{"id":1820,"date":"2026-04-08T06:19:26","date_gmt":"2026-04-08T06:19:26","guid":{"rendered":"https:\/\/wormwheelgear.top\/?p=1820"},"modified":"2026-04-08T06:23:57","modified_gmt":"2026-04-08T06:23:57","slug":"how-to-calculate-worm-gear-ratio-complete-engineering-guide-with-worked-examples","status":"publish","type":"post","link":"https:\/\/wormwheelgear.top\/da\/how-to-calculate-worm-gear-ratio-complete-engineering-guide-with-worked-examples\/","title":{"rendered":"How to Calculate Worm Gear Ratio \u2014 Complete Engineering Guide with Worked Examples"},"content":{"rendered":"

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How to Calculate Worm Gear Ratio \u2014 Engineering Guide with Worked Examples<\/h1>\n

Getting the gear ratio wrong in a worm drive specification wastes more money than the gear set itself \u2014 wrong output speed means wrong motor selection, wrong torque means undersized components, and wrong self-locking assumption means a brake retrofit. This guide walks through every calculation you need, with real numbers in every example.<\/p>\n

Get Ratio Calculation Support<\/a><\/p>\n<\/div>\n<\/div>\n

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Why a Ratio Calculation Error Is More Expensive Than the Gear Itself<\/h2>\n

A design engineer specifying a worm gear drive for a solar tracker sets the target output speed at 0.25 RPM from a 1450 RPM motor \u2014 requiring a 5800:1 total ratio. He calculates the worm gear ratio as 58:1 from a misread of the tooth count (58 teeth on the wheel, but a 2-start worm \u2014 actual ratio 29:1). The motor runs, the tracker moves, and the actual output speed is 0.5 RPM instead of 0.25 RPM. The tracker over-travels its target angle and the control system hunts. The gear sets are already installed on 200 tracker units before the error is identified.<\/p>\n

The gear set replacement cost is significant. The project delay cost is larger. But the root cause was a single computational error that took less than a minute to make: confusing tooth count with ratio by ignoring the worm start count. This guide prevents that error by explaining the calculation completely \u2014 including the common trap of counting worm thread turns instead of worm starts.<\/p>\n

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\"Messing<\/div>\n

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The Fundamental Formula \u2014 And the One Error That Causes Most Mistakes<\/h2>\n
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Worm Gear Ratio Formula<\/p>\n

i = z2 \u00f7 z1<\/p>\n

Where:<\/strong><\/p>\n

\u25a0 i = gear reduction ratio (output rotations per one input rotation: i = input RPM \u00f7 output RPM)<\/p>\n

\u25a0 z2 = number of teeth on the worm wheel<\/p>\n

\u25a0 z1 = number of starts<\/strong> on the worm shaft \u2014 NOT the number of thread turns or thread passes visible on the worm shaft<\/p>\n<\/div>\n

The single most common calculation error is using a worm thread turn count or visible thread count in place of the start count. A single-start worm with 40 thread turns wrapped around the shaft is still z1 = 1. A two-start worm with 20 thread turns per start is still z1 = 2. The number of turns on the worm is a function of the worm length and lead angle \u2014 it has nothing to do with the start count that determines the gear ratio.<\/p>\n

How to identify the number of starts on an existing worm shaft: look at the end face of the worm. Count the number of thread initiation points visible at the end face \u2014 each point where a thread begins is one start. One initiation point = single-start. Two initiation points, spaced 180 degrees apart = two-start. Three initiation points, spaced 120 degrees apart = three-start. This is the only reliable way to determine start count from a physical part when the drawing or part number is not available.<\/p>\n

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Worked Example 1 \u2014 Simple Ratio from Known Components<\/h2>\n
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Given:<\/p>\n

\u25b7 Worm wheel tooth count: z2 = 40<\/p>\n

\u25b7 Worm start count: z1 = 1 (single-start worm \u2014 one thread initiation point at the end face)<\/p>\n

Calculation:<\/p>\n

i = z2 \u00f7 z1 = 40 \u00f7 1 = 40:1<\/strong><\/p>\n

Verification:<\/p>\n

Motor speed 1450 RPM \u2192 output speed = 1450 \u00f7 40 = 36.25 RPM<\/strong><\/p>\n

In other words: the worm makes 40 full rotations for every one rotation of the wheel. At 1450 RPM motor speed, the wheel turns once every 1.655 seconds.<\/p>\n<\/div>\n

