How do you go about cutting your tenons?  Some shops try to make due with a hand saw.  Other shops invest hundreds of thousands of dollars into automated CNC machines.  The rest of us are somewhere in the middle:  carpenters who prefer to take the tool to the timber, and who want their tools to offer speed, accuracy and versatility.  Today we wanted to simplify all tenon-cutting solutions down to the three best portable options.

Option #1 - Portable Band Saws + Cross-Cutting Systems


It's becoming more and more popular among our customers to cut tenons using a portable band saw for the rip cuts and a circular saw for the shoulder cuts (you could technically use a portable band saw for every cut, but circular saws will always produce the straightest cross-cuts for this critical butt joint).

Timberwolf Tools offers two portable band saws:  the Oliver Model 12 and the Mafell Z5Ec.  The Oliver can rip timbers up to 6" deep, whereas the Mafell can rip timbers up to 12" deep - and has many other advantages, including special front & rear-cutting blades for backing out of tenon cuts.  Ben Weiss in Dorset, VT says:  "I always thought a portable bandsaw was limited to cutting decorative end-cuts on beams.  But the Mafell Z5Ec can do so much more.  I use it routinely for cutting tenons, rafter birds' mouths and scarfs.  It's a wonderful tool - fast, accurate and a pleasure to use."

YouTube Video:

You can use many types of circular saws for the shoulder cuts, but the saw must have enough cutting depth and a reliable guidance system.  For example:  the Makita 5104 Circular Saw is a good starter solution that cuts up to 3-3/4" deep and comes with a rip fence, but users generally eye-line cross cuts with this saw.  To have a precise tenon-cutting saw, one needs to look at the Mafell KSS Cross-Cutting Systems.  These track saws are able to do perfectly perpendicular tenon shoulder cuts when the smart stops on the bottom of their special cross-cutting tracks are set to 0 degrees:

Mafell cross-cutting systems can easily adjust the cutting depth:  able to elevate the blade completely above the track and set to any millimeter all the way down to max depth.  Below is a chart comparing the five different cross-cutting systems offered by Mafell:

Cutting Depth on TrackWeight with TrackPrice
KSS 80Ec/370 0 to 3-3/16" 19.8 lbs $1,824
KSS 60cc 0 to 2-3/8" 13.4 lbs $1,160
KSS 50cc 0 to 2" 12 lbs $998
KSS 400 0 to 1-15/16" 11.8 lbs $855
KSS 300 0 to 1-9/16" 6.6 lbs $930

SAVINGS OPPORTUNITY:  purchasing a Mafell Z5Ec Portable Band Saw and KSS Cross-Cutting System at the same time will trigger at least 2% savings on each tool!  For example:  adding a Z5Ec (120V) + KSS 80Ec/370 (120V) to the shopping cart at will result in $171.88 savings.  And adding more Mafell tools can potentially activate savings of 4% or 6% off!  For more information on how this works, see our Tool Combination Specials page.

Option #2 - Notch Cutting Machines

Does your shop need to cut hundreds of similar tenons?  Mafell's ZK 115Ec Notch Cutter is a workhorse of a tool capable of mass-producing tenon cuts across a series of timbers.  This machine comes standard with a Parallel Guide Fence that can interlock with the older Mafell guide rails (see photo above) or run along a straightedge of your own making.  You can easily adjust the cutting depth of the ZK 115Ec to the millimeter of your choice (just like the KSS saws above).  There are four cutter head sizes to choose from in the chart below with various cutting depths and cutting widths (and if you need more cutting width for your tenon, just move the ZK 115Ec over and follow up with another cut).

ZK 115Ec with...Cutting Depth (T)Cutting Width (B)Price
9-1/4" x 1-15/16" Head 0 to 2-3/4" 1-15/16" $7,309.00
7-7/16" x 3-1/8" Head 0 to 1-13/16" 3-1/8" $8,684.10
5-7/8" x 4-1/2" Head 0 to 1-1/16" 4-1/2" $7,087.00
5-7/8" x 2-5/16" Head 0 to 1-1/16" 2-5/16" $8,290.40

Please note:  this tool removes lots of wood chips so it is only available in the powerful 230V version!  Call us at 1-800-869-4169 if you have questions about this voltage requirement.

Option #3 - Dovetail Mortise & Tenon Systems

If you don't already have a chain mortiser (or you are in the market for a new one) first consider the all-in-one ARUNDA Dovetail Mortise & Tenon System.  Each ARUNDA dovetail system includes both male and female jigs so you can use the male to cut the tenon and the female to cut the mortise.  The router bit included in each ARUNDA system is used to quickly make both tenons and mortises (between 8 to 18 mortise/tenon joints per hour) and the largest dovetail joints support over two tons of weight!

There are seven different ARUNDA jig sizes to choose from below.  Basically you pick the timber width range that you work with most of the time, and whether you need tilting capability (such as for roof systems).  Then add the required powerful 230V Mafell LO 65Ec Hand Router and two ARUNDA Clamps completing your all-in-one tenon and mortise system.

ARUNDA JigsTimber WidthsTilting CapabilityPrice
80 N 3-1/8" to 5-1/2" Yes $4,270
120 B 4-3/4" to 8" No $3,620
80 B 3-1/8" to 5-1/2" No $3,380
50 B 1-3/4" to 4" No $3,300

Our new website has a handy calculator to help you build your own ARUNDA system:  just click Customize and Add to Cart to pick your jig size, router and clamps.  We also recommend watching the video below that demonstrates the ARUNDA system in action.

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Which option is best?

In a perfect world a timber frame shop would have all of these tools... but each of these options represents a major investment and could be a significant departure from how your shop has operated in the past.  So it's more practical to consider one of these for now.  Is every tenon in your frames different?  Do you mass-produce the same tenon size?  Do you need an all-in-one mortise & tenon solution?  We would recommend Options #1, #2 and #3 respectively for traditional timber framers, although the ARUNDA system has become a brilliant solution to many of our customers who have used it in many applications, including the replacement of classic mortise and tenons.  Our customers usually pick Option #1 these days because they prefer the portability of 120V tools, but the power and precision of 230V routers and notchers might make a conversation with your local electrician a worthwhile endeavor.  As always, please feel free to call us at 1-800-869-4169 if you have questions that would help narrow down your choice!

Football Season is Underway!

Had a wonderful visit from my brother Andrew this weekend-culminating in a wacky Bears win at Soldier Field.  Here's a photo of warm-ups before we got sunburned  :)  There were almost as many Steelers fans as there were Bears fans!

Then on Monday, Andrew helped us prepare several chain mortisers, circular saws, wheel brush sanders and curved planers for shipping at our Chicago warehouse.  It has always been an important tradition at Timberwolf Tools that we double-box and/or significantly reinforce every tool so that orders arrive at your shop in perfect condition.

Huge kudos to Andrew for doing a terrific job behind the scenes at our Maine office most of the year!  We are so blessed to have both a family business and visitors :)


Jeff Powell and the Timberwolf Tools Team
Toll free:  1-800-869-4169