Grizzly G0846 Horizontal Slot Mortiser A must-have for custom furniture builders, cabinetry builders or other woodworkers using mortise and tenon joinery. The Grizzly G0846 Horizontal Slot Mortiser incorporates a router mounted on its side with the workpiece clamped to a multi-axis sliding table. Use it to quickly cut mortises for traditional mortise. This shop made mortising jig was originally designed by Philip Morley. This jig is easy to make, easy to use and is the perfect DIY tool to make clean, precise and repeatable mortises every time. The Morley Mortiser. Mortising machine. The base pro-vides a mounting surface for a metal track that guides the sliding tables, see drawing. In addition, it serves as a foundation for a tall, vertical tower that houses the router carriage. The base starts out as a simple plywood frame. The front and back (A) of this frame are identical in size, see Fig.
Accurate, repeatable mortises are guaranteed with this sliding table.
When a project calls for a lot of mortises, nothing beats the power of a mortising machine. The only drawback to a mortiser is that repositioning the workpiece to drill the overlapping “holes” can be a hassle. This sliding X-Y auxiliary table makes mortising a breeze. First, the long, steel hold-down and toggle clamp anchor the workpiece. Then just turn a hand wheel to move the large table from front to back to accurately position the mortise. Finally, turn another hand wheel to move the table side-to-side. The end result is a clean, straight mortise. Best of all, it only takes some simple hardware to accomplish these tasks. And it all adds up to one shop accessory you’ll wonder how you ever got along without.
SELECT YOUR PLAN PACKAGE
- $12.95 Learn more
- Learn more
What You Get:
- 10 printable (digital) pages of step-by-step instructions
- 34 full-color photos and illustrations
- Shop-tested techniques ensure your success
- Materials list
- Retail sources for hardware and supplies
Note: After your purchase, you will receive an email containing a PDF attachment of your purchased plan, as well as instructions for logging in to download the plan and access any other associated files and videos, which will all be located on this page.
Project Supplies & Hardware
Similar Woodsmith Plans
Imperial Plans
The United States Customary System of Units (USCS or USC), more commonly referred to as the English or Imperial system, is the standard set of units for our plans. It uses inches and feet for measurement. This is the one you probably want if you are in the United States, and it is the one we have traditionally offered on this website.
Metric Plans
Slot Mortising Machine Plans Free Printable
The International System of Units (SI), more commonly referred to as the metric system, is the alternative set of units that we have available for some of our plans. It uses millimeters, centimeters, and meters for measurement. This is the one you probably want if you are outside the United States. These plans are provided by our business partner, Australian Woodsmith, and are based on the original Woodsmith plan. However, dimensions and other elements of the plan may vary between the metric and standard versions. Be sure to double-check the plan before building.
Premium Plans
All of the information that you need to build our plans can be found in the standard plan. However, if you want even more granular detail to make your job easier, you should consider our premium plans. These come with additional shop diagrams that we drew when creating the prototypes. Shop drawings are not available for every plan.
Example Preview
Affiliate Link
Since you are an affiliate, you can use this url to link people to this page and get credited for it:
If you want to use an image thumbnail link, you can copy and paste something like this into the source code of your page:
Affiliate link unavailable.
Introduction: Horizontal Slot Mortiser
Tech in wood joinery meets handcrafted design + build. The top part is a mortising unit, below is a micro-adjust created using traditional methods. The story follows. I purchased this Jessem Mortise Mill unit a few years back and although I managed to produce some loose tenon slots successfully, it was not easy to set up. I can’t recall the issues exactly, but it was frustrating at times. So recently found the unit buried under a secondary workbench and decided I would make an effort at getting it to work successfully.
I had always wanted a horizontal slot mortiser setup and thought why not set this up to create slots in the horizontal plane instead of the vertical plane. The unit was marketed to be installed vertically with board placement underneath. Notice the etchings on the Mortise Mill are upside down. I’m not sure if having boards hanging below the unit contributed to the issues I had at the time, but nonetheless I wanted to mount it so loose tenon slots were created horizontally. Today, I use this slot mortise extensively in my furniture studio at Pirollo Design. Woodworking courses, woodworking plans and classes also available through WoodSkills
Step 1: A Suitable Platform
These images show the unit assembled to a rolling cart before building the micro-adjust unit. It was critical to find a suitable platform, i.e. workbench surface to be able to mount it. A rolling cart in my workshop was ideal since I could wheel the unit away when not in use and the footprint of the Mortise Mill was not large. The rolling cart has large locking casters which do a good job of keeping the cart immobile. I installed it so the surface of the base plate was even with the surface of the cart, this took some time. Large enough 1/4-20 bolts were used to maintain rigidity and keep it from shifting.
Tested it afterwards and I was pleased with the results. The later addition of a L-shaped wood bracket to support stiles while they were being mortised worked well. The ends of rails to be mortised were easily supported by the wood surface of the rolling cart. Further testing with clamping of boards provided me with a repeatable setup. I liked the fact that I could permanently leave the Mortise Mill bolted to the rolling cart and continue to use the complete top surface of the rolling cart as before.
Step 2: Micro-Adjust
An issue that soon came up was the vertical adjustment of the mortise slots on a horizontally-oriented board. Since the Mortise Mill was installed horizontally with horizontal board placement instead of vertical, the slot location adjustment was not as smooth as I would like due to the weight of the sliding component of the unit. I decided to build a micro-adjust setup to alleviate the problem. This was performed using some scrap walnut and maple. As can be seen in the pic, it is all wood construction with a 1/2 inch lead screw and wood handle. The end of the lead screw has a custom cradle contoured to fit the bottom edge of the sliding part of the Mortise Mill. Now I could precisely dial-in slot placements!
Step 3: Horizontal Slot Mortiser
Since the micro-adjust is cantilevered off the vertical posts of the rolling cart, I beefed up the supports. It is probably over-engineered now. Things to watch are the exact placement of the tip of the lead screw over the center of the edge of the Mortise Mill for smooth operation. A large paddle switch for the built-in Mortise Mill dust collection was installed for convenient access. The end result is a functional horizontal slot mortiser that provides precise adjustment of the slots. The rolling cart top serves as an excellent support for boards as can be seen in the images. The other images demonstrate how accurate the slots are for loosed tenon installation.
I don't have a plan for this at this time as you would need to acquire the Jessem Mortise Mill for this particular setup. Other plans, woodworking courses and classes are available at: WoodSkills
1 Person Made This Project!
- woodskills made it!
Recommendations
Plywood Challenge
Plastic Contest
Battery Powered Contest