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Lamello Top 21 Review

Biscuit joinery at its best!

Most woodworkers are familiar with biscuit joinery. But what they might not know is that there are really only two types of biscuit cutters: the Lamello, and all the rest. I know biscuits—I’ve been using them to assemble panels for over twenty years. And after putting Lamello’s new Top 21 machine to the test, I realized I could never go back to using another manufacturer’s. If you have an appreciation for stepping up your game in fine joinery, then read on. Keep in mind, however, that this tool comes with a hefty price tag. I’ll tell you why it’s worth it.


Lamello is the company that introduced biscuit joinery to the industry. Their machine is the standard by which every other cutter is measured. It’s the brainchild of Hermann Steiner, the founder of the company. In December of 1955, he had a vision, described here, in his own words:

…I saw how we could use a groove cutter to cut short opposing grooves into the panels and connect them using small biscuit elements. In contrast to continuous grooves, this procedure would not weaken the board. (source)

And with his vision, the “Lamello” machine was born, transforming the way we join panel products in modern woodworking.

The Test

As I’m sure you are aware, there are other options for joining panel and solid wood assemblies, such as Dominos, dowels, tongue and groove milling, etc. That’s why it’s important to recognize that each method has a strength and weakness.

So, why use biscuits?

The biscuit joint is fast, strong, and particularly suited for panel product assembly. Even though other biscuit machines can perform many of the same functions conducted in this test, only the Lamello was built to do it accurately and repetitively. The Top 21 has been engineered for small shop production with large shop accuracy.

Although various wood thickness can be used, biscuit joinery is designed primarily for 3/4-in. material.

Therefore, Lamello designed their “fixed position” fence…

(Note: Click any image to enlarge)

…to easily accommodate centering the slot on a 3/4-in. panel.

What is unique to the Top 21 machine is an adjustment dial that allows you to move the blade height up to 2mm in each direction.

The dial has positive stops every .1mm for placing that slot exactly where you want it.

Most standard biscuit cutter fences require you to index off the back or inside of a miter joint, which creates sloppy alignment if the wood varies in thickness.

Lamello’s smart fence system provides the ability to index off the face side of the miter,…
…which results in perfect alignment each time.

This is accomplished by an accessory fence with a 45 degree indexing notch.

The outside edge of the mitered wood piece tucks securely into place for accurate slotting.

Rather than using a slot cutter or dado blade for full-length grooves, you can press a biscuit cutter into service to do the same thing. The Top 21 has very smooth guide-ways in the body construction, making this technique extremely easy.

To illustrate a slot groove joint application, a stopped continuous groove is cut into the end of an apron panel.
Next, a couple biscuit slots are machined into the adjoining side panel.
To join the two elements, apply a little glue, and the precisely grooved apron is slid into place as it indexes off the two biscuits.
For specialty applications and for machining thicker wood, a separate fence is attached via CNC-machined dovetail slots. Adjustments are deliberate and smooth.
The loose fence is installed on the fixed fence for thick boards or offset joinery, or on the bottom of the machine for stable vertical machining.

With the help of a straightedge guide, face slots are quickly grooved for a multiple-shelf cabinet unit.

The Lamello also makes quick work of attaching solid wood frames.

Slots are machined into the face of the cabinet edge…
…and the back of the face frame.

This is where I discovered how accurate the Lamello Top 21 is compared with other biscuit cutters; perfect alignment was achieved on the first attempt every time.

The Lamello company also offers other joinery solutions, such as the E20, which are plastic self-clamping fasteners. These are great options for quick assemblies or difficult-to-clamp situations.

To assemble an edge miter, the mating pieces are machined together,…
…creating a half slot in each end.

Glue is added to the joint, and the E20-H is simply driven into place (see left photo, below). No clamps are needed, as the molded ribs on the biscuit pulls the joint snugly together (see right photo, below).

