Mechanical

Shaft support: set the axis height, print the bore support free

This page opens the DrawSTL shaft support template: a parametric bearing block that screws down through its base while a shaft passes through its upright body, sized in millimetres and downloaded as a print-ready STL. You set the bore and the height of the shaft axis above the bed, and the body height, wall and arched top follow from that.

The top of the bore is built as a 45 degree teardrop, so even a horizontal hole prints without supports. The 45 degree ribs on both sides reduce how much the block flexes under side load, and base screw holes are placed automatically to clear both body and ribs.

Open in editor See the sizes

Free, no sign-up. Change the sizes in millimetres and download the STL.

Ready-made variants

Each variant is the same template with different settings. Follow the link and the editor opens with those values.

Small support for an 8 mm shaft

Base width: 50 mm · Base depth: 30 mm · Base thickness: 3 mm +8
Open this variant: Small support for an 8 mm shaft
Standard support for a 20 mm shaft

Base width: 124 mm · Base depth: 49 mm · Base thickness: 4 mm +7
Open this variant: Standard support for a 20 mm shaft
Tall pillow block for a 25 mm shaft

Base width: 120 mm · Base depth: 60 mm · Base thickness: 5 mm +8
Open this variant: Tall pillow block for a 25 mm shaft
Plain support without ribs, 12 mm shaft

Base width: 80 mm · Base depth: 40 mm · Base thickness: 4 mm +7
Open this variant: Plain support without ribs, 12 mm shaft

Adjustable sizes

These values are edited in the editor's template panel. A number outside the range is clamped to the nearest limit automatically.

Size	Range	Default
Dimensions
Base width	20–160 mm	124 mm
Base depth	15–120 mm	49 mm
Base thickness	2–25 mm	4 mm
Corner radius	0–25 mm	4 mm
Body
Body width	12–120 mm	70 mm
Body height	15–140 mm	50 mm
Body thickness	4–60 mm	8 mm
Shaft diameter	3–80 mm	20 mm
Shaft axis height	8–120 mm	28.5 mm
Wall around shaft	2–25 mm	2 mm
Rib length	0–60 mm	60 mm
Mounting
Screw hole	0–14 mm	6 mm

What it is used for

End support for linear rails, lead screws and plain shafts
Axis mounting in CNC, laser and 3D printer builds
Homemade winding and rotary table mechanisms
Anchoring lever, drum and pulley axles to a bench
The rotation axis for tape, roll and filament spools

Printing tips

Orientation: The base prints on the bed with the body pointing up. The bore stays horizontal, and its 45 degree teardrop top means no supports are needed.
Layer height: 0.2 mm. Use 0.16 mm when bore accuracy matters more than speed.
Infill: 60% and up for load-bearing supports, solid in critical spots. Keep at least 4 walls.
Supports: None. The teardrop bore, the arched top and the 45 degree ribs are all built to print support free.
Material: PETG is tougher than PLA under shaft load and vibration. Use ASA for heat exposure, and fit a separate nylon bushing inside the bore for a real sliding surface.

Tips

For a rotating shaft, make the bore 0.3 mm over size; the teardrop flattens the top so the shaft contacts on the sides.
For a static shaft, 0.1 mm over is enough, and you can add a side hole in the editor for a clamping screw.
Use wide washers when tightening the base screws so they do not crush the plastic.

Axis height, body height and wall

Axis height is the distance from the mounting surface to the shaft centre, and it is the defining dimension because everything else in the assembly aligns to it. Body height includes the material above the shaft, so it is always larger than the axis height.

The template checks that relation and raises the body automatically when your value leaves too little material above the bore. A 2 mm wall around the shaft is fine for light loads, while 4 to 6 mm makes a clear difference under real load.

Axis height: the master dimension that sets assembly alignment
Body height: must leave material above the bore
2 mm wall around the shaft for light loads, 4-6 mm for load-bearing
Rib length: matters more as the axis height grows

Ribs and base hole placement

A shaft mostly pushes sideways and downwards. The upright body handles downward load easily, but side load tries to bend it fore and aft at the joint with the base, and the 45 degree triangular ribs work against exactly that.

Base screw holes are positioned by searching for a spot that clears the body and the ribs while staying inside the base edge. If no position satisfies all of that, no holes are cut; widening the base, shortening the ribs or reducing the hole diameter fixes it.

Frequently asked questions

The bore is horizontal, does it really print without supports?

It does. The top of the bore is built as a 45 degree teardrop, so there is nothing to bridge and the hole comes out clean.

Why did my body height change?

If too little material would remain above the bore, the body is raised automatically. The panel shows the new value it used.

Why were no base holes cut?

No position was found that clears the body, the ribs and the base edge at once. Enlarge the base, shorten the ribs or reduce the hole diameter.

Can I fit a ball bearing in the bore?

The bore is a plain cylinder with no bearing seat step. Enter the bearing outer diameter as the bore and adjust the seat depth in the editor.

How do I align two supports?

Print two copies with the same axis height and screw both to the same surface. Since axis height is measured from the mounting face, alignment follows directly.

Similar templates

Set the sizes to fit your part

Open the template in the editor, enter your values and download a print-ready STL. No account needed.

Open in editor

Ready-made variants

Small support for an 8 mm shaft

Standard support for a 20 mm shaft

Tall pillow block for a 25 mm shaft

Plain support without ribs, 12 mm shaft