Aluminium profile CNC milling machine with a pneumatically tilted clamp beam (3+1 axis)
3+1-axis profile mill · three CNC axes over a clamp beam or table that a pneumatic cylinder indexes to −90°, 0° and +90°
A window or facade shop that mills drainage slots, lock and handle pockets and fixing holes in aluminium bars does not always need a servo-controlled tilting spindle. A cheaper class of machine keeps the spindle vertical and turns the profile instead: the vices sit on a beam or table that a pneumatic cylinder swings to −90°, 0° or +90°, giving three faces from one clamping. Before buying, check the section that fits under the spindle, the X stroke against the longest bar, how tools are changed, and whether any angle between the stops is needed.
Three-axis CNC milling and drilling machines for aluminium, light-alloy and PVC profiles whose additional axis is a pneumatically indexed tilting clamp beam or work table with fixed positions (−90°, 0°, +90°, with manual intermediate stops on some models), with vertical electro-spindles taking ER collets or a small automatic tool magazine. Four-axis profile machining centres with a servo-driven swivelling spindle (A axis), large tool magazines and shuttle zones are covered on the Aluminium profile CNC machining centre page; dedicated drilling machines with fixed drill units on the Aluminium profile drilling machine page; and machining centres for aluminium parts rather than bars on the Aluminum CNC milling machine page.
CNFX editorial research · Sources checked October 12, 2026 · 3 sources
The pneumatic tilting beam: three fixed faces instead of a swivelling spindle
On these machines the profile, not the spindle, changes angle. ACM Machinery describes its C4 four-metre vertical machining centre as able to work three sides of a profile, with a pneumatic tilting working table at +90°, 0° and −90° and intermediate angles obtained by mechanical stops; CNC-controlled electronic rotation is optional. [3]
DEMAC's SK series is sold as 3+1 axis with the working table tilted to −90°, 0° and +90° by pneumatics, with a servo-driven tilting table offered as an option. [1] Mecal's MC 319 Aydo and MC 309 Nike, both listed as 3 axis CNC + 1, give the pneumatic A-axis rotation as 45-90-45 degrees; on the Aydo intermediate degrees are a manual option, and on the Nike intermediate degrees are manually preset with a pneumatic block. The four pneumatic vices of the Aydo slide on the tilting beam. [2]
In the same Mecal catalogue, the MC 305 Kosmos and MC 307 Falcon are four-axis CNC machines with A-axis rotation of ±125°, the servo-controlled alternative. [2] Editorial note: with a pneumatic beam the program cannot call an arbitrary angle. A hole or slot at, say, 30° to a face is only possible if a mechanical stop is set to that angle before the batch, or with an angle head; list every angled feature before choosing this class of machine.
Send drawings of every feature with the face it is on and its angle to the face, so the supplier can confirm which features the fixed positions and any preset stops reach.
02
Section under the spindle, X stroke and how tools are changed
The section that can be milled is small next to the X stroke, so check the largest profile cross-section first, then the bar length.
DEMAC's page states its X working length can be customised from 1.2 m to 7.2 m, with feed rates up to 30 m/min in X and 15 m/min in Y and Z, and an air supply of 0.5 to 0.8 MPa. [1] The same page refers to a 4.0 kW electro-spindle in its text while the table lists power as 6 kW; ask DEMAC which figure is spindle power and which is total power. [1]
Editorial calculation: at DEMAC's 30 m/min maximum X feed, a full traverse takes 3000 / 500 = 6 s on the SK-3000 and 8 s on the SK-4000 (30 m/min = 500 mm/s). [1] Bars longer than the stroke have to be machined in two clampings or on a longer bed.
2,800 to 18,000 rpm by frequency inverter; 11-tool changer [3]
Not stated
Give the largest profile section (width × height), longest bar, alloy, every tool diameter and length, and whether tool changes may be manual (collet) or must be automatic.
03
Micro-drop lubrication, air supply and guarding on a light profile mill
DEMAC lists lubrication by micro drop with pure oil and a light-curtain system on the SK series, and the pneumatic tilting table relies on the 0.5 to 0.8 MPa air supply. [1]
DEMAC's CNC unit handles linear and circular interpolation on two axes at a time (X-Y, X-Z or Y-Z) and is programmed in ISO code or through an aided-geometry system; it also mentions a software library of profiles and tools. [1] Editorial note: two-axis interpolation is enough for slots and round holes in one plane; ask for a demonstration if a feature needs simultaneous motion in all three axes.
04
Data for a 3+1-axis profile milling machine quote
Paste it into your enquiry below or into an email to a maker, then replace every bracket.
Profiles: [alloy; largest section W × H; longest bar; wall thickness]
Features: [type; face; angle to face; tolerance]
Angles: [−90/0/+90 only; intermediate stops needed]
Spindle: [power; speed; ER collet or tool magazine; largest tool]
Clamping: [number of vices; manual or automatic positioning]
Site: [compressed air pressure; power supply]
Software: [ISO code; profile library; CAD import]
DEMAC's SK series page gives 3000 and 4000 mm strokes, a pneumatic −90°/0°/+90° table and ER25 tool holders.
DEMAC
Manufacturing site to be confirmed for the order
Lists the SK series 3+1-axis aluminium CNC routing machine with a pneumatically tilted −90°/0°/+90° working table, 3000 or 4000 mm X stroke and 4 or 6 clamps.
Explore company information and manufacturing capabilities, then discuss the scope of your project with a relevant supplier.
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Compiled and source-reviewed by the CNFX editorial team.
Each manufacturer above links to the page on that company's own website where the product is listed, with the date we checked it. How we source and review
· Page last updated 13 October 2026
Buyer questions
What does 3+1 axis mean on a profile milling machine?
Three CNC axes plus a fourth that tilts the clamp beam or table pneumatically to fixed positions; DEMAC and ACM Machinery list −90°, 0° and +90°. [1][3]
Can a pneumatic tilting table machine angles between the stops?
Only at preset positions: Mecal lists manual intermediate degrees, and ACM Machinery uses mechanical stops, with CNC rotation as an option. [2][3]
How large a profile section fits?
Published values include 180 × 150 mm for DEMAC's SK series and 200 × 170 mm for Mecal's MC 309 Nike. [1][2]
Sources and what still needs a direct check
Sources checked 2026-10-12. DEMAC and Mecal publish data for their own profile machining centres; the ACM Machinery description is a product listing in Window + Door, a National Glass Association magazine.
