Pawl clamp

T-Slot extruded aluminium profile joints – pawl clamp

Profile Joints – Part 5

Pawl clamp

In this post the focus is on the pawl clamping connector fastener, or ‘pawl clamp’ for short.  This is the fifth in our series of posts on aluminium profile joints.

pawl clamp

Pawl clamping connecting fastener

A joint constructed using a pawl clamp can have the relocatable advantage of a fixing plate, but via a single fixing screw rather than two. This means less stuffing about on those occasions when a joint needs to be moved.

Information about different styles of pawl clamp can be found on pages 2.53 to 2.56 of the Alusic catalogue.


The Alusic catalogue shows a pawl clamp for almost any joint type your application might require. The basic pawl clamp can be used in place of the standard connection to make a simple square joint, whether T or corner.

There are also pawl clamps that can be used to join profile pieces end-to-end, at an angle or straight, as shown in the diagram below.  This type of joint is stronger than the simpler linear joint or angular joint.  As a result, it can be used to construct a joint that can carry a bigger load, in tension, than a linear joint.

pawl clamp

Preparing the joint

Preparing the joint simply involves machining a hole of the correct diameter and depth in the first of the profiles to be joined. Exact dimensions for the holes to suit each pawl clamp are shown in the Alusic catalogue. The number of holes is determined by the number of pawl clamps the joint needs (2 in this example).

pawl clamp

Ready for assembly

pawl clamp

Joint partly assembled
















Assembling the joint

We can use two pawl clamps to join an 18.5×90 (084.101.006) to almost any profile with an 8mm t-slot. In this example we show it joined to an 18.5×32 (084.101.003), a 1 slot 40×40 (084.102.006), and a 6 slot 45×90 (084.101.019).

Start by putting the pawl(s) into the hole(s) machined in the first of the profiles to be joined.

The joint is completed simply by sliding the pawl clamp square nuts into the t-slot of the second of the profiles to be joined. When the required joint location is reached, simply use a hex key to tighten the fixing screws in place.

pawl clamp

18.5×90 joined to 18.5×32

pawl clamp

18.5×90 joined to 40×40

pawl clamp

18.5×90 joined to 45×90










So there you have it.  The pawl clamp; used to construct strong joints in extruded aluminium profiles, can be adapted to a variety of different joining requirements. The pawl clamp is so adaptable that it could readily be used in applications outside the realm of aluminium extrusions.  Use your imagination, almost any joint requirement can be fulfilled using pawl clamps.

If you want a copy of the Alusic catalogue to peruse on your PC, go to our site main page.  There is a place where you can enter your email address and click the Send button. We will then send you an email with a download link for the PDF file.