View Full Version : Joining aluminium extrusion lengthways

24-11-2014, 08:40 PM
The picture shows a proposed sliding table for a saw bench. Three aluminium profiles 40x80, 40x160, 45deg. side by side with 6mm aluminium top pieces. The width across the top surface is just over 300 mm, total length of the assembly will be 1250mm. As you can see it's fastened to two SBR rails with four bearings fastened to the machine.
The question is, how can I join the aluminium profiles together along their length ? I've looked on Motedis web site but can't see a suitable connector.


You can see the 'proper' sliding table here; http://www.hammerusa.com/us-us/products/table-saws/table-saw-k3-winner-48x48.html
and here if the video works for you;
http://www.hammerusa.com/videoplayer.php?id=http%3A%2F%2Fmirrorfelder.cnh.a t%2FDetailvideos%2FDetailvideos_Hammer%2FK3%2FK3_F ormatschiebetisch.flv

24-11-2014, 09:59 PM
Just a standard slide block and then drill the centre of the extrusion and bolt through from the side I believe

24-11-2014, 10:02 PM
I'd be interested in hearing of a good way to do this too. My only idea was to drill through the one profile, screw through and use a normal T Nut on the other. A bit more awkward with the angled profile though.

24-11-2014, 10:08 PM
Think Your going to have to drill some holes and use standard connector elements or T-nuts. Will be tricky on that angle piece thou.!

24-11-2014, 10:43 PM
Thanks for replies so far, it confirms what I thought even though it seems a basic and reasonable requirement.
I think I'll be drilling like you say and making a hardwood spline + Gorilla Glue for the angled piece.

25-11-2014, 07:07 AM
Possibly a stupid idea but how about a strip of Ali or strong plastic the shape of a double ended T nut then knock it in and cover with profile cap end

25-11-2014, 10:11 AM
Hi Eddy
You will have to drill the 40x160 right through and use stud iron same dia as the slot width, small lengths of flat bar drilled and tapped to fit the 45deg section and you want a hole in the 40x80 section for the stud iron and also a larger hole for the nut you are going to have to make to tighten it all up, you need some hex bar to make the nuts, just turn the hex down to to a slight clearance on the larger hole and drill and tap to suit your stud iron, or just machine a sleeve and fit some nice shiney dome nuts, ormake the hole big enough to get a socket in to tighten and fill the hole with a plastic plug.
The 40x160 could be drilled from either side as you have the accuracy of your CNC machine.

26-11-2014, 10:49 AM
I've ordered the parts now, will update with pictures once finished.

26-11-2014, 11:33 AM
Hi Edddy
If you decide to go with the method i mentioned it will make life easier if you tack weld the flat bar that goes in the 45deg section to the stud iron so you end up with a long bolt.

29-11-2014, 11:11 AM
You could give this (http://www.chronos.ltd.uk/engineering-tools/2013/durafix-aluminium-welding-brazing-soldering-rods-from-chronos/)type of stuff a go

29-11-2014, 09:01 PM
You could give this (http://www.chronos.ltd.uk/engineering-tools/2013/durafix-aluminium-welding-brazing-soldering-rods-from-chronos/)type of stuff a go

Funny you should mention that, I posted something similar myself a few weeks ago, http://www.mycncuk.com/threads/8045-Aluminium-Repair-and-joining-without-welding?p=63115#post63115 , but then forgot about it :stupid:

30-11-2014, 08:13 AM
Could you not drill a series of holes along the lengths of all the sections, counter bore all the holes on the outside two.
Insert threaded bars through the holes and tighten it all together with Nyloc locknuts.

13-12-2014, 09:25 PM
Done. Holes drilled right through, 8mm rod with dome nuts at the end and captive channel nuts in the 45deg extrusion.
Counterbores to allow a socket to be placed over the dome nuts was cut on the cnc router, it cut it like butter.
I was going to put 6mm aluminium top on it but to keep cost down I found some spare 10mm waterproof melamine faced plywood.
Also after using supported rail for the first time I can safely say that even though it works great for this application I would not use it myself for building a cnc machine.


13-12-2014, 09:30 PM
Nice job Eddy, is that a Felder ?

13-12-2014, 09:31 PM
Nice job Eddy, is that a Felder ?

Same company but slightly cheaper 'Hammer' brand.