Similarly, the E20-L is used for face miters.
Again, the two pieces are machined simultaneously, only this time on the face of the board.
The opposing ribs on the fastener force the joint together as it gets pounded in.
For knockdown joinery, Lamello has developed the Clamex fastener. Unlike a standard 4mm biscuit slot, the Clamex requires an 8mm slot.
The company sells an optional 8mm cutter, but I used the included 4mm blade. By simply dialing down the fence the additional 4mm distance, a precisely machined 8mm slot was created.
Once the slots are cut, a small access hole is drilled on the face of one of the panels to access the clamping screw.
Because the Clamex pulls each piece together, the plastic halves need to be screwed into the slots.
To tighten and loosen, a driver is inserted into the set-screw via the access hole.
There are even Lamello-shaped hinges that can be quickly mortised for inset cabinet doors.

Because the hinges require a shallow cut, the Top 21 auxiliary fence is stepped down to accommodate the blade recess.

Once the two slots are cut, the hinge is quickly installed…
…with both door and frame perfectly aligned.

I like the concept of the Lamello hinge, but will have to reserve final judgment until after I use them on an actual job. The hinge is sturdy enough, but the loose pin and light-duty metal may be too yielding for jobs requiring heavy usage.

Top 21 Features

Like a finely tuned automobile, the Top 21 has been engineered for durability and accuracy. The Top 21 has many unique features. I’m going to list just a few in this concluding overview (source).

New features:

•    Powerful 800W motor with electronic control, soft start, and speed control
•    A new base plate that sits flush on both sides for more efficient positioning on the workpiece
•    Height adjustable cutter dial that allows you to make micro adjustments to the position of the blade

Tried and true features:

•    CNC-machined parts for precision referencing and smooth operation
•    Separate base plate for multiple functions, including easy indexing off miter joints and large surface area for vertical joining applications
•    6 standard cutter depth adjustment dial

Optional accessories:

•    8mm cutter for Clamex connector (standard biscuit cutter is 4mm)
•    Sliding shoe for cutting expansion gaps
•    Edge trimming unit for flush trimming wood edges
•    A variety of optional fasteners, including the standard sized wood biscuits, Clamex connector, K20 clamping element, Duplex furniture hinge, Simplex connector, and E20 self-clamping elements

The Lamello Top 21 is available through Colonial Saw, and the price is $1,195. Yes, most cutters can be purchased for under $200. The Top 21 is an expensive tool. Lamello sets the bar pretty high, and the price reflects it.


23 Responses to “Lamello Top 21 Review”

  1. Ray Menard

    “…But what they might not know is that there are really only two types of biscuit cutters: the Lamello, and all the rest.”

    I completely agree. And now I can see that it is time for me to retire the 15 year old model and avail myself of the ease and precision of the new version. One advantage right off is that you can plug your Festool Vac hose to it without the convoluted mods I had to go through. The micro adjustment is a great upgrade of an already very precise tool. The Domino is an excellent tool as well but the Lamello allows for a fudge factor in applications such as setting face frames to a cabinet that the Domino cannot compete with because it is TOO precise.

    Add the options for specialty hardware and connectors as described in your article David and this Lamello 21 is a must have for the 21st century woodworker. Thanks for the detailed review.

    • Ray Menard

      … on the other hand, at $ 1,195.00 + I may sit on this upgrade for some time to come. I have to laugh – I was pretty excited to read all about these new features but am now quite subdued by the cost. Maybe a present from my wife on whatever anniversary is represented by the “red tool” gift.

  2. Aaron

    I have the Classic C3. What are the salient differences between that model and this one, as pertains to accuracy and versatility?

    • david getts

      Hi Aaron,
      The C3 is probably just as accurate, the Top 21 just gives you a few more options and features to work with. I’d say the dial micro-adjustment is the most significant upgrade. It really simplifies setup. I also like the way the swiveling fence is designed to fit flush, rather than overlaying the machine body (better positioning in tight corners). Plus, the measuring guide for both angle and height adjustment has been positioned to read from the same side. And last, they’ve added the dovetail guide-ways to the bottom of the base plate (I don’t believe the C3 is set up this way) so a broader fence can be be added for stability in vertical work.

