Aluminium Angle Extrusion 40x40x5 mm for Frame Assembly and Bracing

OEM / ODM Available Free Sample Available Mill certificate to EN 10204 3.1 on request, RoHS and REACH declarations

40 x 40 x 5 mm aluminium angle extrusion in 6061-T6 for frame assembly and bracing. Solid section, drilled and tapped to drawing, with M6 and M8 threads in the 5 mm wall.

Wholesale Price Quoted against size, drilling, finish and quantity per per piece or per metre

Material	Aluminium
Alloy Grade	6061-T6
Temper	T6
Section Size	40 x 40 x 5 mm equal leg angle
Slot	Solid angle, no slot; assembles with 40 series 8.2 mm slot T-nuts
Length	Saw cut to length, ends square or 45 degree mitre, +/-0.5 mm
Tolerance	EN 755-9, wall +/-0.15 mm; hole position +/-0.2 mm
Surface	Mill finish / clear anodised / black anodised
MOQ	Made to order; small quantities from stock
Lead Time	Typically 1 to 2 weeks for cutting and drilling, plus a week for anodising
Loading Port	Shanghai, Ningbo, Qingdao, Shenzhen
Supply Ability	In-house saw cutting, drilling, tapping and CNC machining
Payment Terms	T/T 30 per cent deposit, balance against copy of bill of lading
Trade Terms	FOB, CIF, CFR, EXW
Certifications	Mill certificate to EN 10204 3.1 on request, RoHS and REACH declarations

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An aluminium angle extrusion drilled to a hole pattern. Edge distance and thread engagement in the 4 to 5 mm wall set the bolt size.

01What is this angle used for?

This is the 40 x 40 x 5 mm aluminium angle extrusion, and it answers a specific job: taking a T-slot frame from a loose set of profiles and making it a rigid shape. The angle bolts across a corner, ties a panel to a frame, or braces a bay against racking. It is a solid 6061-T6 section with a 5 mm wall, so it takes M6 and M8 threads properly, unlike the thin bent angle that strips out after two rebuilds.

The page below is not about the section, it is about working the section: where to put the holes, how far the hole has to sit from the edge, how much thread a 5 mm wall actually gives you, and how the cut tolerances stack up across a frame.

Can I tap M8 into a 5 mm wall?

Yes, but the thread engagement is short. A 5 mm wall gives 7 full threads on an M8 (1.25 mm pitch) and 8 threads on an M6 (1.0 mm pitch). That is enough for a static joint in 6061-T6 but not enough for a joint that is opened and closed repeatedly. Add a T-nut or a nut on the back face for anything that gets rebuilt.

How far must a hole sit from the edge?

At least 2x the hole diameter, and on 6061-T6 I prefer 2.5x. An M8 hole should be at least 16 mm from the edge and preferably 20 mm. Closer than that and the bolt will tear out the edge under load, no matter how strong the alloy is.

The 35 x 35 x 4 mm angle, drilled and deburred. Hole positions are set from the inside corner so the pattern carries across to the mating profile.

02Machining the angle: cut, drill, tap, deburr

The angle arrives as a stock length. Four operations turn it into a part, and each one has a tolerance that feeds the frame’s final accuracy.

Operation	Tool	Held to	Feeds the frame as
Cut to length	CNC saw, carbide blade	+/-0.5 mm	frame diagonal grows 0.7 mm
Mitre cut	CNC saw, 45 degree	+/-0.5 degrees	corner gap up to 0.3 mm
Drill	CNC or radial drill, HSS or carbide	+/-0.2 mm position	bolt pulls the joint to position
Tap	machine tap, M6 or M8	6H class	thread engagement on the wall
Deburr	hand or vibratory	no burr over 0.1 mm	parts seat flat

The two cuts matter most. A frame is a closed loop of members, so the length errors add up around the loop and then have to go somewhere: they close up as an out-of-square frame or as a bow in one member. Holding the cut to ±0.5 mm keeps the accumulated error under a millimetre on a normal four-sided frame.

The deburr is not cosmetic. A 0.2 mm burr on the end face stops the angle seating flat against the member it is bolted to, and the joint then flexes. Specify a deburred face, and specify the face that becomes the datum.

03Mixing a solid angle with a T-slot profile

The common assembly in this catalogue is a solid angle bolted to a T-slot profile. The T-slot side has a slot with a known width, and the bolt has to match it. The table below maps our slot series to the bolts and T-nuts that fit.

Slot series	Slot width	Fits bolts	T-nut to use	Typical angle
20 series	6.2 mm	M5, M6	20 series T-nut	20 x 20 x 3 mm
30 series	8.2 mm	M6, M8	30 series T-nut	30 x 30 x 4 mm
40 series	8.2 mm	M6, M8	40 series T-nut	35 x 35 x 4 mm
45 series	10.2 mm	M8, M10	45 series T-nut	40 x 40 x 5 mm
50 series and up	10.2 mm	M8, M10, M12	heavy series T-nut	50 x 50 x 9 mm

The sequence matters. Drop the T-nut into the slot first, slide it to the hole position, then bring the angle up and start the bolt by hand before you torque it. If you torque a bolt into a T-nut that is not seated, the nut rotates 90 degrees in the slot and locks; the only way out is to cut the bolt.