Worked Example 2 \u2014 Full Drive Calculation Including Torque and Efficiency<\/h2>\n
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Application: Solar tracker azimuth drive<\/p>\n

Given:<\/strong> Motor = 90W, 1400 RPM; required output speed = 18 RPM; estimated worm drive efficiency at this ratio = 0.78<\/p>\n

Step 1 \u2014 Required ratio:<\/p>\n

i = input RPM \u00f7 output RPM = 1400 \u00f7 18 = 77.8:1<\/strong><\/p>\n

Round to nearest practical tooth count: z2 = 78 teeth, z1 = 1 start \u2192 actual ratio = 78:1 \u2192 output speed = 1400 \u00f7 78 = 17.95 RPM<\/strong> (acceptable)<\/p>\n

Step 2 \u2014 Output torque calculation:<\/p>\n

Motor input torque = (Motor power \u00d7 60) \u00f7 (2\u03c0 \u00d7 motor RPM) = (90 \u00d7 60) \u00f7 (2\u03c0 \u00d7 1400) = 0.614 Nm<\/strong><\/p>\n

Output torque = motor torque \u00d7 ratio \u00d7 efficiency = 0.614 \u00d7 78 \u00d7 0.78 = 37.3 Nm<\/strong><\/p>\n

Step 3 \u2014 Motor sizing verification:<\/p>\n

Required output torque from wind load analysis: 35 Nm<\/p>\n

Calculated output torque: 37.3 Nm<\/p>\n

Margin = (37.3 – 35) \u00f7 35 = 6.6% \u2014 marginal.<\/strong> Consider 120W motor or verify wind load calculation. An engineering margin of at least 25% above maximum wind torque is recommended for outdoor tracker drives to account for gust factors and cold-start lubricant viscosity increase.<\/p>\n<\/div>\n

Worked Example 3 \u2014 Working Backwards from Target Ratio to Tooth Count Selection<\/h2>\n
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Application: CNC 4th-axis rotary table<\/p>\n

Given:<\/strong> Required ratio = exactly 36:1 (convenient for indexing 360\u00b0 in 10\u00b0 increments \u2014 one motor revolution = 0.1\u00b0 output); self-locking required<\/p>\n

Step 1 \u2014 Determine start count:<\/p>\n

Self-locking required \u2192 use z1 = 1 (single-start worm \u2014 the lowest lead angle for maximum self-locking reliability)<\/p>\n

With z1 = 1: z2 = i \u00d7 z1 = 36 \u00d7 1 = 36 teeth on wheel<\/strong><\/p>\n

Step 2 \u2014 Check for undercutting (minimum tooth count):<\/p>\n

For a worm wheel, the minimum practical tooth count to avoid severe undercutting is approximately 17\u201320 teeth. 36 teeth is well above this limit \u2014 no undercutting concern.<\/p>\n

Step 3 \u2014 Alternative: could a 2-start worm also work?<\/p>\n

With z1 = 2: z2 = 36 \u00d7 2 = 72 teeth \u2192 wheel becomes physically larger (more material, higher cost, larger housing required)<\/p>\n

Also: 2-start worm has approximately 2\u00d7 larger lead angle \u2192 may not self-lock reliably at all lubrication conditions<\/p>\n

Conclusion: z1 = 1, z2 = 36 is the correct specification.<\/strong> It is compact, reliably self-locking, and gives the exact 36:1 ratio required.<\/p>\n<\/div>\n

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\"snekkegearstruktur<\/div>\n

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How Gear Ratio Affects Efficiency \u2014 The Numbers You Need for Motor Sizing<\/h2>\n

Worm gear efficiency decreases as the reduction ratio increases. This is a geometric consequence: a higher ratio requires a shallower lead angle, and a shallower lead angle directs more of the contact force into friction rather than useful output torque. The relationship is continuous and predictable \u2014 knowing the ratio, you can estimate efficiency within a useful range for motor sizing purposes.<\/p>\n

