Two specification sheets for one machine
A single-end tenoner with a 2000 mm round-bar slide, pneumatic clamps, and four cutterheads. The listing carries a parameter block of nine rows. The machine carries a printed panel of nine rows. They are not the same nine rows.
| Item | Listing parameters | Machine's own panel |
|---|---|---|
| Model | XJ-41 | MD-2108 |
| Power | 3 kW | 7.7 kW at 380 V installed |
| Table | 830 x 450 mm | 700 x 550 mm push table |
| Tenon length | 80 mm maximum working length | 110 mm or less |
| Saw discs | 230 mm front, 255 mm tenon | 225 mm saw, 200 mm shoulder, 250 mm flush |
| Weight | 400 kg | 380 kg |
| Spindle speed | not stated | 6000 rpm vertical shaft |
| Guide rail | not stated | 2000 mm |
Not one figure agrees. The power differs by a factor of two and a half, the table is a different size, the tenon length differs by 30 mm, the discs are three different diameters rather than two, and even the weight is 20 kg apart.
This is not a rounding problem. It is two different machines described in one place, and the only safe starting point is to assume the listing describes neither until someone confirms.
Three model numbers, three sources
| Designation | Where it appears |
|---|---|
| XJ-41 | the listing title and the parameter block |
| MD-2108 | the cover image and the printed specification panel |
| MJ105A | a rating plate fixed to the machine frame, under the rail |
The frame plate reading MJ105A is the most telling. That prefix belongs to a different family of woodworking machine in the Chinese numbering system, and a plate riveted to the base is normally the machine's own identity. Three designations on one product is what happens when a gallery is assembled from more than one build, and it means the buyer cannot tell which one will arrive.
The listing itself is filed under XJ-41, so that is the number to hold the supplier to, but the panel and the plate have to be reconciled in writing before payment.
The control panel settles the power question
One photograph shows the switch box in close-up: four red rotary switches, each marked 20 A, labelled flush saw, tenon, shoulder, shoulder. The header above them reads five-disc tenoner.
Four separately switched circuits mean four motors. A photograph of the rear of the head shows them: one large central motor driving the tenon spindle, and three smaller ones on brackets for the flush saw and the two shoulder heads, all with finned aluminium cases.
A single 3 kW motor cannot drive four cutterheads that are switched on and off independently. The panel's 7.7 kW is consistent with four motors averaging 1.93 kW each. The parameter block's 3 kW is not wrong by a little; it describes a different, smaller machine.
That single figure changes the entire installation. At 7.7 kW the machine draws about 15.6 A on 380 V three phase, so it needs a 20 to 25 A breaker and a 4 square millimetre feed. As a 3 kW machine it would draw 6.1 A and run from a much lighter circuit.
What five discs across four motors means
Five cutters and four drives is a coherent arrangement once you look at the work: the flush saw trims the end square in one disc, the tenon head carries two discs on one arbor to cut both cheeks at once, and the two shoulder heads each carry one disc to clean up the shoulders.
Practically, it means you can bring cutters in one at a time and see which one is doing the work. It also means a single blunt disc stops the job while three good ones sit idle, so a second set of the 225 mm tenon discs is the spare to hold.
6000 rpm and three rim speeds
The panel states 6000 rpm on the vertical shaft. Rim speed follows from diameter and speed, v = pi x D x N / 60000:
| Disc | Role | Rim speed at 6000 rpm |
|---|---|---|
| 250 mm | flush saw, trims the end square | 78.54 m/s |
| 225 mm | tenon head | 70.69 m/s |
| 200 mm | shoulder head, one each side | 62.83 m/s |
The 250 mm flush saw reaches 78.5 m/s, which is a high rim speed and sits in saw-blade territory rather than cutterhead territory. That is not automatically wrong, but it means the rating stamped on each disc governs whether 6000 rpm is permitted. A disc bought later from a different source with a lower marking would not be safe on this spindle, and a 250 mm blade rated for 5000 rpm would be over its limit by 20 percent here.
Ask for the marking on the discs supplied, and write the 6000 rpm spindle speed into your spare parts specification so nobody substitutes a slower blade.
110 mm of tenon on a 225 mm disc
A tenon has to be cut to its full length by a disc that can reach that far. The arithmetic is blunt:
| Disc | Radius | Projection a 110 mm tenon needs | Left over |
|---|---|---|---|
| 225 mm | 112.5 mm | 110 mm | 2.5 mm |
| 200 mm | 100.0 mm | 110 mm | minus 10.0 mm |
A 225 mm disc leaves 2.5 mm of radius unused when cutting a 110 mm tenon. That is a real ceiling, not a comfortable one: the arbor and collar have to sit almost entirely below the table for the disc to expose 110 mm. And a 200 mm disc cannot reach 110 mm at all, which confirms the 110 mm figure belongs to the 225 mm tenon head.
