The Proxxon IBS/E and FBS 115/E are the two flagship handheld rotary tools in the Proxxon Micromot range. Both run at 100W, both cover 5,000–20,000 RPM, and both accept the full range of Micromot accessories. The difference comes down to one thing: how they hold bits. That single difference has downstream implications for precision, convenience, and what accessories you need. Here’s how to choose.
At a Glance
| IBS/E (No. 38481) | FBS 115/E (No. 38472) | |
|---|---|---|
| Chuck system | Collet (precision) | Keyless chuck |
| Shank capacity | 6 fixed collet sizes | 0.3–3.2mm continuous |
| Bit changes | Collet wrench required | Tool-free, hand-tightened |
| Runout / concentricity | Lower runout (higher precision) | Slightly higher runout |
| Included accessories | 6 collets + 34 bits & cutters | Keyless chuck only |
| Best for | Extended precision work, engraving, milling | Varied tasks, frequent bit changes |
| Price | Higher (includes full accessory kit) | Lower entry price |
The Chuck System — The Key Difference
IBS/E — Collet System
The IBS/E uses precision steel collets that grip the bit shank concentrically — the collet compresses evenly around the shank when the clamping nut is tightened, centering the bit with minimal runout. This is the same principle used in professional CNC machines and milling centers. Lower runout means less vibration, cleaner cuts, and longer bit life — especially important for fine engraving, PCB milling, and extended grinding sessions where bit wobble compounds over time.
The trade-off: bit changes require loosening the clamping nut with a wrench, swapping the collet if the shank size changes, and re-tightening. Slower than a keyless chuck, but more precise.
The IBS/E comes with 6 collets (covering 1.0, 1.5, 2.0, 2.35, 3.0, and 3.2mm shanks) plus 34 industrial bits and cutters — making it a complete system out of the box.
FBS 115/E — Keyless Chuck
The FBS 115/E uses an integrated keyless chuck that accepts any shank from 0.3 to 3.2mm — tighten by hand, no wrench needed. Bit changes take seconds. This makes the FBS 115/E the better choice when you’re working across multiple bit types in a single session — switching between a drill bit, a grinding stone, and a polishing disc without stopping to swap collets.
The keyless chuck has slightly higher runout than a precision collet at the same shank size, but for most hobby, model-making, and general workshop applications the difference is imperceptible. Where it matters is in extended fine engraving or PCB trace milling where the IBS/E’s collet precision becomes a real advantage.
Included Accessories
This is where the IBS/E pulls significantly ahead on value:
- IBS/E — includes 6 precision collets (1.0–3.2mm), 1 clamping nut, and 34 industrial bits and cutters covering grinding stones, cutting discs, polishing discs, felt bobs, wire brushes, and more. Ready to use across all Micromot applications immediately.
- FBS 115/E — includes the keyless chuck only. Bits and accessories purchased separately.
If you’re starting from scratch, the IBS/E’s included kit represents significant value. If you already have a Micromot bit collection, the FBS 115/E’s lower entry price makes more sense.
Which Should You Choose?
Choose the IBS/E if you:
- Are buying your first Micromot tool and want a complete kit
- Do extended engraving, fine milling, or PCB work where precision matters
- Work primarily with one or two bit types per session
- Want the lowest runout for grinding and polishing applications
- Use TC burrs (3.2mm shank) — the included 3.2mm collet is essential
Choose the FBS 115/E if you:
- Already have a Micromot bit collection
- Switch between many different bit types in a single session
- Want the fastest possible bit changes
- Work across a wide range of shank sizes without wanting to manage collets
- Prefer a lower entry price and will build your accessory kit over time
Compatible Attachments — Both Tools
Both the IBS/E and FBS 115/E share the same 20mm collar diameter and are compatible with the full range of Proxxon Micromot attachments:
- Drill Stand MB 200 (No. 28600) — converts either tool into a stationary precision drill press or grinder; tilting head for angled work
- MICROMOT Tool Clamp (No. 28410) — mounts either tool horizontally or at angle for routing, milling, and engraving setups
- Flexishaft 110/P (No. 28620) — triple ball-bearing flexible shaft with 6 collets; for reaching tight spaces with the IBS/E
- Flexishaft 110/BF (No. 28622) — keyless chuck flexible shaft; pairs naturally with the FBS 115/E for consistent tool-free operation
- Footswitch FS (No. 38700) — hands-free on/off for two-handed engraving and carving work with either tool
Expanding Your Bit Collection
- Modeler’s Set — 13-Piece (No. 28910) — cutting, milling, grinding & drilling bits for Micromot tools; ideal first expansion for FBS 115/E owners
- MICROMOT Steel Collet Set — 6-Piece (No. 28940) — replacement or expanded collet set for IBS/E; essential if you add TC burrs (3.2mm shank)
- MICROMOT Three-Jaw Keyless Chuck (No. 28941) — adds keyless chuck capability to the IBS/E for sessions where fast bit changes matter
Cutter Selection
Whichever tool you choose, the cutter selection process is the same. Read our Proxxon Micromot Cutter Guide — TV Steel vs. TC Burrs vs. TC Milling Cutters for a complete breakdown of which cutter family is right for your material.
Shop Both Tools
- Proxxon Professional Rotary Tool IBS/E (No. 38481) — collet system, 6 collets + 34 bits included
- Proxxon Precision Rotary Tool FBS 115/E (No. 38472) — keyless chuck, 0.3–3.2mm continuous shank range