Hole pattern for the common joint

Corner joint, 40 series: two M8 holes 20 mm apart on the 40 mm leg, both 20 mm from the inside corner.
Panel to frame: M6 holes at 150 to 200 mm pitch, 15 mm from the edge.
Diagonal brace: M8 at each end, hole centre at half the leg length so the bolt sits on the neutral axis.
Base to floor: M10 or M12 through the angle and into an anchor, hole at least 20 mm from the edge.

04How the tolerance chain accumulates in a frame

A frame of four angle-braced members is a closed loop of tolerances. Each contribution is small; the loop sum is what you see as an out-of-square frame.

Contribution	Per joint	In a 4-corner frame	Effect
Cut length error	+/-0.5 mm	+/-1.0 mm on a side	frame width varies
Mitre squareness	+/-0.5 deg	+/-1.0 deg	corner gap or step
Hole position error	+/-0.2 mm	+/-0.4 mm	bolt pulls the joint to position
Hole clearance M8 normal	+0.2 to +0.5 mm	absorbs the above	small, forgiving
Bolt hole in slotted form	up to +2 mm	absorbs a lot	adjustable, less rigid

The practical conclusion: cut length and mitre squareness dominate. Hole position errors are absorbed by the bolt clearance. Buyers who are chasing a square frame should spend their tolerance budget on the saw, not on the drill.

05Choosing the section for the joint

Choose the solid angle

The corner takes a real moment from a panel or a load
You need threads you can tighten without a T-nut
The joint is bolted to a flat face, not into a slot
You want a visible finished corner with no slot is visible
The assembly gets rebuilt and needs to survive it

Choose a T-slot profile gusset

The joint is inside a slot, with no flat face to land on
You need the joint to be adjustable after assembly
The frame is taken apart often, so T-nuts are wanted
You want a flush corner with no external angle
The frame is all in one profile family and the buyer wants one bill of materials

06Failure modes on an assembled corner

What goes wrong	Why it happens	Design it out by
Thread strips in the 5 mm wall	M8 in a 5 mm wall is only 7 threads, re-torqued too often	use M6, or add a T-nut or a back-face nut
Bolt tears out the edge	hole under 2x the diameter from the edge	keep M8 at least 16 mm, ideally 20 mm, from the edge
Corner rocks under load	the angle is bolted to a T-slot face that is not flat	seat the angle on the profile face, not on the slot lip
Frame will not go square	cumulative cut and mitre error in a closed loop	hold the cut to +/-0.5 mm and the mitre to +/-0.5 degrees
Anodised angle will not earth	the anodised film is an insulator	mask a bonding pad or grind a patch back to bare metal
Joint loosens in service	vibration on a static joint	use a serrated washer or a thread-locking compound

07What to check before you order a drilled angle

Procurement checklist for a drilled and tapped angle

Confirm the section: for example 40 x 40 x 5 mm.
Confirm the alloy and temper: 6061-T6 is standard.
Send the hole pattern as a drawing, with edge distances.
Confirm the thread: M6 or M8, and whether a T-nut is used.
Confirm the end cut: square or 45 degree mitre.
Confirm the deburr requirement and the datum face.
Confirm the finish, and mask the bonding point if earthing matters.
Confirm the quantity and the packing.

08Questions buyers ask

Can you drill and tap the angle to my drawing?

Yes. Send the drawing with hole positions, thread sizes and edge distances, and we drill and tap to ±0.2 mm hole position.

How much thread does a 5 mm wall give?

Seven threads on an M8 and eight on an M6. That is fine for a static joint, but add a T-nut or a back-face nut for a joint that is taken apart often.

What bolt fits the 40 series slot?

The 40 series slot is 8.2 mm wide and takes M6 and M8 with a 40 series T-nut.

How square will the finished frame be?

With a ±0.5 mm cut and a ±0.5 degree mitre, a four-sided frame stays within about 1 mm on the diagonal.

Can the angle be anodised after drilling?

Yes. The anodising covers the cut and drilled faces; if the joint has to earth, mask a bonding point first.

What is the lead time?

One to two weeks for cutting, drilling and tapping, plus a week if anodising.

What we need to quote a drilled angle

The section and wall: for example 40 x 40 x 5 mm.
The alloy and temper.
The hole pattern drawing, with edge distances and thread sizes.
The end cut: square or mitre, and the angle.
The finish, and any bonding point to mask.
The quantity in pieces or metres.

Send those six items and the quotation comes back with the cutting, drilling, tapping and finish broken out separately. Browse the connecting elements range and the 40 series strut profiles that this angle is usually assembled with.

Have a frame assembly that needs a drilled angle?

Send the hole pattern and the member list. We quote the angle, the cutting, the drilling and the finish as separate lines.

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