If your work needs tenons longer than about 100 mm, this is the number to test on a sample before committing to a batch. It is also the reason the listing's 80 mm may be the honest figure for a smaller machine.
The supply you actually need
| Figure | 380 V three phase | 220 V single phase |
|---|---|---|
| 7.7 kW, as the panel states | 15.6 A | 46.8 A |
| 3 kW, as the listing states | 6.1 A | 18.2 A |
On 220 V single phase, 7.7 kW needs 46.8 A, which is not a workshop circuit, it is a service upgrade. The machine is a three phase machine and the panel says so.
If you are buying for a site without three phase, this machine is the wrong purchase, and the listing's 3 kW figure is exactly the kind of number that makes people think otherwise.
Pneumatics are not optional
Both the workpiece clamp and the feed are air driven. The clamp sits on a swing arm with a vertical cylinder, and there is a second cylinder for feed, with a regulator and gauge mounted low on the frame.
So the machine does not run without compressed air, and neither the working pressure nor the free air per cycle is published. A tenoner cycles the clamp twice per piece, so at a few hundred pieces a shift the compressor sizing matters, and a small single-phase compressor will not keep up with a 7.7 kW machine's cycle rate.
2000 mm of rail, and the stroke nobody states
The guide rail is 2000 mm and the overall machine length is also 2000 mm, so the rail runs the full footprint. The push table is 700 x 550 mm.
What matters for capacity is the carriage stroke, and that is not stated anywhere. The rail length tells you how far the table can travel, not how far it does travel. For a tenoner the stroke sets the longest workpiece you can machine in one pass, and it is the first thing to measure when the machine arrives.
If your product is door stiles or window frames in the 1.5 to 2 m range, confirm the stroke against your longest part rather than against the rail figure.
Four hundred kilos in four cubic metres
| Basis | Figure |
|---|---|
| Overall size | 2000 x 1685 x 1300 mm |
| Volume | 4.38 cubic metres |
| Actual mass | 0.38 tonnes |
| Sea LCL chargeable | 4.38 W/M, so volume governs |
| Air volumetric | 730 kg, against 380 kg actual |
The footprint is what costs money here, not the mass. Sea freight bills on whichever is greater, weight in tonnes or volume in cubic metres, and 4.38 cubic metres against 0.38 tonnes means you pay for volume. Air freight is worse: 730 kg volumetric against 380 kg actual.
So a quotation that looks competitive at the machine price can lose on freight, and a machine that folds down or ships with the rail detached changes the number. Worth asking how it is crated.
What a tenoner does that a slot mortiser does not
The two are constantly confused. A slot mortiser plunges a chisel or cutter into a component to cut the mortise, the rectangular hole. A tenoner cuts the tenon, the tongue that goes into it, and does so by passing the work across rotating discs.
If your requirement is the hole, the XJ-39 horizontal slot mortiser in this catalogue is the right family. If it is the tongue, and you want the shoulders and the end squared in one handling, this is the machine. Buying the wrong one of the two is the most expensive mistake in this category, because neither can do the other's job.
What is not published
| What a buyer needs | What the page gives |
|---|---|
| Which model is actually shipped | three different designations |
| Installed power, confirmed | 3 kW in the parameters, 7.7 kW on the panel |
| Motor count and individual ratings | four switches are visible, no motor figures |
| Maximum workpiece thickness | 100 mm in the parameters, absent from the panel |
| Carriage stroke | nothing; the rail is 2000 mm but the stroke is not stated |
| Air pressure and consumption | nothing, although the clamps and feed are pneumatic |
| Tenon height range and shoulder height | nothing |
| Disc bore, thickness and tooth count | diameters only |
| Dust extraction port size | nothing |
| Spindle adjustment range | nothing |
What to put in the enquiry
| Question | Why it decides something |
|---|---|
| Which model number goes on the invoice | three designations appear and they are not interchangeable |
| Nameplate photograph with the rating in full | settles power, voltage, phase and current in one image |
| Individual motor ratings and how the 7.7 kW is made up | decides the breaker, the cable and the generator |
| Is the site single phase or three phase | at 7.7 kW a single phase supply is not an option |
| Maximum workpiece thickness, and whether it is a through cut | the 250 mm flush saw limits what it can span |
| Carriage stroke, not rail length | stroke sets the longest workpiece you can machine |
| Air pressure and free air consumption per cycle | clamps and feed are pneumatic, so the compressor has to be sized |
| Disc specification: bore, thickness, teeth, and the marked maximum speed | 6000 rpm puts the 250 mm disc at 78.5 m/s |
| Dust port diameter | a tenoner makes chips at four heads at once |
Before you order
Ask for one photograph: the nameplate, in focus, with the rating in full. That single image settles the model number, the power, the voltage, the phase and the current, and it is the only document the supplier has published that would resolve the contradictions.
Then ask which of the three designations goes on the invoice. If the answer is vague, the machine is a mixture of builds and the spare parts will not match.
