Threaded rod
Vitamin
| Threaded metal rod, used as lead screws and for the frame. | |
| Wikipedia | none |
A threaded rod (aka allthread, studding, and in Australia, Booker Rod ) is a metal rod with threads welded on or rolled out. It is usually used as a frame construction part and as lead screws for the Z-axis. The most commonly used type of threaded rod in a RepRap or a RepStrap is a steel M8 (8 mm diameter) one.
Contents
Leadscrews
Leadscrews are threaded rods used to lead a component on, for example the X-axis assembly on the Z-axis. For most RepRaps a common (straight!) threaded rod is sufficient, but for higher precision and reduced wobble you might want to use real leadscrews.
There are two main thread profiles for leadscrews, both of which are trapezoidal: Trapezoidal and Acme. The important but subtle difference is the angle of the thread flank. Be sure to get matching nuts.
Insights Regarding Leadscrew Usage For Fast Axes
- Take steps to avoid entire lead screw moving in end-to-end direction
- If you're unsure about required torque, see Oriental Motors' sizing tools
- Lead screw and nut must be fixed in aligned position, (relative) twist will bind up the nut
Preloading
A common problem when using leadscrews (also for common thread rod ones) is backlash. Because the nut has to be able to rotate freely around the rod, its threading is ever so slightly wider than the rods. Even when the rod is not turning, the nut can move a tiny bit up and down, which is the backlash. Reducing this improves the accuracy of the machine.
A common way to reduce leadscrew backlash is to preload: ensure the nut is in contact with the thread at all times. You can do this using two nuts with a spring in between. This keeps each nut pressed against the thread, reducing backlash. However, it will also make the rod harder to turn. More information and pictures in the article Backlash in Lead Screws: What It is and What to do About It.
Vendors
Threaded Rods
The following table lists Threaded Rods vendors:
| Vendor | Loc. | Product | Diameter | Length | Additional notes | |
|---|---|---|---|---|---|---|
| Folger Technologies, LLC | US | Threaded Rod | M5, M6, M8, M10... | 1000mm/custom cuts | Ships Worldwide | |
| 3D Acessories Hub | IN | threaded rod | 5mm & 8mm" | 1000mm | ||
| Alfa-Tech3D | DK | Threaded rod | M2 , M3, M4, M5, M6, M8 & M8x1, M10 | 200-800mm | Shipping worldwide | |
| Grainger | US | threaded rod | M5, M8, & M10 | 1000mm | sold in packs of 25 | |
| MSC Industrial Suply Co | US | threaded rod | M5, M8, & M10 | 1000mm | Oil finish or Zinc plated | |
| McMaster-Carr | US | threaded rod | M5, M8, M10, ... | ... | Lots of sizes and choices. Ships to US only | |
| DIY-India.com | IN | Threaded rod | M5, M8, M10, ... | ... | Lots of sizes and choices. Ships to India only | |
| Makemendel | IN | Threaded Rod | M5, M8, M10, ... | ... | Lots of sizes and choices. Ships to Worldwide |
Leadscrew
The following table lists Trapezoid and Acme leadscrew vendors:
| Vendor | Loc. | Product | Diameter | Length | Pitch | Additional notes |
|---|---|---|---|---|---|---|
| Alfa-Tech3D | DK | Trapezoidal Threaded | 8 mm | 300mm, 500mm | 2 mm | Shipping worldwide. |
| Enco | US | Imperial Acme threaded rod | 1/4 - 5/8" | 6' | 8-16 TPI | |
| HPC Europe | FR/IT | Trapezoidal rolled leadscrew | 10-120 mm | 1000-3000 mm | 2-16 mm | |
| RobotDigg | CN | Acme Threaded Rod Nema17 | 8mm | 280 or 350 mm | 2 mm | |
| Roton | US | Metric threaded rod | 10-28 mm | 6-144" (152-3658 mm) | 2-8 mm | |
| Makemendel | IN | ACME Threaded Rod with Nut | 10 mm | 255mm | 3 mm | custom length Threaded rod is also available.; |
| TaoTac.com | VN | ACME Threaded Rod with Nut | 8 mm | 300 mm | 3 mm |
Leadscrew nuts
The following table lists Trapezoid and Acme leadscrew nut vendors.
| Vendor | Loc. | Product | Diameter | Pitch | Smallest outer diameter | Additional notes |
|---|---|---|---|---|---|---|
| Alfa-Tech3D | DK | Brass Nut & Anti Backlash nut | 8 mm | 2 mm | Shipping worldwide. | |
| Enco | US | Imperial Acme round nuts | .25 - 2.5" | 4 - 16 TPI | 0.68-7.5" | |
| HPC Europe | FR/IT | Trapezoidal nut | 10-60 mm | 2-9 mm | 17-90 mm | |
| RobotDigg | CN | Anti-backlash Nut | 8 mm | 2 mm | ||
| Roton | US | Imperial Acme nuts | .1875 - 3.5" | 2-20 TPI | .5" | |
| TaoTac.com | VN | Anti-backlash Nut | 8 mm | 2 mm |
External Links
- Z Motor setup with leadscrews on the forum
- Acme versus Threaded rod on the forum
- Alex English. "Accuracy vs precision and threaded rod vs leadscrews in 3d printers".