\n\n\n\n\n\n\n\n\n\n\n\n
Ratio (single-start worm)<\/th>\nTypical Lead Angle<\/th>\nApproximate Efficiency (oil lubricated, bronze wheel)<\/th>\nSelf-Locking?<\/th>\n<\/tr>\n<\/thead>\n
5:1<\/td>\n~11\u00b0<\/td>\n88 \u2013 93%<\/td>\nNo \u2014 lead angle exceeds friction angle<\/td>\n<\/tr>\n
10:1<\/td>\n~5.5\u00b0<\/td>\n82 \u2013 89%<\/td>\nMarginal \u2014 verify at operating temperature<\/td>\n<\/tr>\n
20:1<\/td>\n~3.0\u00b0<\/td>\n76 \u2013 84%<\/td>\nYes \u2014 reliable with mineral oil lubrication<\/td>\n<\/tr>\n
30:1<\/td>\n~2.0\u00b0<\/td>\n72 \u2013 81%<\/td>\nYes \u2014 reliable<\/td>\n<\/tr>\n
50:1<\/td>\n~1.2\u00b0<\/td>\n66 \u2013 76%<\/td>\nYes \u2014 reliable<\/td>\n<\/tr>\n
80:1<\/td>\n~0.8\u00b0<\/td>\n60 \u2013 72%<\/td>\nYes \u2014 strong self-locking<\/td>\n<\/tr>\n
100:1<\/td>\n~0.6\u00b0<\/td>\n55 \u2013 68%<\/td>\nYes \u2014 very strong, but efficiency is low<\/td>\n<\/tr>\n<\/tbody>\n<\/table>\n<\/div>\n
Motor sizing rule of thumb:<\/strong> For ratios above 20:1, use \u03b7 = 0.75 as a conservative motor sizing estimate when specific efficiency data is not available. This gives T_motor = T_output \u00f7 (i \u00d7 0.75). If the motor selected with this estimate runs at less than 60% of rated load in service, the drive is oversized \u2014 but the system will work. Using \u03b7 = 1.0 (ignoring efficiency) when sizing the motor is the error that causes overheating and motor tripping in service.<\/div>\n

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Multi-Start Worms \u2014 When to Use Two or Three Starts<\/h2>\n

A multi-start worm increases the lead angle for the same ratio, improving efficiency at the cost of reduced (or eliminated) self-locking. The decision between single-start and multi-start is primarily driven by whether self-locking is required and what efficiency is acceptable.<\/p>\n

\n\n\n\n\n\n\n\n
Target Ratio<\/th>\nUsing z1 = 1 (single-start)<\/th>\nUsing z1 = 2 (two-start)<\/th>\nWhen to Prefer Two-Start<\/th>\n<\/tr>\n<\/thead>\n
20:1<\/td>\nz2 = 20, ~3\u00b0 lead angle, ~78% \u03b7<\/td>\nz2 = 40, ~6\u00b0 lead angle, ~86% \u03b7<\/td>\nWhen self-locking not required and efficiency matters; accepts larger wheel diameter<\/td>\n<\/tr>\n
10:1<\/td>\nz2 = 10, ~5.5\u00b0 lead angle, ~84% \u03b7<\/td>\nz2 = 20, ~11\u00b0 lead angle, ~91% \u03b7<\/td>\nWhen self-locking definitely not required; when efficiency loss at 10:1 single-start is unacceptable<\/td>\n<\/tr>\n
5:1<\/td>\nz2 = 5, ~11\u00b0 lead angle, ~90% \u03b7<\/td>\nz2 = 10, ~22\u00b0 lead angle, ~94% \u03b7<\/td>\n5:1 is unusual for worm drives \u2014 consider helical gear if parallel shaft is acceptable<\/td>\n<\/tr>\n<\/tbody>\n<\/table>\n<\/div>\n

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Production Capability<\/h2>\n\n\n\n\n
\"snekkegearv\u00e6rksted<\/td>\n\"snekkegearv\u00e6rksted<\/td>\n<\/tr>\n
\"snekkegearv\u00e6rksted<\/td>\n\"snekkegearv\u00e6rksted<\/td>\n<\/tr>\n<\/tbody>\n<\/table>\n

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Calculating Whether Your Ratio Will Self-Lock \u2014 The Critical Check<\/h2>\n

Self-locking is not guaranteed for all ratios \u2014 it must be checked against the friction angle of the specific material and lubricant combination. The check is straightforward:<\/p>\n

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Self-Locking Check Procedure<\/p>\n

Step 1:<\/strong> Determine the lead angle \u03bb = arctan(lead \u00f7 (\u03c0 \u00d7 d1)), where lead = number of starts \u00d7 axial pitch, and d1 = worm pitch diameter.<\/p>\n

