MechMaxx BX42S 4-inch PTO Woodchipper Review (2026): 4-inch PTO Woodchipper
MechMaxx's sole PTO attachment — a 3-point-hitch 4-inch chipper for subcompact and compact tractors.
MechMaxx 3 Point Wood Chipper Attachment For Tractors BX42S Assembly Video
Manufacturer assembly and walkaround of the BX42S 3-point PTO chipper attachment, covering the Cat-1 hitch and driveline.
- Fits a wide tractor HP range
- Low-cost entry to PTO chipping
- Compact for storage
- 4-inch limit — Woodmaxx's entry PTO units chip larger material
- Shorter warranty than Woodmaxx PTO line
MechMaxx BX42S 4-inch PTO Woodchipper specs at a glance
- Brand
- MechMaxx
- Model
- BX42S
- Power type
- pto
- Max branch diameter
- 4"
- Power
- PTO-driven, 18–45 HP tractor
- Feed system
- Manual
- Weight
- 340 lb
- Price (MSRP)
- $1,399
- Warranty
- 1 year
Will the BX42S fit my tractor?
The MechMaxx BX42S 4-inch PTO Woodchipper needs 18–45 PTO HP. Here’s how 26 common compact and utility tractors match up — rated PTO HP, not engine HP (after typical 10–15% drivetrain losses).
| Tractor | Engine HP | PTO HP | Hitch | BX42S verdict |
|---|---|---|---|---|
| Kubota BX23S | 22 | 15 | Cat 1 | Too small |
| Kubota LX2610 | 25 | 19 | Cat 1 | Fits |
| Kubota L2501 | 24 | 19 | Cat 1 | Fits |
| Kubota L3301 | 33 | 26 | Cat 1 | Fits |
| Kubota L3901 | 37 | 30 | Cat 1 | Fits |
| Kubota L4701 | 47 | 38 | Cat 1 | Fits |
| Kubota MX5400 | 55 | 45 | Cat 2 | Fits |
| Kubota M4-071 | 70 | 58 | Cat 2 | Oversized |
| John Deere 1025R | 24 | 18 | Cat 1 | Fits |
| John Deere 2025R | 25 | 19 | Cat 1 | Fits |
| John Deere 3025E | 24.7 | 19 | Cat 1 | Fits |
| John Deere 3032E | 32 | 25 | Cat 1 | Fits |
| John Deere 3039R | 38.2 | 30 | Cat 1 | Fits |
| John Deere 3046R | 45.3 | 37 | Cat 1 | Fits |
| John Deere 4044M | 43.1 | 35 | Cat 1 | Fits |
| John Deere 4066R | 65.9 | 53 | Cat 2 | Oversized |
| Mahindra 1533 | 33 | 26 | Cat 1 | Fits |
| Mahindra 2638 HST | 37.4 | 29 | Cat 1 | Fits |
| Massey Ferguson 1735M | 35 | 28 | Cat 1 | Fits |
| Massey Ferguson 2705E | 49 | 40 | Cat 2 | Fits |
| New Holland WORKMASTER 25S | 24.7 | 18 | Cat 1 | Fits |
| New Holland WORKMASTER 35 | 35 | 28 | Cat 1 | Fits |
| Kioti CK2620 | 24.5 | 20 | Cat 1 | Fits |
| Kioti NX4510 | 45 | 38 | Cat 1 | Fits |
| LS MT225S | 24.4 | 18 | Cat 1 | Fits |
| LS MT342 | 41.3 | 32 | Cat 1 | Fits |
“Fits” = within the manufacturer’s rated PTO HP range. “At limit” = below the minimum by 5–15%, will feel underpowered on seasoned hardwood. “Too small” = undersized for reliable chipping. “Oversized” = above range (works but overkill).
Who should buy the BX42S — and who should skip it
- You own a tractor with 18–45 PTO HP and a Category 1 three-point hitch.
- Your typical branches are 2–4 inches in diameter.
- You want a capable chipper under $2k without stepping up to commercial-grade pricing.
- You don't own a tractor. A gas-standalone chipper of comparable capacity is the right category for you.
- Your branches regularly exceed 4 inches. Step up to a 6-inch-capacity chipper — forcing this unit at the limit bogs the feed and accelerates blade wear.
- You plan to put the chipper through commercial-scale hours (50+ per year). Look for a model with a longer warranty — wearing parts and bearings are the typical failure points.
BX42Sblade replacement & sharpening
Two reversible flywheel knives — on a PTO chipper, always disengage the PTO and let the flywheel stop fully (60+ seconds) before opening the hood.
Parts availability on the BX42S is the weakest in the MechMaxx line; measure your blade and order generic blanks if factory stock is backordered.