  3. Sternberg

    Nice infomercial, but nothing here that I can’t do just as well with a Porter Cable, for 20 cents on the dollar.
    You would think for that price, they would make one with fractional adjustments rather than metric.

    • john r graybill

      The second line defines the first.
      I frame walls and build house with fractions, with cabinets and furniture I use the Metric system.

    • Justin

      Or they know that anyone buying one of these should be able to divide or multiply to simply adjust for that.

      [Comment edited by TiC editorial staff]

  4. Steve R

    The review is spot on. I have had the Lamello C2 for about 8 years and its machined surfaces put both my Porter Cable and DeWalt joiners to shame (neither one could achieve slots that were actually parallel to the reference surface or bottom plate). The Lamello slots are perfectly parallel. The PC and DeWalt were sold off years ago after experiencing the differences first hand. The Lamello is well worth the premium.

    On the subject of the Lamello hinges, they are good except for the screws that come with them. They have oval heads and need to be flat heads. First attempt at their use and it will be obvious why. On this issue, Lamello really fumbled the ball.

  5. john r graybill

    I have the Top 20 and along with the Domino those bases covered but, I do like the Top 21’s leading edge guide for mitres instead of the back side on the 20, too much room for error.
    My Top 20 has an easy attachment for my Festool Vac. The down side is it won’t sit flat in the Systainer but what the hell.

    My Top 20 was $800 when purchased new, I’ve since gone thru at least six boxes of Lamello biscuits. On a per biscuit cost it was worth it especially; excluding my screw-ups, the Top 20 has performed perfectly every time. That little up and down dial was a stroke of genuis on their part.
    If I get a job involving hundreds of mitred corners I’ll get the Top 21. The labor savings and piece of mind will be worth it.

    • john r graybill

      After looking closly at the pictures I see the Top 21 will fit flat in the systainer. mea culpa

  6. Larry Schweitzer

    I’ve had Lamello machines for over 25 years, any comparison to Dewalt and similar knock offs doesn’t hold water. For those still using fractions I feel for you. Too bad this country is still out of step. Once you learn to use the machine almost no measuring is needed. Lamello for panels, Domino for solids, both great machines for those that can appreciate quality and precision.

  7. Sam Marsico

    Hey Festool,
    How about a clever knockdown fastener system for the Domino?

  8. Warren

    Love the adjust ability of the Top21 and it definitely qualifies as a production shop tool. Not sure I would give up my current jointer as it covers 99% of the joints I need to do.

    Lamello has certainly got the right idea on what to put into the slots, and it is pretty hard to beat all of their options.

    Good article.

  9. J. Alvis

    Thanks for the Article. I was unaware of the Screw-In Clamex fastener. The 21 is certainly on my list….the knock offs just don’t meet the standard.

  10. W.A.Strahan

    why doesnt lamello make a double edged “barbed”plastic biscuit ?think of how nice it would be to attache face frames without clamps am i missing something here ?
    and while they’re at it make some out of pvc for working with azek

    • david getts

      They do make a barbed biscuit, it’s called the K-20 clamping plate. I’ve used them in field applications where a clamp could not be set. They work well enough, but don’t have enough holding power to pull things real tight…especially with hardwood that’s not perfectly flat.

  11. Gerard De Lany

    Ummm, a question here: Someone is offering a Lamello Top (maybe it’s the original joiner?) blue plastic, gold powder coat, for a couple hundred. The Top Twenty One and even the Classic X are out of my league price – wise. Is the older Top enough of an improvement over the PC 557 to justify buying and using that, or should I just save my money until I can get the Classic X or Top Twenty One? I have a couple custom cabinets to make and install on a job coming up soon – I can afford the old Top, or maybe squeeze enough for a used Classic X, but the Top Twenty One is a year of savings down the road.

  12. david getts

    I’m not too familiar with the older models (did Lamello ever have a blue & gold color?). However, if you’re looking for a certain upgrade over what you have, I’d wait until you’re able to buy the new model.


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