Step 2:<\/strong> Estimate friction coefficient \u03bc for your material and lubricant combination:<\/p>\n

\u25c8 Hardened steel worm + tin bronze wheel + ISO VG 220 oil at 20\u00b0C: \u03bc \u2248 0.05\u20130.08<\/p>\n

\u25c8 Same at 75\u00b0C (summer operating temperature): \u03bc \u2248 0.04\u20130.06<\/p>\n

\u25c8 Dry (no lubrication): \u03bc \u2248 0.12\u20130.18 (much stronger self-locking but very high wear)<\/p>\n

Step 3:<\/strong> Calculate friction angle \u03c1’ = arctan(\u03bc \u00f7 cos \u03b1), where \u03b1 = pressure angle (20\u00b0 standard).<\/p>\n

Step 4:<\/strong> Compare \u03bb and \u03c1’:<\/p>\n

\u25c8 If \u03bb less than \u03c1’ \u2192 self-locking: the drive will not back-drive under the specified conditions<\/p>\n

\u25c8 If \u03bb greater than \u03c1’ \u2192 not self-locking: back-driving is possible<\/p>\n

\u25c8 If \u03bb is within 1.5\u00b0 of \u03c1’ \u2192 borderline: do not rely on self-locking as a safety feature<\/p>\n<\/div>\n

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Worked Example \u2014 Self-Locking Check for Solar Tracker at 80\u00b0C Housing Temperature<\/p>\n

Given: M6 worm, single-start, d1 = 48 mm (standard proportion), axial pitch = \u03c0 \u00d7 m = 18.85 mm, lead = 1 \u00d7 18.85 = 18.85 mm<\/p>\n

Lead angle: \u03bb = arctan(18.85 \u00f7 (\u03c0 \u00d7 48)) = arctan(18.85 \u00f7 150.8) = arctan(0.125) = 7.1\u00b0<\/strong><\/p>\n

Friction coefficient at 80\u00b0C with synthetic PAO oil: \u03bc = 0.045<\/p>\n

Friction angle: \u03c1’ = arctan(0.045 \u00f7 cos 20\u00b0) = arctan(0.045 \u00f7 0.940) = arctan(0.0479) = 2.7\u00b0<\/strong><\/p>\n

Comparison: \u03bb (7.1\u00b0) is greater than \u03c1’ (2.7\u00b0) \u2192 NOT self-locking at 80\u00b0C with this lubricant<\/strong><\/p>\n

Conclusion: This worm shaft requires a smaller pitch diameter (to increase lead angle would be wrong \u2014 lead angle is already too large) or a smaller start count is not the fix here. The fix is: reduce pitch diameter to reduce lead angle. At d1 = 80 mm: \u03bb = arctan(18.85 \u00f7 251.3) = 4.3\u00b0 \u2192 still greater than 2.7\u00b0 at 80\u00b0C. At d1 = 100 mm: \u03bb = 3.4\u00b0 \u2192 margin is only 0.7\u00b0 \u2014 still risky. Correct solution: use higher viscosity lubricant (\u03bc = 0.065 at 80\u00b0C with ISO VG 460 oil \u2192 \u03c1’ = 4.0\u00b0 \u2192 margin 0.6\u00b0 with d1 = 80 mm). Or use a higher pitch diameter (d1 = 150 mm: \u03bb = 2.3\u00b0 \u2192 self-locking with 0.4\u00b0 margin at 80\u00b0C). This worked example illustrates why solar tracker self-locking must be verified at operating temperature, not assumed.<\/p>\n<\/div>\n

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Five Common Ratio Calculation Errors \u2014 With Corrections<\/h2>\n
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Error 1 \u2014 Counting worm thread turns instead of starts<\/p>\n

A worm with 5 visible thread turns (5 grooves along the shaft length) is not a 5-start worm \u2014 it is almost certainly a single-start worm 5 turns long. Count initiation points at the worm end face, not thread passes along the length. A single-start worm with 60 wheel teeth gives 60:1 ratio. A 5-start worm (5 initiation points at the end face) with 60 wheel teeth gives 12:1 ratio \u2014 a factor-of-5 error.<\/p>\n<\/div>\n

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Error 2 \u2014 Using transmission ratio and reduction ratio interchangeably without sign<\/p>\n

