row bearing for supporting radial loads. (inner x outer x width)

  • MR105-ZZ, 5x10x4 mm, Radial Bearing

links Edit flange bearings f623zz