Self Centering Drill Guide - for Aluminium Extrusions

The use is similar to some of my other models, like the Self Centering Gauge, Self Centering Drill Guide, or Compact Self Centering Gauge.

About the model

This is a drill guide specifically for extrusion profiles to get a centered hole through the profile. Since extrusion profiles have the notch in the middle, I found it quite difficult to properly align a dril over a distance marking and simultaneously in the middle of the profile in longitudinal direction.

That's where this tool comes in. You mark the distance like you normally would. Then just place the guide on the profile, align the middle marking with your distance mark, and secure the guide into place using the slot of the extrusion. After that, you can use any mask, depending on the size of the hole you want to drill. You can of course just use the bore of the guide itself, which alone maks it quite a bit easier to find the center of the slot. But using the right mask (or as close as possible to your drill size) makes drilling a centered hole into extrusion profiles a piece of cake.

The masks or templates for each hole size are designed to be able to print fast and with little material use. But as I mentioned, you can also use the guide itself without a mask, which will already improve the center-finding process.

Printing

Printing settings I used:

• 3 perimeters, 15% cubic infill
• 1mm top and bottom solid layers
• 0.2mm layer height
• print everything face down, so the text is on the printbed
• don't use crazy speeds, at least not for the first layer, as this might decrease the quality of the text

But the model is not particularly challenging to print. For the text on top of the model make sure to use at least 0.8mm bottom solid layers, since the text is 0.5mm deep.

The template models also include the corresponding main body. When importing into the slicer choose the option “Import as seperate bodies”. Don't print them on top of eachother, print them separately!

Using

To use the gauge you need the main body, which is different for each extrusion thickness. There is a model for 20x20, 30x30, and 40x40 profiles, which are the most common sizes.

After printing the main body you can choose from the variety of bore templates to fit the hole size you want to drill. You can of course also use a 5mm bore for a 4mm hole, as it will still provide good aid to align the drill correctly.

Then just mark your distance on the profile. You can also use the side of the centering gauge for alignment. The distance from the sides to the middle is provided as a text on top of the model. Then place the main body on the extrusion, twist to center and secure it into place with slot nuts. After that place the right bore template on top and drill away.

If you need a drill size thats not provided as a template there are also blanks in which you can cut the hole size you need (either in slicer or with a drill after printing).