A worm gear set is a reduction drive \u2014 40:1 means 40 input revolutions produce one output revolution. The motor always drives the worm; the worm always drives the wheel. There is no ambiguity about direction in standard operation. However, when discussing overall system ratios in documentation, always state “40:1 reduction” or “output speed = input speed \u00f7 40” explicitly to avoid the error of a reader treating it as an amplification ratio.<\/p>\n<\/div>\n

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Error 3 \u2014 Using efficiency \u03b7 = 1.0 when calculating required motor torque<\/p>\n

Required input torque = required output torque \u00f7 (ratio \u00d7 efficiency). Omitting efficiency (using \u03b7 = 1.0) understates the required input torque by 15\u201340% depending on the ratio. At 40:1 with \u03b7 = 0.78, the input torque requirement is 28% higher than the \u03b7 = 1.0 estimate. Motor selected on an \u03b7 = 1.0 basis will be undersized, run above rated torque, trip on overcurrent protection, or fail on thermal overload within months.<\/p>\n<\/div>\n

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Error 4 \u2014 Assuming self-locking for any ratio without checking at operating temperature<\/p>\n

As shown in the worked example above, self-locking depends on lead angle relative to friction angle at the operating temperature with the specified lubricant. A drive that self-locks at 20\u00b0C with mineral oil may not self-lock at 75\u00b0C with synthetic oil on a solar tracker. Always verify at the maximum operating temperature with the specified lubricant \u2014 not at catalog ambient conditions with a generic friction coefficient.<\/p>\n<\/div>\n

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Error 5 \u2014 Specifying a non-integer ratio that requires non-standard tooth counts<\/p>\n

Since i = z2 \u00f7 z1 and z1 is an integer (1, 2, 3…), the gear ratio i must be an integer multiple of z1 divided by any integer z2. A ratio of 33.3:1 cannot be achieved with a single-start worm (would need z2 = 33.3, which is not an integer). It can be achieved with a 3-start worm and z2 = 100 (100 \u00f7 3 = 33.3:1) \u2014 but this is not self-locking and requires a non-standard tooth count. For non-integer target ratios, always check whether a multi-stage arrangement with standard tooth counts is more practical than a single-stage non-standard design.<\/p>\n<\/div>\n<\/div>\n

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\"worm<\/div>\n

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Standard Ratio Quick Reference \u2014 Preferred Tooth Count Combinations<\/h2>\n

Standard ratios correspond to tooth count combinations that avoid poor tooth geometry (too few wheel teeth causing undercutting, or very high wheel tooth counts requiring large and expensive wheels). The table below lists the most frequently specified ratios in Korea Ever-Power’s production range:<\/p>\n

\n\n\n\n\n\n\n\n\n\n\n\n\n\n
Forhold<\/th>\nz1 (starts)<\/th>\nz2 (wheel teeth)<\/th>\nSelf-Locking<\/th>\nTypisk anvendelse<\/th>\n<\/tr>\n<\/thead>\n
7.5:1<\/td>\n2<\/td>\n15<\/td>\nIngen<\/td>\nHigh-efficiency low-ratio worm stage<\/td>\n<\/tr>\n
10:1<\/td>\n1<\/td>\n10<\/td>\nMarginal<\/td>\nLight-duty actuator, verify self-locking requirement<\/td>\n<\/tr>\n
15:1<\/td>\n1<\/td>\n15<\/td>\nYes (borderline)<\/td>\nPackaging machine, conveyor corner drive<\/td>\n<\/tr>\n
20:1<\/td>\n1<\/td>\n20<\/td>\nYes<\/td>\nAgricultural implement drive, general industrial<\/td>\n<\/tr>\n
30:1<\/td>\n1<\/td>\n30<\/td>\nYes<\/td>\nManual hoist, transplanter row adjustment<\/td>\n<\/tr>\n
40:1<\/td>\n1<\/td>\n40<\/td>\nYes<\/td>\nCNC 4th-axis table, industrial conveyor<\/td>\n<\/tr>\n
60:1<\/td>\n1<\/td>\n60<\/td>\nYes<\/td>\nSolar tracker single-axis, precision positioning<\/td>\n<\/tr>\n
80:1<\/td>\n1<\/td>\n80<\/td>\nYes<\/td>\nSolar tracker, medical positioning<\/td>\n<\/tr>\n
100:1<\/td>\n1<\/td>\n100<\/td>\nYes<\/td>\nSlow-speed heavy machinery, valve drives<\/td>\n<\/tr>\n<\/tbody>\n<\/table>\n<\/div>\n

