The Mafell SG 400 Slot Mortising Attachment (Ref. No. 201000) converts the Mafell LS 103 Ec Chain Mortiser into a high-precision slot mortising system for heavy timber construction. Designed for creating deep slots in solid wood and laminated timber beams (glulam), this attachment enables woodworkers and timber framers to accurately prepare large structural workpieces for gusset plate connections and insertion of hidden metal connecting pieces.

By coordinating directly with the base machine, the SG 400 achieves a maximum horizontal mortising depth of up to 400 mm (15 3/4 in.) and vertical depth up to 300 mm (11 13/16 in.). A robust, torsion-free guide support stand and exact special chain guide maintain tracking throughout the entire cut length, preventing tool drift and ensuring consistent slot dimensions from start to finish. An integrated cutting depth stop and clear vertical edge-spacing scale facilitate repeatable, precise setups without manual trial and error.

For angled timber joinery, the entire unit tilts up to 45 degrees in either direction. Depending on the installed chain set, slot widths range from 6 mm to 17 mm (1/4 in. to 11/16 in.), delivering versatility across various steel connector plate thicknesses.

Features & Benefits

• Up to 400 mm Cut Depth: Allows deep slotting in large glulam workpieces for inserting heavy structural connectors.
• Torsion-Free Guide Support Stand: Maintains strict alignment and rigidity to produce precise, parallel slot walls.
• Integrated Depth Stop and Scale: Enables accurate cutting depth adjustments and vertical edge spacing for consistent repeat cuts.
• 45-Degree Tilt Adjustment: Tilts up to 45 degrees in either direction to support angled slotting in timber framing.
• Versatile Slot Width Capability: Accommodates chain sets for mortising widths from 6 mm to 17 mm (1/4 in. to 11/16 in.).
• Exact Chain Guide System: Keeps the chain strictly on track from start to finish, preventing drift during long cuts.

What's Included

• (1) Slot Mortising Attachment SG 400
• (1) Grease Gun (Ref. No. 076158)

The SG 400 slot mortising attachment requires the Mafell LS 103 Ec Chain Mortiser as its basic power unit (sold separately). Compatible chain sets, chain bars, and sprockets must be selected separately based on required slot width and depth.

Shipping: Beaver Industrial Supply offers free shipping on orders over $199, with the exception of Sawstop and Laguna, which require additional fees to be collected. Other exceptions apply as noted on product pages.

We reserve the right to determine the fastest and most cost-effective manner of transportation for all orders that qualify for free shipping. Our shipping carriers cannot deliver to PO box or U.S. military post office box addresses, such as APO and FPO, so we require a physical street address for delivery. We use USPS, which typically takes 2-8 days for delivery, depending on your location, for smaller items and UPS Ground for all other ground shipments under 150 pounds.

• Returns: We accept returns and exchanges for a fee up to 30 days in unopened, new, and unused condition in the original packaging. Exceptions apply.

Please note, NO REFUNDS will be given on any new, used, or damaged item if it is not returned in the original packaging, no matter what condition the packaging is in. If the item qualifies for free shipping, you will be charged the original shipping cost and are responsible for shipping the product back with the shipping carrier of your choice.

We must receive the item undamaged. We recommend you package it accordingly and purchase insurance for higher-priced items to ensure you receive the full refund minus any incurred fees as applicable. We reserve the right to refuse the return of accessories.

Because items are your responsibility until they reach us, we recommend that you send the parcel using a delivery service that insures you of the value of the goods. Return shipping is at the customer's cost. At Beaver Industrial Supply’s discretion, delivery charges can be refunded if the goods are defective.

Returns require a return authorization number. Please call customer service at 314-773-5999 or submit a customer service inquiry to start the exchange or return process and receive an authorization number.

Machinery too large for parcel shipment (palletized or crated) is only returnable if there is a material defect that cannot be resolved by replacing components.