- Blade count
- 2 flywheel knives
- Bed knife
- Yes — fixed anvil
- Sharpening angle
- 35–40°
- Reversible
- Yes — doubles edge life
- Blade material
- Hardened alloy steel
- Replacement set
- $80–$130
- Sharpening interval
- 20–30 hours
- Bolt torque
- 45–55 ft-lb
- 01Stop the machine and isolate power
Disengage the PTO, shut the tractor off, and remove the key. Wait 60+ seconds for the BX42S flywheel to stop completely — it coasts longer than the engine.
- 02Open the discharge or flywheel access cover
Remove the bolts on the BX42S flywheel access hood (or flip the hinged hood if equipped). Swing it clear so you have line-of-sight to every blade position.
- 03Rotate the flywheel to the first blade
Turn the flywheel by hand until the first of the 2 knives is aligned with the access opening. Mark it "1" with a paint pen so you can keep track of orientation.
- 04Break the blade bolts loose
Use a breaker bar on each of the 2 blade bolts. Woodmaxx and Woodland Mills both thread-lock these at the factory; heat gently if they don't yield. Do not pry on the flywheel itself.
- 05Slide the blade out and inspect
Remove the blade and inspect for cracks, nicks deeper than 1/16", and rounded bevels. A cracked blade goes straight in the scrap bin — never re-sharpened.
- 06Flip or replace the blade
The BX42S uses 2 reversible knives. If the secondary edge is still clean, simply flip the blade for a fresh edge. If both edges are worn, sharpen at 35–40° on a belt sander — quench every 10–15 seconds to avoid bluing the Hardened alloy steel.
- 07Balance the set
Remove equal material from every blade in the set. On the BX42S's 2-knife flywheel, even a 1–2 gram imbalance shows up as vibration at operating RPM. Weigh on a gram scale after sharpening.
- 08Reinstall and torque
Apply anti-seize to the bolt threads (not the heads) and torque in a star pattern to 45–55 ft-lb. Use fresh lock washers — reused washers are the #1 cause of a loose blade downstream.
- 09Repeat for every remaining blade
Rotate the flywheel and repeat steps 3–8 for the remaining 1 knives. Then inspect the fixed bed knife — if the edge is rounded, flip or replace it and reset the blade-to-anvil gap to ~0.030" with feeler gauges.
- 10Close up and test-run
Rotate the flywheel by hand one full revolution to confirm no contact with the bed knife or housing. Close the access cover. Start the tractor, engage PTO at low idle, and listen for 30 seconds before ramping to operating RPM. Feed one small test branch before returning to normal work.
BX42S — frequently asked questions
- How much tractor HP do I need for the BX42S?
- The MechMaxx BX42S 4-inch PTO Woodchipper is rated for 18–45 PTO HP. That's tractor PTO horsepower after drivetrain losses — rated engine HP is typically 10–15% higher. A 21 HP engine tractor produces roughly 18 PTO HP and would run this chipper at the minimum. The comfortable working range is 23–41 PTO HP.
- Does the BX42S fit a Category 1 three-point hitch?
- Yes. The BX42S mounts to a standard Category 1 three-point hitch and accepts a 540 RPM rear PTO shaft (included). Quick hitch compatibility varies by brand — most John Deere iMatch and Pat's Easy Change hitches accept it with a standard top-link bushing.
- What's the maximum branch diameter the BX42S can chip?
- The MechMaxx BX42S 4-inch PTO Woodchipper is rated for branches up to 4 inches in diameter. Green and softwood branches chip reliably at the rated maximum. Seasoned hardwood at the maximum slows the feed rate and bogs the flywheel more — plan for 3-inch hardwood as your comfortable working size.
- What's the warranty on the BX42S?
- MechMaxx covers the BX42S with a 1-year warranty. Wearing parts (blades, belts) are excluded under normal use; commercial-scale use may require the manufacturer's commercial warranty tier.
- How much does the BX42S weigh?
- The MechMaxx BX42S 4-inch PTO Woodchipper weighs approximately 340 lb. Check your tractor's three-point hitch lift capacity before purchase — a Category 1 tractor typically lifts 1,200–1,800 lb at the hitch pins; Category 2 lifts 2,500+ lb.
- How often do the blades on the BX42S need sharpening?
- For typical property use (20–40 hours per year), sharpen the BX42S's blades once per season. Heavy hardwood use cuts that to every 15–20 hours. A full replacement set runs roughly $80–$250 depending on blade count and material. See our woodchipper blade sharpening guide for the full process.
- Where is the BX42S made?
- MechMaxx chippers are assembled with globally sourced components. The chipper frame, feed system, and flywheel are imported. MechMaxx distributes from a US warehouse.