Korea Ever-Power manufactures all ratios in this table as standard catalog items in the M1 to M12 module range. Non-standard ratios requiring custom tooth counts are accepted \u2014 contact us<\/a> with the specific tooth count requirement and we will confirm whether dedicated hob procurement is necessary. For complete enclosed drive units at any of these standard ratios, snekkegearreduktionsgear<\/a> are available as sealed ready-to-mount units.<\/p>\n

\"snekkegearrelateret<\/p>\n

Ofte stillede sp\u00f8rgsm\u00e5l<\/h2>\n
\nI know my required output RPM and motor RPM. Is ratio = motor RPM \u00f7 output RPM always correct for a worm drive?<\/summary>\n
Yes, in standard worm drive operation where the worm is the driver and the wheel is the driven element. The reduction ratio i = input (worm) RPM \u00f7 output (wheel) RPM. This gives the required z2 \u00f7 z1 value. Round to the nearest integer combination \u2014 for example, a required ratio of 38.5:1 can be achieved as z2 = 77, z1 = 2 (two-start worm, 77-tooth wheel, exact 38.5:1) or approximately as z2 = 39, z1 = 1 (39:1, which gives output speed 2.5% slower than target \u2014 acceptable for most applications). The correct choice depends on whether the exact ratio is critical for indexing or timing purposes.<\/div>\n<\/details>\n
\nHow do I determine the output torque from a worm drive if I only know the motor rated torque?<\/summary>\n
Output torque = motor rated torque \u00d7 ratio \u00d7 efficiency. For example: motor rated torque 2.8 Nm, ratio 40:1, efficiency 0.78: output torque = 2.8 \u00d7 40 \u00d7 0.78 = 87.4 Nm. This is the continuous output torque available at rated motor load. For the peak torque available at motor stall (locked rotor), use motor stall torque (typically 2.5\u20133.5\u00d7 rated torque) in the same formula \u2014 but peak torque is limited to brief intervals and should not be used for sustained load calculations. The motor datasheet should provide both rated torque and stall torque as separate specifications.<\/div>\n<\/details>\n
\nCan I achieve any arbitrary ratio with a worm gear, or are there standard ratios I should use?<\/summary>\n
In principle, any integer multiple of the start count can be achieved by specifying the corresponding wheel tooth count. In practice, minimum and maximum practical tooth counts exist. The minimum wheel tooth count to avoid undercutting is approximately 17\u201320 teeth (below this, the wheel tooth root is cut away by the hobbing process). The maximum practical tooth count before the wheel becomes extremely large and expensive is approximately 100\u2013120 teeth for most applications. This gives a practical single-start worm ratio range of approximately 17:1 to 120:1. For ratios outside this range, two-stage arrangements or multi-start worms are used. Custom ratios (e.g., exactly 47:1) are producible \u2014 a 47-tooth single-start wheel is not a standard item but is manufacturable with standard tooling at a normal lead time.<\/div>\n<\/details>\n
\nHow does gear ratio affect the worm gear backlash in angular terms?<\/summary>\n
Backlash in a worm gear set is typically specified as a linear dimension at the worm wheel pitch circle (in millimeters). To convert to angular backlash at the output shaft: angular backlash (radians) = linear backlash (mm) \u00f7 pitch circle radius (mm). Convert to arc-minutes by multiplying radians by 3438. For a 60-tooth M4 wheel (pitch circle radius = 120 mm) with 0.08 mm backlash: angular backlash = 0.08 \u00f7 120 = 0.000667 radians = 2.3 arc-minutes. Higher ratios (more wheel teeth, larger pitch circle) mean the same linear backlash translates to smaller angular error at the output \u2014 which is one reason worm drives at high ratios can achieve usable positioning accuracy even with moderate linear backlash values.<\/div>\n<\/details>\n
\nMy required ratio is 66.7:1 \u2014 how do I specify this exactly?<\/summary>\n
66.7:1 = 200:3 exactly. This requires z1 = 3 starts on the worm and z2 = 200 teeth on the wheel. A 200-tooth wheel at any practical module will be very large and expensive. The more practical approach: ask whether 66.7:1 is truly necessary. For most position control applications, 65:1 (z1=1, z2=65) or 67:1 (z1=1, z2=67) would give an output speed within 2.6% of target \u2014 usually acceptable in open-loop positioning by adjusting the number of motor steps. If the exact ratio is needed (for example, to achieve an exact relationship between motor encoder pulses and output angle), contact us to discuss the two-stage option: a first stage at 6.67:1 with a second stage at 10:1, both achievable with standard tooth counts and a compact stacked arrangement.<\/div>\n<\/details>\n
\nWhen I look at a worm shaft, I count 8 threads on its surface. Does that mean it’s an 8-start worm?<\/summary>\n
Almost certainly not. What you are counting are the thread turns \u2014 the number of times the thread wraps around the cylinder along the worm’s length. A single-start worm with 8 thread turns is still z1 = 1. The correct way to determine start count is to look at the end face of the worm shaft (the flat face at either end) and count the number of thread initiation points visible there \u2014 each one is a separate start. One groove visible at the end face = single-start. Two grooves spaced 180\u00b0 apart = two-start. The thread turn count along the shaft length is related to the worm length and lead angle, not to the start count that determines the gear ratio.<\/div>\n<\/details>\n
\nWhat information should I provide to Korea Ever-Power to get a correct worm gear quote?<\/summary>\n
The minimum information for a quotation: (1) required gear ratio; (2) worm shaft input speed in RPM; (3) required output torque in Nm (or output power in kW and output speed in RPM \u2014 we can derive torque from these); (4) whether self-locking is required; (5) shaft layout (right-angle standard, or other); (6) bore diameter for the wheel, and whether keyway is needed; (7) operating environment (indoor, outdoor coastal, chemical contact) for material selection. With these seven parameters, we can provide a module recommendation, material specification, precision class, and confirmed price within one working day. Missing any of the first three items means we will ask before quoting \u2014 sending all seven up front saves a round trip.<\/div>\n<\/details>\n

