T-Slot Nuts & Bolts for Aluminum Extrusion
T-slot nuts are nuts shaped to slide or drop into the slot of an aluminum extrusion and lock against the slot’s lips when you tighten a bolt. They let you attach brackets, panels and other profiles anywhere along a frame. The one rule: the nut must match the profile’s slot width, and the bolt must match the nut’s thread.
Which nut fits which profile
| Profile | Slot width | Nut threads available | Bolt we specify for frame joints | Source |
|---|---|---|---|---|
| 3030 | 8 mm | M3, M4, M5, M6 | M6 × 12 mm per bracket bolt (HBLFSN6) | MISUMI HNTU6 |
| 4040 | 10 mm | M3, M4, M5, M6, M8 | M8 × 20 mm per bracket bolt (HBLFSN8) | MISUMI HNTP8 |
| 2020 | 6 mm | M3, M4, M5 | M5 × 10 mm per bracket bolt (HBLFSN5) | MISUMI HFS5-2020 |
Three types of T-slot nut
| Type | How it goes in | When to use it |
|---|---|---|
| Drop-in (post-assembly) spring nut | Pushed into the slot from the face, any time, even after the frame is built | Adding a shelf, panel or hook to a finished frame |
| Slide-in (pre-assembly) nut | Slid in from the end of the profile before that end is closed off | Main frame joints you plan during the build |
| Spring-loaded slide-in nut | Slid in from the end; a spring or ball holds it in place so it doesn't fall when the profile is vertical | Vertical legs and posts |
Type definitions follow MISUMI’s catalog: post-assembly nuts “can be installed through the groove after the aluminum frame has been assembled” (MISUMI HNTP8). Pre-assembly nuts go in “from the groove end face before assembly” (MISUMI HNTU6).
Plan the slide-in nuts before you close the frame. Once both ends of a profile are joined, the only way to add a nut is a drop-in type. Our parts lists count every nut per profile, and the step-by-step instructions tell you when to insert them.
Bolts
Two head styles cover most furniture builds:
- Button head: low, rounded head; the usual choice for brackets.
- Flat head (countersunk): sits flush in countersunk holes, for panels and tops.
Bolt length = thickness of the part you’re clamping + enough thread to fully engage the nut, without bottoming out in the slot. For our bracket joints we use MISUMI’s listed lengths: M5 × 10 mm for 2020, M6 × 12 mm for 3030 and M8 × 20 mm for 4040.
Buying T-slot nuts
Every Slot & Shaft parts list gives the exact nut type, thread and quantity for your design, and links each line to a US seller. We don’t show prices; check the seller’s page.
Want everything counted, bagged and pre-cut? Buy as a pre-cut kit — join the waitlist.
Related
FAQ
How do I know which T-slot nut I need?
Match two things: the slot width of your profile (e.g. 8 mm for our 3030, 10 mm for our 4040) and the bolt thread (e.g. M6 or M8). The profile’s size name alone isn’t enough, because two “4040” profiles can have different slots.
Can I add T-slot nuts after the frame is assembled?
Yes. Use drop-in (post-assembly) nuts, which go in through the slot opening instead of the profile end (MISUMI).
What is the difference between a T-slot nut and a T-bolt?
A T-slot nut sits in the slot and takes a separate bolt. A T-bolt (slotted T-bolt) has the T-shaped head built in and takes a regular nut on the outside.
Why do my T-slot nuts fall down inside vertical profiles?
Plain slide-in nuts move freely. Spring-loaded nuts have a spring or ball that holds them in place, so they stay where you put them in a vertical leg (MISUMI).
How many T-slot nuts do I need?
One per bolt. A single-slot 90° bracket like MISUMI’s HBLFSN8 uses two bolts and two nuts (MISUMI). Don’t count by hand: open a project and the parts list counts every nut for your exact size.