Finally, test a 110 mm tenon on a sample of your own stock before the batch order. The 225 mm disc leaves 2.5 mm of margin at that length, and margin that thin is worth proving rather than assuming.
Frequently asked questions
Is this a single-end tenoner or a mortiser?
A single-end tenoner. It cuts the tenon, the tongue, by passing the work across rotating discs, and it squares the end and cleans the shoulders in the same handling. A slot mortiser cuts the mortise, the hole. They are not interchangeable.
Is the power 3 kW or 7.7 kW?
The machine's own panel says 7.7 kW installed at 380 V, and a photograph of the head shows four separate motors. The control panel has four independently switched circuits on 20 A rotary switches. A single 3 kW motor cannot drive four separately switched cutterheads, so the 3 kW in the parameter block describes a different machine.
Why does the model number matter so much?
Three designations appear on one product: XJ-41 in the title and parameters, MD-2108 on the cover and the specification panel, and MJ105A on a plate fixed to the frame. Spare discs, arbors and belts are ordered against a model number, so an ambiguous one is a real risk.
What supply does it need?
At 7.7 kW it draws about 15.6 A on 380 V three phase, so a 20 to 25 A breaker and a 4 square millimetre feed. On 220 V single phase the same power needs 46.8 A, which is not a workshop circuit. This is a three phase machine.
How long a tenon can it cut?
The panel states 110 mm or less. A 225 mm disc has a 112.5 mm radius, so a 110 mm tenon uses 98 percent of it and leaves 2.5 mm for the arbor and collar. That is the physical ceiling, so treat 110 mm as a limit to test rather than a comfortable working figure.
What is the rim speed of the discs?
At the stated 6000 rpm the 250 mm flush saw runs 78.54 m/s, the 225 mm tenon disc 70.69 m/s and the 200 mm shoulder discs 62.83 m/s. The 250 mm figure is high, so the maximum speed marked on each disc decides whether it may be run at 6000 rpm.
Are the clamps manual or pneumatic?
Pneumatic, both the clamp and the feed. The clamp is a vertical cylinder on a swing arm and there is a second cylinder for feed, with a regulator and gauge on the frame. Compressed air is required, and the working pressure and free air per cycle are not published.
What is the freight cost driven by?
Volume, not weight. The machine measures 2000 x 1685 x 1300 mm, which is 4.38 cubic metres against 0.38 tonnes, so sea LCL bills on volume. Air freight works out at 730 kg volumetric against 380 kg actual, so it also bills on volume.
Key specifications
Frequently asked questions
- Is this a single-end tenoner or a mortiser?
- A single-end tenoner. It cuts the tenon, the tongue, by passing the work across rotating discs, and it squares the end and cleans the shoulders in the same handling. A slot mortiser cuts the mortise, the hole. They are not interchangeable.
- Is the power 3 kW or 7.7 kW?
- The machine's own panel says 7.7 kW installed at 380 V, and a photograph of the head shows four separate motors. The control panel has four independently switched circuits on 20 A rotary switches. A single 3 kW motor cannot drive four separately switched cutterheads, so the 3 kW in the parameter block describes a different machine.
- Why does the model number matter so much?
- Three designations appear on one product: XJ-41 in the title and parameters, MD-2108 on the cover and the specification panel, and MJ105A on a plate fixed to the frame. Spare discs, arbors and belts are ordered against a model number, so an ambiguous one is a real risk.
- What supply does it need?
- At 7.7 kW it draws about 15.6 A on 380 V three phase, so a 20 to 25 A breaker and a 4 square millimetre feed. On 220 V single phase the same power needs 46.8 A, which is not a workshop circuit. This is a three phase machine.
- How long a tenon can it cut?
- The panel states 110 mm or less. A 225 mm disc has a 112.5 mm radius, so a 110 mm tenon uses 98 percent of it and leaves 2.5 mm for the arbor and collar. That is the physical ceiling, so treat 110 mm as a limit to test rather than a comfortable working figure.
- What is the rim speed of the discs?
- At the stated 6000 rpm the 250 mm flush saw runs 78.54 m/s, the 225 mm tenon disc 70.69 m/s and the 200 mm shoulder discs 62.83 m/s. The 250 mm figure is high, so the maximum speed marked on each disc decides whether it may be run at 6000 rpm.
- Are the clamps manual or pneumatic?
- Pneumatic, both the clamp and the feed. The clamp is a vertical cylinder on a swing arm and there is a second cylinder for feed, with a regulator and gauge on the frame. Compressed air is required, and the working pressure and free air per cycle are not published.
- What is the freight cost driven by?
- Volume, not weight. The machine measures 2000 x 1685 x 1300 mm, which is 4.38 cubic metres against 0.38 tonnes, so sea LCL bills on volume. Air freight works out at 730 kg volumetric against 380 kg actual, so it also bills on volume.