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Have Your Ratio Calculation Verified \u2014 Then Get a Quote<\/h2>\n

Send your required ratio, output torque, input speed, and whether self-locking is needed. Our engineering team will confirm the correct z1\/z2 combination, efficiency estimate, and motor sizing implications \u2014 then provide a specification and price within one working day.<\/p>\n

Submit Your Ratio for Verification<\/a>
\nGennemse snekkegearprodukter<\/a><\/div>\n<\/div>\n<\/div>\n

Redakt\u00f8r: Cxm<\/p>\n<\/div>\n

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  How to Calculate Worm Gear Ratio \u2014 Engineering Guide with Worked Examples Getting the gear ratio wrong in a worm drive specification wastes more money than the gear set itself \u2014 wrong output speed means wrong motor selection, wrong torque means undersized components, and wrong self-locking assumption means a brake retrofit. This guide walks […]<\/p>","protected":false},"author":1,"featured_media":0,"comment_status":"closed","ping_status":"closed","sticky":false,"template":"","format":"standard","meta":{"_et_pb_use_builder":"","_et_pb_old_content":"","_et_gb_content_width":"","footnotes":""},"categories":[4774],"tags":[],"class_list":["post-1820","post","type-post","status-publish","format-standard","hentry","category-worm-gear"],"_links":{"self":[{"href":"https:\/\/wormwheelgear.top\/da\/wp-json\/wp\/v2\/posts\/1820","targetHints":{"allow":["GET"]}}],"collection":[{"href":"https:\/\/wormwheelgear.top\/da\/wp-json\/wp\/v2\/posts"}],"about":[{"href":"https:\/\/wormwheelgear.top\/da\/wp-json\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"https:\/\/wormwheelgear.top\/da\/wp-json\/wp\/v2\/users\/1"}],"replies":[{"embeddable":true,"href":"https:\/\/wormwheelgear.top\/da\/wp-json\/wp\/v2\/comments?post=1820"}],"version-history":[{"count":4,"href":"https:\/\/wormwheelgear.top\/da\/wp-json\/wp\/v2\/posts\/1820\/revisions"}],"predecessor-version":[{"id":1825,"href":"https:\/\/wormwheelgear.top\/da\/wp-json\/wp\/v2\/posts\/1820\/revisions\/1825"}],"wp:attachment":[{"href":"https:\/\/wormwheelgear.top\/da\/wp-json\/wp\/v2\/media?parent=1820"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/wormwheelgear.top\/da\/wp-json\/wp\/v2\/categories?post=1820"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/wormwheelgear.top\/da\/wp-json\/wp\/v2\/tags?post=1820"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}